Geological and isotopic evidence for magmatic-hydrothermal origin of the Ag–Pb–Zn deposits in the Lengshuikeng District, east-central China
| dc.contributor.author | Wang, C. | |
| dc.contributor.author | Zhang, D. | |
| dc.contributor.author | Wu, G. | |
| dc.contributor.author | Santosh, M. | |
| dc.contributor.author | Zhang, J. | |
| dc.contributor.author | Xu, Y. | |
| dc.contributor.author | Zhang, Y. | |
| dc.date.issued | 2014 | |
| dc.description.abstract | The Lengshuikeng ore district in east-central China has an ore reserve of ∼43 Mt with an average grade of 204.53 g/t Ag and 4.63% Pb + Zn. Based on contrasting geological characteristics, the mineralization in the Lengshuikeng ore district can be divided into porphyry-hosted and stratabound types. The porphyry-hosted mineralization is distributed in and around the Lengshuikeng granite porphyry and shows a distinct alteration zoning including minor chloritization and sericitization in the proximal zone; sericitization, silicification, and carbonatization in the peripheral zone; and sericitization and carbonatization in the distal zone. The stratabound mineralization occurs in volcano-sedimentary rocks at ∼100–400 m depth without obvious zoning of alterations and ore minerals. Porphyry-hosted and stratabound mineralization are both characterized by early-stage pyrite–chalcopyrite–sphalerite, middle-stage acanthite–native silver–galena–sphalerite, and late-stage pyrite–quartz–calcite. The δ³⁴S values of pyrite, sphalerite, and galena in the ores range from −3.8 to +6.9‰ with an average of +2.0‰. The C–O isotope values of siderite, calcite, and dolomite range from −7.2 to −1.5‰ with an average of −4.4‰ (V-PDB) and from +10.9 to +19.5‰ with an average of +14.8‰ (V-SMOW), respectively. Hydrogen, oxygen, and carbon isotopes indicate that the hydrothermal fluids were derived mainly from meteoric water, with addition of minor amounts of magmatic water. Geochronology employing LA–ICP–MS analyses of zircons from a quartz syenite porphyry yielded a weighted mean ²⁰⁶Pb/²³⁸U age of 136.3 ± 0.8 Ma considered as the emplacement age of the porphyry. Rb–Sr dating of sphalerite from the main ore stage yielded an age of 126.9 ± 7.1 Ma, marking the time of mineralization. The Lengshuikeng mineralization classifies as an epithermal Ag–Pb–Zn deposit. | |
| dc.description.statementofresponsibility | Changming Wang, Da Zhang, Ganguo Wu, M. Santosh, Jing Zhang, Yigan Xu, Yaoyao Zhang | |
| dc.identifier.citation | Mineralium Deposita: international journal of geology, mineralogy, and geochemistry of mineral deposits, 2014; 49(6):733-749 | |
| dc.identifier.doi | 10.1007/s00126-014-0521-8 | |
| dc.identifier.issn | 0026-4598 | |
| dc.identifier.issn | 1432-1866 | |
| dc.identifier.orcid | Santosh, M. [0000-0002-1073-8477] | |
| dc.identifier.uri | http://hdl.handle.net/2440/110103 | |
| dc.language.iso | en | |
| dc.publisher | Springer | |
| dc.rights | © Springer-Verlag Berlin Heidelberg 2014 | |
| dc.source.uri | https://doi.org/10.1007/s00126-014-0521-8 | |
| dc.subject | Stable isotope; geochemistry; porphyry; stratabound; Ag–Pb–Zn; Lengshuikeng | |
| dc.title | Geological and isotopic evidence for magmatic-hydrothermal origin of the Ag–Pb–Zn deposits in the Lengshuikeng District, east-central China | |
| dc.type | Journal article | |
| pubs.publication-status | Published |