Depositional Environments of Coal and Coal-Bearing Strata
- R. A. Rahmani and
- R. M. Flores
Published Online: 28 APR 2009
Copyright © 1984 The International Association of Sedimentologists
Sedimentology of Coal and Coal-Bearing Sequences
How to Cite
McCabe, P. J. (1985) Depositional Environments of Coal and Coal-Bearing Strata, in Sedimentology of Coal and Coal-Bearing Sequences (eds R. A. Rahmani and R. M. Flores), Blackwell Publishing Ltd., Oxford, UK. doi: 10.1002/9781444303797.ch2
- Published Online: 28 APR 2009
- Published Print: 26 MAR 1985
Print ISBN: 9780632012862
Online ISBN: 9781444303797
- general coal depositional models;
- plant derived minerals;
- coal and peat erosion
Most published depositional models for coal-bearing strata suggest that coal originated as peat which formed in swamps on low-lying ground in deltas, alluvial plains and coastal areas. A review of the literature suggests that such models may have to be modified. Peats from modern swamps similar to those depicted in the models have a high percentage of inorganic material introduced by floods and storms. If preserved in the geologic record, such peats would be transformed to carbonaceous shales or, at best, high ash coals.
Some coals may have originated as peats in floating or raised swamps. Peats from these types of swamps have low ash contents even in areas close to active clastic deposition. The geometry of floating and raised swamps probably influences the style and packaging of associated clastic sediments. Other coals may have originated in swamps far removed from active clastic environments. In these coals there was presumably a significant hiatus in time between deposition of underlying sediments and the coal. An understanding of the environment of deposition of sediment overlying a coal seam can be as important as a knowledge of underlying sediments in predicting a coal's properties.
Integrated studies of clastic sedimentology, coal petrography and palaeontology are necessary for an understanding of the nature of ancient swamps. Such studies should lead to the development of facies models with greater predictive power for use in coal exploration and development.