白家海-五彩湾地区天然气成藏特征

准噶尔盆地东部白家海——王彩湾地区处于多个生油凹陷交汇区，发育石炭系海陆交互相、二叠系平地泉组、三叠系小泉沟群湖相泥岩和侏罗系煤系地层等多套烃源岩。油气来自于多个生烃凹陷的多套烃源岩，具有先油后气，多期充注的特征。在石炭系塔木岗组、巴塔玛依内山组、三叠系烧房沟组、侏罗系八道湾组、三工河组和西山窑组均获得工业气流。东道海子北凹陷、昌吉凹陷深部二叠系平地泉组烃源岩已达到成熟-过成熟阶段，对白家海凸起的天然气贡献较大；五彩湾凹陷石炭系滴水泉组、巴塔玛依内山组烃源岩已达到成熟阶段。白家海凸起天然气主要分布在生气中心附近，近距离运移聚集成藏，五彩湾凹陷以石炭系自生自储的天然气藏为主。

Gas Accumulation Characteristics in Baijiahai-Wucaiwan Area

Baijiahai-Wucaiwan area is in line intersection of multiple source sags i n eastern Junggar basin,with multiple hydrocarbon source rocks composed of Carb oniferous continental-oceanic interaction deposits,Permian Pingdiquan formatio n and Triassic Xiaoquangou group lake mudstone,and Jurassic coal measure strata .It is characterized by multi-filled oil in the early time and gas in the late time.Commercial gas flow is output from Carboniferous Tamugang formation and Batamayineishan formation,Triassic Shaofanggou formation,and Jurassic Badaowan ,San-gonghe and Xishanyao formations.The source rocks in deep of north sag of Dongdaohaizi and Changji sag have been in matured-over matured stage,which co ntribute much to gas reservoir in Baijiahai salient;while the source rocks in C arboniferous Dishuiquan and Batamayineishan for-mations in Wucaiwan sag have re ached the matured stage.Natural gas in Baijiahai salient is mostly distributed near the gas-generated center and by way of close distance migration and accum ulation,form gas reservoir(s).Wucaiwan sag is dominated by gas reservoirs wi th both source and reservoir in Carboniferous system.