Geological and geochemical characteristics and deep prospecting in Lode No.1 in Jiudian gold deposit of Shandong

Lode No.1 is the largest gold-bearing quartz vein in Jiudian gold deposit.Based on the summaries on the geological and geochemical characteristics,the mineralization enrichment and the geological and geochemical indicators of the lode,the probable location of deeply-seated ore body targets are predicted.Lode No.1 is controlled by a NE trending,over 6 000 m long and averaging 3 m wide fault,and belongs to gold-bearing quartz vein in type.The gold-ore body occurs mostly in widening location of ore-controlling fractures and changing location of trendency,and the orebodies group distributes in enrichment position of lamprophyre and dioritic porphyrite.The widen portions of the faults,the coexistence of intense silicification and berecitization,the development of quartz stockwork and veinlet and the presence of lamprophyre and diorite porphyrite are the indicators for the probable sites of deep-seated ore bodies.Based on the summary of the studied resuets of more than 1000 geochemical samples,the association of As,Sb and Hg belongs to the head halo elements and the intense anomaly positions and samples reveal the deep-seated ore bodies.Based on above discussion,four ore body targets have been defined,in which two were tested in Lode No.1 by tunnel engineering.