摘要
在重磁异常资料处理中,向下延拓处理是一种常用的处理方法,相对于传统的位场下延方法,正则化向下延拓可以有效抑制位场下延过程中的振荡效应。龙门山断裂带区域,是研究青藏高原新生代构造变化以及其隆升机制和印度板块相互碰撞作用关系的重要地区。这里利用重力异常数据正则化向下延拓处理方法,对龙门山断裂带的构造特征进行研究:首先通过理论模型实验论证了重力异常正则化下延的可行性和优势;然后选取了三条覆盖龙门山地区的典型地质剖面,并对各剖面的重力异常数据进行了位场下延处理。通过对位场下延60 km重力异常场断面分布特征的分析得出结论:明显的重力异常差异带为青藏高原东缘及龙门山构造演化过程的体现;由重力异常特点可以推断出龙门山构造带具有典型的推覆构造特征。
Downward continuation is a common method in the processing of gravity and magnetic anomaly data.Compared with the traditional potential field downward continuation method,the oscillation effect in the potential field downward continuation process can be effectively suppressed by regularization downward continuation.The Longmenshan fault zone is an important area to study the Cenozoic tectonic changes in the Qinghai-Tibet plateau and the relationship between its uplifting mechanism and the collision of the Indian plate.In this paper,the tectonic characteristics of the Longmenshan fault zone are investigated using the downcontinuation processing method of regularization of gravity anomaly data.Firstly,the feasibility and advantages of down continuation of gravity anomaly regularization are demonstrated through theoretical model experiments.Then three typical geological profiles covering The Longmen mountain area are selected and the potential field extension of gravity anomaly data in each profile is carried out.Through the analysis of the cross-section distribution characteristics of the gravity anomaly field extending 60 km below the potential field,it is concluded that the obvious gravity anomaly difference zone is the reflection of the tectonic evolution process of the eastern edge of the Qinghai-Tibet plateau and Longmen mountain.From the characteristics of gravity anomaly.This can be inferred that the Longmenshan structural belt has typical nappe structural characteristics.
作者
朱家富
王绪本
高永才
梁生贤
李军
ZHU Jiafu;WANG Xuben;GAO Yongcai;NIANG Shengxian;LI Jun(School of Geophysics, Chengdu University of Technology, Chengdu 610059, China)
出处
《物探化探计算技术》
CAS
2021年第5期655-662,共8页
Computing Techniques For Geophysical and Geochemical Exploration
基金
国家自然科学基金(91755215)。
关键词
重力异常
正则化向下延拓
青藏高原
龙门山
推覆构造
gravity anomaly
regularization downward continuation
Qinghai-Tibet plateau
Longmen mountain
nappe structure
