The Intensity of the Geomagnetic Field During the Last 6 Millennia as Recorded by Slag Deposits From...

lable at ScienceDirect

Journal of Archaeological Science 35 (2008) 2863ndash2879

Contents lists avai

Journal of Archaeological Science

journal homepage ht tp wwwelsevier comlocate jas

A new approach for geomagnetic archaeointensity research insightson ancient metallurgy in the Southern Levant

E Ben-Yosef ab L Tauxe c H Ron b A Agnon b U Avner d M Najjar e TE Levy a

a University of California San Diego Department of Anthropology 9500 Gilman Drive La Jolla CA 92093 USAb Institute of Earth Sciences The Hebrew University of Jerusalem Jerusalem Israelc Scripps Institution of Oceanography UCSD La Jolla California USAd The Arava Institute for Environmental Studies Israele Department of Antiquity Amman Jordan

a r t i c l e i n f o

Article historyReceived 29 January 2008Received in revised form 15 May 2008Accepted 24 May 2008

KeywordsArchaeometallurgyCopper slagSlag depositsArchaeointensityPaleomagnetismSecular variationsTimnaFaynanChalcolithic

Corresponding author University of California Sathropology 9500 Gilman Drive La Jolla CA 92093 U

E-mail address ebenyosef06fulbrightweborg (E

0305-4403$ ndash see front matter 2008 Elsevier Ltddoi101016jjas200805016

a b s t r a c t

We present results from an archaeointensity investigation based on a relatively unexploited recordingmedium copper slag deposits Together with a recently improved experimental design for the archae-ointensity experiment we demonstrate the applicability of this medium as well as other archae-ometallurgical artifacts for the study of the ancient geomagnetic field intensity In addition toarchaeointensity data from well-dated archaeological contexts we obtained reliable archaeointensityresults from poorly dated or contentious archaeometallurgical sites in the Southern Levant These resultsshed new light on the dating of these sites among them the copper smelting installation of Timna 39b ndasha site that has important implications for the beginning of metallurgy during the fifth millennium BCEThe paper also aims to introduce archaeointensity research to the archaeologist scholar and to encouragefurther collaboration between the disciplines in future research

2008 Elsevier Ltd All rights reserved

1 Introduction

Archaeointensity research the study of the intensity of thegeomagnetic field as recorded by archaeological artifacts has pro-duced a vast amount of data since the 1950s (Donadini et al 2006Thellier and Thellier 1959) The data for the Middle East obtained todate are inconsistent and highly scattered (Fig 1) principally asa result of different materials used varying experimental methodsdifferent standards for evaluating the reliability of the laboratorialresults and poor time constraints This inconsistency together withlow data resolution in certain periods influences the accuracy andpredictability of derived geomagnetic field models (notablyCALSK72 see Korte and Constable 2005ab Korte et al 2005 anddashed line in Fig 1) In search of increasing reliability of archae-ointensity data we conducted a systematic investigation of a virtu-ally unexploited recording medium namely copper slag depositsTogether with a recently improved experimental design for the

n Diego Department of An-SA Tel thorn1 858 232 3882 Ben-Yosef)

All rights reserved

archaeointensity experiment we demonstrated the suitability ofthis medium as well as other materials from archaeometallurgicalcontext for archaeointensity studies (Ben-Yosef et al in press)

As part of applying and testing the new approach to archae-ointensity investigation we obtained highly reliable archae-omagnetic results from hundreds of specimens that originate fromarchaeometallurgical sites in the Southern Levant These resultsshed new light on the dating of some sites in the Timna valleyincluding the controversial site of Timna 39b situated in Israelrsquossouthern Negev desert In the following we present the methodo-logical concepts of archaeointensity research the advantages ofcopper slag deposits as an archaeointensity recorder and thearchaeointensity results obtained in the first stages of the currentstudy We also discuss the implication of our results on dating ofarchaeometallurgical sites and explore some applications ofarchaeointensity studies in the archaeological research in general

2 Archaeointensity research

Although the Earthrsquos magnetic field has been recognized fornearly 2000 years (Kono 2007) it is still one of the least

VA

DM

(Z

Am

2)

Age

0 100010002000300040005000 2000

CEBCE

160

140

120

100

80

60

40

Fig 1 Examples of archaeointensity data from the Near and Middle East for the lastseven millennia the period since the inception of copper smelting (after Ben-Yosefet al in press) The magnetic field strength is expressed as Virtual Axial Dipole Mo-ment (Zfrac14 1021) Large green triangles are data from Syria of Genevey et al (2003) bluesquares are from Gallet and Le Goff (2006) and brown dots are the Syrian data fromGallet et al (2006) Open red circles and squares are compilation of 11 other sourcesmostly based on fired clay (see Ben-Yosef et al in press for references) PredictedVADM values for Syria by CALS7K2 of Korte and Constable (2005a) are shown asdashed line The recent dipole value is shown as a solid black line (w80 ZAm2) (Forinterpretation of the references to colour in this figure legend the reader is referred tothe web version of this article)

E Ben-Yosef et al Journal of Archaeological Science 35 (2008) 2863ndash28792864

understood geophysical phenomena Its behavior provides insightson the inner workings of the Earth including geodynamics of theearly planet and changes in boundary conditions through time Itsstrength modulates the amount of cosmic radiation hitting theEarth thus contributing to factors such as the production ofcosmogenic isotopes in the atmosphere (including radiocarbon egFrank 2000 Kitagawa and Plicht 1998 Peristykh and Damon2003) and potentially even climatic changes (eg Courtillot et al2007 Gallet et al 2005)

The geomagnetic field is dynamic and undergoes randomchanges Small-scale variations (known as lsquolsquosecular variationsrsquorsquo)

a b

Fig 2 The Earthrsquos magnetic field and its elements (a) Magnetic field lines as predicted byinternational geomagnetic reference field from 1980 in the Earthrsquos mantle (green) (Courtessomewhat more complicated than that shown in (a) owing to non-axial dipole contributionthe specific location on the Earthrsquos surface (Ifrac14 inclination angle) (c) three elements of threpresented by the length of line B (For interpretation of the references to colour in this fi

occur constantly independent of the larger scale directional changesof reversals and excursions (eg Yamazaki and Oda 2004) Theyshow similar characteristics over an areal extent in the order of103 km and they consist of significant non-dipolar componentswhose magnitudes are debated (eg Constable et al 2000 Courtilotet al 1992) Reconstructing geomagnetic field behavior for the lastseveral millennia focuses on studying its secular variations and thusdepends strongly on position Improved prediction of geomagneticfield vectors awaits more sophisticated archaeosecular variationmodels based on reliable data from various regions of the world

Comprehensive investigation of the geomagnetic field requiresfull vector information for a known point in time (Fig 2) For thedirectional components there are instrumental records for the last400 years and for the intensity we have records since 1830s allincluded in the GUFM model of Jackson et al (2000) Reconstructingthe geomagnetic field prior to the instrumental recording dependson geological and archaeological recorders In most cases these re-corders are volcanic rocks and archaeological artifacts that acquireda thermal remanent magnetization (TRM) after cooling from Curietemperature (usually in the range of 300ndash600 C) Materials likebasaltic rocks pottery sherds and fired clay bricks are examples ofpaleomagnetic and archaeomagnetic recorders which preserve theproperties of the geomagnetic field from the last moment of cooling

While reconstructing the directional properties of the geo-magnetic field is a relatively easy procedure extracting the ancientintensity is a complex and laborious process (Valet 2003) Inprinciple it is possible to determine the intensity for ancientmagnetic fields because the primary mechanisms by which rocksand artifacts become magnetized can be approximately linearlyrelated to the ambient field for low fields such as the Earthrsquos Thuswe have by assumption

MNRMyaancHanc

and

MlabyalabHlab

where alab and aanc are dimensionless coefficients MNRM and Mlabare natural (ie original) and laboratory remanent magnetizationsrespectively and Hanc and Hlab are the magnitudes of the ancientand laboratory fields respectively If alab and aanc are equal we candivide the two equations and rearrange terms to get

North

Down

BI North

East

Down

D

I

B

BH

c

a simple model of geocentric axial dipole (b) magnetic field lines predicted from they of RL Parker) The core is the source of the field and is shown in yellow The field iss to the field The enlarged circle represents the vector of the geomagnetic field (B) fore geomagnetic fieldrsquos vector inclination angle (I) declination angle (D) and intensitygure legend the reader is referred to the web version of this article)

E Ben-Yosef et al Journal of Archaeological Science 35 (2008) 2863ndash2879 2865

Hanc frac14MNRM Hlab

Mlab

In other words if the laboratory remanence has the same pro-portionality constant with respect to the applied field as the ancientone the remanences are linearly related to the applied field andthe natural remanence (NRM) is composed solely of a single com-ponent all one needs to do to get the ancient field is measure MNRMgive the specimen a laboratory proxy remanence Mlab and multiplythe ratio between them by Hlab

In practice the estimation of paleointensity is not so simple Theremanence acquired in the laboratory may not have the same pro-portionality constant as the original remanence (eg the specimenhas altered its capacity to acquire remanence or was acquired bya mechanism not reproduced in the laboratory) The assumption oflinearity between the remanence and the applied field may not holdtrue Or the natural remanence may have multiple components ac-quired at different times with different constants of proportionality

A sophisticated experimental design is needed for validating thebasic assumptions of the method for tracking changes in themagnetic characteristic of a specimen throughout the experimentand for evaluating the reliability of the intensity results For ma-terials with thermal remanent magnetization the most commonexperimental design derives from the basic lsquolsquoThellierndashThellierrsquorsquoexperimental protocol (Thellier 1938 Thellier and Thellier 1959)

21 ThellierndashThellier experimental design and data interpretation

The theoretical basis for how ancient magnetic fields might bepreserved was clarified with the Nobel Prize-winning work of Neel(1949 1955) The theoretical basis for the experiments includingdetailed description and comparison with other methods was re-cently reviewed by Tauxe and Yamazaki (2007) Here we presentonly the basic principles of the laboratory work and data in-terpretation as a background for the archaeological discussion

The basic experiment involves heating specimens up in stagesprogressively replacing the NRM with partial thermal remanences

Temperature (degC)

Fractio

n N

RM

0 100 200 300 400 500

pTRM gained

Fraction NRM remaining

00

02

04

06

08

10

12a

Fig 3 A graphic representation of the lsquolsquoThellierndashThellierrsquorsquo type experiment The figures repthroughout the experiment Each point stands for a different temperature step (a) A plot shomagnetization) by laboratory partial TRM for each temperature step The fraction NRMremain

specimen is cooled in a laboratory field is the green line with the red squares (b) An lsquolsquoArai pabsolute value of the slope of the line connecting temperature steps (1871) is reflects the raarchaeointensity (56 mT) The linearity of this line and other parameters are used to determchecks (blue triangles expected to be in the same location of the corresponding temperatuzero) For further discussion see text and Ben-Yosef et al (in press) (For interpretation of the rarticle)

(pTRMs) in the hope of establishing the ratio MNRM=Mlab prior tothe onset of alteration This step-wise approach relies on the as-sumptions that pTRMs acquired by cooling between any twotemperature steps are independent of those acquired between anyother two temperature steps and that the total TRM is the sum ofall independent pTRMs

There are several options for ordering the sequential steps Forsimplicity the method of Coe (1967) is presented here In the firststep the specimen is heated to some temperature and cooled inzero field The measurement of the specimen will give us

Mfirst frac14 MNRM remaining

As an illustration we plot MNRM_remaining for a series of temperaturesteps as the blue line in Fig 3a In the second step the specimen isheated again to the same temperature and cooled in the laboratoryfield Hlab The measurement of the combined remanence (what isleft of the natural remanence plus the new laboratory pTRM) is

Msecond frac14 MNRM remaining thorn pTRM

Simple vector subtraction allows the determination of the pTRM forthis temperature step The pTRM of each temperature stage isplotted as the red line in Fig 3a Then we plot the pTRMs againstthe relevant NRMremaining and the result is a useful diagram (lsquoAraiplotrsquo Nagata 1961) for analyzing the behavior of the specimenthroughout the experiment (Fig 3b) The proportion between thepTRM and the NRMremaining should be constant and the slope of theline is the desired proportionality constant

slope frac14NRM NRMremaining

pTRM0Hanc frac14 Hlab slope

Additional steps in the same or lower temperatures provide testsfor various reliability checks in the experiment For example re-peating a lower temperature step and checking the pTRM acquired(lsquolsquopTRM checkrsquorsquo) indicates if the ability to acquire a pTRM haschanged during the experiment Demagnetizing the specimen after

