Premium
Properties and Evolution of Ore‐forming Fluid in Continental Sandstone‐type Copper Deposit: a Case Study from Liuju and Haojiahe Deposits in Chuxiong Redbed basin in Yunnan Province, China
Author(s) -
WU Haizhi,
HAN Runsheng,
WU Peng
Publication year - 2014
Publication title -
acta geologica sinica ‐ english edition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.444
H-Index - 61
eISSN - 1755-6724
pISSN - 1000-9515
DOI - 10.1111/1755-6724.12379_56
Subject(s) - geological survey , china , geology , mineral resource classification , mining engineering , structural basin , chinese academy of sciences , geochemistry , archaeology , geography , geomorphology , paleontology
Liuju and Haojiahe copper deposits, which located in the Chuxiong Cretaceous red bed basin, Yunnan, China, are two typical continental sandstone-type deposits and attributable to the sedimentary-diagenesis-reworked type of deposits. Orebodies of these two deposits, hosted in a set of mediumand fine-grained feldspar-quartz sandstone of Upper Cretaceous, are located in the interface between purple bed and grey bed, sandwiched between two purple silty mudstones. Besides, there coexist a horizontal metallic mineral zonation in this transitional zone from purple sandstone to grey sandstone: hematite, chalcocite,bornite,chalcopyrite and pyrite. Two different types of ore occurred in both two deposits: disseminated or laminated ores and banded or veined ores. The ores with the former fabric were mainly located in the stratiform or stratoid orebodies within mediumand fine-grained sandstone in the flanks and core of folds(Fig. 1A). While, the latter fabric of ores were located in or nearby the the fractures or joints, and the grade of which is much higher than the former. The highest grade of veined ores at Haojiahe deposit even exceed 20%(Fig. 1B). The two types of ore at Liuju and Haojiahe deposits respectively represent two typical mineralization process of sandstone-type copper deposits in this area, that was diagenesis period and tectonic-reworked period(Ran et al,1998).