西秦岭国安寺—白杨沟地区高精度磁测异常特征及找矿远景分析

Characteristics of ground magnetic anomalies and exploration perspective analysis in Guo'an temple-Baiyanggou area of west Qinling

研究区位于西秦岭东段的凤太矿集区内.在系统搜集和研究陕西凤太地区前人地质资料成果的基础上,结合本次1/5万地面高精度磁法测量资料,以金、铅锌矿为主要目标,整体评价研究区矿产资源潜力.研究区地面高精度磁测结果表明:该区自西向东可分为西部正磁异常区、中部平静磁异常区和东部负磁异常区,弱磁异常与区内广泛分布的沉积地层有关,"西高东低"的磁场变化特征与磁性基底的起伏形态有关.共圈定17处磁异常,磁异常按从西到东、由北往南的顺序依次进行编号,分别为M1、M2……M17,这些磁异常有的与磁性基底有关,有的属于隐伏磁性体,有的与磁黄铁矿化蚀变有关,其中磁黄铁矿化蚀变间接对寻找区内八卦庙式金矿具有指示意义.通过对全区磁异常特征的研究并结合相关地质资料,划分成矿远景区两处,为以后找矿提供思路分析,可作为寻找铅锌金-多金属矿的远景区.

The study area is located in the Fengtai ore-concentrated area,eastern part of west Qinling. Based on the systematically collecting and further studying on the previous geological data,this paper overall evaluate the mineral resources potential by analysis of the 1 ∶ 50000 ground high precision magnetic survey in Shaanxi Fengtai area,with the main purpose of gold and lead-zinc deposits.The ground high precision magnetic survey results showed the study area can be divided into the western positive magnetic anomaly,the central quiet magnetic field and eastern negative magnetic anomaly zones. The weak magnetic anomalies are related to the widely distributed sedimentary formations in the area. The ＂high in the west and low in the east＂magnetic field variations are related to the fluctuating magnetic basement. Seventeen magnetic anomalies can be delineated,and numbered consecutively with M1-M17 from west to east,and north to south. Some of which are related to the magnetic basement,some are related to the buried magnetic bodies,and some are related to the pyrrhotitezation alteration zone. The pyrrhotitezation alteration can indirectly provide indicative significance for Baguamiao-type gold deposits＇ prospecting. Based on the related geological data and the ground magnetic anomaly characteristics,two metallogenic prospect zones can be delineated for lead-zinc-gold polymetallic mines prospecting,and can provide theoretical basis for the searching mineral resources in the future.