00 01 02 03 04 05 06pTRM gained

00

02

04

06

08

10

12

Fractio

n N

RM

rem

ain

in

g

550

540

425deg

530520

b

resent one specimen (IS07a01) and the fractional pTRM it obtained in the laboratorywing the gradual destruction and replacement of NRM (the original [natural] remanent

ing after cooling in zero field is the blue line with circles and the pTRM gained when thelotrsquorsquo the NRMremaining at each temperature step is plotted against the pTRM gained Thetio of NRMTRM When multiplied by the lab field (30 mT) the slope gives the absoluteine the reliability of the archaeointensity result In addition the plot shows the pTRMre step eg at 530 C) and the pTRM-tail checks (blue square expected to be close toeferences to colour in this figure legend the reader is referred to the web version of this


it acquired a pTRM in the same temperature (lsquolsquopTRM-tail checkrsquorsquo)checks whether the blocking temperature is equal to the unblock-ing temperature an important prerequisite for reliable intensityresults These tests can be represented on the Arai plot (Fig 3b)

Interpretation of the results has to take into account numerousfactors and should be done for each specimen separately Firstthe segment of the experiment which represents the ancientmagnetic field should be identified usually using standard de-magnetization vector end-point diagrams for determining theoriginal magnetic component and Arai plot for spotting alterationThen the reliability of the relevant segment should be evaluatedusing aspects such as the linearity of the line in the Arai plot theresults of the relevant pTRM and pTRM-tail checks the number ofdata points in the relevant segment and others Many of theseaspects can be quantified and different combinations are used aslsquolsquoselection criteriarsquorsquo for determining a reliable intensity results (seereview in Tauxe 2006) The criteria used and their acceptancevalues vary among different studies and they depend on theexperimental protocols the materials used and the personalmethodology of the researcher

There are several other considerations regarding the reliabilityprecision and accuracy of the intensity results For example if thespecimen is anisotropic with respect to the acquisition of thermalremanence the anisotropy tensor must be determined and in-tensity corrected (eg Aitken et al 1981 Selkin et al 2000)Moreover because the approach to equilibrium is a function oftime slower cooling results in a larger TRM hence differences incooling rate between the original remanence acquisition and thatacquired in the laboratory will lead to erroneous results (eg Foxand Aitken 1980) Compensating for differences in cooling rate isrelatively straight forward if the original cooling rate is wellknown and the sample behaves according to single-domain the-ory This theory derives its name from the distribution of atomicmagnets within the macroscopic sample where no domains ofmutually contradicting magnetization might cancel each otherAlternatively one could take an empirical approach in which thespecimen is allowed to acquire a pTRM under varying coolingrates an approach useful for cooling periods of up to a day or 2For pottery fragments originally cooled inside kilns the over-estimation was shown experimentally to be by as much as 15ndash20 with an original cooling time of a day (from the Curie tem-perature) and an experimental cooling time of half an hour(Genevey and Gallet 2002)

Finally the intensity results should be evaluated in the sam-ple level according to the agreement between different speci-mens from the same original sample (ie the standard deviationcut-off) Usually a minimum number of lsquolsquowell-behavedrsquorsquo speci-mens per sample (N) is also determined as an additional cut-offvalue

22 Representation of geomagnetic intensity results ndash a commentabout units

The Systeme international (SI) basic unit for representingmagnetic induction (B) is tesla (T) Induction is often used in-terchangeably with the term magnetic field (H) with units of Ambecause in cgs units there is no difference between field andinduction While there is a significant difference in SI units (a factorof mo or 4p 107 henriesm) most researchers for simplicitycontinue to refer to the induction as the magnetic field but quotevalues in tesla For the Earthrsquos magnetic field which is relativelyweak it is convenient to use mT The field varies strongly asa function of latitude as expected from an essentially dipolar field(which is twice as strong at the poles than at the equator) There-fore when comparing data from different localities (ie differentlongitudeslatitudes) in the same region it is useful to lsquoreducersquo

them to a reference latitude by simple manipulation (eg Odahet al 1995)

Breduced frac14 Bsite

4 3cos2lreduced

4 3cos2lsite

12

wherel is the latitudeA more common way to compare geomagnetic intensity data

from different localities and regions is by presenting them as virtualaxial dipole moment (VADM)

VADM frac14 4pr3

m0Bancient

1thorn 3cos2q

12

where rfrac14 Earthrsquos radius [w6372000 m] m0frac14 permeability offree space constant and qfrac14 co-latitude Magnetic moments (asthe VADM) are measured in Am2 so magnetic fields (Am) canbe thought of as volume normalized magnetic moments Con-version to VADM eliminates the effect of the dipole on intensityand allows the possibility of regional differences derived fromsources of non-dipole moments to be assessed Represented asVADM the current geomagnetic intensity is 778 ZAm2

(Zetafrac14 1021)

23 The contribution of archaeology to geomagneticintensity research

Understanding the behavior of the geomagnetic fieldrsquos intensityover the last millennia is a key for studying various related phe-nomena such as solar activity (eg Usoskin et al 2006) the pro-duction of radiocarbon and other cosmogenic isotopes (egPeristykh and Damon 2003) the mechanisms of the geomagneticfield itself (eg Constable et al 2000) and perhaps even climatechanges (eg Courtillot et al 2007) Moreover the geomagneticfield has significantly reduced in strength over the last few decadesleading to speculation that it could collapse entirely as it undergoesa reversal of polarity (Constable and Korte 2006 Hulot et al 2002)The decay of the field has been observed since the beginning ofinstrumental recording over 160 years ago (Bloxham 2003) yeta better understanding of the geomagnetic intensity throughoutthe last millennia is needed for assessing the nature of the recentchange

For the last millennia as for the entire Holocene the bestsource for reconstructing the secular variations of the geo-magnetic field derives from the archaeological context (Folgher-aiter 1899 Thellier 1938) Since the innovation ofpyrotechnological industries in the Neolithic heated materials areabundant in the archaeological record The most commonly usedarchaeomagnetic recorders are artifacts of baked clay typicallypottery sherds fired mud bricks and kilnsrsquo walls (eg Fig 8) Theprimary advantage of these recorders is the ability to determinetheir age by the archaeological context For young (lt50 kyr)volcanic rocks another frequent paleomagnetic target age de-termination is a hard task and depends on the association of rareorganic materials trapped in or under the rock Sediments canalso be used for study of the ancient geomagnetic field (eg Tauxeand Yamazaki 2007 Valet 2003) but paleointensity informationis at best relative and the time scales are sometimes difficult toconstrain

The success rate of paleointensity experiments frequently doesnot exceed 10ndash20 (Valet 2003) It appears that archaeointensityexperiments get higher success rates especially when using a pre-experiment selection procedure (eg Genevey et al 2003) al-though many publications do not present the failed data or thevirtual success rates Thus novel materials are needed as part of theefforts to improve the success rates of these extremely time con-suming experiments

Fig 4 Embedded charcoal in a slag sample The charcoal enables a direct dating of thesample without relying on the archaeological context


3 Archaeointensity in archaeometallurgical context

31 Copper slag as an archaeointensity recorder

Copper slag samples have several distinct advantages asarchaeointensity recorders Frequently it is easy to collect charcoalsamples from the same context of the slag and retrieve radiocarbondates independently from the dating of the more general archae-ological locus assigned by the archaeologists The latter is oftenbased on complex stratigraphic and typological considerations thatare not always under consensus In some cases typically with as-sociation to advanced copper production technologies pieces ofcharcoal can be found embedded in the slag sample itself providingthe possibility for even more direct dating (Fig 4) As copper pro-duction and smelting was widespread in time and space particu-larly in the Old World beginning in the fifth millennium BCE theuse of slag for archaeointensity research is especially promising

Although slag samples vary in chemical composition appear-ance size mineralogy and texture depending on the raw ore andflux mixture and the specific technique of smelting used theyusually carry a strong magnetic remanence (Ben-Yosef et al inpress) This feature of slag enables the use of very small specimensin the archaeointensity experiments In addition abundant glassyparts in most of the slag samples increase the probability for single-domain magnetic particles and thus lsquolsquowell-behavedrsquorsquo specimensthroughout the experiment

Fig 5 Slag deposits in the Southern Levant (a) A w2 m profile of a partially excavated slagand Iron Age II (b) abundant slag mounds in Beer-Ora Valley (Timna 28) The slag deposit

In many copper production sites slag deposits are found inmultilayer mounds of debris (Fig 5) representing repeated phasesof smelting enabling a high resolution archaeointensity in-vestigation of specific periods However full vector analysis of theancient geomagnetic field is rarely possible as most of the samplesare not in their original cooling position In situ furnaces with slagattached (Fig 6) can be sampled for full vector reconstruction al-though they are scarce in the archaeological record In addition theinclination angle might be retrieved from tapping slag sampleswith clear horizontal surfaces (Fig 7a b)

Typically there is no need for cooling rate correction for copperslag samples Tapping slag common since the first millennium BCEpoured out of the furnace during the copper smelting processcooled rapidly in rates likely to be comparable to laboratory con-ditions (eg Merkel 1990) However furnace slag cools inside thefurnace and is likely to have cooled slower than the tapping slagNonetheless in antiquity furnaces were frequently broken apart sothat those carrying out the smelting could have rapid access to theslag and the copper prills embedded in it (eg Hauptmann 2007)Even if the furnaces were left intact and the slag allowed to cool insitu the furnaces were quite small (typically around 05 m indiameter or smaller) and the slag material would have been cool tothe touch within a few hours The most sizable over-estimationmight occur with furnace slag samples containing magnetic carrierswith low blocking temperatures (eg copperndashmagnesian ferrites)Yet that could result in overestimates of a few percent at most

As part of the current study we measured 210 furnace copperslag specimens and 149 tapping copper slag specimens from sites inIsrael and Jordan (see examples of samples in Fig 7) The resultsdemonstrate the suitability of copper slag material for archae-ointensity experiments and establish this medium as one of themost efficient geomagnetic intensity recorders For a thoroughdiscussion of the experiments and results including analysis ofslag anisotropy and magnetic characteristics see Ben-Yosef et al (inpress)

32 Other artifacts from archaeometallurgical context implicationsfor archaeointensity research

Ancient metal production industries are a source of varioustypes of samples suitable for the archaeointensity experiments(Fig 8) Slag from bronze (Ben-Yosef et al in press) and of ironproduction industries (Gram-Jensen et al 2000) have proven toyield reliable archaeointensity results These observations canprobably be extended to any type of slag including glass pro-duction industries however further research is needed In additionto the slag material there is a large variety of samples derived from

mound in the site of Timna 30 representing probably the Late Bronze Age II Iron Age Is represent intensive copper production in the Early Islamic period

Fig 6 Slag attached to the walls of in situ furnaces enables sampling for full geomagnetic vector analysis (a) The lower part of furnace lsquolsquoZrsquorsquo in site Timna 2 is a clay-lining lsquolsquopit in thegroundrsquorsquo (Rothenberg 1990b) (b) the stone built furnace lsquolsquoErsquorsquo in site Timna 2 with slag attached (Rothenberg 1990b)


clay found in archaeometallurgical contexts These include cruci-bles tuyeres bellow pipes moulds and furnacersquos linings as well asother associated clay artifacts These lsquolsquotechnologicalrsquorsquo or refractoryceramics were typically exposed to extremely high temperatures(gt1100 C) and in many cases have unique tempering and complexstructures making them resistant to the smelting and meltingprocesses Thus clay samples from archaeometallurgical contextare distinct from the commonly used baked clay artifacts such aspottery sherds (typically baked between 400 and 800 C) and firedmud bricks

Fig 7 Examples of slag samples (a) Broken tapping slag with flow textures looking at its topcooling enabling the reconstruction of the geomagnetic inclination angle (b) Broken tappinghorizontal position of the sample when cooling enabling the reconstruction of the geomaarchaeointensity experiments (c) Intact tapping slag sample Khirbat Hamra Ifdan Jordan (Ora Valley Israel) (g) Broken furnace slag from site Timna 39b

As part of the current study we also measured 28 specimensderived from five samples of refractory ceramics from archae-ometallurgical sites in the Southern Levant (Ben-Yosef et al inpress) The experiments yielded successful results for 25 specimens(w89 success rate) and for all of the samples (using rigorous se-lection criteria of more than two specimens [Ngt 2] and a standarddeviation [s] 10) Although the number of clay samples wassmall the results indicate that they are highly suitable for archae-ointensity studies We hope to test this observation with a muchlarger sample of refractory clay objects in the future

(Khirbat en-Nahas Jordan) Flat areas indicate the horizontal position of the slag whenslag with lsquolsquoslag dropletrsquorsquo embedded (Khirbat al-Jariya Jordan) The droplets indicate the

gnetic inclination angle The glassy texture makes the droplet itself a good source ford e) Glassy fragments of tapping slag (Khirbat en-Nahas Jordan) (f) lsquolsquoSlag cakersquorsquo (Beer-

Fig 8 Examples of baked clay artifacts from archaeometallurgical context (a) Clay rods (lsquolsquolady fingersrsquorsquo) and furnace fragments from site Fenan 15 Jordan (Early Bronze Age IIndashIII)(b) Clay crucible with slag coating Tell Gerisa Israel (Iron Age I) (c) Clay furnace fragment Khirbat en-Nahas Jordan (Iron Age II) (d) Tuyere fragment with slag coating Khirbat en-Nahas Jordan (Iron Age II) (e) Tuyere fragment back side Khirbat en-Nahas Jordan (Iron Age II) Note the composite structure of clay material (f) Bellow tube fragment Khirbat en-Nahas Jordan (Iron Age II) (g) Clay mould for casting copper ax Khirbat Hamra Ifdan Jordan (Early Bronze IV) (after Levy et al 2002)


