Heterogeneity, cyclicity and diagenesis in a Mississippian

brachiopod shell of palaeoequatorial Britain

Lucia Angiolini,1 Michael Stephenson,2 Melanie Leng,3 Flavio Jadoul,1 Dave Millward,4 AnthonyAldridge,5 Julian Andrews,6 Simon Chenery2 and Gareth Williams21Dipartimento Scienze della Terra �A. Desio� Via Mangiagalli 34, 20133 Milano, Italy; 2British Geological Survey, Keyworth, Nottingham,

NG12 5GG, UK; 3NERC Isotope Geosciences Laboratory, British Geological Survey, Keyworth, Nottingham, NG12 5GG, UK; 4British

Geological Survey, Murchison House, West Mains Road, Edinburgh EH9 3LA, UK; 5PO Box 19576, Woolston, Christchurch 8241, New

Zealand; 6School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, UK2

Introduction

Fossil shells are high-resolution ar-

chives which vary in response to

growth, environmental conditions

and diagenetic changes. Isotope pro-

files across growth lines of recent fossil

shells allow assessment of seasonality

(e.g. Schone et al., 2005; Johnson

et al., 2009). Only a handful of studies

have been conducted in the Palaeozoic

which relate isotope data and growth,

to unravel environmental variation

(Mii and Grossman, 1994; Ivany and

Runnegar, 2010). Fewer studies have

been undertaken on patterns of alter-

ation ⁄preservation and on the hetero-

geneous distribution of chemistry and

isotope composition within fossil

shells (e.g. Samtleben et al., 2001).

Brachiopods are excellent proxies

for ancient ocean conditions (e.g.

Compston, 1960; Popp et al., 1986;

Parkinson & Cusack in Williams

et al., 2007; Grossman et al., 2008),

because they record the primary sea-

water isotope composition with no

known vital effect in their innermost

shell layers. Also, brachiopod shells

grow episodically rather than contin-

uously, and major growth lines or

bands may form due to seasonal

perturbations (Hiller, 1988), making

them good recorders of past climate.

Recent studies show chemical hetero-

geneity in the shells of extant brachio-

pods (Cusack et al., 2008; Brand

et al., 2011), which reflects natural

environmental variation.

ABSTRACT

A shell of Gigantoproductus okensis shows twenty growth lines

with marked changes of fabric, indicating periodical reduction

of growth rates caused by environmental perturbations. The

number of growth lines suggests a lifespan of 20 years in

agreement with the survival rates of extant brachiopods, and

with spiral deviation analysis. Geochemical analyses across the

growth profile show a heterogeneous distribution of stable

isotopes and trace elements. It is possible to distinguish

primary from altered carbonate, and to interpret the isotopic

data. The oxygen isotope signal in the unaltered parts is

periodical and annual, with oscillation of �1.1&. The higher

values are at the growth lines (winter), and therefore most

likely related to monsoon circulation during the Visean. The

annual periodicity seems also present in the altered part of the

shell, suggesting that diagenesis could have reset the primary

values, but preserved their cyclicity.

Terra Nova, 00, 1–11, 2011

T E R 1 0 3 2 B Dispatch: 19.10.11 Journal: TER CE: Bharani

Journal Name Manuscript No. Author Received: No. of pages: 11 PE: Revathi

Sheffield

Derby

Buxton

Stoke-

on-

Trent

Bakewell

Chapel

En Le

Frith

Matlock

Permian & Triassic

Peak limestone group (Visean)

Millstone grit group (Serpukhovian-Bashkirian)

Pennine coal measures group (Bashkirian- Moscovian)

10 km Sample site

Fig. 1 Geological map of the Carboniferous rocks of the Derbyshire High region of

central England. The Monsal Dale Limestone Formation is part of the Peak

Limestone Group. The star indicates the sample location.

Correspondence: Lucia Angiolini, Diparti-

mento Scienze della Terra �A. Desio� Via

Mangiagalli 34, 20133 Milano, Italy.

e-mail: lucia.angiolini@unimi.it3

� 2011 Blackwell Publishing Ltd 1

doi: 10.1111/j.1365-3121.2011.01032.x

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

Herein we present the geochemistry

of a Mississippian brachiopod shell

from palaeoequatorial Britain and

show relationships with growth, envi-

ronmental change and diagenesis.

Material and methods

The specimen is a productid brachio-

pod of the species Gigantoproductus

okensis (Sarytcheva) (CA6866, BGS

collection) from Monsal Dale Lime-

stone Formation of Derbyshire, UK

(Bridges, 1982) of early Brigantian D2

(= late Visean) age (Fig. 1). The

specimen was sectioned parallel to

growth and screened by SEM,

cathodoluminescence and trace ele-

ment analysis. One hundred and four-

teen samples were taken using a

0.5 mm drill across the growth lines

for geochemistry and isotopes. Subs-

amples for geochemical analysis were

dissolved in a few ml of 1 M ultra-pure

acetic acid, taken up in 1% (c. 0.16 M)

nitric acid, and measured for Mn, Sr

and Fe using Inductively Coupled

Plasma-Atomic Emission Spectros-

copy (ICP-AES) on a Fison ⁄ARL

3580 simultaneous ⁄ sequential spec-

trometer. The instrument was cali-

brated with NIST solutions and

precision is >10%.

Trace elements were also measured

along a transverse section of the shell

in situ using a New Wave Research

213 nm Nd-YAG laser ablation (LA)

system attached to a Thermo X Series

ICPMS. The laser was optimized and

calibrated with the NIST 610 silicate

glass. Laser ablation pits were then

cross correlated with the samples

drilled for geochemistry and isotopes;

each drilled hole corresponded to 2–4

LA-ICPMS pits.

Isotope analysis was undertaken

using a GV IsoPrime mass spectro-

meter with Multiprep device. Isotope

values (d13C, d18O) are reported as per

mil (&) deviations of the isotopic

ratios (13C ⁄12C, 18O ⁄

16O) calculated

to the VPDB scale using a within-run

laboratory standard (KMC) cali-

brated against international NBS

standards (NBS18 and 19). Analytical

reproducibility was better than 0.1&

for d13C and d18O.

Fourier analysis was carried out on

O and C time series data of sequen-

tially collected sample numbers 40–97

to investigate periodicity. Samples

which are out of sequence of growth

because they either represent the

same growth increment or a time

reversal were not considered. Spectral

analysis of unevenly sampled data is

frequently achieved by interpolating

data to a uniform scale, which can

have the undesirable consequence of

aliasing high frequencies into the low

frequencies of a spectrum. Lomb

(1976) and Scargle (1989) modified

the traditional Fourier transform to

account for the effects of uneven time

sampling. This study adopts the pro-

cedure of Schulz and Stattegger

(1997).

