摘要
研究川西地区可能控制火山岩相带的深大断裂以及火山岩的分布范围、深度等基础问题。利用最新大比例尺重磁资料,对数据进行斜磁化、剩磁处理和场源分离,采用物性反演方法进行反演,利用互相关系数和深度加权函数同时进行自约束,引入迭代正则化的LSQR法求解大型离散不适定问题以节省计算成本;采用正演模拟计算并确定了重磁资料主要解决的相关地质问题,即重力数据主要用于解译测区内具有密度差异的断裂构造,磁测数据主要用于预测火山岩;有针对性地采取响应的定性分析或三维反演成像,综合解译深层断裂构造、预测火山岩分布范围和埋深,并且根据已施工钻井对解译成果进行评价。火山岩埋深预测结果的最小相对均方误差仅0.86%,绝大多数情况下小于10%;重力资料能更好地反映深大基底断裂,而磁测资料对于火山岩的反应更为明显。
Based on the latest large-scale gravity and magnetic data,the basic problems of the deep and large faults controlling the volcanic facies in western Sichuan and the distribution range and depth of volcanic rocks are studied.Firstly,the gravity and magnetic data after oblique magnetization,remanent magnetization and field source separation were used for physical property inversion.Then the self-constraint is carried out by using the mutual relation number and the depth weighting function,and the iterative regularization LSQR method is introduced to solve the large discrete ill-posed problem to save the computing cost.The forward modeling determined the relevant geological problems to be solved by the gravity and magnetic data,that is,the gravity data were mainly used to interpret the fault structures with density differences in the test area,and the magnetic data were mainly used to predict volcanic rocks.The qualitative analysis or three-dimensional inversion imaging of the response is used to comprehensively interpret the deep fault structure,predict the distribution range and burial depth of volcanic rocks,and evaluate the interpretation results based on the drilling results.The results show that the minimum relative mean square error of volcanic rock depth prediction is only 0.86%,and in most cases less than 10%.The gravity data can better reflect the deep and large basement faults,while the magnetic data reflection is more obvious for volcanic rocks.
作者
潘力
何青林
陈康
梁生贤
朱家富
陈先洁
张富利
张晨
何昌兴悦
PAN Li;HE Qinglin;CHEN Kang;LIANG Shengxian;ZHU Jiafu;CHEN Xianjie;ZHANG Fuli;ZHANG Chen;HE Changxingyue(College of Geophysics,Chengdu University of Technology,Chengdu 610059,China;Exploration and Development Research Institute,PetroChina Southwest Oil and Gas Field Company,Chengdu 610051,China;Chengdu Center of China Geological Survey,Chengdu 610081,China)
出处
《成都理工大学学报（自然科学版）》
CAS
CSCD
北大核心
2023年第2期240-248,共9页
Journal of Chengdu University of Technology: Science & Technology Edition
基金
中国石油西南油气田分公司科技重大专项(2019ZD01)。
关键词
四川盆地
火山岩
重力
磁法
断裂构造
Sichuan Basin
volcanic rock
gravity
magnetic method
fault structure
