可控震源扫描模型优选设计法

AN OPTIMUM DESIGN OF VIBROSEIS SWEEP MODEL

地质矿产部西南石油地质局零五工程处

本文在假设地层吸收衰减量与非线性扫描补偿量相等的前提下,从理论上推导出可控震源扫描模型的函数关系,并采用优选法与抛物线插值法,经过四次试验,求出最佳离散扫描参数.文中还以实例讨论了设计步骤;对扫描瞬时输出能量作了图形剖析.此法只要求设计者了解工区地质情况和干扰波特征,所有计算工作均可在小型计算器上完成.本方法具有设计步骤简单,周期短,参数优化的特点.

On the consumption of formational absorption decay being B= -27.3φ-1fT and non-linear sweep compensation are identical in degree, the authors have derived theoretically the VIBROSEIS sweep model in the sense of function. And the optimum discrete sweep parameter could be determined by using the optimum seeking method and parabolical interpolation through 4 experiments. In the paper, the designing steps taken are also discussed with examples. A graphical analysis is made with respect to the transient sweep output.The approach presented just requires the geological situation of the area under survey as well as characteristics of interference wave, that the designer should have them in their minds. That’s all, Also, we can tell for sure that all the computations could be performed with mini-computer. What’s more, the said approach is characterized with: easy in designing procedures; quick in turnaround and optimized in selecting parameters.