Twenty years growth of the shell

Gigantoproductid brachiopods are

abundant in the upper Visean shallow

marine bioclastic limestones of central

England (Ferguson, 1978; Pattison,

1981; Bridges, 1982). These brachio-

pods lived semi-infaunally in coarse

sediments, stabilized by their extended

ears and postero-ventral shell thicken-

ing, in normal saline marine settings.

The large size and thick shell of

Gigantoproductus okensis (Sarytcheva)

(Fig. 2) make it suitable for analysis

of shell growth, structure and geo-

chemical composition. In longitudinal

section (Fig. 3), it shows conspicuous

growth lines indicating slowing of

growth caused by regular environmen-

tal perturbations. Twenty major

growth lines cross the well-preserved

prismatic shell layer of the ventral

valve and are weakly inclined anteri-

orly towards the inner shell surface.

At the growth lines, the fabric changes

from calcite prisms to irregular lami-

nae (Fig. 4), confirming periodical

mantle-reversal and reduction of

growth rate. The spacing of the

growth lines varies from 300 lm to

more than 1 mm (c.f. Mii et al., 2001).

According to Hiller (1988) a seasonalFig. 3 Longitudinal section through Gigantoproductus okensis. The shell is orientated

with dorsal valve up and the umbo to the right.

Fig. 2 Ventral view of an articulated specimen of Gigantoproductus okensis. Maxi-

mum width = 15.6 cm, length = 12.1 cm.

Heterogeneity, cyclicity and diagenesis 1• L. Angiolini et al. Terra Nova, Vol 00, No. 0, 1–11

.............................................................................................................................................................

2 � 2011 Blackwell Publishing Ltd

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

fall in temperature ⁄nutrient supply

(winter) would reduce or stop growth

causing a change in the direction of

the axes of the secondary layer fibres

or a halt in the growth of regularly

stacked tertiary prisms.

There are few controlled growth

studies in extant brachiopods (Buen-

ing, 2001), but estimates suggest a

lifespan of 3–20 years (Buening and

Spero, 1996). Recent Tyrrhenian Sea

brachiopods have a lifespan

>40 years (Taddei Ruggiero, 2001).

The growth lines in our specimen

suggest a lifespan of at least 20 years

in agreement with these estimates.

To further constrain the age of our

brachiopod we used spiral deviation

analysis, which studies deviations

from the secular component of accre-

tionary growth of the shells (Aldridge

and Gaspard, 2011). Logarithmic spi-

rals were fitted to the inner ventral

valve surface of our shell (Aldridge,

1999) with deviations from spiral fit

analysed for periodicity. Deviations

were nonrandom (P < 0.01 4, mean

square successive difference test,

Bissell and Williamson, 1988), and

subjected to an empirical mode

decomposition (Wu et al., 2007;

implemented as R code by Donghoh

and Hee-Seok, 2008). The first four

minima of an empirical mode function

(Fig. 5) represented distances from the

umbo that were then located on the

actual shell. Two internal growth lines

were discerned between each of the

first four minima of spiral deviations,

which were then interpreted as 2-year

increments. The indicated age at the

first four minima, their arc length

from umbo, and a 100 unit maximum

length were used to fit a two para-

meter logistic growth function

(Fig. 6). Age at death was inversely

calculated from the fitted logistic

curve to be 20.2 years, which is con-

sistent with the age estimated by

counting the growth lines.

Geochemistry and preservation of the

accretionary shell

One hundred and fourteen samples

(for O and C isotopes and trace

elements) were taken across the

20 year period of growth within the

mostly non- or slightly luminescent

(indicative of low alteration, e.g. Popp

et al., 1986; Grossman et al., 1993)

parts of the shell interior, which con-

sists of a well developed prismatic

layer (Figs 4, 7 and 8 and Table 1).

The samples typically show Sr

>1000 ppm, Mg >3000 ppm, Na

�1000 ppm, Mn �60 ppm and Fe

<300 ppm, with a heterogeneous dis-

tribution throughout the shell. Trace

elements are consistent with data from

extant species (Brand et al., 2003) and

from well-preserved Carboniferous

and Permian brachiopods (Bruckshen

et al., 1999; Korte et al., 2003; Van

Geldern et al., 2006); their hetero-

geneous distribution reflects the natu-

ral variations observed in recent

brachiopods (Cusack et al., 2008;

Fig. 4 Ultrastructure of the shell at the growth lines showing a change in fabric at the

growth halts from stacked prisms to irregular laminae.

Fig. 5 Deviations from spiral growth as

an empirical mode function plotted

against distance from ventral umbo

(maximum shell length fixed at 100

units). Solid symbols denote the minima

used in fitting the two parameter logistic

growth curve.

Fig. 6 Logistic growth curve fitted to

distance and age of four minima identi-

fied from spiral deviations (Fig. 5). The

solid square symbol locates the length of

the inner ventral valve (98.85 image

units) and the calculated age at death

(20.2 years).

Colouronline,B&W

inprint

Terra Nova, Vol 00, No. 0, 1–11 L. Angiolini et al. • Heterogeneity, cyclicity and diagenesis 1

.............................................................................................................................................................

� 2011 Blackwell Publishing Ltd 3

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

Brand et al., 2011). Except for small

areas, the non-luminescent or slightly

luminescent inner prismatic shell has

d18O varying from )4.4& to )6.4&

and d13C from )2.6& to +1.3&.

There are a few values in common

with those of Popp (1986) who inves-

tigated Gigantoproductus of the As-

bian-Brigantian of Britain and

Belgium. Popp�s (1986) data came

from spot-analysis on material which

was either undetermined at specific

level or belongs to different species of

the genus, and thus may be influenced

by heterogeneous distribution of TE

in the shell, and interspecific variation.

In the luminescent parts, which are

characterized by diagenetic quartz

replacing original calcite, d18O values

are very low ()11.9& to )7&). The

quartz is in the form of small idio-

morphic crystals or, more frequently,

as mm-sized aggregations of idiomor-

phic ⁄ subidiomorphic crystals and par-

tially silicified nuclei with calcitic

inclusions (Fig. 9). These very low

d18O values are coupled with high

d13C values, and so are not indicative

of early diagenetic alteration related

to sub aerial exposure (Bridges, 1982).

Also d13C values do not fit the �mete-

oric calcite line� (Lohmann, 1988).

Luminescent samples (e.g. samples 5–

38; 65–71; Table 1) show Na, Mg and

Sr lower than the unaltered material,

but higher Fe; Mn is generally low.

