现代地质2024，Vol.38Issue(4)：873-891,19.DOI:10.19657/j.geoscience.1000-8527.2024.092
成矿流体运移与就位及其构造控制机理:以胶东焦家金矿带为例
Migration and Emplacement of Ore-forming Fluids and Their Structural Controlling Mechanisms:An Example from Jiaojia Gold Belt in Jiaodong Peninsula
摘要
Abstract
Hydrothermal ore-forming system can be controlled by the migration and placement of ore-forming fluids induced by tectonic movement.Structure is the primary ore-controlling factor,and the migration and placement of ore-forming fluids are the core theory of tectonic ore-controlling.Multiple or single dominant fac-tors,such as fluid pressure differences,integrated hydraulic gradients,and heat conduction,drive fluid migra-tion within transport channels formed by faults,cracks,and pores in the surrounding rocks.Chemical reactions of fluids in structural cracks or pores,fluid mixing and immiscibility,and fluid boiling lead to changes in the physical and chemical properties of the fluids,resulting in the precipitation of ore-forming materials.Fluid mi-gration patterns affect the form of mineralization.Fluid migrating through macroscopic faults and fractures,re-sembling pipeline flow,primarily forms large vein ore bodies with high mineralization.However,permeation flow,which widely develops in micron-scale cracks and pores of surrounding rock,mostly forms fine veins and disseminated ore bodies with stable mineralization grade and medium scale.The dynamic coupling between tec-tonic deformation,fluid pressure,and stress state leads to the temporal and spatial occurrence of the ore body.The fault valve-pumping mechanism is the most representative tectonic-fluid coupling model to explain orogenic gold mineralization.The formation and distribution of deposits in the Jiaojia gold belt are controlled by three-or-der fault structures.The compression-shear Jiaojia fault is a first-order ore-controlling structure,which governs the extensive hydrothermal alteration dominated by sericitization and the placement of altered rock type gold ore bodies within fracture zones.The Wangershan fault,a tensile shear structure in its footwall,serves as a second-ary ore-controlling structure,where hydrothermal alteration is relatively weaker,resulting in the development transitional gold ore-body.The third-order ore-controlling structure consists of dozens of tensile-shear faults and joint systems dominated by the Baoli fault,which exhibits the weakest degree of alteration and mineralization.This structure mainly controls the occurrence of quartz vein-type gold orebodies.The study of the three-dimen-sional geometry of the ore-body in Sizhuang gold deposit shows that the morphological flatness of the ore-body group increase from No.1 ore body to No.Ⅲ ore body.This indicates the spatial evolution of ore-forming fluid transport from infiltration to pipeline flow,and the differences in ore-body occurrence reflect changes in ore-forming fluid migration directions.Further research needs to integrate results from multidisciplinary studies,es-pecially conducting in-depth analysis of the coupling relationship between micro-ultra-microscopic deformation fabric and ore-forming fluid behaviors.This includes constructing a multi-scale structure-fluid coupling ore-forming model that closely mimics reality and reveals the intricate processes and mechanisms of hydrothermal ore-forming system.关键词
热液成矿系统/成矿流体运移与就位/构造控矿/构造-流体成矿动力学/焦家金矿带Key words
hydrothermal ore-forming system/migration and emplacement of ore-forming fluids/structural ore-controlling/structure-fluid metallogenic dynamics/Jiaojia gold belt分类
天文与地球科学引用本文复制引用
张龙啸,杨立强,杨伟,谢东..成矿流体运移与就位及其构造控制机理:以胶东焦家金矿带为例[J].现代地质,2024,38(4):873-891,19.基金项目
国家自然科学基金项目(42130801) （42130801）
国家重点研发计划项目(2019YFA0708603) （2019YFA0708603）
高等学校学科创新引智计划2.0(BP0719021) （BP0719021）
中国地质大学深时数字地球前沿科学中心"深时数字地球"中央高校科技领军人才团队项目(2652023001) （2652023001）
地质过程与矿产资源国家重点实验室专项基金(MSFGPMR201804). （MSFGPMR201804）
