Ore genesis of the Zhuxi supergiant W-Cu skarn polymetallic deposit, South China: Evidence from scheelite geochemistry

Sun, Keke1; Chen, Bin2; Deng, Jun1

2019-04

10.1016/j.oregeorev.2019.02.017

ORE GEOLOGY REVIEWS   影响因子和分区

0169-1368

1872-7360

Scheelite is the main ore mineral in skam-type tungsten deposits, which can be used to track the ore-forming processes and sources. The Zhuxi W-Cu deposit (3.44 Mt WO3 at 0.54% and 0.10 Mt Cu at 0.57%), located in the northern part of the Jiangnan orogen, is one of the largest tungsten deposits in the world. Skarn and orebodies occur mainly within the contact zone between the Mesozoic highly fractionated intrusions and Carboniferous carbonate sediments (Huanglong and Chuanshan formations). Our data reveal that the REEs of scheelite are mainly controlled by the substitution mechanism 3Ca(2+) = 2REE(3+) + square Ca. Scheelites from the Zhuxi deposit show negative Eu anomalies in the prograde skarn stage, but positive Eu anomalies in the retrograde skarn stage in the chondrite-normalized REE patterns. Variation of Eu anomalies recorded the ore-forming processes. The negative Eu anomalies were inherited from the Mesozoic granites and the positive ones formed under more reduced redox conditions. The decrease of Mo concentrations, along with increase of delta Eu and delta Ce of scheelite from prograde to retrograde skarn stage, support a temporal decrease in oxygen fugacity of the mineralization fluids. The scheelites from the Zhuxi deposit are characterized by low epsilon(Nd)(t) values (10.1 to 7.0) and high initial Sr-87/Sr-86 ratios (0.71231-0.72371), which are different from the scheelites hosted in vein-type Au-W deposits contributed mainly by mantle. The Nd-Sr isotopes of scheelites are consistent with the results of the three Mesozoic granites, indicating their genetic relationship. However, the scheelites show variable Nb/Ta compositions, which straddle between the values of Mesozoic granites and the country rock of Shuangqiaoshan Group meta-sedimentary rocks, indicating the Shuangqiaoshan Group also has contributed to mineralization. This is different from a commonly accepted model that the ore-forming fluids and metals were exsolved exclusively from the granite plutons.

Scheelite Trace element REE Sr-Nd isotopes Zhuxi

SCI ; EI

英语

通讯

Open Research Project from the State Key Laboratory of Geological Processes and Mineral Resouces, China University of Geosciences[GPMR201822]

Geology ; Mineralogy ; Mining & Mineral Processing

Geology ; Mineralogy ; Mining & Mineral Processing

WOS:000470194300002

ELSEVIER SCIENCE BV

20190806537689

Binary alloys ; Copper deposits ; Deposits ; Europium ; Gold alloys ; Gold deposits ; Granite ; Isotopes ; Mineralogy ; Neodymium alloys ; Sedimentary rocks ; Strontium alloys ; Trace elements ; Tungstate minerals ; Tungsten deposits

Mineralogy:482 ; Minerals:482.2 ; Heavy Metal Mines:504.3 ; Precious Metals:547.1 ; Rare Earth Metals:547.2 ; Alkaline Earth Metals:549.2

GEOSCIENCES

Web of Science

1.China Univ Geosci, State Key Lab Geol Proc & Mineral Resources, Beijing 100083, Peoples R China
2.Southern Univ Sci & Technol, Dept Earth & Space Sci, Shenzhen 518055, Peoples R China

Sun, Keke,Chen, Bin,Deng, Jun. Ore genesis of the Zhuxi supergiant W-Cu skarn polymetallic deposit, South China: Evidence from scheelite geochemistry[J]. ORE GEOLOGY REVIEWS,2019,107:14-29.

Sun, Keke,Chen, Bin,&Deng, Jun.(2019).Ore genesis of the Zhuxi supergiant W-Cu skarn polymetallic deposit, South China: Evidence from scheelite geochemistry.ORE GEOLOGY REVIEWS,107,14-29.

Sun, Keke,et al."Ore genesis of the Zhuxi supergiant W-Cu skarn polymetallic deposit, South China: Evidence from scheelite geochemistry".ORE GEOLOGY REVIEWS 107(2019):14-29.