基于航磁资料对智利塔拉帕卡地区的构造解释及意义

On the geological structures and significance based on the aeromagnetic data in the Tarapaca District,Chile

智利塔拉帕卡地区西部阿卡塔玛和东部多明戈断裂系统控制了塔拉帕卡地区自西向东迁移的构造-岩浆活动和成矿类型.本文对智利塔拉帕卡地区航磁数据进行处理和解释,揭示了该地区近南北向、北西向和近东西向区域性深大断裂构造的位置及平面分布特征,查明了塔拉帕卡地区火山机构基本上沿着深大断裂系统边界分布;确定了该地区大型斑岩矿床大多分布于磁异常和居里面变化的梯度带上、断裂系统的边缘部位及火山机构周边的规律;分析了阿卡塔玛和多明戈两大区域断裂系统形成原因,探讨了智利北部地区断裂构造系统与岩浆活动关系.为研究智利塔拉帕卡地区的地质、构造特征以及圈定找矿远景区提供基础性信息.

The Acatama fault system in the west and the Domeyko fault system in the east in the Tarapaca region of Chile controlled the tectonic-magmatic activities migrating eastward and the types of mineral resources.In this paper,we processed the aeromagnetic data of the Tarapaca area of Chile and achieved some conclusions based on the interpretation of the processing results.We revealed the locations and planar distribution characteristics of the regional deep faults along the directions of near NS,NW,and near EW in this area.We found the volcanic institutions in the Tarapaca region mainly distributed along the boundaries of the regional faults.We ascertained the features that most of the large porphyry deposits in this area are distributed on the steep gradient belts of magnetic anomalies and Curie point depth variations,the edges of the regional fault systems,and the areas around volcanic institutions.We analyzed the formation of the Acatama and Domeyko fault systems,deduced the relationship between fault structure and magmatic activity in northern Chile.Our research provides some basic information for the study of the geological and tectonic characteristics of the Tarapaca area of Chile and the delineation of prospecting prospects.