4 Archaeometallurgy in the Southern Levant and theproblem of dating

The copper ore districts of southern Israel and Jordan are someof the richest ancient mining and metal production regions in theOld World comprising widespread evidence of archae-ometallurgical sites and slag deposits Together they provide keyareas for understanding the role of technology on social change andan exciting new sample set for archaeointensity research for thetime span of the last seven millennia

The first evidence of copper production in the Southern Levantgoes back as early as the fifth millennium BCE (eg Gorsdorf 2002Levy and Shalev 1989 Rothenberg and Merkel 1998) and corre-sponds with the period of metallurgical innovation throughout theancient Near East (eg Hauptmann 2000 2007) The archae-ometallurgical sites in the region span almost all of the archaeo-logical periods from the beginning of metal production in theChalcolithic period although at different resolutions (eg Avner2002 Rothenberg 1999b) through the Mamluk period in the 13thcentury CE (Hauptmann 2007)

The main centers of copper production in the Southern Levantare Faynan and Timna located along either side of the Wadi Arabah(the Arava Valley) (Fig 9) They are situated in the vicinity of naturalexposures of rich copper ore that are typically part of sandstone anddolomite host layers (Hauptmann 2007) Except for few othercopper smelting sites located near small exposures of copper orealong the Wadi Arabah and in the Sinai Peninsula other sites ofcopper industry required transportation of the ore for a relativelylong distance The Chalcolithic site of Shiqmim (Shalev andNorthover 1987) and the Early Bronze Ia site of Ashqelon-Afridar(Segal et al 2004) are examples of copper production industriesthat transported copper ore from Faynan more than 150 km away

The region of Timna has been intensively investigated by BenoRothenberg the director of the Arava archaeological expeditionbetween the years 1959 and 1990 (eg Rothenberg 1962 1999ab1990b) As part of this work more than 300 copper mining andproduction sites were documented (Wilson 1983) some of whichwere excavated Intermittent archaeological research in Timnacontinues to the present by the Israeli Antiquities Authority andUniversity College London

The archaeometallurgy of the Faynan district was systematicallyinvestigated by Andreas Hauptmann and a team from the

Deutsches Bergbau-Museum Bochum (DBM) between the years1983 and 1993 (eg Hauptmann 2007) Their work included sur-veys small-scale excavations and complementary laboratoryanalysis of the archaeometallurgical finds Since 1997 the area hasbeen the focus of intensive investigation as part of the EdomLowland Regional Archaeology Project of the University of Cal-ifornia San Diego (UCSD) and the Department of Antiquity Jordan(DOAJ) under the direction of Thomas Levy and Mohammad Najjar(eg Levy 2006) As one of the largest center of copper productionin the eastern Mediterranean the Faynan district is a prolific sourcefor archaeometallurgical studies Moreover the current UCSD-DOAJresearch in this area provides samples from well-defined contextusually with dating constrained by radiocarbon measurements

In Timna however the situation with regard to the dates ofmany sites is much more complex ndash in part because the excavationsmostly took place over 25 years ago In spite of the intensive re-search and the abundance of surveyed and excavated sites onlyscarce radiocarbon dates are available (Avner 2002 see in particularTable 2 which covers all the periods) The paucity of radiocarbondates generates a significant challenge for dating sites in the desertareas of the Wadi Arabah These ancient sites being remote fromthe populated centers of the Mediterranean and semi-arid regionswhere agriculture is relatively easy to practice show distinct re-gional characteristics in the material culture The ceramic typologyfor this region is much less refined especially in the early periodsform the Chalcolithic to the Iron Age (Avner 2002 Rothenberg andGlass 1992) thus hampering the possibility for high resolutioncontextual dating In some periods such as the Chalcolithic andEarly Bronze there are very little stylistic changes in the ceramicassemblage This results inter alia in difficulty for identifyingdesert sites to the Chalcolithic period in many of the early sites inthe Wadi Arabah both in the Faynan area (eg Adams 1998 Genz1997) and in the outskirts of Aqaba (eg Gorsdorf 2002 Khalil1987 1992 1995 Khalil and Eichmann 1999) In the Jordanian sitesthe ambiguity in dating was eventually resolved using high pre-cision radiocarbon measurements In Timna however the dating ofsome of the sites is still highly controversial such as the coppersmelting furnace of site Timna 39b (eg Rothenberg 1990a and seebelow Rothenberg and Merkel 1998)

The difficulty of establishing high resolution dates based on thematerial culture in the region of Timna led Rothenberg and glassto develop a different and more crude typologicalchronological

Fig 9 The major copper production centers in the Southern Levant


scheme for the desert sites divided into three assumed phases ofthe lsquolsquoSinai-Arabah Copper Agersquorsquo (Rothenberg and Glass 1992) Inaddition to distinctive ceramic and lithic types each phase wascharacterized also by an archaeometallurgical typology includingslag types (Rothenberg 1990b) For example slag features such asglassy textures viscosity amount of left-over copper mineralogyand chemistry were considered as chronological markers

The reliability of archaeometallurgical typology as a dating toolwas questioned by members of the Arava archaeological expeditionthemselves and other scholars (eg Avner 2002) and it becameclear that the technological development was not unilinearMoreover the chemical composition of slag varies according to theoriginal ore and flux mixture which depends primarily on thegeographical location rather than on the advances in technologiesNevertheless the archaeometallurgical typology was used fordating many sites such as N3 (Segal et al 1998) and 250b (Roth-enberg and Shaw 1990ab) These were dated to the Chalcolithicaccording to a similar lsquolsquotechnological horizonrsquorsquo as Site 39b a con-tentious site in itself

In many of the earliest archaeometallurgical sites it is difficult orimpossible to retrieve radiocarbon samples Slag samples asarchaeointensity recorders might hold the key for solving some of

the dating problems and clarify the archaeological picture of thedawn of metallurgy in the region Since the archaeointensity curvefor the Southern Levant is yet in low resolution a comparison withresults from well-dated archaeometallurgical sites is in cases nec-essary As part of the current study we investigated slag also fromsites of the more populated areas of the Beersheva Valley (Shiq-mim) the western Negev (Ashqelon-Afridar) and the centralcoastal plain of Israel (Tell Dor and Tell Gerisa) In the latter weinvestigated Iron Age I bronze melting sites (Ilan 1999) Howeverbefore focusing on the problem of the fifth millennium BCE it isimportant to examine the archaeointensity results for the entireseven millennia trajectory

5 Seven millennia of geomagnetic intensity changes in theSouthern Levant

51 Research methodology

As part of an investigation into slag material as an archae-ointensity recorder and in an effort to improve the resolution andreliability of the geomagnetic intensity curve for the last sevenmillennia we collected slag furnace and crucible fragments from

29degN

30degN

31degN

32degN

33degN

34degE 35degE 36degE

Shiqmim

Ashkelon -Afridar

Tell Gerisa

Hai-bar

Timna 28

Timna 2

Beer Ora Hill

Timna 3

Timna 30

Tel Hara Hadid

Yotvata

Yotvata Fortress

Givat Yocheved

Eilot quarry

Timna 149

Timna 39b

Mitzpe Evrona

Fidan 4

Khirbat Jariya

Khirbat Nahas

Fenan 15

El-Furn

Wadi Feidan 77Khirbat Hamra Ifdan

Khirbat Feinan

Fenan 1

Tell Dor

Fig 10 Archaeometallurgical sites that were sampled in the current study


27 archaeometallurgical sites in Israel and Jordan (Fig 10 Table 1)Most of the samples were collected during a field survey froma variety of archaeological contexts and others were taken fromcollections of previous archaeological excavations with the exactlocations well known (eg the sites of Shiqmim and Khirbat HamraIfdan) providing the best reference for further analysis

The main criteria used for choosing the sites were (1) datingquality with priority given to sites that have well-established ar-chaeological dating or reliable results from radiocarbon measure-ments (2) sites from periods that have distinct geomagneticarchaeointensity trends in previous studies such as the conspicu-ous peak in the Iron Age (ca 3000 years ago) and the low in theChalcolithic ndash Early Bronze Age (ca 5500 years ago) and (3) sites inwhich paleointensity data might help to solve questions concerningthe history of metallurgical technology such as Timna 39b

All of the dates assigned to our samples are based on prior ar-chaeological investigation of the sites We have not measured ra-diocarbon samples in this stage of the research although in manycases associated charcoal pieces are abundant and might be used inthe future The archaeological context constraining the age in-formation of the sample collection (see Table 1) is of variablequality depending on the collection method and the previous ar-chaeological work We have developed a scheme for characterizingthe age uncertainty of a sample based on the complex reality ofarchaeological investigation in our research area While the age

assigned might be precise (ie having a small deviation from themean) the archaeological context tying a given sample to a givenage may be weak or controversial In order to characterize thecontext itself we make use of various objective categories thatrelate to the methods of the original dating (eg radiocarbonmeasurements versus ceramic typology) the characteristic of thesite (eg presenting multi-periods or single period) and our samplecollection strategy (eg from confined excavated loci or surfacesurvey)

To summarize the relative reliability of our samples ages wehave assigned each age a number from 1 to 6 whereby 1 is con-sidered as excellent and 5 as poor Controversial sites are assigneda number 6 For the purposes of geomagnetic field modeling onlythe samples with age reliability of 1 and 2 should be consideredThe results from the rest of the samples are part of the discussionson the quality of slag as an archaeointensity recorder (Ben-Yosefet al in press) and on the dating of the sites from which they werecollected (below)

In this study every coherent fragment (piece of slag or clay) thatwe collected is called lsquolsquosamplersquorsquo and every chip of a sample is calledlsquolsquospecimenrsquorsquo From each sample we isolated four to 12 specimensranging from 2 to 7 mm in diameter The full name of a specimendesignates its location JS stands for Jordan IS stands for Israel andthe next two digits represent the site The sample piece is desig-nated with a letter and the specimen number with the last twodigits For example specimen JS01b03 is the third specimen fromthe b sample from the Wadi Fidan 4 site in Jordan (JS01) Wecatalogued and stored all of our samples in the paleomagneticlaboratory of the Institute of Earth Sciences in the Hebrew Uni-versity of Jerusalem and they constitute a large inventory for futureresearch

The specimens were inserted into non-magnetic glass tubes(1 cm in diameter) and went through a ThellierndashThellier type ex-periment using a sophisticated experimental protocol (the lsquolsquoIZZIrsquorsquoprotocol see Tauxe and Staudigel 2004 Yu and Tauxe in press Yuet al 2004) A detailed description of the experiments the selec-tion criteria used and our methodology in determining the cut-offvalues together with comprehensive results and statistical analysesare given in Ben-Yosef et al (in press)

52 Results

Our archaeointensity curve (Fig 11a and Table 2) is based onwell-dated samples (age quality 1 and 2) with at least three suc-cessful specimens (N 3) that are in good agreement with eachother (s cut-offfrac14 20 of the mean or within 5 mT) Fig 11b andTable 3 show the additional samples that passed the experimentaland statistical requirements but originated from a poorly dated orcontroversial context (age quality 3ndash5) For perspective we plotthe recently published data set from archaeointensity in-vestigation of Syrian sites (Gallet et al 2006 Gallet and Le Goff2006 Genevey et al 2003) together with the predicted VADM forthe region from the CALS7K2 model of Korte and Constable(2005a)

In total 30 samples out of 80 show reliable geomagnetic in-tensity results therefore representing a success rate (on a samplebasis) of 375 At the specimen level 236 out of 400 passed theexperimental requirements giving a general success rate of w60Comparing between specimens of furnace and tapping slag interms of success rate shows a slight preference towards furnaceslag The success rate of baked clay from archaeometallurgicalcontext was extremely high (89 in the specimens level and 100in the sample level) although the total number of specimens is only28 Bronze melting slag show similar success rate to furnace copperslag but in this case the number of specimens is limited makingthis inference tentative

Table 1Archaeometallurgical sites and samples in this study

Site name LatLong Agea Cb Coc Qd Se SNf Typeg Sh Refi

Southern Wadi Arabah (Timna area Israel)Timna 39b 2976334994 4200 250 ndash S 6 10 IS11 IS24 FS 611ndash13 33Hai-Bar 2983035020 3400 1100 ndash S 5 6 IS01 FS 1Yotvata fortress 2989035058 3860 500 S 2 1 IS17 FS ndash 1786Yotvata 2988535046 2650 350 ndash S 5 1 IS15 FS 1

0 100 ndash S 1 1 IS16 TS 1Eilot Quarry 2958934952 2650 350 ndash S 5 1 IS19 FS 201Beer-Ora Hill 2971734985 1785 20 S 2 4 IS07 FS 6Timna 149 2979235001 2150 150 ndash S 2 3 IS03 FS 2356