Samples at the anterior margin of the

shell (samples 86–92) have relatively

low Mg and Sr, but higher Mn and

Fe; these trace elements suggest alter-

ation, although the d18O values for

these samples are in the range of those

from the unaltered shell material or

only slightly lower. This suggests a

different type of alteration affecting

the posterior part of the shell with

respect to the anterior margin, prob-

ably related to the occurrence of voids

in the umbonal cavity, later filled by

equant calcite (Fig. 3).

In addition, trace element variabil-

ity through a transverse section of the

shell (from the inside to outside edge

of the shell between sample positions

46–47 of the series shown in Fig. 7)

was measured using laser ablation to

investigate the change from the inner

unaltered to the outer altered portions

of the shell (Tables 2 and 3). Diage-

netic alteration in the outer shell is

identified by d18O values lower than

)6.4&, generally lower Sr and higher

Mn. This suggests that the fossil

retains primary material within the

inner most part of the shell. Alteration

of the posterior, anterior and external

part of the shell may have been caused

by locally confined circulation of rel-

atively hot fluids of hydrothermal

origin, since the region was affected

by Mississippi-Valley type Late Car-

boniferous-Early Permian mineraliza-

tion with fluid temperatures of

100 �C–150 �C (Kendrick et al., 2002).

The central inner part of the shell may

Fig. 7 Plane-polarized light (below) and corresponding CL images (above) of the

ventral valve of Gigantoproductus okensis, umbo to the right. The shell is luminescent

around quartz aggregates (left side) and along the external margin. Numbers indicate

samples 26–97 (Table 1).

Fig. 8 Non-luminescent shell interior (external part of the shell bottom down), transmitted light and CL.

Colouronline,B&W

inprint

Colouronline,B&W

inprint

Heterogeneity, cyclicity and diagenesis 1• L. Angiolini et al. Terra Nova, Vol 00, No. 0, 1–11

.............................................................................................................................................................

4 � 2011 Blackwell Publishing Ltd

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

Table 1 Isotopes and trace elements for the samples collected along the internal surface of the shell.

Sample no. d13C (&) d

18O (&) SEM CL Ca lg ⁄g Mg lg ⁄g Ba lg ⁄g Sr lg ⁄g Mn lg ⁄g Fe lg ⁄g

1 1.1 )5.2 P III

2 0.7 )6.0 P III

3 0.1 )6.5 P III

4 0.9 )6.1 P III

5 0.9 )7.3 P III

6 1.1 )7.4 P III

7 0.8 )8.2 P III

8 0.6 )8.9 P III

9 0.4 )10.5 P III

10 0.4 )11.9 P III 400 000 2884 <DL 534 131 <DL

11 0.6 )11.8 P III

12 0.7 )11.9 P III

13 0.1 )11.7 P III 400 000 2530 <DL 515 111 <DL

14 )0.1 )11.9 P III 400 000 2393 <DL 540 107 <DL

15 )0.2 )11.5 P III

16 0.1 )11.4 P III

17 0.0 )11.6 P III

18 0.3 )11.7 P III

19 0.2 )11.4 P III 400 000 2453 <DL 393 141 <DL

20 0.4 )11.3 P III L 400 000 2332 <DL 413 136 <DL

21 0.1 )11.3 P III L

22 0.2 )11.4 P III L 400 000 2234 <DL 541 130 <DL

23 )0.5 )10.6 P III L 400 000 2208 <DL 628 136 <DL

24 )0.4 )10.6 P III L

25 )0.4 )10.9 P III L

26 )0.1 )11.1 P III L

27 )0.5 )10.6 P III L

28 )0.7 )9.9 P III L

29 )1.5 )7.6 P III L

30 )1.9 )7.8 P III L

31 )0.5 )10.2 P III L

32 )0.4 )9.8 P III L

33 )0.8 )9.0 P III L

34 )1.2 )9.3 P III L

35 )1.5 )9.2 P III L

36 )0.5 )10.5 P III L

37 )0.4 )10.8 P III L

38 )1.7 )7.5 P III SL

39 )2.2 )6.4 P III NL 400 000 4719 <DL 1338 15 <DL

40 )1.5 )5.9 P III NL

41 )1.5 )5.6 P III NL 400 000 4566 <DL 1288 <DL <DL

42 )0.4 )5.3 P III NL 400 000 4044 <DL 1228 <DL <DL

43 0.3 )4.9 P III NL 400 000 4214 <DL 1274 9 <DL

44 )0.8 )5.1 P III NL 400 000 4192 <DL 1289 <DL <DL

45 )1.3 )5.6 P III NL 400 000 3459 <DL 1201 19 <DL

46 )1.2 )5.7 P III NL 400 000 3529 <DL 1249 <DL <DL

47 )0.3 )5.5 P III NL 400 000 3477 <DL 998 <DL <DL

48 )0.5 )5.5 P III NL 400 000 3636 <DL 1111 36 <DL

49 )0.9 )5.4 P III NL

50 )0.3 )9.2 P III SL

51 0.8 )10.4 P III L

52 )0.6 )5.5 P III NL

53 )0.3 )4.9 P III NL

54 )1.5 )5.5 P III NL

55 )1.5 )5.2 P III NL 400 000 3432 <DL 1168 69 <DL

56 0.2 )4.8 P III NL 400 000 3154 <DL 996 86 157

57 )1.3 )5.0 P III NL 400 000 3467 <DL 1175 28 <DL

58 )0.4 )4.7 P III NL

59 )0.5 )4.4 P III NL 400 000 2581 <DL 793 195 <DL

60 )2.5 )5.8 P III NL 400 000 3531 <DL 1187 29 <DL

61 )2.6 )6.0 P III NL 400 000 3822 <DL 1228 <DL <DL

Terra Nova, Vol 00, No. 0, 1–11 L. Angiolini et al. • Heterogeneity, cyclicity and diagenesis 1

.............................................................................................................................................................

