Formation Types and Comparative Analysis of Jinshan and Maquan Gold Deposits in Gansu

Jinshan and Maquan are two medium-sized gold deposits of a branch of the acute angle,which were formed by expansion of the western part of Lixian-Baiyun-Shanyang fault.We carried out the comparative analysis of the regional geological data and characteristics,and formation causes.Middle Devonian and Carboniferous,strata in the gold-bearing show that the gold sources of Maquan should come from the shallow strata;the analysis of the samples of quartz δ¹⁸O shows that the main physical component of the ore is ore-forming solution water,we get that the hydrothennal water was formed by a small amount of ore forming solution percolated through a large number of meteoric water.The characteristics of sulfur isotopic and REE patterns show deep-derived sulfur,but the rare earth elements also from the strata Through physical and chinical conditions of mineralization,them ineralization conditions shouldmeet low-temperatureweak salinity,weak acidity and weak reducing conditions Zhongchuan rock body is a heat source body of the formation of the deposit.Infection-type deposits should be fine (Carlin-type) gold deposits.The geological survey in the future should consider overall (in particular,the combination of the two deposits),so thatwe can realize the expansion of the existing deposits.