6 6 IS02 FS Timna 2 2978434948 1225 75 S 2 4 IS05 IS06 TS 10Timna 3 2977934952 1225 75 ndash S 2 3 IS08 TS 5Timna 30 2977134947 860 60 S 3 2 IS09 TS 10Timna 28 2971634984 850 150 S 2 2 IS04 TS 479Tell Hara-Hadid 2958934965 800 150 ndash S 3 5 IS10 TS ndash 1Givat-Yocheved 2964834939 800 150 S 6 1 IS18 TS 91810Mitzpe Evrona 2969534987 800 150 ndash S 3 1 IS25 TS ndash 9

Faynan area JordanFidan 4 3067335385 3250 250 S 1 3 JS01 FSC 2728Fenan 15 3062935497 2600 300 ndash S 1 2 JS04 FSC 28Khirbat Hamra Ifdan 3066335393 2450 150 E 1 1 JS09 FS ndash 31

2100 100 E 1 1 JS08 FS 311000 200 ndash S 4 1 JS06 TS ndash 32

Khirbat al-Jariya 3070735452 1030 110 S 1 2 JS02 TSC 28Khirbat en-Nahas 3068135437 850 50 S 1 3 JS03 TS ndash 2829Wadi Feidan 77 (lsquoKhirbat Glueckrsquo) 3067435391 1000 200 ndash E 3 1 JS07 FS ndash 32Fenan 7 3063035495 900 100 ndash S 5 1 JS10 TS ndash 28Fenan 1 3062635495 160 145 S 2 1 JS11 TS ndash 28El-Furn 3067535447 1250 50 ndash S 1 1 JS05 TS 28

Other sites in IsraelShiqmim 3119534639 4275 50 E 1 3 IS14 FSC 14ndash16Ashqelon-Afridar 3167934556 3475 125 E 4 3 IS20C FSC 21ndash24Tell Gerisa 3209134806 1100 100 ndash E 3 1 IS21 BS 25Tell Dor 3261734916 1100 100 ndash E 1 1 IS22 BS ndash 26

a Negative numbers are BCEb 14C dates available (calibrated with OxCal)c Collection method S surface collection during survey E collection from excavationd Age reliability scores 1 excellent 2 moderate to excellent 3 moderate 4 moderate to poor 5 poor 6 controversiale Number of samples measured from the sitef Sample namesg Type (crude categories) FS furnace slag TS tapping slag C clay BS bronze production slagh Successful experiment results for the site (according to our criteria see Ben-Yosef et al in press)i Most relevant references [1] Avner (personal communication 2006) [2] Rothenberg and Shaw (1990b) [3] Rothenberg and Shaw (1990a) [4] Rothenberg (1999b) [5]

Rothenberg and Glass (1992) [6] Avner (2002) [7] Sharon et al (1996) [8] Segal and Carmi (1996) [9] Avner and Magness (1998) [10] Rothenberg (1990b) [11] Rothenberg(1978) [12] Rothenberg (1990a) [13] Muhly (1984) [14] Gilead (1994) [15] Shalev and Northover (1987) [16] Burton and Levy (2001) [17] Meshel (1993) [18] Willies (1990)[20] Avner and Naor (1978) [21] Segal and Carmi (2004) [22] Gophna (2004) [23] Golani (2004) [24] Yekutieli (personal communication 2006) [25] Herzog (personalcommunication 2006) [26] Ilan (1999) [27] Adams (1999) [28] Hauptmann (2000) [29] Levy et al (2004) [31] Levy et al (2002) [32] Levy (personal communication 2007)[33] Burleigh and Hewson (1979)


Our archaeointensity curve shows acceptable agreement withthe data set from Syria (Gallet et al 2006 Gallet and Le Goff 2006Genevey et al 2003 see Fig 11a) As this region is close to theSouthern Levant and as these researchers used samples fromcareful archaeological contexts and modern strict experimentalprocedures we consider the comparison useful and the differentdata sets as complementary

The intensity of the geomagnetic field fluctuated rapidly overthe last 7000 years Major trends observed in previous studies wereconfirmed with our new results This includes the conspicuouspeak in intensity around 3000 years ago now shown to be evenhigher during the Iron Age I and the relatively long period of lowintensity prior to 5000 years ago (Chalcolithic ndash Early Bronze Age I)Two less prominent peaks are corroborated around 4500 years ago(Early Bronze Age IIndashIII) and 1200 years ago (Early Islamic) Our datasuggest a slightly lower trough 2000 years ago (Early Roman)

Not surprisingly the details of the archaeointensity curve do notagree precisely with the smoother depiction of the global model ofKorte and Constable (Korte and Constable 2005a) (see Fig 11a)Nevertheless most of the major trends of the geomagnetic

intensity are reflected in the model It seems to us that the reasonsfor the discrepancy are the current low resolution of the globalmodel and the use of some less rigorously obtained data asconstraints The published data include a variety of approachesmaterials and quality controls on paleointensity and dating hencemay contain a less than optimal recording of the geomagnetic field

6 Implications on dating of archaeometallurgical sites

Samples with reliable archaeointensity readings from poorlydated or controversial sites can contribute for constraining the ageof their context The results of the current research provide someinsights into the dating of certain archaeometallurgical sites in theSouthern Levant mainly in the region of Timna This includes thecontroversial site of Timna 39b

61 Timna 39b

The site of Timna 39b is considered by its excavator BenoRothenberg to be the most ancient copper smelting installation

Age

b

a

Age reliability scores gt 2σ cutoff = 20

20

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

20

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

σ cutoff = 20

Syrian data

CALSK72

All age reliability scores lt 3

IS04b

IS05a

IS06bIS07a

IS14c

JS01c

JS02b

JS04b

JS05a

IS06a

IS08c

IS16a

JS01b

JS04a

JS08a

IS01aIS01b IS02a

IS02f

IS09aIS10e

IS11b

IS11d

IS11e

IS11i

IS15a

IS17a

IS19a

IS18a

IS20c

IS21a

IS03b

0 1000 200030004000500060007000

BCE CE

0 1000 200030004000500060007000

BCE CE

IS02e

Fig 11 Summary of all acceptable sample intensities (with standard deviation cut-off values of 20 of the mean and N 3) (a) All samples have an age reliability index better than3 (Table 2) (b) Same as in (a) but including samples with uncertain ages (triangles) Small blue squares are data from Syria (Gallet et al 2006 Gallet and Le Goff 2006 Geneveyet al 2003) Predicted VADM values for Syria by CALSK7K2 of Korte and Constable (2005a) are shown as dashed line (For interpretation of the references to colour in this figurelegend the reader is referred to the web version of this article)


ever found anywhere (Rothenberg 1990a and many other publi-cations) Since its discovery (1960) and excavation (1965) there hasbeen a ceaseless debate regarding its age (eg Avner 2002 Crad-dock 2001) which has not reached a satisfactory resolution so far

The site is located in the southeastern part of Timna Valley ontop of a small hill facing the Wadi Arabah plain It was excavatedtogether with a domestic site situated ca 130 m to the southeast onthe lower slopes of the hill (Timna 39a) The final report (Rothen-berg 1978) connects the two sites and concludes that both are

dated to the early phase of the Chalcolithic Site 39a a householdunit with scarce evidence of ore and metal processing was firstdated primarily by the lithic assemblage (Bercovici 1978) TheChalcolithic age was confirmed later by radiocarbon measurementyielding the date of 5485 45 BP (435198 BCE 954 probabilityusing OxCal 40) (Rothenberg and Merkel 1998) Site 39b is a lsquolsquopit inthe groundrsquorsquo smelting furnace surrounded by many fragments ofsmall furnace slag with homogeneous visual characteristics(Fig 12) It is 30ndash40 cm in diameter and ca 40 cm in depth

Table 2Reliable archaeointensity results from well-dated archaeometallurgical sites in the Southern Levant (Fig 11)

Sample Site Age thorn Q N Bancient s VADM 1s

IS03b Timna 149 hillside 2150 150 2 3 44 101 855 859IS04b Timna 28 850 150 2 5 52 120 102 122IS05a Timna 2 1225 75 2 3 62 27 121 332IS06a Timna 2 1225 75 2 6 61 112 120 13IS06b Timna 2 1225 75 2 4 55 93 108 101IS07a Ora Hill 1785 20 2 3 56 22 110 245IS08c Timna 3 1225 75 2 4 50 186 97 180IS14c Shiqmim 4275 50 1 3 31 61 587 36IS16a Yotvata Nabataean 0 100 2 3 40 155 77 12JS01b Wadi Fidan 4 3250 250 1 4 23 64 436 28JS01c Wadi Fidan 4 3250 250 1 5 29 54 556 302JS02b Khirbat Jariya 1030 110 1 3 83 72 160 116JS04a Fenan 15 2600 300 1 4 52 15 100 151JS04b Fenan 15 2600 300 1 3 51 15 993 144JS05a El-Furn 1250 50 1 3 43 41 839 344JS08a Khirbat Hamra Ifdan 2100 100 1 5 36 148 686 102

For discussion on selection criteria applied see Ben-Yosef et al (in press) and text (Q age reliability scores N number of successful specimens age negative numbers are BCE)


although its partially stone lining suggests an upper structure ofadditional 40 cm (Rothenberg 1978) It was dated to the early phaseof the Chalcolithic primarily by relying on the typology of the lithicsuncovered in the small excavation around the furnace the slag andfurnace characteristics and the supposed connection to Site 39a(Rothenberg 1978 1990a Rothenberg and Merkel 1998)

Critical reservations regarding the early date of the furnace inSite 39b were raised even before the publication of the final reportby Muhly (1973 1976) He extended his criticism later on (Muhly1984) and was followed by various of other scholars (eg Adams1998 Avner 2002 Craddock 2001 Hanbury-Tenison 1986Weisgerber and Hauptmann 1988) In general these objections forthis early date are based on two aspects of the archaeometallurgicalresearch of the site The first is related to a comprehensive un-derstanding of the metal production in the Chalcolithic (eg Shalev1994) which claims that copper smelting was practiced withinvillages which could have been located far away from the ore Thisis the case in Beersheva valley (eg Gilead et al 1992 Levy andShalev 1989) and in recently discovered industries near Aqaba(Hauptmann et al 2004) The second aspect is related to the qualityof the archaeological evidence (see updated summary and discus-sion in Avner 2002)

The main arguments regarding the quality of the archaeologicalevidence include reassessment of the technology reservations ofthe models employed by the investigators and a previously un-published radiocarbon date from the furnace itself The furnace

Table 3Reliable archaeointensity results from poorly dated or controversial archaeometallurgica

Sample Site Age thorn Q

IS01a Hai-bar 3400 1100 5IS01b Hai-bar 3400 1100 5IS02a Timna 149 hilltop 2150 150 6IS02e Timna 149 hilltop 2150 150 6IS02f Timna 149 hilltop 2150 150 6IS09a Timna 30 860 60 3IS10e Tell Hara-Hadid 800 150IS11b Timna 39b 4200 250 6IS11d Timna 39b 4200 250 6IS11e Timna 39b 4200 250 6IS11i Timna 39b 4200 250 6IS15a Yotvata (EB) 2650 350 5IS18a Givat Yocheved 800 150 6IS19a Eilot quarry 2650 350 5IS20c Ashkelon-Afridar 3475 125 4IS21a Tell Gerisa 1100 100 3

For discussion on selection criteria applied see Ben-Yosef et al (in press ) and text (Qfrac14 aBCE)

structure and the characteristics of the slag were used by Rothen-berg as evidence for a suggested technology that is even earlierthan the Chalcolithic of Beersheva Valley (Rothenberg and Merkel1998) However revisiting of the evidence suggests an advancedpresumably late industry (eg Avner 2002) The supposed con-nection between Site 39a and the furnace is not decisive and theoriginal publication of the lithic assemblage did not distinguishbetween the two sites (Bercovici 1978) creating ambiguity in theinterpretation Most surprising is the radiocarbon date from thefurnace yielding the result of 1945 309 BP (Burleigh and Hewson1979) (761BCEndash645CE 954 probability using OxCal 40) Roth-enberg who characterizes this date as lsquolsquoLate Bronze Agersquorsquo (Roth-enberg 1990a) explains the date as being derived from refill of theexcavation pit that was brought from a different location Otherssuggest the possibility of reusing the smelting location andor in-stallation in the course of more than one period (Avner 2002)

Revisiting the site in 2004ndash2005 we collected 10 samples offurnace slag from the furnace itself and its close vicinity Foursamples (based on 16 specimens) passed all of our rigorous selec-tion criteria and yielded reliable archaeointensity results Theyclearly show three distinct groups of ancient geomagnetic intensity(Fig 13) implying at least three periods of copper production in thesite of Timna 39b The group showing the lowest intensity(66 7 ZAm2 VADM) might indeed represent copper smeltingduring the Chalcolithic It is within a one standard deviationagreement with the archaeointensity results obtained for the

l sites in the Southern Levant (Fig 11b)

