Abstract
Between the western and eastern Andean cordilleras in Peru and Bolivia, there are three main lacustrine basins: Lake Titicaca, Lake Poopó, and the group of Coipasa-Uyuni. For the past few millennia, highly variable environmental conditions have been recorded in their sediments. Today a latitudinal meteorological gradient influences the lakes' status, leading to specific deposits and ostracod communities. Lake Titicaca in the north is oligohaline, whereas Lake Poopó further south is polyhaline. In the south, the Coipasa-Uyuni depression is characterized by a 12,000-km 2 surficial salt crust. During the Late Pleistocene (ca. 40,000 to 25,000 yr B.P.), the water depth and salinity in paleolake Poopó fluctuated widely and paleolake Titicaca was slightly larger than at present. Sedimentation was mostly biocarbonate in the shallower areas and it was detrital-organic in the deepest zones. During the Holocene, a dry period transformed Lake Poopó into a "salar" with evaporite precipitation. Lake Titicaca registered a large decline in water level (8100-3600 yr B.P.) initially inducing gypsum precipitation followed by short influxes of water, with an ostracod faunal composition similar to that of the modern brines of Lake Poopó. Lake Titicacas' present condition only appeared between 2200 and 1500 yr B.P.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.