� 2011 Blackwell Publishing Ltd 5

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

Table 1 Continued

Sample no. d13C (&) d

18O (&) SEM CL Ca lg ⁄g Mg lg ⁄g Ba lg ⁄g Sr lg ⁄g Mn lg ⁄g Fe lg ⁄g

62 )2.2 )6.0 P III NL 400 000 3735 <DL 1219 41 <DL

63 )2.6 )5.9 P III NL 400 000 3856 <DL 1273 54 <DL

64 )2.4 )6.2 P III NL 400 000 3873 <DL 1268 33 <DL

65 0.1 )7.9 P III L 400 000 3192 <DL 918 48 <DL

66 0.1 )10.5 P III L

67 0.1 )8.5 P III SL

68 )0.7 )7.0 P III SL

69 )0.6 )7.0 P III SL

70 0.3 )9.7 P III SL

71 0.4 )9.9 P III L

71.5 )0.4 )7.9 P III L

72 0.0 )6.2 P III SL 400 000 3178 <DL 889 152 279

72.5 )1.1 )6.3 P III SL

73 )1.0 )5.8 P III SL

73.5 )0.9 )6.4 P III SL

74 )1.4 )6.1 P III NL 400 000 3648 <DL 1120 46 <DL

74.5 )0.9 )5.7 P III NL

75 )1.0 )6.2 P III NL 400 000 3525 <DL 1043 101 85

75.5 )2.1 )8.2 P III NL

76 )1.3 )5.9 P III NL 400 000 3924 <DL 1115 55 646

76.5 )1.1 )6.1 P III NL

77 )1.1 )6.0 P III NL 400 000 3766 <DL 1090 82 85

78 )0.7 )6.5 P III SL 400 000 3225 <DL 917 130 239

79 )0.5 )6.3 P III SL 400 000 2701 <DL 733 214 338

80 0.2 )6.5 P III NL

81 0.2 )6.4 P III NL 400 000 3194 <DL 852 123 356

82 0.2 )6.0 P III NL

83 0.6 )6.2 P III SL 400 000 2827 <DL 722 149 439

84 0.9 )7.3 P III L

85 0.5 )7.0 P III L

86 0.8 )6.1 P III L 400 000 2054 <DL 442 328 918

87 1.2 )5.9 P III L 400 000 1972 <DL 399 454 954

87.5 0.8 )6.8 P III L

88 1.1 )6.4 P III L 400 000 1567 <DL 310 548 872

88.5 +1.0 )8.2 P III L

89 1.2 )6.2 P III L 400 000 1754 <DL 374 516 965

89.5 1.0 )5.8 P III L

90 1.0 )6.5 P III L 400 000 1993 <DL 463 405 785

90.5 1.0 )6.4 P III L

91 1.1 )6.2 P III L

91.5 1.1 )7.1 P III L

92 1.0 )6.3 P III SL 400 000 2149 <DL 567 191 225

92.5 1.1 )6.2 P III SL

93 0.9 )7.3 P III SL 400 000 1760 <DL 448 254 233

93.5 1.3 )7.0 P III SL

94 1.3 )6.5 P III NL 400 000 1961 <DL <DL <DL <DL

94.5 1.3 )6.2 P III SL

95 1.3 )6.2 P III SL

95.5 1.3 )6.9 P III SL

96 1.4 )6.9 P III L

96.5 1.2 )7.0 P III L

97 1.3 )7.0 PII ⁄ III L

97.5 1.2 )7.7 PII ⁄ III L

Equant calcite 0.1 )8.4

Calcite cement 0.1 )8.2

Calcite cement 0.4 )12.1

Echinoderm 1 2.1 )8.3

Echinoderm 2 2.0 )6.1

Peloidal packstone 3.0 )4.9

Equant calcite inside the posterior filling of the shell. Calcite cements outside the shell. Echinoderm in the matrix outside the shell. Peloidal packstone in the

anterior geopetal filling of the shell. SEM ultrastructure: PIII = preserved tertiary layer, PII ⁄ III = preserved secondary ⁄ tertiary layers. CL, cathodolumi-

nescence; DL, detection limit; L, luminescent; NL, non-luminescent; SL, (dull orange) slightly luminescent.

Heterogeneity, cyclicity and diagenesis 1• L. Angiolini et al. Terra Nova, Vol 00, No. 0, 1–11

.............................................................................................................................................................

6 � 2011 Blackwell Publishing Ltd

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

have been protected from diagenetic

fluids, being in the shadow of the

convex ventral valve.

Analyses of the matrix of the sam-

ple (Table 1) show that the d18O

values of the equant calcite filling the

umbo and the Mg-calcite of associated

echinoderm fragments are lower than

those of unaltered brachiopod shell.

Is the geochemical record of the

accretionary growth periodical?

Not only is shell growth periodical,

but also regular oscillations of d18O

and d13C occur (Table 1 and Fig. 10).

d18O varies more regularly than d13C,

as has been previously observed in the

Lower Permian bivalve Eurydesma

cordatum (Ivany and Runnegar,

2010). If the growth lines represent

halts in the growth of the tertiary layer

during a seasonal fall in temperature

and ⁄or nutrient supply, the oscillation

of d18O can be tested against their

pattern. Considering only possibly

unaltered values, d18O is higher when

the sample coincides with a growth

line, whereas lower values occur in the

tertiary layer between growth lines

(Figs 10 and 11). This suggests that

growth lines represent winter halt of

growth as higher d18O values corre-

spond to lower sea temperature. As

the average oscillation of d18O is

about 1.1&, the sea surface tempera-

ture (SST) variation may have been

�5 �C (using )0.24& ⁄ �C after Craig,

1965). However, as there are still

many uncertainties about the isotopic

composition of Palaeozoic seawater

(e.g. Muehlenbachs and Clayton,

1976; Veizer et al., 1999; Came et al.,

2007; Ivany and Runnegar, 2010), we

cannot interpret absolute tempera-

tures.

To test the oscillation of the d18O

data we applied Fourier transform

analysis to the sequence of altered and

unaltered samples 40–97, which were

sampled sequentially to record up

to 230 month�s growth (Table 4

and Fig. 4). Following Schulz and

Fig. 9 Local diagenetic replacement of calcite by authigenic quartz. The authigenic quartz are subhedral crystal aggregates, mm-

sized, with the original calcareous shell at the nuclei. Transmitted ⁄polarized light and CL.

Table 2 Comparison of trace element data by LA-ICPMS (University of East Anglia)

and ICP (British Geological Survey) on different low luminescent parts of the shell.

n Na lg ⁄g Mg lg ⁄g Sr lg ⁄g Mn lg ⁄g Fe lg ⁄g

LA-ICPMS

(corrected) UEA

8 937 2868 1055 67 354

ICP BGS 25 na 3670 1135 65 249

Colouronline,B&W

inprint

Terra Nova, Vol 00, No. 0, 1–11 L. Angiolini et al. • Heterogeneity, cyclicity and diagenesis 1

.............................................................................................................................................................

� 2011 Blackwell Publishing Ltd 7

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

Stattegger (1997), we computed a

power spectrum (Fig. 12), which

shows peaks at 0.91, 1.602 and

2.83 years. Regression (least squares)

of sine and cosine terms for part of the

data sequence with a high sampling

rate confirmed that the 0.91 year cycle

is significant (F = 4.53 on 2, 23 d.f.;

P = 0.02) and consistent with a

12 month cycle (Fig. 13). Fourier

analysis on the altered and unaltered

parts seems thus to show that d18O

periodicity is annual and thus sea-

sonal, although other interannual

periodicity is also present (Fig. 12).

