CAJ | 학술논문

鄂尔多斯盆地东北部上古生界发育多套含煤碎屑岩系,为上古生界气藏主要烃源岩.结合煤系气概念及其内涵,将上古生界天然气藏以下石盒子组区域分布的"桃花泥岩"为界划分为下部(C2b-P2x)煤系气藏以及上部(P2sh-P3q)非煤系气藏,并在沉降史模拟与构造热年代学分析的基础上,结合上古生界气藏压力分布特征,探讨了其成藏机制,认为上古生界天然气成藏可划分为4个阶段,其中煤系气成藏主要集中于145~115 Ma的加载增压原生成藏阶段以及115~65 Ma的压力调整再平衡成藏阶段;早白垩世末期以来南北生烃能力差异、煤系气横向运移的生气增压能量亏损、煤系气作为非煤系气源以及后期天然气逸散共同造成了煤系气藏纵向和横向上的压力分异;上古生界煤系气勘查应主要集中于研究区南部的米脂地区.
악이다사분지동북부상고생계발육다투함매쇄설암계,위상고생계기장주요경원암.결합매계기개념급기내함,장상고생계천연기장이하석합자조구역분포적"도화니암"위계화분위하부(C2b-P2x)매계기장이급상부(P2sh-P3q)비매계기장,병재침강사모의여구조열년대학분석적기출상,결합상고생계기장압력분포특정,탐토료기성장궤제,인위상고생계천연기성장가화분위4개계단,기중매계기성장주요집중우145~115 Ma적가재증압원생성장계단이급115~65 Ma적압력조정재평형성장계단;조백성세말기이래남북생경능력차이、매계기횡향운이적생기증압능량우손、매계기작위비매계기원이급후기천연기일산공동조성료매계기장종향화횡향상적압력분이;상고생계매계기감사응주요집중우연구구남부적미지지구.
In the northeastern Ordos Basin has developed multiple sets of upper Paleozoic coal-bearing clastic rock series thus the main gas reservoir source rock. Combined with coal measures gas concept and its conotation, divided the upper Paleozoic natural gas reservoir into lower part (C2b~P2x) coal measures gas reservoir and upper part (P2sh~P3q) non coal measures gas reservoir, taking the regionally distributed Taohua mudstone in Xiashihezi Formation as the boundary. Based on subsidence history simulation and tectonic thermal chronological analysis, combined with upper Paleozoic gas reservoir pressure distribution features, discussed its reservoiring mechanism. It is considered that the upper Paleozoic natural gas reservoring can be divided into 4 stages, in which, coal measures gas reservoring mainly concentrated in loading pressurized primary reservoiring stage (145~115 Ma) and pressure adjusting rebalanced reservoring stage (115~65 Ma). Since the end of early Cretaceous, hydrocarbon generation potential is different between south and north, coal measures gas lateral migration gas generation presurizing energy loss, coal measures gas played as non coal measures gas source and succeeding natural gas dissipation togather made vertical and lateral pressure differentiation. The prospecting of upper Pl-aeozoic coal measures gas should be mainly concentrated in Mizhi district in the southern study area.