一种基于吸收衰减的覆盖次数设计方法

A Kind of Fold Designing Method Based on Absorption Attenuation

摘要: 随着物探技术的不断进步，地质上对地震勘探资料品质的要求越来越高。“两宽一高”地震勘探技术的规模应用，大幅度提升了地震勘探资料的品质，但是受勘探投资的制约，采集参数的设计、资料品质与采集成本之间需要保持平衡。勘探新区和勘探程度较低的区域受老资料少、勘探认识程度低的制约，采集参数的确定通常需要通过试验线资料对比得出，在理论方法论证方面仍缺乏定量分析，同时单一的试验线分析难以全面掌控全区资料品质变化。由于覆盖次数是影响采集参数的关键因素，为了更好地获得高品质资料，往往新区勘探覆盖次数设计都会较保守地设计较高覆盖，但过高的覆盖次数会提高采集成本，同时大量的冗余数据也为资料处理增加了不必要的工作量。本文提出了一种基于吸收衰减的覆盖次数设计方法，通过计算地震波的球面扩散、吸收衰减和反射能量，分析不同覆盖次数下信噪比的变化，为地震勘探采集设计覆盖次数优化论证提供参考。

Abstract: With the development of geophysical exploration technology, the quality of seismic exploration data is required more and more. The large-scale application of wide azimuth, wide frequency band and high density technology greatly improves the quality of seismic data, but restricted by exploration investment, the design of acquisition parameters, data quality and acquisition cost need to be balanced. New exploration areas and less explored areas are restricted by the lack of old data and low exploration awareness, so the determination of acquisition parameters usually needs to be obtained through comparison of test line data, which still lacks quantitative analysis in theoretical and methodological demonstration, and at the same time, it is difficult for a single test line analysis to comprehensively control the data quality changes in the whole area. As the number of coverage is a key factor affecting acquisition parameters, in order to better obtain high-quality data, the design of exploration coverage in new areas is usually a conservative design with high coverage, but too high coverage will increase acquisition cost, and a large number of redundant data will also increase unnecessary workload for data processing. In this paper, a design method of coverage times based on surface absorption attenuation is proposed. By calculating spherical diffusion, absorption attenuation and reflection energy of seismic wave, the change of signal-to-noise ratio with different coverage times is analyzed, which provides reference for optimization demonstration of coverage times in seismic exploration acquisition design