U-Th-He dating of native gold: First results,problems, and outlooks |
| |
Authors: | O V Yakubovich Yu A Shukolyukov A B Kotov M Brauns A V Samsonov A N Komarov S Z Yakovleva E B Sal’nikova B M Gorokhovskii |
| |
Institution: | 1. Institute of Precambrian Geology and Geochronology, Russian Academy of Sciences, nab. Makarova 2, St. Petersburg, 199034, Russia 2. Faculty of Geology, St. Petersburg State University, Universitetskaya nab. 7-9, St. Petersburg, 194034, Russia 3. Curt-Engelhorn-Zentrum Arch?ometrie, D63, 68159, Mannheim, Germany 4. Institute of Geology of Ore Deposits, Petrography, Mineralogy, and Geochemistry (IGEM), Russian Academy of Sciences, Staromonetnyi per. 35, Moscow, 119017, Russia
|
| |
Abstract: | In this paper, we consider the application of the U-Th-He method of isotope geochronology for native gold dating. It was shown that inclusions of uranium- and thorium-bearing minerals, including rare earth element phosphates, are one of the main form of uranium and thorium occurrence and, consequently, the main source of radiogenic helium in native gold. Since these inclusions are submicrometer-sized, the radiogenic helium formed in them is not accumulated but implanted in the structure of native gold, which suggests its good preservation over billions of years. This suggestion was experimentally supported by the investigation of the kinetics of radiogenic helium release from native gold. The first results of the U-Th-He dating of native gold from the Pedrolampi (central Karelia) and Witwatersrand (South Africa) deposits are in adequate agreement with available independent geochronological data. This allows us to consider native gold as a U-Th-He mineral geochronometer for the direct dating of ore-forming processes. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|