摘要
海上地震勘探大多使用气枪或气枪阵列作为震源激发地震波。气枪阵列是由多条气枪组合而成的,具有一定的长度和宽度,同时由于数据采集现场条件的限制,所设计的气枪阵列很难达到严格的圆对称空间布局,从而使得气枪阵列不满足点震源的假设,其激发子波的能量随传播方向的变化而变化。本文依据气枪阵列远场子波合成原理,引入三维极坐标系,综合考虑气枪阵列的空间布局及虚反射的影响,推导出气枪阵列子波方向性的计算方法;基于实际气枪阵列,利用该方法针对气枪阵列子波与水平方位角和垂直方位角的关系,以及子波能量在三维空间中的分布情形等进行了细致分析。
As main seismic source,air-gun or air-gun ar-ray is used in marine seismic exploration.Air-gun array composed of a number of air-guns has certain length and width.With the restriction of ship and field conditions,a designed air-gun array is difficult to form a circular symmetry space.All these factors make it hard to meet point source hypothesis.So wavelet energy of the air-gun array always changes with transmission direction.Based on the principle of air-gun far-field signature composition, we deduce in this paper a method of calculating the air-gun array directional energy by introducing 3-D polar coordinate system,the space layout of airgun array,and ghost.With this method,we analyze the relations between air-gun array signature and lateral and vertical azimuths,and the energy distribution of the signature.
出处
《石油地球物理勘探》
EI
CSCD
北大核心
2014年第2期236-238,217,共3页
Oil Geophysical Prospecting
基金
中国石油东方地球物理公司课题"气枪阵列设计优化软件的完善和推广应用"(12-08-05-2013)资助
关键词
海上地震勘探
气枪阵列
子波方向性
虚反射
远场子波合成
点震源
marine seismic exploration,air-gun array,signature directivity,ghost,far-field signature composition,point source
