Establishment of Source Beds

The source bed concept of coal genesis is the outcome of an attempt over the past century or more to find answers to some of the outstanding problems of coal genesis—answers that would be of practical assistance in the difficult task of finding new coal seams. 

The approach is to search for some phenomenon of coal habitat conunon to several major coal seams. One such phenomenon emerged from a study of many mining operations, namely, the correlation between stratigraphy and coal seams where the seams may be restricted to one particular sedimentary horizon. 

The source bed concept postulates that all coal seams are derived from plant material that was deposited syngeneticaUy at one particular horizon of the sedimentary basin constituting the field, and that changes to the plant material changed (evolved) to coal in varying degrees under the influence of rise in temperature and pressure of the rock environment. 

The accumulated, compacted, and altered plants form the sedimentary rock that we know as coal. However, moving beyond the source bed concept, there are two theories that have been proposed to explain the formation of coal. 

The first theory suggests that coal strata accumulated from plants which had been rapidly transported and deposited under flood conditions. This second theory which claims transportation of vegetable debris is called the allochthonous theory. 

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