The Research On The Organic Carbon And Elemental Geochemistry Of Coal-bearing Sequences In Lower Permian,Huainan Coalfield

The elemental geochemistry, the abudnaces and types of of organic matters in coal-bearing sequences of the Early Permian Taiyuan Formation and the Early Permian Shanxi Formation, Huainan Coalfield, and their relations with depositional environment, burial history and thermal evolution of coal basin are rarely reported. A deep understanding of these subjects is of great worth to evaluate the coal-bearing resources, explore coal-derived hydrocarbon energy and guide non-traditional oil-gas exploration.On basis of theories of geology, geochemistry, mineralogy and petrology, this dissertation uses state-of-art instruments including ICP-AES, ICP-MS, XRD, XRF, optical microscopy, SEM to study the sedimentary rock samples (mudstone, coal and limestone) taken from the representative boreholes. The results are listed below:1) these parameters of petrology, minerology and elemental geochemistry indicate that the Shanxi Foramtion is specified priority to with underwater delta sedimentary facies; Taiyuan Foramtion is given priority to with shelf facies, demostrating a difference in the depositional envrionments between Shanxi Formation and Taiyuan Formation; 2) The comparison in the abundances of major elements, trace elements and rare earth elements between coal-bearing sequences studied in Shanxi-Taiyuan formations and the rocks in North China platform of similar lithology reveals that the former inherit the elements from the latter; 3) The storage and difference of burial organic carbon were studied in coals from Taiyuan and Shanxi Formation in relation to abundances and types of organic matters and evolution history of local depositional environment, and burial history and thermal evolution history of coal basin; 4) The geochemical factors and oragnaic affinities of elements in coal-bearing seams of Shanxi-Taiyuan Formation reveal the relationships between the abundaces of organic matters and paleo-sedimentary system (paleotemperature, paleosalinity and paleoclimate), and propose two genetic patterns of organic matter in the coal-bearing sequences of Early Permian.