西藏撞多勒地区水系沉积物地球化学特征及其地质填图应用

西藏撞多勒地区位于班公湖—怒江缝合带西段南侧燕山晚期火山—岩浆弧带,经历了多阶段复合造山作用,各类地质体和构造形迹复杂多样。本文在总结1:5万水系沉积物地球化学特征及分布规律基础上,分析不同地质体中元素的背景值、标准离差、富集系数、变异系数。依据地球化学示踪作用原理,运用多元素背景值推断主要地质体的空间展布和构造形迹,制作As、Sb、Hg元素组合及Cr、Ni、Zn元素组合的衬值累加图分别解译构造和岩浆岩,厘清宏观地质体与微观元素之间的关系,进行地层划分、地质体圈定和断裂追踪,对区域地质填图起到了较好的辅助作用。

GEOCHEMICAL CHARACTERISTICS OF STREAM SEDIMENTS AND APPLICATION FOR GEOLOGICAL MAPPING IN ZHUANGDUOLE AREA,TIBET

Zhuangduole area in Tibet is geotectonically located in the volcanic-magmatic arc zone, south to western segment of Bangong-Nujiang suture zone, it was experienced multi-stage compound orogeny. Based on the geochemical characteristics and anomalies distribution of stream sediment geochemical survey at scale 1∶50000,it was studied about the geochemical characteristics of the different stratigraphic, which include the element background value, standard deviation, concentration coefficient, and coefficient of variability. On the basis of the geochemical tracing principle, it was employed multi-element background differentiation method to infer geological bodies and linear structures. The accumulate contrast map of As-Sb-Hg association is used to interpret structures, and the map of Cr-Ni-Zn association for magmatic rocks, and then they are applied for stratigraphic classification, delimit intrusion, tracking fault.