N Bancient s VADM 1s

3 579 135 113 1534 597 92 117 1083 583 19 114 2195 55 129 108 1397 54 85 106 8973 64 181 125 2274 63 161 124 1993 546 80 107 8514 739 79 145 1144 34 100 665 6685 497 95 973 9253 677 26 132 3376 44 101 868 883 35 84 686 5739 558 161 107 1713 457 40 868 347

ge reliability scores N number of successful specimens age negative numbers are

Fig 12 The copper smelting installation in site Timna 39b and the excavated areasurrounding it


Chalcolithic site of Shiqmim (58 4 ZAm2 VADM) and is consistentwith the general low intensity throughout this period Neverthe-less this group is compatible with copper smelting in other periodsmainly the Early Bronze Age I The middle group as well mightrepresent several different periods of copper production includingEarly Bronze Age IIndashIII Middle and Late Bronze Age and Byzantinendash Early Islamic periods The latter corresponds to the radiocarbonmeasurement from the site The group with the highest intensity(14511 ZAm2 VADM) fits best to the Iron Age I period the latestphase of the intensive copper production in Timna region under theEgyptian influence (Rothenberg 1999b)

The archaeointensity results from Site 39b provide additionalsupport for Rothenbergrsquos early Chalcolithic dating although theydo not decisively prove it Moreover there might be a differencebetween the dating of copper production in the site and the datingof the installation found in situ today While our results support the

2000300040005000A

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

Tim

Fenan 15

Wadi Fidan 4

Khirbat

Ora

Khi

Shiqmim

Hai-bar

Timna 39b

Yotvata EB

Timna 39b

Timna 39b

Timna 149s

Ashkelon-Afridar Timna 149t

Eilot quarry

Fig 13 Curve combining Syrian (Gallet et al 2006 Gallet and Le Goff 2006 Genevey et alexcluding Timna 39b where three distinct groups of data were obtained Also shown are re149tfrac14 hilltop 149sfrac14 hillside) (see text for discussion) (For interpretation of the references t

idea that smelting activities occurred in more than one period theinstallation itself might represent only the latest one

We do not find the evidence of copper production near the or-igin of the ore during the Chalcolithic to be unique The evidenceof metallurgical activities in the Chalcolithic site of Timna 39a(Rothenberg 1978) together with other small sites in the Timnaregion such as N3 (Segal et al 1998) F2 (Rothenberg 1999aRothenberg and Merkel 1995) and 250b (Rothenberg and Shaw1990a) might suggest small-scale domestic copper production inperiods as early as the Chalcolithic although this evidence isproblematic (eg Avner 2002 Hauptmann and Wagner 2007) andmore research is needed Moreover in the light of other sites in theWadi Arabah the connection between sites 39a and 39b is a rea-sonable supposition In many cases the lsquolsquocold industryrsquorsquo of crushingthe ore and flux and processing slag was done at the foot of the hillwhile the pyrotechnological industry taking advantage of the windwas done on the top of the hill (eg Avner 2002 Site 189a Avnerand Naor 1978 Site 201a Rothenberg 1999ab) There is no doubtthat the vast majority of data for Chalcolithic smelting in thesouthern Levant comes from the Beersheva region and supports themodel of specialized industry far from the ore source However thenew archaeointensity data points to more than one mode of pro-duction during the fifth millennium BCE

62 Archaeometallurgical sites from later periods

The site of Timna 149 (Rothenberg 1999a Rothenberg andGlass 1992 Rothenberg and Shaw 1990ab) is located in thenortheastern part of the Timna Valley and considered by its exca-vator to be a key site for understanding the development of met-allurgy in the Early Bronze Age IV (ca 2200ndash2000 BCE) The siteconsists of two separate parts one on top of a hill facing the WadiArabah and the other on a plain to the west of the hill The latterwas excavated during 1984 and 1990 and dated by indicative ce-ramics from well-defined context to the Early Bronze Age IV Theexcavated area contains two shallow lines of walls ground stonesslag fragments and clay rods and was interpreted as a preparation

0 1000 20001000ge

na 2

Timna 3

El-Furn

Timna 28

Jariya

Hill

rbat Hamra Ifdan

Tell Gerisa

Timna 30

Givat Yocheved

Syrian dataage reliability lt 3age reliability gt 2

Tell Hara-Hadid

CEBCE

Yotvata Nabataean

2003) and Southern Levantine results (this study) We averaged results to the site levelliable archaeointensity results from poorly dated or controversial sites (green circleso colour in this figure legend the reader is referred to the web version of this article)


camp for the smelting process which took place on the top of thehill In addition the excavation suggests slag processing andprobably a secondary melting for the production of ingots (Roth-enberg and Shaw 1990b) The date of the finds from the hilltop ismuch less secure and based primarily on the supposed connectionto the excavated site of the hillside They include slag fragments andstones that were interpreted as part of sophisticated furnaces thatreplaced the earlier lsquolsquopit in the groundrsquorsquo type According to the ex-cavator they represent a progress in copper production attributedto this period (eg Rothenberg and Shaw 1990a)

Our archaeointensity results (Fig13) show clearly that there is noconnection between the metallurgical activities of the hillside andthe hilltop While results from the former are indeed in agreementwith data from previous studies and fit well in the Early Bronze AgeIV the results from the hilltop are distinct and represent a differentperiod This period is most probable the Late Bronze IIB (13th cen-tury BCE) when the copper production activity in the area reacheda climax under the Egyptian influence Several other periods are alsocompatible with our results including Early Islamic (638ndash1099 CE)and Early Bronze Age IIndashIII (ca 3000ndash2200 BCE) (Fig 13)

The alleged sophistication of the furnaces on the hilltop and theclaims for industrial scale of copper production with a break-through in technology (eg first appearance of tapping slag) arecontentious still regardless of their date (eg Avner 2002) Theconclusion about metallurgical activities during the Early BronzeAge IV should be reassessed under the light of the recently dis-covered large scale industry from this period in Faynan district(Levy et al 2002) as well as the interpretation of the finds from theexcavated industry in the hillside We suggest that the industry ofthe hillside included smelting in addition to preparation and pro-cessing activities The clay rods considered by the excavators to becomponents of crucible manufacturing (Rothenberg and Shaw1990b) might be part of the smelting installation as suggested forthe same type of finds from Faynan district (Hauptmann 19892000) In Faynan however the clay rods are part of wind-drivenfurnaces common in the Early Bronze II period

The samples from the site of Timna 30 were collected from layerI considered by the excavator to represent the most advanced an-cient copper smelting technology (Rothenberg 1999b) The site wasexcavated (Bachmann 1980 Rothenberg 1980 1999b 1990b) andlayer I was dated by Egyptian ceramic to the 22nd dynasty in par-ticular to the reign of Shishanq I A radiocarbon date yield even laterdate from the 8th century BCE (Rothenberg 1990b footnote 71)

The advanced technology represented in layer I and theuniqueness of the Iron Age II period raised some reservationsconcerning the date (eg Avner and Magness 1998 footnote 7) Ourarchaeointensity results fit well in the Iron Age II both to the periodof Shishanq I as well as to the 8th century BCE Because of the highpeak in the geomagnetic intensity in this period it is difficult toassign this layer to any other period

The site of Givat Yocheved (also known as Nahal Amram andTimna 33) is located 15 km south of Timna Valley near an intensivemining district It consists of several structures and mounds ofbroken tapping slag The Arava expedition dated the site to the NewKingdom (14thndash12th centuries BCE) (Rothenberg 1967 1990bfootnote 23) a date that was confirmed with a radiocarbon mea-surement from the bottom of the slag mound (Rothenberg 1990bfootnote 21) However based on the advanced metallurgical tech-nology evidenced at the site other scholars date the site to the EarlyIslamic period (Avner and Magness 1998) and point out anotherradiocarbon measurement from the same site yielded a date fromthe 8thndash9th centuries CE (Burleigh and Hewson 1979)

Our archaeointensity results (Fig 13) fit neither of the sugges-tions above and indicate most probably copper smelting in theEarly Roman period A date from the Middle Bronze Age or earlier(Fig 13) is inconsistent with the advanced tapping technology and

the Early Roman period is compatible with the intensive mining ofcopper ore from this period in the close vicinity (Avner and Mag-ness 1998 Willies 1990) However the site very likely representsmore than one period including the New Kingdom and Early Is-lamic as well

The site of Eilot Quarry was surveyed in the 1970s (Avner andNaor 1978) Its original Early Islamic date was changed to EarlyBronze Age according to new finds of lithic and ceramics (Avenerpersonal communication 2006) Our archaeointensity results(Fig 13) support the early date and constrain it to the Early BronzeAge Iearly phase of Early Bronze Age II

Our results from Tell Hara-Hadid (IS10e Fig 13) support its EarlyIslamic date This site is a large mound of tapping slag located a fewkilometers north of Elat It was previously dated by ceramics col-lected in a survey (not published yet)

The sites of Hai-Bar and Yotvata-EB in the Timna region areconsidered to be early according to the slag type and archae-ometallurgical typology According to our archaeointensity results(Fig 13) both are dated to later periods Hai-Bar can most probablybe dated to the Late Bronze Age ndash Iron Age I the climax of copperproduction in the area under the Egyptian influence Neverthelessother periods are also possible for this site such as the Early IslamicThe results from Yotvata-EB indicate Iron Age II smelting activitiesa date which makes it the second known site from this period in thesouthern part of the Wadi Arabah The revised dating of these sitesdemonstrates that slag and archaeometallurgical typology cannotbe used as a chronological marker and that the advancement incopper production technologies was accompanied by continuationof small-scale production using less sophisticated techniques

The site of Ashqelon-Afridar (Gophna 2004) is a large scaleEarly Bronze Age I settlement located in the southern part of thecoastal plain of Israel The excavation encountered ample archae-ometallurgical remains (Segal et al 2004) representing meltingand casting activities as well as smelting of copper ores Oursamples originated in area 10 excavated by Yekutieli in 1998 Al-though the finds from this area were dated to the Early Bronze AgeIa and show similar characteristic to the finds from nearby area E(Golani 2004) the specific samples (IS20ab) came from an in-secure context of refill in pits Our archaeointensity results suggesta later date for this phase of metallurgical activities associated withthe pits most probably Early Bronze Age IIndashIII (Fig 13)

Our archaeointensity results from Tell Gerisa (Fig 13) suggesta different date than Iron Age I The excavations are not yet pub-lished hampering any further discussion

7 Conclusions

71 Archaeointensity in the Levant ndash new horizons

The results from the current study demonstrate the suitability ofcopper slag material in archaeointensity research (see also Ben-Yosef et al in press) Together with the application of a sophisti-cated experimental protocol (the lsquolsquoIZZIrsquorsquo protocol of Tauxe andStaudigel 2004) we introduced a new and promising tool forstudying the behavior of the geomagnetic intensity during the lastseven millennia The abundant archaeometallurgical sites in theSouthern Levant provide an invaluable source of samples forarchaeointensity research Together with complementary sites inCyprus (eg Balthazar 1990) and Anatolia (eg Yener 2000) slagdeposits present a relatively high time resolution for the periodssince the dawn of metallurgy

We added 15 reliable archaeointensity results from well-datedcontexts to the archaeointensity curve of the Levant They are ingood agreement with previously published data from Syria (Galletet al 2006 Gallet and Le Goff 2006 Genevey et al 2003) andemphasize some of the heretofore observed trends in the


geomagnetic intensity behavior Further reliable archaeointensitydata from well-dated archaeological context are needed for im-proving the resolution of the highly fluctuating curve Such a highresolution curve in turn might be used in the archaeologicalresearch

72 Archaeointensity as a dating tool

The resolution of the current available archaeointensity curve ispoor and its application as a dating tool is limited In most casesother archaeological methods of dating such as radiocarbon ormaterial culture typologies are more probable to yield accurateresults However in certain sites where radiocarbon samples areunavailable and the material culture typology is problematic or inlow resolution the archaeointensity curve might be used as a ref-erence for dating This is the case in many of the archae-ometallurgical sites in the southern Wadi Arabah where thematerial culture cannot provide a decisive date Our reliablearchaeointensity results from such sites were compared to resultsfrom well-dated samples and to the available archaeointensitycurve providing several insights regarding the archaeometallurgyof this region

A significant conclusion is the nonlinear development of coppersmelting technologies Our results show clearly that ancient tech-nologies were still in use in later periods along with the advancedlarge scale production industry Slag and archaeometallurgy typol-ogy cannot therefore be used as a chronological marker Theymight however be related to social and political structures imply-ing differential accessibility to resources of knowledge and power

In addition metal production activities in site Timna 39b oc-curred in more than one period most probably including theChalcolithic The site of Timna 149 had hosted copper smelting inthe Early Bronze Age IV only in the excavated hillside part whilethe remains on the hilltop are from a distinct period probably re-lated to the proliferation of copper industry during the NewKingdom

Archaeointensity research focuses only on one component ofthe geomagnetic field Combining data from high resolution curvesof inclination and declination changes provide a strong dating toolfor the archaeologist based on a statistical matching of the threedifferent components (Lanos 2003) Applications of such a datingtechnique provide excellent results (eg Jordanova et al 2004Kovacheva et al 2004) and demonstrate the need for further reli-able archaeomagnetic data in the Southern Levant (see also Le Goffet al 2002)

