| Инд. авторы: | De Grave J., Glorie S., Ryabinin A., Zhimulev F.I., Buslov M.M., Izmer A., Elburg M., Vanhaecke F., Van den haute P. |
| Заглавие: | Late Palaeozoic and Meso-Cenozoic tectonic evolution of the southern Kyrgyz Tien Shan: Constraints from multi-method thermochronology in the Trans-Alai, Turkestan-Alai segment and the southeastern Ferghana Basin |
| Библ. ссылка: | De Grave J., Glorie S., Ryabinin A., Zhimulev F.I., Buslov M.M., Izmer A., Elburg M., Vanhaecke F., Van den haute P. Late Palaeozoic and Meso-Cenozoic tectonic evolution of the southern Kyrgyz Tien Shan: Constraints from multi-method thermochronology in the Trans-Alai, Turkestan-Alai segment and the southeastern Ferghana Basin // Journal of Asian Earth Sciences. - 2012. - Vol.44. - P.149-168. - ISSN 1367-9120. - EISSN 1878-5786. |
| Внешние системы: | DOI: 10.1016/j.jseaes.2011.04.019; SCOPUS: 2-s2.0-84855344006; |
| Реферат: | eng: In this paper we present new geochronological and thermochronological data from the Turkestan-Alai segment of the southern Kyrgyz Tien Shan, the Ferghana Basin transition and the Trans-Alai Pamir foreland. In the southern and central parts of the Alai Range, towards the Alai Valley, mainly post-collisional granitoids were targeted for zircon U/Pb dating by Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS), apatite fission-track (AFT) and apatite (U-Th-Sm)/He (AHe) thermochronology. These granitoids, and their thermally metamorphosed contact aureole, yielded Middle Permian zircon crystallization ages of 284 ± 4 to 264 ± 5. Ma. AFT ages (both using the traditional external detector approach as well as using LA-ICP-MS) for these samples are constrained to the Miocene and range between 22.3 ± 1.1 and 8.4 ± 0.3. Ma, while the AHe ages are somewhat younger, between 12.5 ± 0.8 and 5.0 ± 0.3. Ma. This low-temperature thermochronological data suggests an Early Miocene onset of denudation in this area in the Tien Shan orogen, continuing through the Miocene and Pliocene. This denudation is interpreted as a response to reactivation of the mountain belt in the framework of India-Eurasia convergence, and specific to this region, of the Pamir-Tien Shan interaction. On the northern slopes of the Alai Range, at the edge of the Ferghana Basin, a Late Palaeozoic conglomerate yielded a reset Early Cretaceous AFT age of 118 ± 7. Ma, pointing to an older denudation event with respect to those identified in the southern and central parts of the Alai Range. A Mesozoic sediment sample from the same region only contains a Late Triassic age component of ∼223. Ma. Mesozoic and Cenozoic age components on the other hand are all detected in the Cenozoic sediments of the Trans-Alai Range, at the transition between the southern Alai Valley and the Pamirs, revealing several Meso-Cenozoic denudation events in the adjoining basement source rocks. The age components in these detrital apatites are ∼207. Ma, ∼75. Ma, ∼18. Ma and ∼3. Ma. © 2011 Elsevier Ltd.
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| Ключевые слова: | Tien Shan; Pamirs; Altai Mountains; uranium-lead dating; thermochronology; tectonic evolution; source rock; plate convergence; Paleozoic; Mesozoic; mass spectrometry; granitoid; geochronology; foreland basin; denudation; Cenozoic; aureole; apatite; Zircon U/Pb dating; Tien Shan; Thermochronology; Pamir; LA-ICP-MS; Apatite; Alai; |
| Издано: | 2012 |
| Физ. характеристика: | с.149-168 |