对深层地震勘探中随机噪音的一点认识

Some cognitions on random noise in deep-layer seismic exploration

胜利石油管理局地球物理勘探开发公司,东营257100

Geophysical Exploration and Development Company, Shengli Petroleum Administration, Dongying 257100

在地震勘探过程中,随机噪音是影响地震资料信噪比的主要因素之一,尤其是对能量弱、频率低的深层地震信号。与有规律的线性干扰相比,随机噪音没有固定的视频率和视速度,但在一定的区域范围内,这类干扰又是遵循统计规律的。因此,深入地调查和分析工区内随机噪音的特征及其与施工因素的关系,对于更好地指导野外数据采集具有实际意义。本文结合胜利探区深层试验资料,主要对随机噪音中的环境噪音和次生噪音的特征及其与施工因素的关系进行了定量分析和统计,获得了一点认识,并提出了一些行之有效的压制方法,在实际生产中收到了一定的效果。

In seismic prospecting, random noise is one of main factors affecting the S/N ratio of seismic data, especially for deep layer seismic signals of weak energy and low frequency. Compared with regular linear disturbance, random noise has no solid apparent frequency and apparent velocity. But it comforms to statistical law in a certain areal extent. Therefore, deeply investigating and analyzing the character of random noise in working area and its relation with working factor have practical implication to better guiding field data acquisition. This paper makes a quantitative analysis and statistics primarily on the characters of environment noise and secondary noise as well as their relation with working factor by using deep layer testing data in the Shengli prospecting area. Some cognitions are derived, and a few effective noise suppression methods are put forward, which have brought certain effects in actual production.