确定性反演和随机反演对井约束条件的需求分析

A comparison between the requirements of multi-well constrained conditions in deterministic inversion and stochastic inversion

(1.北京大学地球与空间科学学院，北京100871；2.同济大学海洋地质国家重点实验室,上海200092)

Pan Yujie,State Key Laboratory of Marine Geology (Tongji University),Shanghai 200092,China

叠后数据地震反演一般利用测井信息对反演结果进行约束,不同的反演方法对井约束条件的需求存在差异,不恰当地使用井约束条件将严重影响反演结果的准确性。基于理论数据分析了确定性反演和随机反演中多井约束对反演精度的影响。研究表明，在确定性反演中,多井约束将导致反演结果可信度降低,相比多井约束的反演结果,单井约束更能准确描绘出相对阻抗差异;在随机反演中,约束井数目越多,不确定性越低,反演精度越高。

During the seismic inversion of post-stack data,logging data is usually used to constrain the inversion result.Different inversion methods require different well-constrained conditions,and inappropriate application of well-constrained conditions will seriously impact the accuracy of inversion.By utilizing synthetic data,we analyzed the impact of multi-well constrained conditions on deterministic inversion and stochastic inversion.The results indicate that in deterministic inversion,multi-well constrained conditions will decrease the reliability of inversion,and single-well constrained condition can accurately reflect the contrast of relative impedance;in stochastic inversion,more constrained wells cause lower uncertainty and higher inversion accuracy.

10.3969/j.issn.1000-1441.2011.04.005