Lecture 1 Introduction presentation

Dr. Abdelaziz El- Shinawy

Introduction :

1. Geological Terminology.

Syngenetic deposits, Lateritic deposits, Ore and gongue,

Disseminated and Massive ores, Cut off grade, Placer and

alluvial deposits and Bedded deposits.

2. Mining Terminology

Large deep ore bodies, Large shallow ore bodies and coal

mining.


The simplest form of rock strata is that in which each layer ofrock is superimposed on another , these are conformable beds.

Movements of the earths crust, subsequent weathering and rockdisplacement provide for mineral formation and relocationinto the site where it will be found.

The original layers of rock were formed by sedimentary orchemical processes with material from higher land massesbeing redeposit in lower areas.


Geological terminology.

The beds could then be distorted into folds to produce synclines or

anticlines, where the folding is server the rock is frequently

heavily fractured particularly where it is under tension on the

crest of an anticlinal stratum or at the base of a synclinal

stratum.

The weakened zones provide apath for igneous intrusive rocks or

mineral rich solutions to permate the host rock and produce

orebodies.


Syngenetic deposits are those mineral deposits formed

contemporaneously with the parent rock and enclosed by it.

( they can be igneous and sedimentary).


Ore and Gongue

An ore body may contain both desirable metallic minerals and

unwanted nonmetallic minerals. The metallic minerals from the

ore and the unwanted minerals are known as gongue.

Disseminated and massive ores

Where the ore occurs in relatively pure form, for example as almost

100 percent lead sulphide (Galena) in even small amount, it is

said to be Massive.

If however the ore is spread thinly through a body of rock sothat individual specks of the ore are surrounded by a highpercentage of rock then this is a disseminated ore.


Cut-off Grade

A gradual transition of high grade to low grade ore is common, it is

not always easy to determine the physical limits of an orebody.


Placer and Alluvial Deposits

When the primary deposits are brought to the surface by geological

methods, and then mechanically eroded.

Bedded Deposits

Chemical and physical deposition of consolidated minerals can

produce bedded deposits which may extend over large areas,

these are minerals such as coal, iron ore, salt or potash deposits

and phosphates.


Mining Terminology

Large Deep Ore bodies

Are often known as massive, a vein type ore body will probably

contain bands of massive ore minerals.

Vein type ore bodies

A large ore body may in fact consist of clusters of smaller ore

bodies of a vein type and development may be on a regular

grid.


Shallow orebodies are worked as open pit mining operationswherever possible.

The scale of equipment is generally smaller in metalliferousorebodies than in shallow bedded deposits, because of theneed for brenching downwards.

Large Shallow Orebodies


Coal Mining

Usually a regular layer of rock stratum, which when it is coal is

called a seam, rather than with an irregular orebody.

Cosequantly the seam has a roof and a floor, Surface mining of

coal is called opencast mining.

The initial opening into a coal seam for opencast mining known

as a box cut.


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Lecture 1 Introduction presentation

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Transcript of Lecture 1 Introduction presentation