A study of depositional material and environment of specific organic rocks
Speaker: Shun-Wen Yu
Abstract
Although the mechanism of coalification process had been well discussed in literatures, detailed studies of special organic rocks are still lacking. In this study, samples from China include torbanite from Fushun and Zibo, as well as oil shale from Maoming were studied and compared with humic coal from Lifung, Taiwan. The study methods include petrographic analysis, elemental analysis, Rock-Eval pyrolysis, and GC/biomarker analysis. The experimental results are listed ： (1)From petrographic analysis, the major maceral of Lifung is vitrinite. Zibo and Fushun have relatively higher liptinite content than Lifung, which implied different organic source or depositional mechanism. (2)The coal of Zibo might be formed in shallower water than others, similarly as suggested by past literatures. (3)Although the coal of Lifung has less liptinite than Zibo and Fushun, it has relatively the least liptodetrinite. The coal of Lifung is thus believed to be lessly affected by depositional activities than others during the process of coalification. (4)Vitrinite reflectance histograms of Zibo and Maoming implied a possible reworked source material. The results of this study will be further combined with regional geology information of each sample, so as to evaluate the depositional mechanism of previously less-studied organic rocks.
Reference
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