塔里木东北部英南2气藏天然气运移和聚集

GAS MIGRATION AND ACCUMULATION OF THE YINGNAN 2 GAS POOL IN NORTHEASTERN TARIM, XINJIANG

基于大量的地质和地球化学证据 ,本文详细论述了塔里木盆地塔东北地区英吉苏凹陷英南 2气藏的天然气运移和聚集。研究指出 :英南 2气藏天然气主要来源于寒武系烃源岩 ,为早期聚集的寒武系来源油的裂解气。该气藏的成藏期主要为燕山末期 ,天然气的运移通道主要为沟通寒武系古油藏与上覆侏罗系圈闭的断裂。英南 2气藏的聚集过程导致了其与邻近构造油气聚集的差异 ,也导致了其天然气地球化学特征上的差异。

Based on a series of geological and geochemical evidence, the paper expounded, in detail, the natural gas migration and accumulation of the Yinnan 2 gas pool in the Yingjisu Sag, northeastern area of the Tarim Basin. It was represented that the natural gas in the Yingnan 2 gas pool came mainly from the Cambrian source rocks, which was a cracking gas from oil in the Cambrian accumulated in earlier period. The gas pool-forming period might be mainly in the terminal of Yanshanian orogeny, with a gas migration channel being fractures which connected the ancient oil pool in the Cambrian and the overlying Jurassic traps. It was the accumulation process of the Yingnan 2 gas pool that resulted in the defference from the oil-gas accumulations in the neighboring structures, also, the features of natural gas geochemistry of the Yingnan 2 gas pool were different from that of the neighboring gas pools. Based on mentioned-above, the exploration direction in northeast Tarim in the near future was discussed.