Carbon and oxygen isotopes

–2.0

–4.0

–6.0

–8.0

–10.0

–12.0

0.0

2.020 40 60 80 100

δ13C

an

d

18O

13C

18O

Fig. 10 d18O and d13C data for Gigantoproductus okensis. Numbers on the x-axis

represent samples from the umbo (0) to the anterior margin (97). The shell was

originally sampled sequentially at 97 points across growth lines; the shell was

subsequently re-sampled (between 71–77 and 87–97) to obtain 114 data points in total

(Table 1). Shading on the d18O plot shows altered parts of the shell based on CL, TE

and d18O values <)6.4&. The position of the growth lines relative to the isotopic

data is shown by the vertical dotted lines for samples which are in order of growth.

Table 3 Data table for the transverse section. Depth scale is in microns from the

inside edge of the shell where 0 = sample 1.

Depth (lm) Na lg ⁄g Mg lg ⁄g Mn lg ⁄g Fe lg ⁄g Sr lg ⁄g d18O& d

13C&

0 1587 2339 58 85 979 )5.24 0.92

200 1034 2607 116 77 978 )5.24 0.92

400 637 2990 56 357 1160 )5.24 0.92

600 750 3521 68 481 903 )5.30 )1.12

800 751 2634 110 764 919 )5.30 )1.12

1000 929 2523 56 435 1089 )5.30 )1.12

1200 657 3009 47 376 1162 )6.23 )1.74

1400 1150 3321 26 258 1250 )6.23 )1.74

1600 1177 3365 11 51 1185 )6.23 )1.74

1800 639 3517 51 175 1106 )7.25 )1.02

2000 230 2780 105 168 1082 )7.25 )1.02

2200 117 2190 165 220 828 )7.25 )1.02

2400 725 2411 134 140 893 )7.25 )1.02

2600 1490 3027 85 145 1019 )9.81 )0.54

2800 2162 3904 23 181 1149 )9.81 )0.54

3000 2252 4091 18 56 1296 )9.81 )0.54

3200 1090 2510 88 48 832 )10.30 )0.09

3400 252 3130 130 466 793 )10.30 )0.09

3600 81 2257 219 278 583 )10.69 )0.36

3800 )49 2389 138 204 660 )10.69 )0.36

4000 242 1721 350 545 497 )10.74 0.18

4200 218 1646 416 557 530 )10.74 0.18

4400 562 1872 24 36 700 )7.79 )0.28

4600 1285 2093 78 130 718 )7.79 )0.28

4800 452 1492 240 765 633 )6.49 0.39

5000 820 1269 259 687 478 )6.49 0.39

Table 4 Estimates of the age (expressed

in months) of sample points 40–97

considering their position with respect

to growth lines. Out of sequence of

growth samples have been excluded.

d13C d18O

1.3 )7.0 97 5 months

1.4 )6.9 96 9 months

1.3 )6.2 95 11 months

1.3 )6.5 94 16 months

0.9 )7.3 93 20 months

1.0 )6.3 92 22 months

1.1 )6.2 91 23 months

1.0 )6.5 90 27 months

1.2 )6.2 89 30 months

1.1 )6.4 88 34 months

1.2 )5.9 87 35 months

0.8 )6.1 86 37 months

0.5 )7.0 85 39 months

0.9 )7.3 84 42 months

0.6 )6.2 83 44 months

0.2 )6.0 82 46 months

0.2 )6.4 81 47 months

0.2 )6.5 80 49 months

)0.5 )6.3 79 53 months

)0.7 )6.5 78 56 months

)1.1 )6.0 77 58 months

)1.3 )5.9 76 59 months

)1.0 )6.2 75 61 months

)1.4 )6.1 74 66 months

)1.0 )5.8 73 71 months

0.0 )6.2 72 78 months

0.3 )9.7 70 85 months

)0.6 )7.0 69 90 months

)0.7 )7.0 68 95 months

0.1 )8.5 67 107 months

)2.6 )5.9 63 119 months

)2.2 )6.0 62 122 months

)2.6 )6.0 61 125 months

)2.5 )5.8 60 129 months

)0.5 )4.4 59 131 months

)0.4 )4.7 58 134 months

)1.3 )5.0 57 138 months

0.2 )4.8 56 143 months

)1.5 )5.2 55 160 months

)0.3 )4.9 53 167 months

)0.6 )5.5 52 179 months

0.8 )10.4 51 181 months

)0.3 )9.2 50 186 months

)0.9 )5.4 49 191 months

)0.5 )5.5 48 197 months

)0.3 )5.5 47 203 months

)1.2 )5.7 46 210 months

)0.8 )5.1 44 213 months

0.3 )4.9 43 218 months

)1.5 )5.6 41 222 months

)1.5 )5.9 40 225 months

)0.4 )5.3 42 230 months

Colouronline,B&W

inprint

Heterogeneity, cyclicity and diagenesis 1• L. Angiolini et al. Terra Nova, Vol 00, No. 0, 1–11

.............................................................................................................................................................

8 � 2011 Blackwell Publishing Ltd

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

These periodicities may have been

caused by a seasonal climate affecting

palaeoequatorial Britain in the late

Mississippian (Scotese and McKer-

row, 1990). Indeed, monsoon rainfall

seasonality at this time has already

been deduced from palaeosols

(Wright, 1990) and fossil plant mor-

phology (Falcon-Lang, 1999). Also

Tucker et al. (2009) reported d18O

cyclicity in the Pendlelian Great Lime-

stone, interpreted as arid–humid

climate cycles.

Can a primary chemical and isotopic

signal be retained even after

diagenesis?

Both the raw data presented in Fig. 10

and the Fourier analysis (Figs 12 and

13) show that the annual periodicity

seems to be preserved as a residual

signal within the altered parts of the

shell, suggesting that cyclicity, if not

primary values, were retained when

diagenetic fluids locally permeated the

shell. d18O is systematically lower by

4–6&, but has the same periodicity in

the primary portion (inner shell) and

in the altered parts of the posterior,

anterior and external shell. Preserva-

tion of the original isotopic signal is

more common in carbon isotope data,

as the amount of C in the rock buffers

secondary C introduced within the

diagenetic fluid (Tucker, 1990; Sharp,

2007). Similar data on preserved iso-

tope cyclicity have been shown by

Rasser and Fenninger (2002), Valen-

cio et al. (2003), and Tucker et al.

(2009) though over a longer (millen-

nial) time-scale and with large rock

mass involved. This mechanism for

signal preservation in diagenetic rocks

is however, not fully understood.

Conclusions

This study reveals periodical variation

in growth and geochemistry of a

brachiopod shell, which may have

been linked to a seasonal climate, as

indicated by other proxies (e.g.

