气候变化领域集成服务门户(CCPortal): Gold remobilization associated with Mississippi Valley-type fluids: A Pb isotope perspective

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DOI	10.1130/B31901.1
	Gold remobilization associated with Mississippi Valley-type fluids: A Pb isotope perspective
	Haroldson E.L.; Beard B.L.; Satkoski A.M.; Brown P.E.; Johnson C.M.
发表日期	2018
ISSN	167606
起始页码	1583
结束页码	1595
卷号	130 期号:2021-09-10
英文摘要	Gold deposits are often observed to have complex histories with multiple mineralization and remobilization events. Lead (Pb) isotopes have been useful in identifying the source and timing of metals during the initial or "primary" mineralization in these deposits; however, the source and timing of metals associated with Pb that has more radiogenic isotope ratios as compared to the primary Pb are less definitive. Here, we used Pb isotope analyses, obtained by whole-rock, microdrilled, and in situ sampling techniques, coupled with detailed petrography to identify distinct fluid histories associated with gold mineralization in the Reef Deposit, which occurs in Penokean-age (1.8 Ga) rocks in north-central Wisconsin. Early Pb-rich minerals, encased in pyrite (as is some gold), have nonradiogenic Pb isotope ratios that match the Pb isotope composition of galena from volcanogenic massive sulfide deposits that occur locally north of the Reef Deposit. In contrast, late Pb-rich minerals, intergrown with gold, have highly radiogenic Pb isotope ratios that closely match those of galena from Paleozoic carbonate rocks in the region. A low-temperature brine fluid was found in fluid inclusion assemblages in late crosscutting carbonate veinlets. Based on these data, we infer that initial gold mineralization in the Reef Deposit was produced during the Penokean orogeny (ca. 1.8 Ga) and was subsequently overprinted by fluids similar to Mississippi Valley-type mineralization during the Permian (ca. 270 Ma). This temporal disparity between primary mineralization and remobilization, as identified by Pb isotopes, has important implications for our understanding of gold and other ore deposits. This study should prove useful to guide future Pb isotope investigations in various disciplines. © 2018 Geological Society of America.
语种	英语
来源期刊	Bulletin of the Geological Society of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/185090
作者单位	Department of Geoscience, University of Wisconsin-Madison, 1215 West Dayton Street, Madison, WI 53715, United States
推荐引用方式 GB/T 7714	Haroldson E.L.,Beard B.L.,Satkoski A.M.,et al. Gold remobilization associated with Mississippi Valley-type fluids: A Pb isotope perspective[J],2018,130(2021-09-10).
APA	Haroldson E.L.,Beard B.L.,Satkoski A.M.,Brown P.E.,&Johnson C.M..(2018).Gold remobilization associated with Mississippi Valley-type fluids: A Pb isotope perspective.Bulletin of the Geological Society of America,130(2021-09-10).
MLA	Haroldson E.L.,et al."Gold remobilization associated with Mississippi Valley-type fluids: A Pb isotope perspective".Bulletin of the Geological Society of America 130.2021-09-10(2018).