Acknowledgements

We thank Jason Steindorf for many of the measurements andAnges Genevey for her contribution to the experimental part of thiswork Thanks are also due to Zeev Herzog Assaf Holtzer MichaelLevy Ron Shaar Sariel Shalev Naama Yahalom and Yuval Yekutielifor help in various aspects of this research We are grateful to DrFawwaz al-Khraysheh and the Department of Antiquity of Jordanfor assistance with the field work in Faynan Finally we would liketo thank three anonymous reviewers for their helpful comments

This study was supported by the FIRST program of the IsraelScience Foundation Grant No 133405 US-Israel Binational ScienceFoundation Grant No 200498 NSF grant EAR0636051 the US -Israel Educational Foundation Fulbright Grant for PhD students2006-2007 and the Academic Senate of UCSD

References

Adams RB 1998 On early copper metallurgy in the Levant a response to claims ofNeolithic metallurgy In Gebel HGK Kafafi Z Rollefson GO (Eds) The

Prehistory of Jordan II Perspectives from 1997 Studies in Early Near EasternProduction Subsistence and Environment 4 pp 651ndash656 Berlin

Adams RB 1999 The Development of Copper Metallurgy During the Early BronzeAge of the Southern Levant Evidence From the Faynan Region Southern JordanUniversity of Sheffield

Aitken MJ Alcock PA Bussell GD Shaw CJ 1981 Archaeomagnetic de-termination of the past geomagnetic intensity using ancient ceramics allow-ance for anisotropy Archaeometry 23 53ndash64

Avner U 2002 Studies in the Material and Spiritual Culture of the Negev and SinaiPopulations During the 6thndash3rd Millennia BC Hebrew University of JerusalemJerusalem

Avner U Magness J 1998 Early Islamic settlement in the southern Negev Bulletinof the American Schools of Oriental Research 310 39ndash57

Avner U Naor A 1978 A survey in the Eilat area Hadashot Arkheologiot 676866ndash68 (in Hebrew)

Bachmann HG 1980 Early copper smelting techniques in Sinai and in the Negevas deduced from slag investigations In Craddock PT (Ed) Scientific Studies inEarly Mining and Extractive Metallurgy pp 103ndash134 London

Balthazar JW 1990 Copper and Bronze Working in Early through Middle BronzeAge Cyprus Partille

Ben-Yosef E Ron H Tauxe L Agnon A Genevey A Levy TE Avner A Najjar M2008 Application of copper slag in geomagnetic archaeointensity researchJournal of Geophysical Research in press doi1010292007JB005235

Bercovici A 1978 Flint implements from Timna Site 39 In Rothenberg BTylecote RF Boydell PJ (Eds) Chalcolithic Copper Smelting Archaeo-met-allurgy 1 pp 16ndash20 London

Bloxham J 2003 Dipole decay secular variation and reversals Eos Trans AGU FallMeet (Suppl 84) F34

Burleigh R Hewson A 1979 British museum natural radiocarbon measurementsXI Radiocarbon 21 (3) 339ndash352

Burton M Levy T 2001 The Chalcolithic radiocarbon record and its use insouthern Levantine archaeology In Bruins H Carmi I Boaretto E (Eds) NearEast Chronology Archeology and Environment Radiocarbon vol 43 pp 1223ndash1246

Coe RS 1967 Paleointensities of the earthrsquos magnetic field determined from Ter-tiary and Quaternary rocks Journal of Geophysical Research 72 3247ndash5281

Constable C Korte M 2006 Is earthrsquos magnetic field reversing Earth and Plan-etary Science Letters 246 (1ndash2) 1ndash16

Constable CG Johnson CL Lund SP 2000 Global geomagnetic field models forthe past 3000 years transient or permanent flux lobes Philosophical Trans-actions of the Royal Society of London Series A 358 (1768) 991ndash1008

Courtillot V Gallet Y Le-Mouel J-L Fluteau F Genevey A 2007 Are thereconnections between the Earthrsquos magnetic field and climate Earth and Plan-etary Science Letters 253 328ndash339

Courtilot V Valet JP Hulot G Mouel JLL 1992 The Earthrsquos magnetic fieldwhich geometry Eos Trans AGU 73 (337) 340ndash342

Craddock PT 2001 From hearth to furnace evidence for the earliest metalsmelting technologies in the Eastern Mediterranean Paleorient 26 (2) 151ndash165

Donadini F Korthonen K Riisager P Pesonen LJ 2006 Database for Holocenegeomagnetic intensity information Eos Trans AGU 87 (14) 137

Folgheraiter M 1899 Sur les variations seculaires de lrsquoinclinaison magnetique danslrsquoantiquite Journal de Physique 5 660ndash667

Fox JMW Aitken MJ 1980 Cooling-rate dependence of thermoremanent mag-netization Nature 283 462ndash463

Frank M 2000 Comparison of cosmogenic radionuclide production and geo-magnetic field intensity over the last 200000 years Philosophical Transactionsof the Royal Society of London Series A 358 1089ndash1107

Gallet Y Genevey A Fluteau F 2005 Does Earthrsquos magnetic field secular variationcontrol centennial climate change Earth and Planetary Science Letters 236339ndash347

Gallet Y Genevey A Le Goff M Fluteau F Eshraghi SA 2006 Possible impact ofthe Earthrsquos magnetic field on the history of ancient civilizations Earth andPlanetary Science Letters 246 17ndash26

Gallet Y Le Goff M 2006 High-temperature archaeointensity measurementsfrom Mesopotamia Earth and Planetary Science Letters 241 159ndash173

Genevey A Gallet Y 2002 Intensity of the geomagnetic field in western Europeover the past 2000 years new data from ancient French pottery Journal ofGeophysical Research 107 (B11) 2285

Genevey A Gallet Y Margueron J 2003 Eight thousand years of geomagneticfield intensity variations in the eastern Mediterranean Journal of GeophysicalResearch 108 doi1010292001JB001612

Genz H 1997 Problems in defining a Chalcolithic for southern Jordan In Gebel HGK Kafafi Z Rollefson GO (Eds) The Prehistory of Jordan II Perspectivesfrom 1997 Studies in Early Near Eastern Production Subsistence and Envi-ronment 4 pp 441ndash448 Berlin

Gilead I 1994 The history of the Chalcolithic settlement in the Nahal Beer ShevaArea the radiocarbon aspect Bulletin of the American Schools of Oriental Re-search 296 1ndash13

Gilead I Rosen S Fabian P Rothenberg B 1992 New archaeological evidence forthe beginning of metallurgy in the Southern Levant Excavation at Tell AbuMatar Beersheba (Israel) 19901 Institute for Archaeo-metallurgical Studies 1811ndash14

Golani A 2004 Salvage excavations at the Early Bronze Age site of AshqelonAfridar ndash Area E rsquoAtiqot 45 9ndash62

Gophna R 2004 Excavations at Ashqelon Afridar ndash Introduction rsquoAtiqot 451ndash8


Gorsdorf J 2002 New 14C-datings of prehistoric settlements in the south of JordanOrient-Archaologie 5 333ndash339

Gram-Jensen M Abrahamsen N Chauvin A 2000 Archaeomagnetic intensity inDenmark Physics and Chemistry of the Earth A 25 525ndash531

Hanbury-Tenison JW 1986 The Late Chalcolithic to Early Bronze I Transition inPalestine and Transjordan Oxford

Hauptmann A 1989 The earliest periods of copper metallurgy in Feinan JordanIn Hauptmann A Pernicka E Wager GA (Eds) Old World Archae-ometallurgy Deutsche Bergbau-Museum Bochum pp 119ndash135

Hauptmann A 2000 Zur fruhen Metallurgie des Kupfers in FenanJordanien DerAnschnitt Bochum

Hauptmann A 2007 The Archaeometallurgy of Copper ndash Evidence from FaynanJordan Springer Berlin

Hauptmann A Khalil L Schmitt-Strecker S 2004 Evidence for Late ChalcolithicEarly Bronze Age I Copper Production from Timna ores at Tall Magass AqabaLevant

Hauptmann A Wagner I 2007 Prehistoric copper production at Timna TL-datingand evidence from the east In LaNiece DH Craddock P (Eds) Metals andMines Studies in Archaeometallurgy The British Museum amp Archetype Pub-lisher London pp 67ndash75

Hulot G Eymin C Langlais B Mandea M Olsen N 2002 Small-scale structureof the geodynamo inferred from Oersted and Magsat satellite data Nature 416620ndash623

Ilan D 1999 Northeastern Israel in the Iron Age I Cultural Socioeconomic andPolitical Perspectives Tel-Aviv University Tel-Aviv

Jackson A Jonkers ART Walker MR 2000 Four centuries of geomagnetic sec-ular variation from historical records Philosophical Transactions of the RoyalSociety of London Series A 358 (1768) 957ndash990

Jordanova N Kovacheva M Kostadinove M 2004 Archaeomagnetic in-vestigation and dating of Neolithic archaeological site (Kovachevo) fromBulgaria Physics of the Earth and Planetary Interiors 147 89ndash102

Khalil L 1987 Preliminary report on the 1985 season of excavation at el-Magass-Aqaba Annual of the Department of Antiquities of Jordan 31 481ndash483

Khalil L 1992 Some technological features from a Chalcolithic site at Magass-Aqaba Studies in History and Archaeology of Jordan IV 143ndash148

Khalil L 1995 The second season of excavation at al-Magass-Aqaba 1990 Annualof the Department of Antiquities of Jordan 39 65ndash79

Khalil L Eichmann R 1999 Archaeological survey and excavation at WadiAl-Yutum and Tall Al-Magass Area-lsquoAqaba (ASEYM) A preliminary report on thefirst season 1998 Annual of the Department of Antiquities of Jordan 43501ndash520

Kitagawa H Plicht J 1998 Atmospheric radiocarbon calibration to 45000 yr BPlate glacial fluctuations and cosmogenic isotope production Science 2791187ndash1190

Kono M 2007 Geomagnetism in perspective In Kono M (Ed) Geomagnetismvol 5 Elsevier Amsterdam pp 1ndash32

Korte M Constable C 2005a Continuous geomagnetic field models for the past 7millennia 2 CALS7K Geochemistry Geophysics Geosystems 6 Q02H16 doi1010292004GC000801

Korte M Constable C 2005b The geomagnetic dipole moment over the last 7000years ndash new results from a global model Earth and Planetary Science Letters236 348ndash358

Korte M Genevey A Constable C Frank U Schnepp E 2005 Continuousgeomagnetic field models for the past 7 millennia 1 A new global data com-pilation Geochemistry Geophysics Geosystems 6 Q02H15 doi1010292004GC000800

Kovacheva M Hedley I Jordanova N Kostadinove M Gigov v 2004 Archae-omagnetic dating of archaeological sites from Switzerland and Bulgaria Journalof Archaeological Science 31 1463ndash1479

Lanos P 2003 Bayesian inference of calibration curve application to Archae-omagnetism In Buck CE Millard AR (Eds) Tools for Chronology CrossingDisciplinary Boundaries Springer-Verlag London pp 43ndash82

Le Goff M Gallet Y Genevey A Warme N 2002 On archeomagnetic secularvariation curves and archeomagnetic dating Physics of the Earth and PlanetaryInteriors 134 203ndash211

Levy T 2006 Grand narratives technological revolutions and the past deep-timestudies of metallurgy and social evolution in the eastern Mediterranean InLaBianca O Scham SA (Eds) Connectivity in Antiquity ndash Globalization asa Long-term Historical Process Equinox London pp 10ndash25

Levy TE Adams RB Hauptmann A Prange M Schmitt-Strecker S Najjar M2002 Early Bronze Age metallurgy a newly discovered copper manufactory insouthern Jordan Antiquity 76 425ndash437

Levy TE Adams RB Najjar M Robinson M Higham T 2004 Reassessing thechronology of Biblical Edom new excavations and 14C dates from Khirbat enNahas (Jordan) Antiquity 78 863ndash876

Levy TE Shalev S 1989 Prehistoric metalworking in the southernLevant archaeometallurgical and social perspectives World Archaeology 20352ndash372

Merkel JF 1990 Experimental reconstruction of Bronze Age copper smeltingbased on archaeological evidence from Timna In Rothenberg B (Ed) Re-searches in the Arabah 1959ndash1984 Vol 2 The Ancient Metallurgy of CopperInstitute for Archaeo-metallurgical Studies London pp 78ndash122

Meshel Z 1993 Yotvata In Stern E (Ed) The New Encyclopedia of ArchaeologicalExcavations in the Holy Land vol IV pp 1517ndash1520 Jerusalem

Muhly JD 1973 Copper and Tin New-HavenMuhly JD 1976 Supplement to Copper and Tin Hamden

Muhly JD 1984 Timna and King Solomon Bibliotheca Orientalis XLI (3ndash4)276ndash292

Nagata T 1961 Rock MagnetismNeel L 1949 Theorie du trainage magnetique des ferromagneetiques en

grains fines avec applications aux terres cuites Annales de Geophysique 599ndash136

