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下古生界奥陶系Gloeocapsomorpha prisca(G.prisca)富集的Kukersite型烃源岩在全球范围内是一套重要的油气源岩,所以塔里木盆地中-上奥陶统主力烃源层中是否发育Kukersite型烃源岩在油气勘探中备受关注.研究通过中等成熟度灰泥丘相沉积源岩干酪根裂解-色谱-质谱分析,揭示了塔里木盆地奥陶纪地层中存在典型Kukersite型烃源岩,裂解产物表现为低含量>n-C19链烃,在n-C13～n-C17之间存在明显奇偶优势;以正构长链烷基取代异构体为主的烷基苯系列和烷基噻吩系列;以及特征性的5-正烷基-1,3-苯二酚及其同系物分布等.根据G.prisca繁育的地理环境特征,并结合目前已经揭示的塔里木盆地下古生界含油气系统原油特征和典型中-上奥陶统烃源岩干酪根裂解产物组成特征,提出塔里木盆地中-上奥陶统主力烃源层中大规模发育G.prisca富集的Kukersite型烃源岩的可能性较小,而主要发育以宏观底栖藻或浮游藻类为主的烃源岩.
Lower Paleozoic Kukersite type source rocks enriched in the Gloeocapsomorpha prisca (G.prisca) are an important source of hydrocarbon source rocks in the world, so whether the Middle-Upper Ordovician source rock in the Tarim Basin is The development of Kukersite type source rocks has attracted much attention in oil and gas exploration.By means of kerogen pyrolysis-chromatography-mass spectrometry analysis of middle maturity mound facies sedimentary source rocks, it reveals the existence of typical Kukersite type hydrocarbon source in Ordovician strata of Tarim Basin Rock and cracking products showed low content of n-C19 chain hydrocarbons, and there was a clear odd-even advantage between n-C13 and n-C17. Alkylbenzenes mainly consisted of n-C13 ~ n- Thiophene series and the characteristic 5-n-alkyl-1,3-benzenediol and its homologue distribution, etc. According to the characteristics of G.prisca breeding geography environment, combined with the presently revealed Lower Paleozoic The petroleum characteristics of the petroleum system and the kerogen pyrolysis product composition of the typical mid-upper Ordovician hydrocarbon source rocks are discussed. The Kuprising-type hydrocarbon source enriched by G.prisca enrichment in the middle-upper Ordovician source rock in the Tarim Basin Rock less likely, while the main development in macro Benthic algae or phytoplankton dominated source rock.