Comparison of Guilin and Nevada Carlin-Type Gold Deposits in China and Their Role in Indicating Prospecting
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The article summarizes and contrasts the Carlin-type gold deposits in Nevada and Guizhou in terms of regional geology and deposit geology. The results show that there are many similarities and differences between the gold mines in the two places. The main similarities include: the tectonic background evolution of the two places has experienced early extension rifts, deposited a set of passive continental margin marine sedimentary strata, subsequent orogenic compression and late extension; the ore body is mainly controlled by iron-rich strata and structures ; Alterations related to gold mineralization are sulfidation, decarbonation, silicification, and mudification; gold is mainly present in arsenic-containing pyrite as invisible gold; late realgar, female yellow, antimonite Minerals such as calcite and calcite fill the open space in veins. Important differences are reflected in the regional distribution control factors of ore deposits; no magmatic rocks are found in the vast majority of Guizhou gold deposits; dolomite petrochemicals unique to Guizhou gold deposits; and relatively weak decarbonation, silicification (like jasper), and Morphology; morphology and trace element content of golden iron ore deposits; some Guizhou gold deposits contain ore-forming period-late ore-forming poisonous sand; Guizhou has a large number of late quartz- (calcite) veins; Guizhou ore-forming fluids are more enriched with CO 2 And has higher temperature, pressure and pH. The identification of similarity and difference plays an important role in the prospecting and exploration of Carlin-type gold deposits (especially the Carlin-type gold deposits in Guizhou). Slope facies formation is the best ore-forming layer for Carlin-type gold deposits. In the exploration of Carlin-type gold deposits, more attention should be paid to slope-phase formations, especially iron-rich slope-phase formations. Recently, in the regional unconformity surface (also known as "tectonic alteration", or SBT) in the basalt distribution area of Guizhou, major breakthroughs have been made in gold prospecting. Lithology. In Guizhou, identifying the SBT and the structural high point of the upper part of the SBT between the Maokou Formation and the Longtan Formation (or Emeishan Basalt) is very important for regional gold prospecting in the platform facies area. Identifying the same Devonian carbonate platform as the same sedimentary fault is very important for investigating the regional distribution of the deposit (especially the regional distribution of gold deposits in the basin facies). A large number of jasperite-like outcrops or quartz-calcite veins indicate that a large number of water-rock reactions occurred in this area, indicating that large-scale mineralization may occur around it. The late mineralization minerals such as antimony, realgar and female yellow are mostly filled with veins in the open space around the ore body, which has a wider range of distribution than the ore body and has a good indication of the ore body.
Geology; Guilin Carlin-type gold deposit; Nevada Carlin-type gold deposit; Comparative study; Carlin-type gold prospecting
Comparison of Guilin and Nevada Carlin-Type Gold Deposits in China and Their Role in Indicating Prospecting.