厄瓜多尔西海岸天然气水合物地震识别方法及其分布规律  

Seismic identification methods and the distribution rule of gas hydrates in the Western Coast of Ecuador

作　　者：刘培栋[1] 王锡文[2] 袁洪仁 邓国振[2] 王勇[3] 薛超[1] 

机构地区：[1]中国石化中原石油工程有限公司海外工程公司,濮阳457001 [2]中国石化中原油田分公司物探研究院,濮阳457001 [3]中国石化中原石油工程有限公司钻井三公司,兰考475300

出　　处：《地球物理学进展》2016年第4期1633-1638,共6页Progress in Geophysics

基　　金：厄瓜多尔国家石油公司"厄瓜多尔西海岸地区二维地震资料处理;解释和综合地质研究"的部分研究内容(2008116)资助

摘　　要：天然气水合物是一种潜在的巨大新型能源,目前成为科学家们关注的焦点,并积极开展这方面的研究工作.天然气水合物可通过地质沉积物取样、钻探取样和深潜考察等方法来直接识别,也可通过似海底反射层(BSR)、速度和振幅异常结构、地球化学异象、多波速探测和海底电视摄像等间接手段来识别.由于深海钻探十分昂贵并且有限,地震方法是大面积识别海洋天然气水合物的可靠手段.厄瓜多尔西海岸盆地是在板块作用下形成的沿海岸线状排列的弧前盆地,蕴含着丰富的石油和天然气资源,但整个地区勘探程度相对较低.通过在该地区开展地震地质综合研究,发现厄瓜多尔西海岸地区海上地震剖面上存在明显的BSR特征,本文采用平行海底反射、空白地震反射带、极性反转、AVO分析等方法和手段对该地区的天然气水合物进行识别,首次在厄瓜多尔西海岸地区确定了天然气水合物的分布范围及面积;同时通过成藏条件分析,采用Gornitz容积法公式计算出了该地区天然气水合物的资源量,揭示了其平面展布规律;因其巨大的资源量,表明了该地区广阔的勘探前景.Gas hydrates are a potentially huge and new energy,now it has become the focus of attention for scientists,and they have actively carried out research work in this aspect. Gas hydrates can be directly identified through geological deposits sampling,drilling sampling and deep-dive inspection,etc.,can also be indirectly identified by bottom simulating reflector（ BSR）,the velocity and amplitude anomaly structure,geochemical anomalies,multi-wave velocity sounding and seabed television camera. Because deep drilling is very expensive and limited,seismic methods are reliable means of identifying marine gas hydrates by large scale. Western Coast basin of Ecuador is a forearc basin arranged along the coastline under the action of the plate. Since the oil and gas exploration at the beginning of last century, there is nearly a hundred years of history for oil and gas exploration in the Western Coast of Ecuador, and a number of oil and gas fields was discovered, which are rich in oil and natural gas resources.However,the degree of exploration throughout the Western Coast of Ecuador is relatively low. Through integrated study of geophysics and geology in the area,it’s found that BSR feature is significant on the offshore seismic section in Western Coast of Ecuador,by using the methods of Bottom simulating reflector,blank seismic reflection zone, inverse polarity, AVO analysis to identify gas hydrates in this paper,the distribution scope and the size of the area for gas hydrates are clearly measured and defined in Western Coast of Ecuador for the first time; meanwhile through the analysis of potential petroleum systems and by using the volumetric method of Gornitz formula,the amount of gas hydrates resources was finally calculated in the area,its planar distribution rule was discovered;because of the huge amount of resources,the broad exploration prospects were indicated for the area.

关 键 词：天然气水合物 地震 似海底反射 极性 空白反射带 资源量 

分 类 号：P631[天文地球—地质矿产勘探]