Gravity Measurements Reveal Concealed Rock Masses Surrounds Molybdenum Deposit

摘要

Daqinggou molybdenum deposit is an important part of the eastem Qinling molybdenum belt which locates in daqinggou miaozi village area,luanchuan county,Henan province.This is also a part of the Huaxiong margin depression in the North China Platform and it is considered to be a favorable metallogenic area because of the intense tectonic movement and frequent magrnatic activities.This molybdenum deposit is a medium-sized deposit and the ore bodies are strictly controlled by stratum,lithology,structures and environment of ancient geography as well as magmatic rocks.The author compares the difference of physical properties in the first place,then divides research area into two abnormal areas (North and South) and identifies four density layers and three interfaces in the vertical direction with bouguer gravity anomaly.Secondly,It is found that there includes two first level and ninety-eight second level faults.Particularly,there are fifty faults toward NW-NWW,forty faults toward NE-NNE,four faults toward EW and the last six faults toward SN.Different types of data processed gravity maps are analyzed and it is clearly seen that sharp contrasts locate in Linear extreme zone from horizontal direction derivative,dislocation interfaces in gravity anomaly curves,Linear gradient belts from bouguer gravity anomaly.According to some geological data and second derivative gravity map,it is also inferred that there are three hidden rock masses in research area which are G5 low density anomaly,G6 low density anomaly and G9 low density anomaly between Caledonian Iron rich ekerite and the location of north Taihua group.Last but not least,Gravity prospecting marks are summarized in this paper.In conclusion,this research plays an important role in selecting prospecting target area in hidden porphyry type polymetallic molybdenum deposit which belongs to eastern Qinling Mountains-Dabie Mountains molybdenum ore belt and providing reliable evidences for the expansion of old molybdenum mine.