Neel L 1955 Some theoretical aspects of rock-magnetism Advances in Physics 4191ndash243

Odah H Heider F Hussain AG Hoffmann V Soffel H ElGamili M 1995Paleointensity of the geomagnetic field in Egypt from 4000 BC to 150 AD usingthe Thellier method Journal of Geomagnetism and Geoelectricity 47 41ndash58

Peristykh AN Damon PE 2003 Persistense of the glessberg 88-year solar cycleover the last 12000 years evidence from cosmogenic isotopes Journal ofGeophysical Research 108 doi1010292002JA009390

Rothenberg B 1962 Ancient copper industries in the western Arabah PalestineExploration Quarterly 5ndash71

Rothenberg B 1967 Negev Archaeology in the Negev and the Arabah MasadaTel-Aviv

Rothenberg B 1978 Excavation at Timna Site 39 In Rothenberg B (Ed)Chalcotithic Copper Smelting Institute for Archaeo-metallurgical StudiesLondon pp 1ndash26

Rothenberg B 1980 Die archaeologie des verhuttungslagers Site 30 In Conrad HG Rothenberg B (Eds) Antikes Kupfer im Timna-Tal pp 187ndash214 Bochum

Rothenberg B 1990a The Chalcolithic copper smelting furnace in the Timna valleyndash its discovery and the strange argument surrounding its dating Institute forArchaeo-metallurgical Studies News letter 15ndash16 9ndash12

Rothenberg B 1999a Archaeo-metallurgical researches in the southern Arabah1959ndash1990 Part 1 Late Pottery Neolithic to Early Bronze IV Palestine Explo-ration Quarterly 131 68ndash89

Rothenberg B 1999b Archaeo-metallurgical researches in the southern Arabah1959ndash1990 Part 2 Egyptian New Kingdom (Ramesside) to Early Islam Pales-tine Exploration Quarterly 131 149ndash175

Rothenberg B (Ed) 1990b Researches in the Araba 1959ndash1984 Vol 2 The AncientMetallurgy of Copper Institute for Archaeo-metallurgical Studies London

Rothenberg B Glass J 1992 Beginnings and development of early metallurgy andthe settlement and chronology of the western Arabah from the Chalcolithicperiod to Early Bronze Age IV Levant 24 141ndash157

Rothenberg B Merkel JF 1995 Late Neolithic copper smelting in the ArabahInstitute for Archaeo-metallurgical Studies News letter 19 1ndash7

Rothenberg B Merkel JF 1998 Chalcolithic 5th millennium BC copper smeltingat Timna Institute for Archaeo-metallurgical Studies News letter 20 1ndash3

Rothenberg B Shaw CT 1990a Chalcolithic and Early Bronze Age IV coppermining and smelting in Timna Valley (Israel) ndash excavations 1984ndash1990 InPertovic P Durdekanovic S (Eds) Ancient Mining and Metallurgy in SouthernEurope pp 281ndash294 Belgrade

Rothenberg B Shaw CT 1990b The discovery of a copper mine and smelter fromthe end of the Early Bronze Age (EBIV) in the Timna Valley Institute forArchaeo-metallurgical Studies News letter 15ndash16 1ndash8

Segal D Carmi I 1996 Rehovot Radiocarbon Date List V rsquoAtiqot XXIX 79ndash106Segal D Carmi I 2004 Determination of age using the 14C method on

archaeobotanical samples from Ashqelon Afridar ndash area E rsquoAtiqot 45 119ndash120Segal I Halicz L Kamenski A 2004 The metallurgical remains from Ashqelon

Afridar ndash areas E G and H rsquoAtiqot 45 311ndash330Segal I Rothenberg B Bar-Matthews M 1998 Smelting slag from prehistoric

sites F2 and N3 in Timna SW Arabah Israel In Rehren T Hauptmann AMuhly JD (Eds) Metallurgica Antiqua vol 8 pp 223ndash234 Bochum

Selkin PA Gee JS Tauxe L Meurer WP Newell A 2000 The effect of rema-nence anisotropy on paleointensity estimates a case study from the ArcheanStillwater complex Earth and Planetary Science Letters 182 403ndash416

Shalev S 1994 Change in metal production from the Chalcolithic Period to theEarly Bronze Age in Israel and Jordan Antiquity 68 630ndash637

Shalev S Northover P 1987 The Chalcolithic metal and metalworking fromShiqmim In Levy TE (Ed) Shipmim I ndash Studies Concerning Chalcolithic So-cieties in the Northern Negev Desert Israel (1982ndash1984) British ArchaeologicalReports International Series 356 Oxford pp 357ndash371

Sharon M Avner U Nahlieli D 1996 An Early Islamic mosque near Bersquoer Ora inthe southern Negev possible evidence for an early eastern Qiblah rsquoAtiqot XXX107ndash119

Tauxe L 2006 Long-term trends in paleointensity the contribution of DSDPODPsubmarine basaltic glass collections Physics of the Earth and Planetary Interiors156 (3ndash4) 223ndash241

Tauxe L Staudigel H 2004 Strength of the geomagnetic field in the CretaceousNormal Superchron new data from submarine basaltic glass of the TroodosOphiolite Geochemistry Geophysics Geosystems 5 (2) Q02H06 doi1010292003GC000635

Tauxe L Yamazaki T 2007 Paleointensities In Kono M (Ed) Geomagnetismvol 5 Elsevier Amsterdam pp 509ndash564

Thellier E 1938 Sur lrsquoaimantation des terres cuites et ses applications geophysiqueIn Annales de lrsquoInstitut de Physique du Globe Universite de Paris 16 157ndash302

Thellier E Thellier O 1959 Sur lrsquointensite du champ magnetique terrestre dans lepasse historique et geologique Annales Geophysicae 15 285ndash378

Usoskin IG Solanki SK Korte M 2006 Solar activity reconstructed over the last7000 years the influence of geomagnetic field changes Geophysical ResearchLetters 33 doi1010292006GL25921

Valet JP 2003 Time variations in geomagnetic intensity ndash art no 1004 Reviews ofGeophysics 41 (1) 1004


Weisgerber G Hauptmann A 1988 Early copper mining and smelting in PalestineIn Maddin R (Ed) The Beginning of the Use of Metals and Alloys Papers fromthe Second International Conference on the Beginning of the Use of Metals andAlloys Zhengzhou China 21ndash26 October 1986 pp 52ndash62 Cambridge

Willies L 1990 Exploring the ancient copper mines of the Wadi Amram (southArabah) Institute for Archaeo-metallurgical Studies Newsletter 15ndash16 12ndash15

Wilson AJe 1983 Institute for Archaeo-metallurgical Studies Newsletter 5Yamazaki T Oda H 2004 Intensityndashinclination correlation for long-term secular

variation of the geomagnetic field and its relevance to persistent non-dipole

components In Channell JET (Ed) Timescales of the Paleomagnetic Fieldvol 145 American Geophysical Union Washington DC pp 287ndash298

Yener SA 2000 The Domestication of Metals The Rise of Complex MetalIndustries in Anatolia Brill

Yu Y Tauxe L Testing the IZZI protocol of geomagnetic field intensitydetermination Geochemistry Geophysics Geosystems in press

Yu Y Tauxe L Genevey A 2004 Toward an optimal geomagnetic field intensitydetermination technique Geochemistry Geophysics Geosystems 5 (2)Q02H07 doi1010292003GC000630

VA

DM

(Z

Am

2)

Age

0 100010002000300040005000 2000

CEBCE

160

140

120

100

80

60

40

Fig 1 Examples of archaeointensity data from the Near and Middle East for the lastseven millennia the period since the inception of copper smelting (after Ben-Yosefet al in press) The magnetic field strength is expressed as Virtual Axial Dipole Mo-ment (Zfrac14 1021) Large green triangles are data from Syria of Genevey et al (2003) bluesquares are from Gallet and Le Goff (2006) and brown dots are the Syrian data fromGallet et al (2006) Open red circles and squares are compilation of 11 other sourcesmostly based on fired clay (see Ben-Yosef et al in press for references) PredictedVADM values for Syria by CALS7K2 of Korte and Constable (2005a) are shown asdashed line The recent dipole value is shown as a solid black line (w80 ZAm2) (Forinterpretation of the references to colour in this figure legend the reader is referred tothe web version of this article)


understood geophysical phenomena Its behavior provides insightson the inner workings of the Earth including geodynamics of theearly planet and changes in boundary conditions through time Itsstrength modulates the amount of cosmic radiation hitting theEarth thus contributing to factors such as the production ofcosmogenic isotopes in the atmosphere (including radiocarbon egFrank 2000 Kitagawa and Plicht 1998 Peristykh and Damon2003) and potentially even climatic changes (eg Courtillot et al2007 Gallet et al 2005)

The geomagnetic field is dynamic and undergoes randomchanges Small-scale variations (known as lsquolsquosecular variationsrsquorsquo)

a b

Fig 2 The Earthrsquos magnetic field and its elements (a) Magnetic field lines as predicted byinternational geomagnetic reference field from 1980 in the Earthrsquos mantle (green) (Courtessomewhat more complicated than that shown in (a) owing to non-axial dipole contributionthe specific location on the Earthrsquos surface (Ifrac14 inclination angle) (c) three elements of threpresented by the length of line B (For interpretation of the references to colour in this fi

occur constantly independent of the larger scale directional changesof reversals and excursions (eg Yamazaki and Oda 2004) Theyshow similar characteristics over an areal extent in the order of103 km and they consist of significant non-dipolar componentswhose magnitudes are debated (eg Constable et al 2000 Courtilotet al 1992) Reconstructing geomagnetic field behavior for the lastseveral millennia focuses on studying its secular variations and thusdepends strongly on position Improved prediction of geomagneticfield vectors awaits more sophisticated archaeosecular variationmodels based on reliable data from various regions of the world

Comprehensive investigation of the geomagnetic field requiresfull vector information for a known point in time (Fig 2) For thedirectional components there are instrumental records for the last400 years and for the intensity we have records since 1830s allincluded in the GUFM model of Jackson et al (2000) Reconstructingthe geomagnetic field prior to the instrumental recording dependson geological and archaeological recorders In most cases these re-corders are volcanic rocks and archaeological artifacts that acquireda thermal remanent magnetization (TRM) after cooling from Curietemperature (usually in the range of 300ndash600 C) Materials likebasaltic rocks pottery sherds and fired clay bricks are examples ofpaleomagnetic and archaeomagnetic recorders which preserve theproperties of the geomagnetic field from the last moment of cooling

While reconstructing the directional properties of the geo-magnetic field is a relatively easy procedure extracting the ancientintensity is a complex and laborious process (Valet 2003) Inprinciple it is possible to determine the intensity for ancientmagnetic fields because the primary mechanisms by which rocksand artifacts become magnetized can be approximately linearlyrelated to the ambient field for low fields such as the Earthrsquos Thuswe have by assumption

MNRMyaancHanc

and

MlabyalabHlab

where alab and aanc are dimensionless coefficients MNRM and Mlabare natural (ie original) and laboratory remanent magnetizationsrespectively and Hanc and Hlab are the magnitudes of the ancientand laboratory fields respectively If alab and aanc are equal we candivide the two equations and rearrange terms to get

North

Down

BI North

East

Down

D

I

B

BH

c

a simple model of geocentric axial dipole (b) magnetic field lines predicted from they of RL Parker) The core is the source of the field and is shown in yellow The field iss to the field The enlarged circle represents the vector of the geomagnetic field (B) fore geomagnetic fieldrsquos vector inclination angle (I) declination angle (D) and intensitygure legend the reader is referred to the web version of this article)



Mlab







Temperature (degC)

Fractio

n N

RM

0 100 200 300 400 500

pTRM gained


00

02

04

06

08

10

12a












00 01 02 03 04 05 06pTRM gained

00

02

04

06

08

10

12

Fractio

n N

RM

rem

ain

in

g

550

540

425deg

530520

b












4 3cos2lreduced

4 3cos2lsite

12



VADM frac14 4pr3

m0Bancient

1thorn 3cos2q

12


(Zetafrac14 1021)













































29degN

30degN

31degN

32degN

33degN


Shiqmim

Ashkelon -Afridar

Tell Gerisa

Hai-bar

Timna 28

Timna 2

Beer Ora Hill

Timna 3

Timna 30

Tel Hara Hadid

Yotvata

Yotvata Fortress

Givat Yocheved

Eilot quarry

Timna 149

Timna 39b

Mitzpe Evrona

Fidan 4

Khirbat Jariya

Khirbat Nahas

Fenan 15

El-Furn


Khirbat Feinan

Fenan 1

Tell Dor










52 Results





















61 Timna 39b


Age

b

a


20

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

20

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

σ cutoff = 20

Syrian data

CALSK72


IS04b

IS05a

IS06bIS07a

IS14c

JS01c

JS02b

JS04b

JS05a

IS06a

IS08c

IS16a

JS01b

JS04a

JS08a

IS01aIS01b IS02a

IS02f

IS09aIS10e

IS11b

IS11d

IS11e

IS11i

IS15a

IS17a

IS19a

IS18a

IS20c

IS21a

IS03b

0 1000 200030004000500060007000

BCE CE

0 1000 200030004000500060007000

BCE CE

IS02e






















3 579 135 113 1534 597 92 117 1083 583 19 114 2195 55 129 108 1397 54 85 106 8973 64 181 125 2274 63 161 124 1993 546 80 107 8514 739 79 145 1144 34 100 665 6685 497 95 973 9253 677 26 132 3376 44 101 868 883 35 84 686 5739 558 161 107 1713 457 40 868 347






