Maceral and geochemical characteristics of coal seam 1 and oil shale 1 in fault-controlled Huangxian basin, China

Seven samples of coal seam 1 and oil shale 1 from the fault-controlled Hang xiang Basin have been analysed by coal petrographic and geochemical methods . High huminite ratios and high contents of sesquiterpenoids and diterpenoi ds indicate that coal seam 1 and oil shale 1 are predominantly composed of terrestrial higher plant material. Two ternary diagrams of "facies diagnost ic" macerals and biomarkers were used to interpret the depositional environ ments of organic matter in coal seam 1 and oil shale 1. In both diagrams co al seam 1 is plotted in the forest moor zone, but the top sample of coal se am 1 shows an influence of transgressed sea water. Oil shale 1 is plotted i n a transition zone from forest moor to open moor. This indicates an increa sed abundance of lower plants and algal derived organic matter in oil shale I relative to coal seam I. The boundary faults controlled the sedimentatio n in Huangxian basin. When the faults ceased to move, the peat of coal seam 1 was formed. When the faults became active again and the basin began to s ink, sea water flowed into the swamps at which time oil shale 1 was deposit ed. (C) 1998 Elsevier Science Ltd. All rights reserved.