Stepwise prospecting method for deep-seated deposits: Take deep prospecting of ore concentration area of gold in Jiaodong Peninsula, China as an example

This paper is the result of mineral exploration engineering.

Objective Jiaodong Peninsula is the first region to carry out deep-seated prospecting and made significant prospecting achievements in China. Stepwise prospecting method has played an important role in the deep-seated exploration. The study of deep-seated prospecting methods will be conducive to promoting the implementation of the prospecting strategy of "prospecting deep-seated deposits" in East China.

Methods In this paper, based on the deep-seated gold deposits prospecting in Jiaodong, we studied the metallogenic model of deep gold deposits, and analyzed the role and effect of controlled source audio frequency magnetotelluric sounding (CSAMT), spectral excited electric sounding (SIP), magnetotelluric sounding (MT) and reflection seismic methods in deep gold deposits prospecting.

Results Deep orebodies generally occur in the gently dipping parts of alternate change of steep-dipping to gentle-dipping of the ore-controlling fault, forming a step metallogenetic model. This metallogenetic model is a comprehensive reflection of tectonic activities and physicochemical conditions of mineralization. The technical process of the stepwise prospecting method is outlined below. First, through high precision geophysical detection in land surface, deep characteristics of ore-controlling fault are found out. Then, according to the step metallogenic model, the location and scale of the deep-seated gold orebodies are predicted.

Conclusions The step metallogenic model provides a technical premise and key exploration target for the deep-seated gold deposits prospecting. CSAMT, SIP, MT and reflection seismic methods can detect the deep characteristics of ore-controlling faults. The combination of multiple geophysical methods is an effective technical means of the stepwise prospecting method.