Wright, 1990; Falcon-Lang, 1999;

Tucker et al., 2009). The evidence

suggests that great variation in pres-

ervation ⁄alteration, as well as physical

and geochemical features can be seen

in a single shell, suggesting caution in

the interpretation of isotopic data

derived from spot-analyses, especially

in fossil shells. We also show that even

in diagenetically altered parts of the

shell, primary periodicity signals can

be preserved, even if primary values

are not. Thus, the results of the studyFourier transform analysis

0

0.5

1

1.5

2

2.5

3

3.5

0 1 2 3 4

Periodicity/frequency

Po

we

r/str

en

gth

of

pe

rio

dic

ity

Fig. 12 Power spectrum of the d18O time

series (Table 4) with signal peaks at 0.91,

1.602 and 2.83 years. The input data had

a maximum, minimum and mean sample

rate of 1.42, 0.08 and 0.37 years respec-

tively. At mean sampling rate, the Sam-

pling Theorem predicts a resolution of

0.74 cycles ⁄year, which is less than the

cycle of 0.91 years. Application of the

Siegel Test (Schulz and Stattegger, 1997)

was significant (P < 0.05) rejecting the

null hypothesis of white noise (random

variation) for the alternative of at least

three spectrum peaks.

Fig. 13 d18O values for altered (solid round symbols) and unaltered (solid square

symbols) densely sampled locations from umbo to the median part of the shell. Fitted

sine and cosine regression with a trend (continuous line) confirms the yearly cycle

(F = 4.53 on 2, 23 df; P = 0.02) and is consistent with a 12-month cycle both for

altered and unaltered samples.

–7.9 –6.2–5.9

–6.0–6.0

–5.8–4.4 –4.7 –4.8 –4.9–5.0

–5.2–5.5

–5.5–10.8 –9.2

–5.4

–5.5–5.7

1 mm

Fig. 11 Distribution of d18O data with respect to growth lines in the central part of the shell (data points 45–65). Bold italicized

numbers represent unaltered d18O data sampled at the growth lines, regular numbers represent unaltered d18O data sampled in the

growth increment and underlined numbers represent altered d18O data. Samples 65–67 represent a time reversal and they have not

been considered in the Fourier analysis (Table 4).

Colouronline,B&W

inprint

Terra Nova, Vol 00, No. 0, 1–11 L. Angiolini et al. • Heterogeneity, cyclicity and diagenesis 1

.............................................................................................................................................................

� 2011 Blackwell Publishing Ltd 9

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

may have implications for under-

standing Palaeozoic climate dynamics

and far-reaching effects for isotope

proxy studies in general.

Acknowledgements

We are grateful to C. Malinverno and A.

Rizzi for sample preparation and SEM

assistance. Hilary Sloane at NIGL under-

took the stable isotope analysis. This

research was funded by the British Geo-

logical Survey. Stephenson, Leng, Mill-

ward and Williams publish this article

with the permission of the Director British

Geological Survey (NERC). This paper

benefitted from insightful reviews by Ethan

Grossman, the Editor and Associated Edi-

tors of Terre Nova and an anonymous

reviewer.

References

Aldridge, A.E., 1999. Brachiopod outline

and episodic growth. Paleobiology, 25,

471–482.6

Aldridge, A.E. and Gaspard, D., 2011.

Brachiopod life histories from spiral

deviations in shell shape and micro-

structural signature – preliminary report.

Memoirs of the Association of Austral-

asian Palaeontologists, 41, 257–268.

Bissell, A.F. and Williamson, R.J., 1988.

Successive difference tests – theory and

interpretation. J. Appl. Stat., 15, 305–323.

Brand, U., Logan, A., Hiller, N. and

Richardson, J., 2003. Geochemistry of

modern brachiopods: applications and

implications for oceanography and

paleoceanography. Chem. Geol., 198,

305–334.

Brand, U., Logan, A., Bitner, M.A.,

Griesshaber, E., Azmy, K. and Buhl, D.,

2011. What is the ideal proxy of Paleo-

zoic seawater chemistry? Memoirs of the

Association of Australasian Palaeontolo-

gists, 41, 9–24.

Bridges, H., 1982. The origin of cyclothems

in the Late Dinantian platform carbon-

ates at Crich Derbyshire. Proc. Yorkshire

Geol. Soc., 44, 150–180.

Bruckshen, P., Oesmann, S. and Veizer, J.,

1999. Isotope stratigraphy of the Euro-

pean Carboniferous. Proxy signals for

ocean chemistry, climate and tectonics.

Chem. Geol., 161, 127–163.

Buening, N., 2001. Brachiopod shells: re-

corder of the present and keys to the

past. Paleontol Soc Papers, 7, 117–143.

Buening, N. and Spero, H.J., 1996. Oxygen

and carbon isotope analyses of the

articulate brachiopod Laqueus californi-

anus: a recorder of environmental chan-

ges in the subeuphotic zone. Mar. Biol.,

127, 105–114.

Came, R.E., Eiler, J.M., Veizer, J., Zmy,

K., Brand, U. and Weidman, C.R., 2007.

Coupling of surface temperatures and

atmospheric CO2 concentrations during

the Palaeozoic era. Nature, 449, 198–201.

Compston, W., 1960. The carbon isotopic

composition of certain marine inverte-

brates and coals from the Australian

Permian. Geoch. Cosmoch. Acta, 18, 1–

22.

Craig, H., 1965. The measurement of oxy-

gen isotope palaeotemperatures. In:

Stable Isotopes in Oceanographic Studies

and Palaeotemperatures (E. Tongiorgi,

ed.), pp. 161–182. Consiglio Nazionale

delle Ricerche Laboratorio di Geologia

Nucleare, Pisa.

Cusack, M., Parkinson, D., Perez-Huerta,

A., England, J., Curry, G.B. and Fallick,

A.E., 2008. Relationship between d18O

and minor element composition of

Terebratalia transversa. Earth and

Environmental Science Transactions of

the Royal Society of Edinburgh, 98,

439–445.

Donghoh, K. and Hee-Seok, O., 2008.

EMD: empirical mode decomposition

and hilbert spectral analysis. Available

at: http://cran.r-project.org.

Falcon-Lang, H.J., 1999. The Early

Carboniferous (Courceyan-Arundian)

monsoonal climate of the British Isles:

evidence from growth rings in fossil

woods. Geol. Mag., 136, 177–187.

Ferguson, J., 1978. Some aspects of the

ecology and growth of the Carbonifer-

ous Gigantoproductids. Proc. Yorkshire

Geol. Soc., 42, 41–54.

Grossman, E.L., Mii, H.S. and Yancey,

T.E., 1993. Stable isotopes in late Penn-

sylvanian brachiopods from the United

States: implications for Carboniferous

paleoceanography. Geol. Soc. Am. Bull.,

105, 1284–1296.