2000300040005000A

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

Tim

Fenan 15

Wadi Fidan 4

Khirbat

Ora

Khi

Shiqmim

Hai-bar

Timna 39b

Yotvata EB

Timna 39b

Timna 39b

Timna 149s


Eilot quarry






0 1000 20001000ge

na 2

Timna 3

El-Furn

Timna 28

Jariya

Hill

rbat Hamra Ifdan

Tell Gerisa

Timna 30

Givat Yocheved


Tell Hara-Hadid

CEBCE

Yotvata Nabataean
















7 Conclusions











Acknowledgements



References
















































































































Mlab







Temperature (degC)

Fractio

n N

RM

0 100 200 300 400 500

pTRM gained


00

02

04

06

08

10

12a












00 01 02 03 04 05 06pTRM gained

00

02

04

06

08

10

12

Fractio

n N

RM

rem

ain

in

g

550

540

425deg

530520

b












4 3cos2lreduced

4 3cos2lsite

12



VADM frac14 4pr3

m0Bancient

1thorn 3cos2q

12


(Zetafrac14 1021)













































29degN

30degN

31degN

32degN

33degN


Shiqmim

Ashkelon -Afridar

Tell Gerisa

Hai-bar

Timna 28

Timna 2

Beer Ora Hill

Timna 3

Timna 30

Tel Hara Hadid

Yotvata

Yotvata Fortress

Givat Yocheved

Eilot quarry

Timna 149

Timna 39b

Mitzpe Evrona

Fidan 4

Khirbat Jariya

Khirbat Nahas

Fenan 15

El-Furn


Khirbat Feinan

Fenan 1

Tell Dor










52 Results





















61 Timna 39b


Age

b

a


20

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

20

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

σ cutoff = 20

Syrian data

CALSK72


IS04b

IS05a

IS06bIS07a

IS14c

JS01c

JS02b

JS04b

JS05a

IS06a

IS08c

IS16a

JS01b

JS04a

JS08a

IS01aIS01b IS02a

IS02f

IS09aIS10e

IS11b

IS11d

IS11e

IS11i

IS15a

IS17a

IS19a

IS18a

IS20c

IS21a

IS03b

0 1000 200030004000500060007000

BCE CE

0 1000 200030004000500060007000

BCE CE

IS02e






















3 579 135 113 1534 597 92 117 1083 583 19 114 2195 55 129 108 1397 54 85 106 8973 64 181 125 2274 63 161 124 1993 546 80 107 8514 739 79 145 1144 34 100 665 6685 497 95 973 9253 677 26 132 3376 44 101 868 883 35 84 686 5739 558 161 107 1713 457 40 868 347






2000300040005000A

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

Tim

Fenan 15

Wadi Fidan 4

Khirbat

Ora

Khi

Shiqmim

Hai-bar

Timna 39b

Yotvata EB

Timna 39b

Timna 39b

Timna 149s


Eilot quarry






0 1000 20001000ge

na 2

Timna 3

El-Furn

Timna 28

Jariya

Hill

rbat Hamra Ifdan

Tell Gerisa

Timna 30

Givat Yocheved


Tell Hara-Hadid

CEBCE

Yotvata Nabataean
















7 Conclusions











Acknowledgements



References























































































































4 3cos2lreduced

4 3cos2lsite

12



VADM frac14 4pr3

m0Bancient

1thorn 3cos2q

12


(Zetafrac14 1021)













































29degN

30degN

31degN

32degN

33degN


Shiqmim

Ashkelon -Afridar

Tell Gerisa

Hai-bar

Timna 28

Timna 2

Beer Ora Hill

Timna 3

Timna 30

Tel Hara Hadid

Yotvata

Yotvata Fortress

Givat Yocheved

Eilot quarry

Timna 149

Timna 39b

Mitzpe Evrona

Fidan 4

Khirbat Jariya

Khirbat Nahas

Fenan 15

El-Furn


Khirbat Feinan

Fenan 1

Tell Dor










52 Results





















61 Timna 39b


Age

b

a


20

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

20

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

σ cutoff = 20

Syrian data

CALSK72


IS04b

IS05a

IS06bIS07a

IS14c

JS01c

JS02b

JS04b

JS05a

IS06a

IS08c

IS16a

JS01b

JS04a

JS08a

IS01aIS01b IS02a

IS02f

IS09aIS10e

IS11b

IS11d

IS11e

IS11i

IS15a

IS17a

IS19a

IS18a

IS20c

IS21a

IS03b

0 1000 200030004000500060007000

BCE CE

0 1000 200030004000500060007000

BCE CE

IS02e






















3 579 135 113 1534 597 92 117 1083 583 19 114 2195 55 129 108 1397 54 85 106 8973 64 181 125 2274 63 161 124 1993 546 80 107 8514 739 79 145 1144 34 100 665 6685 497 95 973 9253 677 26 132 3376 44 101 868 883 35 84 686 5739 558 161 107 1713 457 40 868 347






2000300040005000A

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

Tim

Fenan 15

Wadi Fidan 4

Khirbat

Ora

Khi

Shiqmim

Hai-bar

Timna 39b

Yotvata EB

Timna 39b

Timna 39b

Timna 149s


Eilot quarry






0 1000 20001000ge

na 2

Timna 3

El-Furn

Timna 28

Jariya

Hill

rbat Hamra Ifdan

Tell Gerisa

Timna 30

Givat Yocheved


Tell Hara-Hadid

CEBCE

Yotvata Nabataean
















7 Conclusions











Acknowledgements



References






















































































































































29degN

30degN

31degN

32degN

33degN


Shiqmim

Ashkelon -Afridar

Tell Gerisa

Hai-bar

Timna 28

Timna 2

Beer Ora Hill

Timna 3

Timna 30

Tel Hara Hadid

Yotvata

Yotvata Fortress

Givat Yocheved

Eilot quarry

Timna 149

Timna 39b

Mitzpe Evrona

Fidan 4

Khirbat Jariya

Khirbat Nahas

Fenan 15

El-Furn


Khirbat Feinan

Fenan 1

Tell Dor










52 Results





















61 Timna 39b


Age

b

a


20

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

20

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

σ cutoff = 20

Syrian data

CALSK72


IS04b

IS05a

IS06bIS07a

IS14c

JS01c

JS02b

JS04b

JS05a

IS06a

IS08c

IS16a

JS01b

JS04a

JS08a

IS01aIS01b IS02a

IS02f

IS09aIS10e

IS11b

IS11d

IS11e

IS11i

IS15a

IS17a

IS19a

IS18a

IS20c

IS21a

IS03b

0 1000 200030004000500060007000

BCE CE

0 1000 200030004000500060007000

BCE CE

IS02e






















3 579 135 113 1534 597 92 117 1083 583 19 114 2195 55 129 108 1397 54 85 106 8973 64 181 125 2274 63 161 124 1993 546 80 107 8514 739 79 145 1144 34 100 665 6685 497 95 973 9253 677 26 132 3376 44 101 868 883 35 84 686 5739 558 161 107 1713 457 40 868 347






2000300040005000A

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

Tim

Fenan 15

Wadi Fidan 4

Khirbat

Ora

Khi

Shiqmim

Hai-bar

Timna 39b

Yotvata EB

Timna 39b

Timna 39b

Timna 149s


Eilot quarry






0 1000 20001000ge

na 2

Timna 3

El-Furn

Timna 28

Jariya

Hill

rbat Hamra Ifdan

Tell Gerisa

Timna 30

Givat Yocheved


Tell Hara-Hadid

CEBCE

Yotvata Nabataean
















7 Conclusions











Acknowledgements



References
































































































































61 Timna 39b


Age

b

a


20

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

20

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

σ cutoff = 20

Syrian data

CALSK72


IS04b

IS05a

IS06bIS07a

IS14c

JS01c

JS02b

JS04b

JS05a

IS06a

IS08c

IS16a

JS01b

JS04a

JS08a

IS01aIS01b IS02a

IS02f

IS09aIS10e

IS11b

IS11d

IS11e

IS11i

IS15a

IS17a

IS19a

IS18a

IS20c

IS21a

IS03b

0 1000 200030004000500060007000

BCE CE

0 1000 200030004000500060007000

BCE CE

IS02e






















3 579 135 113 1534 597 92 117 1083 583 19 114 2195 55 129 108 1397 54 85 106 8973 64 181 125 2274 63 161 124 1993 546 80 107 8514 739 79 145 1144 34 100 665 6685 497 95 973 9253 677 26 132 3376 44 101 868 883 35 84 686 5739 558 161 107 1713 457 40 868 347






2000300040005000A

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

Tim

Fenan 15

Wadi Fidan 4

Khirbat

Ora

Khi

Shiqmim

Hai-bar

Timna 39b

Yotvata EB

Timna 39b

Timna 39b

Timna 149s


Eilot quarry






0 1000 20001000ge

na 2

Timna 3

El-Furn

Timna 28

Jariya

Hill

rbat Hamra Ifdan

Tell Gerisa

Timna 30

Givat Yocheved


Tell Hara-Hadid

CEBCE

Yotvata Nabataean
















7 Conclusions











Acknowledgements



References














































































































Age

b

a


20

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

20

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

σ cutoff = 20

Syrian data

CALSK72


IS04b

IS05a

IS06bIS07a

IS14c

JS01c

JS02b

JS04b

JS05a

IS06a

IS08c

IS16a

JS01b

JS04a

JS08a

IS01aIS01b IS02a

IS02f

IS09aIS10e

IS11b

IS11d

IS11e

IS11i

IS15a

IS17a

IS19a

IS18a

IS20c

IS21a

IS03b

0 1000 200030004000500060007000

BCE CE

0 1000 200030004000500060007000

BCE CE

IS02e






















3 579 135 113 1534 597 92 117 1083 583 19 114 2195 55 129 108 1397 54 85 106 8973 64 181 125 2274 63 161 124 1993 546 80 107 8514 739 79 145 1144 34 100 665 6685 497 95 973 9253 677 26 132 3376 44 101 868 883 35 84 686 5739 558 161 107 1713 457 40 868 347






2000300040005000A

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

Tim

Fenan 15

Wadi Fidan 4

Khirbat

Ora

Khi

Shiqmim

Hai-bar

Timna 39b

Yotvata EB

Timna 39b

Timna 39b

Timna 149s


Eilot quarry






0 1000 20001000ge

na 2

Timna 3

El-Furn

Timna 28

Jariya

Hill

rbat Hamra Ifdan

Tell Gerisa

Timna 30

Givat Yocheved


Tell Hara-Hadid

CEBCE

Yotvata Nabataean
















7 Conclusions











Acknowledgements



References






























































































































3 579 135 113 1534 597 92 117 1083 583 19 114 2195 55 129 108 1397 54 85 106 8973 64 181 125 2274 63 161 124 1993 546 80 107 8514 739 79 145 1144 34 100 665 6685 497 95 973 9253 677 26 132 3376 44 101 868 883 35 84 686 5739 558 161 107 1713 457 40 868 347






2000300040005000A

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

Tim

Fenan 15

Wadi Fidan 4

Khirbat

Ora

Khi

Shiqmim

Hai-bar

Timna 39b

Yotvata EB

Timna 39b

Timna 39b

Timna 149s


Eilot quarry






0 1000 20001000ge

na 2

Timna 3

El-Furn

Timna 28

Jariya

Hill

rbat Hamra Ifdan

Tell Gerisa

Timna 30

Givat Yocheved


Tell Hara-Hadid

CEBCE

Yotvata Nabataean
















7 Conclusions











Acknowledgements



References


















































































































2000300040005000A

40

60

80

100

120

140

160

180

VA

DM

(Z

Am

2)

Tim

Fenan 15

Wadi Fidan 4

Khirbat

Ora

Khi

Shiqmim

Hai-bar

Timna 39b

Yotvata EB

Timna 39b

Timna 39b

Timna 149s


Eilot quarry






0 1000 20001000ge

na 2

Timna 3

El-Furn

Timna 28

Jariya

Hill

rbat Hamra Ifdan

Tell Gerisa

Timna 30

Givat Yocheved


Tell Hara-Hadid

CEBCE

Yotvata Nabataean
















7 Conclusions











Acknowledgements



References




























































































































7 Conclusions











Acknowledgements



References





















































































































Acknowledgements



References














































































































The Intensity of the Geomagnetic Field During the Last 6 Millennia as Recorded by Slag Deposits From...

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Transcript of The Intensity of the Geomagnetic Field During the Last 6 Millennia as Recorded by Slag Deposits From...