海域天然气水合物的地震研究进展

Advances in seismic researches on natural gas hydrate in ocean

海域天然气水合物的地震研究是在岩石物性分析成果的指导下,用地震技术进行真假BSR的识别和含水合物沉积层物性预测.海域天然气水合物地震研究的进展主要表现在:物性分析理论模型由简单模型发展到最大程度模拟实际情况的复杂模型;地震勘探方法已由常规的单道、多道地震发展到多频地震、高分辨率二维、三维地震和海底多分量地震;地震资料处理由常规处理发展到突出BSR特征的“三高”和叠前时间偏移处理;从利用速度、振幅结构研究识别天然气水合物发展到AVO、多属性判别、多弹性参数和多物性参数反演识别天然气水合物、预测其物性参数.这些新技术、新方法的应用,加快了海域天然气水合物调查进度,提高了天然气水合物地球物理识别的可靠性.

The seismic research on marine gas hydrate has made great development. The main subject is how to identify BSR correctly and predict the Gas Hydrate sediment physical parameters（For example： thickness, porosity, concentration, etc. ） On the basis of physical property analysis of marine rocks, seismic method is used to identify true and false BSR and predict physical property of hydrate-bearing sediments for recognition of gas hydrate in sea areas. Recently, great progress has been made in seismic researches on marine gas hydrate, which is showed in the following aspects： （1） for theoretical analysis of physical property, simple model has changed into complex model capable of simulating actual situations to the largest extent; （2） for seismic explorations, seismic methods have gone from conventional single- and multi-channel to multi-frequency, high-resolution 2D and 3D and multiple components; （3） for seismic data processing, conventional method has given way to ＂three highs＂ and pre-stack time offset processing with emphasis on BSR characteristics; and （4） for identification of gas hydrate and prediction of its physical property parameters, researches on velocity and amplitude have been replaced by AVO, multi-attribute discrimination, multi-elastic parameter and multi-property parameter inversions. Thanks to these new techniques and methods, investigations in gas hydrate in sea areas have been greatly striding forward, and reliability of geophysical recognition of gas hydrate has been significantly heightened.