Grossman, E.L., Yancey, T.E., Jones, T.E.,

Bruckschen, P., Chuvashov, B., Maz-

zullo, S.J. and Mii, H.S., 2008. Glacia-

tion, aridification, and carbon

sequestration in the Permo-Carbonifer-

ous: the isotopic record from low lati-

tude. Palaeogeogr. Palaeoclimatol.

Palaeoecol., 268, 222–233.

Hiller, N., 1988. The development of

growth lines on articulate brachiopods.

Lethaia, 21, 177–188.

Ivany, L.C. and Runnegar, B., 2010. Early

Permian seasonality from bivalve d18O

and implications for the oxygen isotopic

composition of seawater. Geology, 38,

1027–1030.

Johnson, A.L.A, Hickson, J.A., Bird, A.,

Schone, B.R., Balson, P.S., Heaton,

T.H.E. and Williams, M., 2009. Com-

parative sclerochronology of modern

and mid-Pliocene (c. 3.5 Ma) Aequipec-

ten opercularis (Mollusca, Bivalvia): an

insight into past and future climate

change in the north-east Atlantic region.

Palaeogeogr. Palaeoclimatol. Palaeo-

ecol., 284, 164–179.

Kendrick, M.A., Burgess, R., Pattrick,

R.A.D. and Turner, G., 2002. Hydro-

thermal Fluid Origins in a Fluorite-Rich

Mississippi Valley-Type District:

combined Noble Gas (He, Ar, Kr) and

Halogen (Cl, Br, I) analysis of fluid

Inclusions from the South Pennine Ore

Field, United Kingdom. Econ. Geol., 97,

435–451.

Korte, C., Kozur, H.W., Bruckschen, P.

and Veizer, J., 2003. Strontium isotope

evolution of Late Permian and Triassic

seawater. Geoch. Cosmoch. Acta, 67, 47–

62.

Lohmann, K.C., 1988. Geochemical

patterns of meteoric diagenetic systems

and their application to studies of

paleokarst. In: Paleokarst (P. James

and P.W. Choquette, eds), pp. 58–80.

Springer-Verlag, New York.

Lomb, N.R., 1976. Least-squares

frequency analysis of unequally

spaced data. Astrophys. Space Sci., 39,

447–462.

Mii, H.S. and Grossman, E.L., 1994. Late

Pennsylvanian seasonality reflected in

the 18O and elemental composition of a

brachiopod shell. Geology, 22, 661–664.

Mii, H.S., Grossman, E.L., Yancey, T.E.,

Chuvashov, B. and Egorov, A., 2001.

Isotopic records of brachiopod shells

from the Russian Platform – evidence

for the onset of Mid-Carboniferous

glaciation. Chem. Geol., 175, 133–147.

Muehlenbachs, K. and Clayton, R.N.,

1976. Oxygen isotope composition of

the oceanic crust and its bearing on

seawater. J. Geophys. Res. Lett., 81,

4365–4369.

Pattison, J., 1981. The stratigraphical

distribution of gigantoproductoid

brachiopods in the Visean and

Namurian rocks of some areas in

northern England. Inst. Geol. Sci.

Report, 81 ⁄9, 30.

Popp, B.N., 1986. The Record of Carbon,

Oxygen, Sulfur, and Strontium Isotopes

and Trace Elements in Late Paleozoic

Brachiopods [Ph.D. Thesis]. University

of Illinois, Urbana, Illinois.

Popp, B.N., Anderson, T.F. and Sandberg,

P.A., 1986. Brachiopods as indicators of

original isotopic compositions in some

Paleozoic limestones. Geol. Soc. Am.

Bull., 97, 1262–1269.

Rasser, M.W. and Fenninger, A., 2002.

Paleoenvironmental and diagenetic

implications of d18O and d13C isotope

ratios from the Upper Jurassic Plassen

limestone (Northern Calcareous Alps,

Austria). Geobios, 35, 41–49.

Samtleben, C., Munnecke, A., Bickert, T.

and Patzold, J., 2001. Shell succession,

assemblage and species dependent effects

on C ⁄O-isotopic composition of

brachiopods - examples from the

Silurian of Gotland. Chem. Geol., 175,

61–107.

Heterogeneity, cyclicity and diagenesis 1• L. Angiolini et al. Terra Nova, Vol 00, No. 0, 1–11

.............................................................................................................................................................

10 � 2011 Blackwell Publishing Ltd

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

Scargle, J.D., 1989. Studies in astronomical

time series analysis III. Fourier

transform, autocorrelation functions,

and cross correlation functions of

unevenly spaced data. Astrophys. J., 343,

874–887.

Schone, B.R., Fiebig, J., Pfeiffer, M., Gless,

R., Hickson, J., Johnson, A.L.A.,

Dreyer, W. and Oschmann, W., 2005.

Climate record from a bivalve

Methuselah (Arctica islandica, Mollusca;

Iceland). Palaeogeogr. Palaeoclimatol.

Palaeoecol., 228, 130–148.

Schulz, M. and Stattegger, K., 1997.

SPECTRUM: spectrum analysis of

unevenly spaced paleoclimatic time

series. Comput. Geosci., 23, 929–945.

Scotese, C.R. and McKerrow, W.S., 1990.

Revised world maps and introduction.

In: Palaeozoic Palaeogeography and

Biogeography (W.S. McKerrow and

C.R. Scotese, eds). Geological Society

[London] Memoir, 12, 1–21.

Sharp, Z., 2007. Principles of Stable Isotope

Geochemistry. Pearson Education Inc,

??????.6

Taddei Ruggiero, E., 2001. Brachiopods of

the Isca submarine cave: observations

during ten years. In: Brachiopods Past

and Present (C.H.C. Brunton, L.R.M.

Cocks and S.L. Long, eds). The Sys-

tematics Association Special Volume

Series, 63, 261–267.

Tucker, M.E., 1990. Chapter 7 Diagenetic

Processes, products and environments.

In: Carbonate Sedimentology (M.E.

Tucker and V.P. Wright, eds), pp. ?????–

?????. Blackwell Scientific Publications,

Oxford.7

Tucker, M.E., Gallagher, J. and Leng,

M.J., 2009. Are beds in shelf carbonates

millennial-scale cycles? An example from

the mid-Carboniferous of northern

England. Sed. Geol., 214, 19–34.

Valencio, S.A., Ramos, A.M., Cagnoni,

M.C., Panarello, H.O., Cabaleri, N.G.

and Armella, C., 2003. Isotope signal of

the Middle Jurassic carbonate ramp of

Calabozo Formation, at arroyo El

Plomo, Mendoza, Argentina. Short

Papers, IV South American Symposium

on Isotope Geology, Salvador, 409–412.

