Coal-bearing strata and methods of its study
Abstract
At present, it can already be considered sufficiently clear that coal-bearing strata represent unique geological polyfacial formations, appearing in the history of the earth under certain conditions. In a number of characteristic features, they differ sharply from other equally typical formations, for example, flysch, molasse, salt-bearing, etc. However, the conditions of formation, as well as the very nature of coal-bearing deposits, do not remain constant for all geological periods, but, on the contrary, reveal changes and development. This development for large segments of geological history reveals its progressive nature, although it experiences periodic fluctuations and deviations, reflecting in this sense the general course of development of the earth. The present work sets as its task, by analyzing a wide range of material, to reveal the features of coal-bearing sediments, as a certain type of deposits, and to illuminate the patterns of their accumulation; and on the basis of the latter, to outline specific methods of study, arising precisely from their characteristic features, not inherent in many other complexes of deposits.