试论复杂地质体的油气地震勘探

Seismic prospecting for oil and gas on the complex geological bodies

论述了我国油气勘探工作中反射地震的发展历程,指出地震勘探中信噪比与分辨率之间的矛盾,针对中国前新生代海相残留盆地具有埋藏深、演化历史长、经受地质作用多,以致地表和地下条件都很复杂的特点,提出了复杂地质体油气地震勘探的理念和方法途径.我国油气资源多存储于复杂地质体如生物礁、鲕滩、风化壳、古潜山等储集体之中.不能完全搬用陆相油气勘探的经验.应在活动论大地构造理论指导下,根据“区域约束局部,深层制约浅层”的勘探经验,探索测区的时空演化规律,设计复杂地质体的观测系统,采取高密度连续采集技术,获取反射地震资料,再进行高分辨率与高信噪比的处理,从而使地震采集、处理与解释一体化,减轻山地采集困难,获取深部成像资料,在新的高度上寻找在复杂地质体中的油气资源.使地震勘探能在中国油气二次创业中发挥重要作用.

In this paper, we discuss the development listory of refleection seismology for oil and gas prospecting in our country and point out the contradiction between signal-to-noise ratio and resolution power in seismic prospecting. We propose opinions and solution approaches for complex geologic bodies aiming at the complicated curface and subsurface conditions of Precenozoic marine-phase residual basins of China which are characteristic of deep buried depth, long evolution history, and many geologic actions. Hydrocarbon resources in our country aremostly stored in such complex geologic bodies such as biogenic reef, oolitic shoal, crust of weathering, and burial hill. Therefore, we cannot entirely follow the experience of continental-phase hydrocarbon prospecting, under the guidance of mobilism geotectonic theory and the prospecting experience of ＂Region constrains local, deep strata control shallow ones＂ we probe onto temporal and spatial evolution rules of surveyed areas, design observation system for complex geologic bodies, apply for highly dense and continuous acquisition technology, obtain reflected seismic data, and process data with high resolution and signal-to-noise ratio. Thereby, seismic data acquistion, processing, and interpretation can be integrated. The difficulties of seismic acquistion in mountainous ares can be reduced and deep imaging data can be obtained. Finally hyfrocarbon resources from complex geologic bodies can be explored in a new height; and thus seismic prospecting can play an important role in the second round of exploitation of oil and gas resources in China.