塔中地区深部流体活动及其对油气成藏的热作用

利用塔中地区钻井岩心、分析化验、地震等资料，系统地分析了深部流体活动机制及其对油气成藏的热作用。通过奥陶系岩石热液矿化蚀变、古地温异常及CO₂无机成因气与储层包裹体测温等研究后认为：深部流体通过地震、火山或其它各种通道，如断裂、不整合面等向浅部运移；深部流体提高生烃量及生烃速率，而且降低烃源岩中残余有机质含量，影响有效烃源岩评价；深部流体对油气储层的影响，既有热液方解石充填的破坏性,又有热液溶蚀、热液次生矿物带的建设性；深部流体在向上运移的过程中形成异常高压, 为油气二次运移提供动力。深部流体对天然气形成的热作用、储层改造与成藏动力学方面，不仅在能量上，而且在物质上都对油气藏的形成和演化起到重要影响，并使塔中地区奥陶系油气成因更加复杂化。

Deep Fluid Activity in Central Tarim Basin and Its Heating Effects on Hydrocarbon Generation and Accumulation

Based on data from drilling core, analysis assay and seismic data of the Central Tarim area, the authors deal systematically with the activities and mechanism of the deep fluid as well as its thermal effect on hydrocarbon accumulation. Based on the study for hydrothermal mineralization and alteration of Ordovician rock, paleo thermal anomaly, inorganic CO₂ gas reservoir, inclusion temperature measurement and so on, the following conclusions are arrived: throught seismic, volcano or other variable channels such as fault, unconformity and so on, the deep fluid migrated upwards. Such fluid could improve not only the hydrocarbon-generation quantity and rate, but also lower the residual organic content in source rock and affects the hydrocarbon source rock evaluation. Deep fluid both has the destructive role of hydrothermal calcite filling and the constructive role of hydrothermal corrosion and hydrothermal secondary minerals for the gas reservoir. During the process of upward migration, abnormal high pressure caused by the deep hot fluid provides power for the secondary oil migration. For the thermal effect of gas formation, reservoir reconstruction and hydrocarbon accumulation dynamics，the deep fluid both has more important influence on the formation and evolution of the old reservoir in light of energy and material aspects，and make the origin of the hydrocarbon more complicated in Ordovician strata of the Central Tarim area.