西北地质2025，Vol.58Issue(3)：63-74,12.DOI:10.12401/j.nwg.2024107
祁连造山带东段覆盖区重磁场特征及北中祁连构造边界划分
Gravity and Magnetic Field Characteristics in the Covered Area of Eastern Segment of the Qilian Orogenic Belt and the Delineation of the Northern and Central Qilian Tectonic Boundaries
摘要
Abstract
The eastern segment of the Qilian orogenic belt is situated at the northeastern edge of the Qinghai-Tibetan Plateau,intersecting with the Alxa Massif and Ordos Massif.This region also serves as a transitional zone between the Qinling orogenic belt and the Qilian orogenic belt.The tectonic framework in this region is highly complex,and the current understanding of the boundaries between the north Qilian and central Qilian tec-tonic units remains relatively limited.In this study,we applied the normalized vertical derivative of the total hor-izontal derivative(NVDR-THDR),minimum curvature field separation,and wavelet multi-scale decomposition to process and analyze Bouguer gravity anomalies and the magnetic anomalies reduced to the pole.By integrat-ing regional geological characteristics,we inferred four primary faults and fifty-four secondary faults.The pri-mary faults delineate the boundaries of tectonic units.Specifically,the boundary between the Qilian and North Qilian tectonic units is traced by a linear segment connecting Ping'an-Ledu-Dingxi-Zhangjiachuan,correspond-ing to the northern edge fault of the Qilian Mountains.Furthermore,there exists a prominent first-class tectonic unit known as the north Qilian accretionary wedge between central Qilian and north Qilian units.The eastern coverage area of the Qilian orogenic belt can be divided into three tectonic units:the northern Qilian island arc belt,the Northern Qilian accretionary wedge,and the central Qilian rogenic belt.关键词
断裂/构造单元/重磁异常/小波多尺度分析/覆盖区/祁连造山带东段Key words
faults/tectonic units/gravity and magnetic anomaly/wavelet multiscale decomposition/cover-age area/the eastern segment of Qilian orogenic belt分类
地质学引用本文复制引用
杨柳,冯旭亮,张健,柴培琪,马佳月..祁连造山带东段覆盖区重磁场特征及北中祁连构造边界划分[J].西北地质,2025,58(3):63-74,12.基金项目
国家自然科学基金项目"基于不同范数的密度界面三维重力反演研究"(41904115),甘肃省地质矿产勘查开发局第一地质矿产勘查院委托课题"甘肃省会宁-庄浪一带覆盖区异常查证及靶区优选"(0102/290023098)联合资助. （41904115）
