塔里木盆地孔雀河古斜坡成藏条件新认识

尉犁1井是塔里木盆地东北缘第一口钻揭震旦系的井,它的钻探分析对了解孔雀河古斜坡成藏条件、确定该区下一步有利勘探区具有重要的意义。对尉犁1井中、下寒武统的岩心观察、电子探针岩样成分分析、热解分析及单井的盆模综合研究,确定塔里木盆地东北缘孔雀河古斜坡寒武系—下奥陶统烃源岩经历一次深埋热演化后,其有机质演化产物已接近石墨,不具备二次生烃的能力;寒武系—下奥陶统中早期发育的裂缝和溶蚀孔洞是古油藏的主要储集空间。研究尉犁断鼻成藏史认为,该区的成藏具有早期成藏、自生自储、一期破坏、二期调整的特点。最后根据尉犁1井失利原因讨论了孔雀河地区有利的勘探圈闭样式:原生未被断层改造的下古生界的古背斜为有利油气圈闭;其次是在古背斜上继承发育的断背斜圈闭;最后为岩性圈闭和不整合面-岩性圈闭;而古断鼻构造圈闭不是有利的油气圈闭。 

THE NEW RECOGNITION OF RESERVOIR-FORMING CONDITION OF KONGQUEHE PALAEOSLOPE IN THE TARIM BASIN

The Well Yuli 1 is the first well which drills through Sinian System on the northeast margin of the Tarim Basin.This is on the significance to know reservoir-forming condition and to determine the favourable exploration targets of the Kongquehe palaeoslope area by drilling consequent analysis of the Well Yuli 1.The results of observation of core,the analysis of the rock sample component by electron microprobe's method,the pyrogenation analysis and the basin modeling comprehensive research show that the thermal evolution of organic matter of Cambrian-Lower Ordovician source rocks in the Kongquehe palaeoslope approach coal and the Cambrian-Lower Ordovician source rocks are not the capability of secondary hydrocarbon generation after its experienced one buried depth in its burial history.The main reservoir space of Cambrian-Lower Ordovician paleo-reservoir is crack and corrosion hole which were formed early period.Reservoir-forming characteristic in the Kongquehe is early reservoir-forming,self-generating and self-storing,one stage destroying,tow stage adjusting.By discussing the favourable exploration trap in the Kongquehe area,we get the following conclution: transverse nose-shaped trap is not favourable trap; the Lower Palaeozoic paleo-anticline is more better exploration trap and breaking-anticline;lithologic trap and unconformit trap is good exploration trap.