双频激电法在山区复杂条件下的应用——以福建垄源金多金属矿区为例

双频激电法可同时得到低频和高频电位差,由其计算视幅频率可抵消相同的影响因素,抑制干扰,增强异常幅值,提高观测精度。根据垄源金多金属矿区物性参数可确定受构造控制的硫化多金属矿（脉）体多以充填形式产出,具有低阻高极化反映,随着埋深的不同,视幅频率（Fs）有相应的变化,幅值一般为4%～11%,与背景视幅频率（Fs）2%～4%有明显差别。该区野外工作采用SQ-3C双频激电仪器,测网布设测线6条,其中线距100m、点距10m、、测线长度为400m。根据Fs、ρs曲线形态及Fs等值线图解释该矿区存在一条破碎带,破碎带北部呈现矿体异常特征,推断矿体（脉）走向为北西—南东向。依据该物探成果结合地质资料,布置钻探验证孔,其中8-1孔于156m见导水断裂破碎断层,8-2孔于31m见高品位金多金属矿（脉）体,验证物探解释与地质钻探吻合。

Application of Dual Frequency IP Method in Complicated Mountainous Area-A Case Study of the Longyuan Gold Polymetallic Ore Area in Jiangle, Fujian

The dual frequency IP method can get both low and high frequency voltages simultaneously.From their apparent amplitude frequency calculations can eliminate identical influencing factors,suppress noises,enhance anomaly amplitudes and improve accuracy of observations.Based on physical properties in the Longyuan gold polymetallic ore area can determine sulfide polymetallic ore bodies（veins） which occurrences are mainly infilling mineralization with low resistivity and high polarization reflex.Along with different buried depths,apparent amplitude frequencies（Fs） have corresponding variations;their amplitudes are generally 4% ～11%,significantly different from background apparent amplitude frequencies（Fs） 2%～4%.The SQ-3C dual frequency IP instrument has used in field,network layout was 6 surveying lines with line interval 100m,point interval 10m,line length 400m.Based on configuration of Fs and ρs curves and Fs isogram interpretation,a fracture zone is found in the area,its northern part has an ore body anomaly,presumed ore body（vein） strike is NW-SE.Based on the result and geological data,drilling verifying boreholes were laid out,in which,No.8-1 borehole has penetrated water conducted zone at depth 156m,No.8-2 borehole penetrated high-grade polymetallic ore body（vein） at depth 31m,thus geophysical interpretation and geological drilling data are coincided.