藏南马扎拉金锑矿床电性结构特征与地质解译

Electrical properties and geological interpretation of the Mazhala goldantimony deposit in southern Xizang

通过马扎拉金锑矿床0线勘探线上电阻率联合剖面测量和音频大地电磁测深两种电法手段的对比分析,表明矿区东南部构造交汇区域的0线勘探线剖面电性特征呈南北高中间低、浅部低深部高、深部电阻率比浅部异常大的特征。结合已有地质调查成果综合分析,在该剖面上解译出可能的岩体2处,可能的北倾断裂5条,并大致估算了这些地质体的规模。矿区东南部近东西向断裂与北西向断裂、近南北向断裂交汇处为有利的找矿位置,而0线剖面上一系列近东西向北倾断裂的找矿潜力值得进一步评估和验证。

Two profiles AMT1 and AMT2 for the audio-frequency magnetotelluric sounding and three apparent resistivity joint profiles PR1,PR2 and PR3 are established in the selected favourable exploration areas. The contrast between the resistivity joint profiling and audio-frequency magnetotelluric sounding along one exploratory line of the Mazhala gold-antimony deposit in southern Xizang indicates that the electrical properties are characterized by being higher in the northern and southern parts or in the deep-seated parts,and lower in the central parts or in the shallower parts. The authors contend that the favourable exploration areas may be delineated at the junctions of the nearly EW-trending faults,NW-trending faults and nearly NS-trending faults. Much attention will also be drawn to the nearly EW-trending north-dipping faults in the low-resistivity areas in the central part of the AMT1-PR3 profile in the study area.