Thoughts on the Jiaodong Gold Province of China: Towards a Tectonic Model

Abstract

The Jiaodong gold province is situated in the eastern Sino‐Korean Platform within the so‐called Jiaoliao Uplift. The basement rocks are Archaean and Proterozoic metamorphic rocks. Mesozoic sedimentary and volcanic cover occur within extensional basins. Intrusive rocks are dominated by Mesozoic granitoid, with intermediate‐acid and basic dyke swarms. The structures form an E‐W‐trending anticlinorium in the basement complex, and large‐scale NE‐SW‐ and NNE‐SSW‐trending fault zones of Mesozoic age. The gold mineralization is associated with the Mesozoic faults and related secondary fractures in the granites or granite‐basement contacts. The mineralization types are quartz‐vein type and wall‐rock alteration type. Wall‐rock alteration is very well developed around the ore zones. Alteration minerals include quartz, sericite (and fuchsite), pyrite, calcite, chlorite, hematite, rutile and graphite. The ore assemblage is uniform in all deposits, including pyrite, chalcopyrite, galena, sphalerite, arsenopyrite, pyrrhotite, gold, electrum, hessite, petzite, magnetite, molybdenite, tetrahedrite and wolframite. Mesozoic collision and subduction between the South China and North China continental blocks contributed to formation of the Mesozoic granitoid intrusions. The granitic magma is considered to be derived from partial melting of the crust through underplating processes. Gold was remobilised from basement rocks and deposited in fracture zones by the high‐temperature fluids associated with these processes.

Composition Typomorphic Characteristics of Pyrite in Various Genetic Type Gold Deposits

“…The iron disulphide pyrite is the most common and important gold-bearing mineral in gold deposits [1][2][3], which occurs 85% as a major gold-bearing mineral in gold depositis [4]. Numerous investigations have been done in typomorphism characteristics of pyrite, such as composition, structure, physical properties, isotope, and these investigations have acquired plenty of genesis information in gold deposits.…”

“…Numerous investigations have been done in typomorphism characteristics of pyrite, such as composition, structure, physical properties, isotope, and these investigations have acquired plenty of genesis information in gold deposits. Among these pyrite typomorphisms, composition typomorphism is one of the most basic and significant typomorphisms [2,3]. The relation between composition typomorphism and genesis in one deposit has always been drawing a lot of interests around the world [3,5].…”

“…The S/Fe ratio in pyrite is generally very close to 2, suggesting that stoichiometric variability is small in this mineral [6]. The number of trace elements in pyrite is large, above 50 [2]. Arehart et al (1993a) [7] studied the gold and arsenic in iron sulfides from sediment-hosted disseminated gold deposits.…”