| Автор | Vasconcelos, P. M. |
| Дата выпуска | 1999 |
| dc.description | ▪ Abstract Recent developments in the application of K-Ar and <sup>40</sup>Ar/<sup>39</sup>Ar dating of continental weathering process demonstrate the method's suitability for dating minerals present in weathering profiles. Alunite-group sulfates and hollandite-group manganese oxides, which often precipitate through weathering reactions, were first analyzed by the K-Ar method 30 years ago. Recently these minerals were shown to be suitable to <sup>40</sup>Ar/<sup>39</sup>Ar geochronology, despite their fine-grained habits. The bulk nature of the K-Ar technique and the complex mineral assemblages in weathering profiles restrict K-Ar dating of weathering processes. The single-crystal approach possible with the <sup>40</sup>Ar/<sup>39</sup>Ar method allows the study of weathering profiles where alunite- and hollandite-group minerals occur as minor phases. Step-heating analysis possible with the <sup>40</sup>Ar/<sup>39</sup>Ar method provides information about the Ar and K retention histories, the presence of hypogene contaminants, and possible <sup>39</sup>Ar recoil during sample irradiation. Fully automated, modern <sup>40</sup>Ar/<sup>39</sup>Ar systems enable analysis of several samples, providing a comprehensive weathering database. These results are useful in the study of continental paleoclimates and the geochemical, geomorphological, and tectonic histories of an area. |
| Формат | application.pdf |
| Издатель | Annual Reviews |
| Копирайт | Annual Reviews |
| Название | K-Ar AND <sup>40</sup>Ar/<sup>39</sup>Ar GEOCHRONOLOGY OF WEATHERING PROCESSES |
| DOI | 10.1146/annurev.earth.27.1.183 |
| Print ISSN | 0084-6597 |
| Журнал | Annual Review of Earth and Planetary Sciences |
| Том | 27 |
| Первая страница | 183 |
| Последняя страница | 229 |
| Аффилиация | Vasconcelos, P. M.; Department of Earth Sciences, University of Queensland, Brisbane, Queensland 4072, Australia; e-mail: paulo@sol.earthsciences.uq.edu.au |
