Shale

Shale

1. SHALE

2. fine-grained  sedimentary rock  that forms from the compaction of silt and clay-size mineral particles commonly called "mud". category of sedimentary rocks are known as “mudstones". it is fissile and laminated. "Laminated“-  rock is made up of many thin layers. "Fissile“  rock readily splits into thin pieces along the laminations. DEFINITION

3. Composition of Shale Composed mainly of clay-size mineral grains. Tiny grains are usually clay minerals such as illite , kaolinite and smectite other clay-size mineral particles such as   quaetz , chert and felddspar . Constituents include organic particles, carbonate minerals , iron oxide minerals , sulfide minerals and heavy mineral grains. Other constituents in the rock are determined by the shale's environment of deposition and the colour of the rock. 

4. starts from the compaction and consolidation of silt and clay grade materials. compacted mud still retains 10-15% of moisture termed as clays continued compaction results in further loss of moisture and orientation of clay and platy minerals takes place in parallel layers. if orientation does takes place, the deposits attain the property of fissility , called as “SHALE”. If gets further compacted without any fissility , it may be a mudstone or claystone and not a shale. FORMATION

5. CLASSIFICATION OF SHALE F.J.Pettijohn classification W.C.Krumbein and L.L.Sloss classification

6. F.J.Pettijohn classification Residual shales : formed from decay and decomposition of pre-existing rocks followed by compaction and consolidation Transported shales : deposits of clastic materials of finer dimensions transported over wide distances before final settlement in basins of deposition Hybrid shales : derived from both clastic and non clastic sources

7. W.C.KRUMBEIN AND L.L.SLOSS CLASSIFICATION QUARTZ SHALES : rich in free quartz content FELSPATHIC SHALES : felspars and clay minerals are predominate CHLORITIC SHALES: minerals of chlorite group and clay group makes the bulk of the shales MICACEOUS SHALES : rich in muscovite mica and other flaky and play minerals

8. QUARTZ SHALE MICACEOUS SHALE

9. STRUCTURES Fissility : tendency of rock to split into flat , shell like fragments parallel to bedding. partly primary and seconday in nature primary fissility results during the process of deposition . secondary fissility develops after the deposition. Lamination : laminations in very thin layers of thickness from 0.05mm to 1.00mm.

10. Black shales contain organic material that breaks down to form natural gas or oil. crushed and mixed with water to produce clays made into a variety of useful objects.  used for manufacture of bricks and tiles. place source of alumina,paraffin and oil . USES OF SHALE

11. BRECCIA

12. DEFINITION : mechanically formed sedimentary rock classed as rudite. Consists of angular fragments of heterogeneous composition embedded in a fine matrix of clayey material. FORMATION : Breccia forms where broken, angular fragments of rock or mineral debris accumulate.   After deposition bound together by a mineral cement or by a matrix of smaller particles that fills

13. DEBRIS BRECCIA

14. TYPES BASAL BRECCIA: formed by sea waters advancing over coastal regions covered with fragments of chert advancing waters supply fine mud , which spread over rock fragments , acts as binding material

15. FAULT BRECCIA called as crush breccia . made up of angular fragments. The fragments are produced by crushing effect of block movements subsequently get embedded in clay and other fine material

16. AGGLOMERATIC BRECCIA contains angular, sub-angular fragments derived from volcanic eruptions. also contains fused material cemented together with solid material broken and thrown out of the craters

17. These breccias are used as architectural stones for interior building veneers, tiles, window sills other decorative applications. USES

18. COAL

19. DEFINITION Coal defined as m etamorphosed sedimentary rocks of carbonaceous character The raw materials has supplied by plants of various groups The raw material passes through many biomechanical and biochemical process before it becomes coal in technical terms.

20. FORMATION BIOMECHANICAL PROCESS The transport of raw material through different natural agencies to places of deposition accumulation of material in huge formation its burial under clays other matter and compaction and consolidation under super imposed load BIOCHEMICAL TRANSFORMATION Organic matter accumulates undergoes reaction with aerobic and anaerobic bacteria and called as carbonification The degree of carbonification depends to a great extent on the time, type of the environment

21. TYPES OF COAL Coals are generally classified on the basis of their carbon content. V arieties of coal Peat Lignite Bituminous Anthracite PEAT lowest grade coal Rich in volatile matter Has very low calorific value

22. PEAT

23. LIGNITE Brown coal Poorest grade of coal Calorific value ranging between 6300-8300B.th.U Specific gravity-1.5 Hardness -2.5 on moh`s scale It shows some traces of original vegetable matter

24. BITUMINOUS COAL forms a broad group of coals having essential properties Carbon content-69-78% Calorific value-9500-14000 B.th.U Enough volatile matter makes them quite soft on heating and they start agglomerating

25. ANTHRACITE Coal of highest grade Carbon content-92-98% Highest calorific value and burns almost without any smoke Volatile matter is negligible

26. OCCURRENCE Coals of different variety are found to occur almost in all countries of the world Coal forms all-purpose fuels