摘要
招远-平度断裂是胶东金矿集区三条超大型控矿断裂(三山岛、焦家及招远-平度断裂)之一。受地表第四系覆盖影响,金矿体空间赋存位置与主断裂及其次级断裂地表出露位置的耦合关系尚存问题。通过开展精细化处理区域重力和航空磁测数据,如空间域不同高度延拓(100 m、200 m和500 m)及垂向一阶导数等方法,发现招远-平度断裂地表出露位置与深部地球物理梯度带存在位移差,且位移差向断裂倾向方向南东侧移动趋势愈发明显,进一步证明招远-平度断裂深部倾向南东,倾角由浅至深逐渐变缓,局部变化剧烈的地质推论。同时,开展地表高精度1/10000比例尺的重力结果显示,重力异常曲线自西向东整体呈快速上升趋势,局部存在凹陷区,表明花岗质碎裂岩及绢英岩化花岗质碎裂岩密度(2.63 g/cm^(3))介于玲珑二长花岗岩(2.57 g/cm^(3))和古元古界(2.82 g/cm^(3))之间,含矿层位与围岩存在较大密度差,金矿体主要赋存于花岗质碎裂岩及绢英岩化花岗质碎裂岩层位的倾角由陡变缓或由缓变陡的转折部位,可分别发现石英脉型金矿和蚀变岩型金矿。
The Zhaoyuan-Pingdu fault is one of the three super large ore-controlling faults(Shanshandao,Jiaojia and Zhaoyuan-Pingdu)in the Jiaodong gold concentration area.Due to the coverage of Quaternary,the relationship between the spatial distribution of gold ores and the exposure of main and secondary faults has been still unsolved.This work conducted fine processing of regional gravity and aeromagnetic data in this area,such as upward continuation at different altitudes in spatial domain(100 m,200 m,and 500 m)and first vertical derivative.Results indicate that there is a displacement difference between the exposure of the Zhaoyuan-Pingdu fault and the deep geophysical gradient zone,and the displacement difference becomes significant along the southeast direction of the fault trend.It is further proved that the deep Zhaoyuan-Pingdu fault strikes southeast,and the dip angle gradually decreases from shallow to deep,with drastic local changes.High-precision surface gravity survey at a scale of 1/10000 shows that the gravity anomaly curves show a rapid upward trend from west to east,with local depression areas.The density of granitic and sericitized granitic rocks(2.63 g/cm^(3))is inferred to be between that of Linglong monzogranite(2.57 g/cm^(3))and Paleoproterozoic(2.82 g/cm^(3)).There is a significant density difference between the ore-bearing layer and the surrounding rock.The gold deposit mainly occurs in the dip angle of granitic and sericitized granitic rocks,which changes from steep to gentle or from gentle to steep,and quartz vein type and altered rock type gold deposits can be discovered in this area.
作者
许志河
丁正江
朱成
庞森瑞
范潍箐
XU Zhihe;DING Zhengjiang;ZHU Cheng;PANG Senrui;FAN Weijing(Development of Big Data Application for Deep Gold Mine Exploration at Shandong Engineering Research Center,Weihai,Shandong 264209;School of Earth Sciences,School of Disaster Prevention and Technology,Langfang,Hebei 065201;Engineering Research Center for Geothermal Resource Development Technology and Equipment,Ministry of Education,Changchun,Jilin 130000;Minmetals Exploration and Development Co.,Ltd.,Beijing 100010)
出处
《地质与勘探》
CAS
CSCD
北大核心
2024年第4期776-784,共9页
Geology and Exploration
基金
深部金矿探测大数据应用开发山东省工程研究中心(编号:SDK202221)
中央高校项目(编号:ZY2022024)
国家自然基金科学基金(编号:42372269)联合资助。
关键词
地球物理
2.5维反演
布格重力异常
剩余重力异常
控矿构造识别
招远-平度断裂
胶东金矿集区
geophysics
2.5 dimensional inversion
Bouguer gravity anomaly
residual gravity anomaly
identification of ore-controlling faults
Zhaoyuan-Pingdu fault
Jiaodong gold concentration area
