基于实际地震资料的覆盖次数和信噪比关系分析

Analysis of the relationship between fold and SNR based on actual seismic data

1.中国石油化工股份有限公司胜利油田分公司物探研究院,山东东营257022;2.中国石油化工股份有限公司胜利油田分公司,山东东营257022

Xu Hui,Geophysical Research Institute of Shengli Oilfield Branch Co.,Dongying 257022,China

目前高精度三维地震资料采集中采用多高的覆盖次数既能达到所希望的信噪比,又能合理地控制采集投资是必须考虑的实际问题。以永新地区高精度实际地震资料为基础,通过对该区细分面元的观测系统进行退化处理,选取了8种覆盖次数相对均匀、属性较好并且在野外可以实现的观测系统作为研究基础,利用频谱估算的信噪比计算方法,对相同面元不同覆盖次数、不同面元相同覆盖次数以及不同噪声背景下的资料进行信噪比分析和统计,研究了覆盖次数与信噪比的关系曲线,并根据实际统计曲线,得出结论:①信噪比与面元的大小基本无关,只与覆盖次数有关;②不同面元覆盖次数相同,信噪比一致;③高精度三维地震资料采集覆盖次数选择在200次左右。

In highprecision 3D seismic data acquisition,the fold must be chosen to achieve the expected SNR as well as to reasonably control the cost.On the basis of the actual highprecision seismic data in Yongxin area,by the degradation processing on the divisiblebin geometry,eight geometries were selected which had relatively even fold and better properties and could be deployed in the field,we utilized frequency spectrum estimation method to carry out analysis and statistics on SNR under the conditions of same bin with different fold,different bin with the same fold and different noise background,studied the relationship of fold and SNR.In terms of the actual statistics curve,the conclusions can be achieved: ① the SNR is related to fold and almost has nothing to do with bin size;②the SNR of different seismic data is the same if the fold is the same;③ the fold of highprecision 3D seismic data should be about 200.