博格达南、北缘成盆过程演化及其对油气形成影响

以博格达地史演化为主线，探讨博格达构造域成盆—成烃—成藏的演化过程。研究认为，博格达构造域时空演化具有明显的分期性、分段性，其演化历程大体经历三个阶段:①泥盆纪—早二叠世西博格达为陆内裂谷阶段，东博格达经历泥盆纪—石炭纪裂谷演化阶段后于石炭纪末期裂谷回返形成褶隆；②晚二叠世—侏罗纪西博格达为裂谷后坳陷阶段，东博格达褶隆进一步隆升形成界山雏形，南缘进入弱压陷—挠曲沉降阶段；③侏罗纪末期—第四纪西博格达裂谷开始回返隆升成山，北缘形成阜康前陆，东博格达界山雏形再度隆起，南缘形成前陆。成盆—成烃—成藏演化史表明，西博格达经历裂谷后期坳陷阶段湖相烃源岩发育（P2），后期（T-J）深埋，晚期（J末-Q）裂谷回返隆升造山致使油气破坏阶段，造山前期远源运聚成藏较为有利；东博格达南缘经历多期压陷-挠曲沉降，发育湖-沼相多套泥质、煤系烃源岩（P2-J2）互层，前侏罗纪构造格局控制上二叠统油气系统远源运聚成藏，侏罗纪末期以来造山运动所形成的构造格局控制中、下侏罗统油气系统源内（或近源）垂向运聚成藏。

Basin-formation Evolution and Its Effect on Petroleum Formation in the Southern and Northern Margins of Bogda

Based on the geological history evolution of Bogda, in this paper the process of basin formation, hydrocarbon generation and petroleum accumulation of Bogda region are discussed. According to the obvious multi phases and segmentations in spatial and temporal evolution, it can be divided into 3 phases: ① from late Devonian to early Permian west Bogda was in intracontinental rifting stage while east Bogda was folded into uplift by inversion in late Carboniferous after experiencing the rifting from Devonian to Carboniferous; Be continued on page 98)②from late Permian to Jurassic west Bogda was in post rifting stage, east Bogda showed the rudiment of mountain with further uplifting, southern margin was in weak pressure flexure subsidence stage；③from late Jurassic to Quaternary west Bogda rifting was folded into the mountains by inversion, northern and southern margins were evolved into forelands, east Bogda experienced further uplifting. The evolution of basin formation, hydrocarbon generation and petroleum accumulation of Bogda region suggests: lacustrine source rock developed in west Bogda during post rifting (P2), which experienced deep burial history(T J), later uplifting from rifting by inversion destroyed former reservoir, far sourced petroleum accumulating is favorable before incipient uplifting; southern margin of east Bogda experienced multi phases' pressure flexural subsidences, multi interbedded mudstone and coal hydrocarbon of lake swamp facies developed(P2 J2), former Jurrasic rise controls far sourced oil and gas accumulation of upper Permian petroleum system, the fault related folds traps by orogeny since late Jurassic control vertical oil and gas accumulation in Jurassic source rock.