云南格咱岛弧印支期地壳隆升与剥蚀及其地质意义:来自黑云母矿物压力计的证据  

The Indosinian Crust Uplift-Denudation in Geza Arc of Yunnan Province and Its Geological Significance: Evidence from Biotite Geobarometer

作　　者：刘学龙[1,2] 李文昌[1,2,3] 尹光侯 

机构地区：[1]中国地质大学地球科学与资源学院,北京100083 [2]昆明理工大学国土资源工程学院,云南昆明650093 [3]云南省地质调查局,云南昆明650051

出　　处：《现代地质》2013年第3期537-546,628,共11页Geoscience

基　　金：国家重点基础研究发展计划"973"课题"巨型矿床形成保存及资源潜力"(2009CB421007);中央高校基本科研业务费专项资金资助项目(2011PY0154);中国地质调查局项目(1212011085137)

摘　　要：区域的隆升与剥蚀是影响成矿岩体形成后变化与保存的主要因素,矿物压力计能定量获取花岗质岩浆初始结晶时的压力条件,是研究花岗岩体形成深度及隆升剥蚀历史的有效手段之一。应用黑云母的TAl地质压力计,计算了云南格咱岛弧岩浆岩带印支期典型成矿斑岩体侵位的深度,并估算了格咱岛弧地区地壳的隆升与剥蚀速率,探讨了矿床形成后变化及保存的情况,结果表明印支期以来格咱岛弧地区的成矿岩体剥蚀速率较小,平均为0.018 mm/a,这对矿床形成后的保存较为有利。研究结果为探讨滇西高原印支期以来的构造隆升—剥蚀提供了定量参考。Regional uplift and denudation is one of the main factors that have effect on the changes and preservation after deposit formation.Mineral geobarometer can quantitatively obtain the initial crystallization pressure of granitic magma,which is also one of the effective methods to reflect granitic intrusion depth and uplift history.In this paper,we apply biotite TAl geobarometer to calculate the emplacement depth of typical ore-forming porphyries in Geza magmatic belts in Indosinian and to estimate the crust uplift-denudation rates.Also,we discuss the changes and preservation after deposit formation.The results indicate that the denudation rate of ore-bearing intrusion is rather slow with an average value of 0.018 mm/a,which is favorable to preserve the deposit after its formation.Our study also provides a quantitative reference for the tectonic uplift and denudation of the western Yunnan plateau since Indosinian.

关 键 词：地壳隆升 剥蚀速率 变化与保存 壳幔作用 格咱岛弧 云南 

分 类 号：P578.959[天文地球—矿物学] P588.1[天文地球—地质学]