摘要
在进行瞬变电磁数据一维反演时,如何合理选取初值对反演结果影响较大。文中利用视纵向电导能够划分电性层位的优势,根据视深度—视纵向电导曲线特征,结合视深度—似电阻率和视深度—全区电阻率曲线,相互对比,确定曲线拐点;根据拐点个数给出层数,再利用拐点对应的坐标值选取层参数。以此作为一维线性反演的初始模型进行反演。试算结果表明,当初值选取合理时,利用常规的线性反演方案就可使反演曲线获得快速、稳定收敛和等值性减小的效果。
When conducting transient electromagnetic one-dimensional inversion, how to select initial value has a great impact on inversion result. In this paper the advantage of apparent vertical conductance classifying electrical property layer was utilized, then based on characteristics of apparent depth-apparent vertical conductance curve and by integrating apparent depth-apparent resistivity with apparent depth-smoking-ring resistivity curve, the curves were correlated and analyzed and the turning points of the curves were determined, then the layer number were calculated from the number of the turning points and the layer parameters were obtained from the coordinates of the turning points, at last inversion was conducted based on the one-dimensional linear inversion initial model. Trial calculation results show that the general inversion approach converges fast and can reduce equivalence effects when the initial model parameter is reasonable.
出处
《石油地球物理勘探》
EI
CSCD
北大核心
2010年第2期295-298,共4页
Oil Geophysical Prospecting
基金
大型油气田及煤层气开发科技重大专项(2008ZX05019-007)
国土资源部公益项目(08Z11101)
关键词
瞬变电磁
视纵向电导
一维反演
烟圈
初值
transient electromagnetic method
apparent vertical conductance
one-dimensional inversion
smoking ring
initial parameter
