Geological Features And Prospecting Indicator Of The Bayantuga Fluorite Deposit,Abaga Qi,Inner Mongolia

Abaga Banner is located in the central and eastern part of Inner Mongolia,and the tectonic location of this region is in the middle of the Central Asian Orogenic Belt.This area is a favorable location for fluorite mineralization,with great potential for mineralization and prospecting.This work takes the Bayantuga fluorite deposit as the research object,and studies the structure,strata,magmatic rocks and ore-forming fluids in the study area in combination with modern mineralization and metallogenic prediction theory.Using gravity anomaly,aeromagnetic anomaly,geochemical anomaly,magnetic method and electrical method to study the combination of prospecting methods to predict metallogenicity and delineate the metallogenic target area.The obtained knowledge is as follows:(1)Regional NE-trending brittle faults play an important role in controlling the distribution of rock mass and strata,and are important ore-conducting structures.The secondary NW-trending faults that appear in groups beside the main NE-trending fault are important ore-hosting structures.(2)Micro-temperature measurement of fluorite fluid inclusions was carried out.The homogeneous temperature of the inclusions was between 107 and 180 °C,and the average homogenization temperature was 134 °C;the salinity of the ore-forming fluids ranged from 0.87 to 8.13 wt.% NaCl equiv;The density of the ore-forming fluid is0.89?0.96g/cm3,and the average value is 0.94g/cm3.The ore-forming fluid is mainly characterized by low temperature,low salinity and low density.It is speculated that the fluorite deposit is a low temperature epithermal deposit.(3)The Bayantuga fluorite deposit has experienced three stages of hydrothermal activity.The early stage is characterized by the output of fluorite-bearing quartz veins or irregular opal;the middle stage is the main formation of the Bayantuga fluorite deposit.In the mining stage,the fluorite formed is mostly symbiotic with quartz minerals to form fluorite-quartz veins,or filled between broken breccias in the form of hydrothermal cementation;late stage hydrothermal activity is mainly manifested as calcite veinlets or nets The veins are superimposed on the ore bodies formed earlier.(4)NW-trending tectonic fracture zone is an important prospecting marker,especially where fluorite,silicification,limonite,carbonate and kaolinite are commonly developed,where industrial ore bodies are likely to be formed.Gradient zones or distorted parts of magnetic field changes reflect the existence of deep hidden fault structures,and magnetic anomalies are signs of the existence of hidden faults.(5)Four metallogenic belts(?,?,?,?)were delineated by using geophysical anomalies and geochemical anomalies combined with actual geological conditions,and the existence of fluorite ore bodies was found through actual verification.