¹⁰Be dating of river terraces of Santo Domingo river, on Southeastern flank of the M茅rida Andes, Venezuela: Tectonic and climatic implications

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• 作者：Oswaldo Guzm谩n ; Riccardo Vassallo ; Franck Audemard ; Jean-Louis Mugnier ; Javier Oropeza ; Santiago Yepez ; Julien Carcaillet ; Miguel Alvarado ; Eduardo Carrillo
• 关键词：Venezuela ; Mé ; rida Andes ; River terraces ; Climatic control ; Uplift rate ; In situ produced 10Be
• 刊名：Journal of South American Earth Sciences
• 出版年：December, 2013
• 年：2013
• 卷：48
• 期：Complete
• 页码：85-96
• 全文大小：4243 K

文摘

In this study, we discuss the first cosmogenic ¹⁰Be dating of river terraces located in the lower reaches of the Santo Domingo river (Southeastern flank of the M茅rida Andes, Western Venezuela). The geomorphic observations and dating allowed the restoration of the temporal evolution of incision rate, which was analysed in terms of tectonic, climatic and geomorphic processes. The long-term incision rate in the area has been constantly around 1.1 mm/a over the last 70 ka. Taking into account the geologic and geomorphologic setting, this value can be converted into the Late Pleistocene uplift rate of the Southeastern flank of the M茅rida Andes. Our results show that the process of terraces formation in the lower reaches of the Santo Domingo river occurred at a higher frequency (10³-10⁴ years) than a glacial/interglacial cycle (10⁴-10⁵聽years). According to the global and local climate curve, these terraces were abandoned during warm to cold transitions.