CAJ | 학술논문

Occam 反演具有可靠性和加上各种先验信息可行性的优点，但是因为求取拉格朗日乘子需要很长时间，所以前人提出了几个直接选取方法。笔者改进了二维大地电磁测深 Occam 反演中求取拉格朗日乘子的方法。在搜索过程中加上观测数据拟合差与其期望值的比较。这样，在 Occam 反演的拟合差下降阶段的最后迭代和模型光滑阶段，能够排除多余的正演计算。这种改进对反演结果没有影响，但却使得反演速度加快并且更符合于 Occam 思想。根据模型实验和野外数据处理，可以减少正演次数20％～50％。
Occam 반연구유가고성화가상각충선험신식가행성적우점，단시인위구취랍격랑일승자수요흔장시간，소이전인제출료궤개직접선취방법。필자개진료이유대지전자측심 Occam 반연중구취랍격랑일승자적방법。재수색과정중가상관측수거의합차여기기망치적비교。저양，재 Occam 반연적의합차하강계단적최후질대화모형광활계단，능구배제다여적정연계산。저충개진대반연결과몰유영향，단각사득반연속도가쾌병차경부합우 Occam 사상。근거모형실험화야외수거처리，가이감소정연차수20％～50％。
Occam’s inversion is reliable and able to incorporate varying levels of the priori information.The Choice of Lagrange multiplier is computationally expensive and some direct selection methods are then suggested in this paper.We modified the selected method of Lagrange multiplier in 2D magnetotelluric Occam’s inversion.In the search progress,the misfit between the forward model response and observed data are added and compared with the target level.This can eliminate superfluous forward calculation in the last iteration of the phase of bringinge misfit down and the phase of smoothing out the unnecessary structure.This modification can accelerate inversion and more accordant with the Occam’s idea.Through inversions of several synthetic and field data,it is improved that forward caculation number can be reduced to 20% 50%.