龙门山地震对川西天然气聚散的影响

“5.12”汶川大地震瞬间在龙门山内部形成了长达300 km 的地层岩石破裂错断，随后又发生余震4万多次，这必然改变其内部的压力疏导系统。地震对川西油气聚散有何影响是大家关心的问题。通过对地震特征、地震破裂与地下流体运移关系的分析，认为龙门山地震对川西地区油气运移聚散有着控制性的影响作用，并提出了一个龙门山地震控制川西油气运移聚散的概念模型。依据该模型分析认为，地震将导致龙门山推覆体地层中油气的散失和川西坳陷天然气的爆发式深生浅储成藏。该模型能较好地解释现今川西天然气藏的一些特点。

Effects of Longmenshan earthquake on migration and accumulation of natural gas in west Sichuan basin

This massive earthquake, which occurred in the Wenchuan town on May 12, 2008, tore open at an instant with a 300 km long broken zone of rocks in the internal information of the Longmen mountain, not even to mention those aftershocks for more than 37, 800 times, and thus inevitably changed the formation pressure drainage system. It is a concern for all what effects this earthquake has on the migration and accumulation of natural gas in west Sichuan basin. Therefore, through analysis on the relationship between the migration of underground fluids and the earthquake characteristics and ruptures, this study concludes that the Longmen earthquake performs control functions in the migration and accumulation of natural gas in west Sichuan basin, on which a conceptual model is proposed here. Based on this model, this study put forward that due to this earthquake oil and gas in those nappe formations will scatter and natural gas in west Sichuan depression will outbreak to generate in deep and accumulate in shallow reservoirs. This model can well interpret the features of natural gas reservoiring in west Sichuan basin, hopefully providing references for further oil and gas exploration there.