Van Geldern, R., Joachimski, M.M., Day,

J., Jansen, U., Alvarez, F., Yolkin, E.A.

and Ma, X.P., 2006. Carbon, oxygen

and strontium isotope records of

Devonian brachiopod shell calcite.

Palaeogeogr. Palaeoclimatol.

Palaeoecol., 240, 47–67.

Veizer, J., Ala, D., Azmy, K., Bruckschen,

P., Buhl, D., Bruhn, F., Carden, G.A.F.,

Diener, A., Ebneth, S., Godderis, Y.,

Jasper, T., Korte, C., Pawellek, F.,

Podlaha, O.G. and Strass, H., 1999.87Sr ⁄ 86Sr, d18O and d13C evolution of

Phanerozoic seawater. Chem. Geol., 161,

59–88.

Williams, A., Brunton, H., Carlson, S.J.

et al. 2007. Treatise on Invertebrate

Palaeontology (Part H, Brachiopoda

revised). Vol. 6: Supplement. Geological

Society of America, Boulder, and

University of Kansas Press, Lawrence,

2321–3226. 8

Wright, V.P., 1990. Equatorial aridity and

climatic oscillations during the Early

Carboniferous, southern Britain. J. Geol.

Soc., 147, 359–363.

Wu, Z., Huang, N.E., Long, S.R. and

Peng, C.K., 2007. On the trend,

detrending, and variability of

nonlinear and nonstationary time

series. Proc. Nat. Acad. Sci., 104, 14889–

14894.

Received 15 April 2011; revised version

accepted 24 September 2011

Terra Nova, Vol 00, No. 0, 1–11 L. Angiolini et al. • Heterogeneity, cyclicity and diagenesis 1

.............................................................................................................................................................

� 2011 Blackwell Publishing Ltd 11

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

Author Query Form

Journal: TER

Article: 1032

Dear Author,

During the copy-editing of your paper, the following queries arose. Please respond to these by marking up

your proofs with the necessary changes/additions. Please write your answers on the query sheet if there is

insufficient space on the page proofs. Please write clearly and follow the conventions shown on the attached

corrections sheet. If returning the proof by fax do not write too close to the paper’s edge. Please remember

that illegible mark-ups may delay publication.

Many thanks for your assistance.

Query

reference

Query Remarks

1 AUTHOR: A running head short title was not supplied; please check if this

one is suitable and, if not, please supply a short title of up to 50 characters

that can be used instead.

2 AUTHOR: Please check that authors and their affiliations are correct.

3 AUTHOR: Please provide a current full postal address (including post ⁄zip

code) for the corresponding author

4 AUTHOR: Please check the �P << 0.01� has been changed to �P < 0.01�,

is this correct.

5 AUTHOR: As per Journal style journal titles are abbreviated, so please

check and provide abbreviated journal titles for some references.

6 AUTHOR: Please provide the city location of publisher for reference Sharp

(2007).

7 AUTHOR: Please provide the page range for reference Tucker (1990).

8 AUTHOR: Journal style is to include all author names for each reference in

the reference list. Please replace all appearances of �et al.� in your reference

list with the complete author lists.

USING e-ANNOTATION TOOLS FOR ELECTRONIC PROOF CORRECTION

Required software to e-Annotate PDFs: Adobe Acrobat Professional or Adobe Reader (version 8.0 or

above). (Note that this document uses screenshots from Adobe Reader X)

The latest version of Acrobat Reader can be downloaded for free at: http://get.adobe.com/reader/

Once you have Acrobat Reader open on your computer, click on the Comment tab at the right of the toolbar:

1. Replace (Ins) Tool Î for replacing text.

Strikes a line through text and opens up a text

box where replacement text can be entered.

How to use it

‚ Highlight a word or sentence.

‚ Click on the Replace (Ins) icon in the Annotations

section.

‚ Type the replacement text into the blue box that

appears.

This will open up a panel down the right side of the document. The majority of

tools you will use for annotating your proof will be in the Annotations section,

rkevwtgf"qrrqukvg0"YgÓxg"rkemgf"qwv"uqog"qh"vjgug"vqqnu"dgnqy<

2. Strikethrough (Del) Tool Î for deleting text.

Strikes a red line through text that is to be

deleted.

How to use it

‚ Highlight a word or sentence.

‚ Click on the Strikethrough (Del) icon in the

Annotations section.

3. Add note to text Tool Î for highlighting a section

to be changed to bold or italic.

Highlights text in yellow and opens up a text

box where comments can be entered.

How to use it

‚ Highlight the relevant section of text.

‚ Click on the Add note to text icon in the

Annotations section.

‚ Type instruction on what should be changed

regarding the text into the yellow box that

appears.

4. Add sticky note Tool Î for making notes at

specific points in the text.

Marks a point in the proof where a comment

needs to be highlighted.

How to use it

‚ Click on the Add sticky note icon in the

Annotations section.

‚ Click at the point in the proof where the comment

should be inserted.

‚ Type the comment into the yellow box that

appears.

USING e-ANNOTATION TOOLS FOR ELECTRONIC PROOF CORRECTION

For further information on how to annotate proofs, click on the Help menu to reveal a list of further options:

5. Attach File Tool Î for inserting large amounts of

text or replacement figures.

Inserts an icon linking to the attached file in the

appropriate pace in the text.

How to use it

‚ Click on the Attach File icon in the Annotations

section.

‚ Enkem"qp"vjg"rtqqh"vq"yjgtg"{qwÓf"nkmg"vjg"cvvcejgf"file to be linked.

‚ Select the file to be attached from your computer

or network.

‚ Select the colour and type of icon that will appear

in the proof. Click OK.

6. Add stamp Tool Î for approving a proof if no

corrections are required.

Inserts a selected stamp onto an appropriate

place in the proof.

How to use it

‚ Click on the Add stamp icon in the Annotations

section.

‚ Select the stamp you want to use. (The Approved

stamp is usually available directly in the menu that

appears).

‚ Enkem"qp"vjg"rtqqh"yjgtg"{qwÓf"nkmg"vjg"uvcor"vq"appear. (Where a proof is to be approved as it is,

this would normally be on the first page).

7. Drawing Markups Tools Î for drawing shapes, lines and freeform

annotations on proofs and commenting on these marks.

Allows shapes, lines and freeform annotations to be drawn on proofs and for

comment to be made on these marks..

How to use it

‚ Click on one of the shapes in the Drawing

Markups section.

‚ Click on the proof at the relevant point and

draw the selected shape with the cursor.

‚ To add a comment to the drawn shape,

move the cursor over the shape until an

arrowhead appears.

‚ Double click on the shape and type any

text in the red box that appears.