Dating of paleolakes in the central altiplano of bolivia

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Lake Ballivián is an ancient lake in the Altiplano of South America and is named after the Bolivian scholar Don Manuel Vicente Ballivian.It is part of a series of lakes which developed in the Titicaca basin along with Lake Mataro and Lake Cabana, reaching an altitude of 3,860 metres (12,660 ft).Such evidence from late Quaternary palaeolakes, in fact, ranks among of the most complete and accessible sources of palaeoclimatic proxy data currently available for the late Pleistocene and Holocene.The chronology, sedimentary history, and paleoecology of the Tarija Basin (Bolivia), one of the richest Pleistocene mammalian sites in South America, are revised here based on a multidisciplinary study, including stratigraphy, sedimentology, geomorphology, paleontology, isotope geochemistry, and C dates encompassing all the fossil-bearing sequences previously studied in the Tarija Basin.The tropical Andes of Peru and Bolivia are important for preserving geomorphic evidence of multiple glaciations, allowing for refinements of chronology to aid in understanding climate dynamics at a key location between hemispheres. This review focuses on the deglaciation from Late-Pleistocene maximum positions near the global Last Glacial Maximum (LGM). The Altiplano in South America is a high plateau between the Eastern Cordillera and the Western Cordillera with an average altitude of 3,800 metres (12,500 ft) and a surface area of 200,000 square kilometres (77,000 sq mi).A number of evaporation landforms can be found in the Altiplano, including Salar de Uyuni and Salar de Coipasa. it was formerly occupied by large lakes that grew and dried out in many phases.

Special consideration is given to document paleoglacier valley localities with topographic information given the strong vertical mass balance sensitivity of tropical glaciers.

Specific valley localities show variable and heterogeneous sequences ages and extensions of paleoglaciers, but conform to a generally cogent regional sequence revealed by more continuous lake sedimentary records. Last Glacial Maximum and deglaciation of Ampato volcanic complex, Southern Peru.

There are clear distributions of stratigraphically older and younger moraine ages that we group and discuss chronologically.

62 and 20 ka BP, respectively) are also documented at the base and at the very top of the Tarija–Padcaya succession, respectively, indicating that the Bolivian Altiplano was not dry but sustained an ice cap during the Last Glacial Maximum.

The results of this multidisciplinary study enable us to redefine the chronological limits of the Tarija sequence and of its faunal assemblage and to shift this paleontological, paleoclimatological, and paleoecological framework to the time interval from MIS 4 to MIS 2.

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