Relative roles of formation and preservation on gold endowment along the Sanshandao gold belt in the Jiaodong gold province, China: importance for province- to district-scale gold exploration

The 13-km-long Sanshandao gold belt along the NNE-trending Sanshandao Fault has highly variable orogenic gold endowment along-strike. New thermochronological data from the small Cangshang gold deposit demonstrate similar degrees of uplift and exhumation rates as for larger deposits, negating selective preservation as the prime gold-endowment factor. The Haiyu, Sanshandao, Xiling, and Cangshang deposits, of variable gold endowment, lie adjacent to NE-ENE-trending jogs, similar to those at Jiaojia and Linglong, so these structures cannot be the prime control on gold mineralization. Ore-zones show a broad gentle northeast plunge, with the southwestern Cangshang and Xinli deposits being closest to the ground surface, and the northeastern Haiyu deposit being the deepest. Thus, preferential erosion of the shallower southwestern orebodies could be a factor affecting endowment. Another variable is the depth of drilling. At Haiyu-Sanshandao, gold mineralization is better developed on more gently dipping fault segments, consistent with a thrust component of oblique slip along them. Relative to the northeastern deposits, the Cangshang and Xinli deposits are located in areas where relatively shallow drilling has intersected ore zones on steeply dipping fault segments, indicating the potential for deeper drilling to intersect gold ore along deeper more gently dipping segments. Heterogeneous gold endowment is thus largely a formational factor related to the plunge of orebodies combined with the variable depth of drilling along the Sanshandao Fault. Over the entire Jiaodong gold province, there are equivalent-age mesozonal to epizonal orebodies, implicating their preservation at different crustal levels and thus increasing the province-scale gold endowment potential and probability of further exploration discoveries.