滑动扫描谐波的现场压制方法

Harmonics on-site suppression on vibroseis slip-sweep data

高密度宽方位三维勘探在成为主流地震勘探技术的同时,也带来激发成本的大幅度提高。应用滑动扫描能有效降低激发成本,提高施工效率。但可控震源激发本身存在的谐波因采用滑动而不可避免地干扰了相邻炮记录,因此压制谐波成为确保滑动扫描采集地震资料品质的前提。本文从可控震源激发的基本原理出发,分析了谐波产生的机理、谐波干扰的能量级别,并有针对性地设计滑动扫描相关参数,侧重压制滑动扫描产生的能量较强的二、三次谐波。试验及滑动扫描实际采集的地震资料显示本文的谐波压制方法效果良好。

As a main tool of high-density wide azimuth 3D seismic acquisition,vibroseis slip-sweep can effectively improve the productivity and reduce operation cost in the field.However,the inherent harmonics of multi-vibrations inevitably interfere with adjacent shot records due to application of slip-sweep.Therefore,the effectiveness of harmonics suppression has become the premise to ensure the data quality of slip-sweep recording.The paper approaches the generation mechanism of harmonics and the energy classification of harmonics by analyzing the basic principle of vibroseis excitation,propose target-oriented design with some parameters for slip-sweep,and focuses on the suppression of strong second and third harmonics.Both field tests and field data recordings show that this harmonics suppression method introduced obtains good results.