花岗质岩浆侵位的构造物理模拟研究进展  

Advances on the Analogue Modeling of the Emplacement of Granitic Magma

作　　者：李盈莹 王博[1] 曹婷婷 LI Yingying;WANG Bo;CAO Tingting(State Key Laboratory for Mineral Deposits Research,School of Earth Sciences and Engineering,Nanjing University,Nanjing 210023,China)

机构地区：[1]内生金属矿床成矿机制研究国家重点实验室,南京大学地球科学与工程学院,南京210023

出　　处：《高校地质学报》2023年第4期543-558,共16页Geological Journal of China Universities

基　　金：国家自然科学基金(42161144013;41927802;41772225);中央高校基本科研业务费专项资金(XJ2022001001)联合资助。

摘　　要：构造作用产生的变形空间是花岗质岩浆上升和侵位的重要通道,岩体就位后的最终几何形态也会受到构造变形的控制。构造物理模拟实验是研究岩浆侵位过程的重要方法,文章梳理了前人在岩浆侵位物理模拟实验中常用的实验装置、实验材料和实验相似性原则,总结了不同构造环境下各构造要素对岩体几何形态的影响并指出:(1)构造平静期(前构造静态条件下)岩体形态主要受控于围岩的性质;(2)在构造活动期(同构造动态条件下),围岩厚度与流变学分层、变形速率与总变形量、岩浆注射速率与总注射量、岩浆注射通道的位置、岩体侵位与构造活动的相对先后关系等因素都会影响到岩体的最终形态和浅部围岩的构造变形样式,同时浅部构造变形又会反过来影响岩体的几何特征;(3)在不同构造环境下,变形速率与注射速率、围岩流变学分层等因素对岩体形态的影响总体一致。此外,文章还介绍了岩浆侵位物理模拟研究的若干局限性,并提出工业CT扫描技术和数值模拟方法可以作为岩浆侵位物理模拟实验研究的有益补充。Regional tectonics not only facilitate the ascent and emplacement of the granitic intrusions but also control the final shapes of the intrusions.Analogue modeling is a critical method to study the magma emplacement.This paper reviewed the experimental set-up,materials and scaling used in previous analogue models related to magma emplacement,and summarized the influence of various parameters on the geometry of the intrusions in various tectonic settings.We suggested that:(1)the intrusion geometry is controlled by the characteristics of the country rocks in pre-kinematic static settings during tectonic quiescent stage.(2)In syn-kinematic settings during tectonic active stage,the intrusion geometry and deformation patterns of plutons are influenced by several parameters,including the thickness and rheological layering of the country rocks,velocity and total distance of displacement,velocity and total volume of magma injection,position of the injection inlet(magma channel),relative timing of tectonic activity and magma emplacement.Deformation can in turn control the shape of intrusions.(3)The parameters,such as displacement velocity and injection velocity in different settings,have similar impact on the intrusion geometry.In addition,some limitations of analogue modeling method are also discussed.The CT technique and numerical modeling methods are suggested to be profitable supplementation of analogue modeling for the study in magma emplacement.

关 键 词：花岗质岩浆 岩浆侵位 岩体形态 构造控制作用 物理模拟 研究进展 

分 类 号：P619.222[天文地球—矿床学]