| Santanghu Basin,located in the northeast of Xinjiang Uighur Autonomous Region, bordering on Junggar basin to the west and Turpan-Hami Basin to the south,neighboring in Mongilia in northeast,the basin is generally NW-SE distributed.Santanghu Basin is a compound petroliferous basin with small areal extent,and it is formed by the superposition of various prototype basins from different age in tectonic evolution,which is in the south margin of Siberia Plate,south to Kazakhstan- Junggar Plate.The basin is located in the joint between the Kazakhstanian Plate and the Siberian Plate,situated between the Altai and Kelamaili structural belt,overlain the Paleozoic orogenic belt,and its tectonic position results in a complex tectonic evolutionary history for the basin.On the basis of the study in sedimentary thickness of the Carboniferous clastic rock,we mainly do some research on the Batamayineishan(C2b),the Haerjiawu(C2h) and the Kalagang Formation(C2k) of the Upper Carboniferous from the Santanghu area.It is inferred that the Haerjiawu Formation(C2h) is the primary sedimentary period for the Upper Carboniferous mudstone,and it is the primary source rocks as well.Among all of them,the mudstone of the Haerjiawu mostly is well or perfect source rocks,and the mudstone of Kalagang is generally kerogen typeâ…¡2-â…¢,dominated by typeâ…¡2,contained a little kerogen typeâ… andâ…¡1.That of the Haerjiawu is mainly kerogen typeâ…¡2 orâ…¢,and that of the Batamayineishan is mainly kerogen typeâ…¢.The Upper Carboniferous source rocks in Santanghu are in the early or middle of maturity;A few samples reach the stage of hydrocarbon-humid gas generation as to thermal evolution degree.The thermal maturity of mudstone from Batamayineishan is higher than that of the Kalagang and Haerjiawu Formation.The mudstone samples from Santanghu section are mainly poor or general source rocks.Source rocks from the Jiangbasitao Formation are better than that of the Batamayineishan,and the Haerjiawu are the poorest in all of them.According to the geochemical characteristics of soluble organic matter of core samples from the Carboniferous source rocks in Santanghu basin,it is concluded that the Upper Carboniferous was deposited under fresh water environment,and characterized by different deep or shallow water.Based on the geochemical characteristics of soluble organic matter from surface samples,five sections included Yiwu,Zhifang,Daheishan and samples in the basin,it is inferred that the organic matter were formed under salt water reducing environment,organic matter was mainly from lower hydrobiont such as algae and bacteria, the soluble organic matter of core samples in the basin are generally typeâ…¡-â…¢,that is sapropel-humic or humic type,while section samples are mainly sapropel in type.As far as various biomarker parameters concerned,section samples of the Carboniferous were deposited under a reducing environment with salty deep water,organic matter was sapropel type(marine algae typeâ…¡-â… type),and which was mainly derived from hydrobiont such as algae,include a little bacteria and terrigenous matters;Organic matter was high mature in evolution as a whole.The tectonic-thermal event since Hercynian Movement was positive for the maturity of the Carboniferous source rocks,magmatic activity increased geothermal gradient,and promoted the Carboniferous source rocks in the area being mature quickly,all of which were made for the formation of hydrocarbon.Additionally,volcano-magmatic activities brought abundant mantle matters,and these matters played a significant role in promoting hydrocarbon generation and evolution.The geochemical characteristic of the source rock samples from the side of diabase in different distance revealed high maturity of this group of source rocks,and the maturity parameters of organic matters increased abnormally in the range of 1m-1.5m distance to the rock,which show that the bake range of intrusive body and its direct contact source rocks was quite small,range in 1.5m.
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