A ‘snapshot’ of the evolution of the Uruguay River (Del Plata Basin): the Salto depositional sequence (Pleistocene,Uruguay, South America) |
| |
| Institution: | 1. Department of Geography, Durham University, South Road, Durham DH1 3LE, UK;2. Institute of Archaeology & Antiquity, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK;3. School of Civil Engineering and Geosciences, Newcastle University, Newcastle-upon-Tyne NE1 7RU, UK;1. Department of History, Federal University of Santa Catarina, Florianopolis, Santa Catarina, Brazil;2. Department of History, Federal University of Rio Grande do Sul, Brazil;3. Institute of Archaeology, University College London, UK;1. Sección Genética Evolutiva, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay;2. Departamento de Parasitología y Medicina, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay;3. Laboratorio de Citogenética Alberto Tellería Cáceres, Universidad Nacional Mayor de San Marcos, Lima, Peru;4. INTERTRYP (Interactions hôtes-vecteurs-parasites dans les infections par trypanosomatidae), Institut de Recherche pour le Développement (IRD), Montpellier, France;1. Sección Virología, Facultad de Ciencias, Universidad de la República, Iguá 4225, Montevideo 11400, Uruguay;2. División Sanidad Animal, Ministerio de Ganadería, Agricultura y Pesca, Constituyente 1476, Montevideo 11200, Uruguay;1. Sección Virología, Facultad de Ciencias, Universidad de la República, Iguá 4225, 11400 Montevideo, Uruguay;2. British Hospital, Av. Italia 2420, 11600 Montevideo, Uruguay;1. Sección Virología, Facultad de Ciencias, Universidad de la República, Iguá 4225, Montevideo 11400, Uruguay;2. División Sanidad Animal, Ministerio de Ganadería, Agricultura y Pesca, Constituyente 1476, Montevideo 11200, Uruguay |
| |
| Abstract: | This paper provides sedimentological details of the Salto depositional sequence of western Uruguay, which includes the Salto and the Bellaco Formations. These units are interpreted as evidence, in the Uruguayan landscape, of a Pleistocene forebear of the Uruguay River. The Salto depositional sequence, encompasses two depositional cycles: (a) the lower cycle, represented only by the Salto Formation, with conglomeratic sandstones and sandstones intercalated with pelites and fine sandstones; and (b) the upper cycle, represented by the Salto Formation and the Bellaco Formation, characterized by conglomerates and conglomeratic sandstones with horizontal stratification, discontinuous silicified sandy levels and gypsum–clay bodies. The Salto sequence is characterized by braided river deposits, genetically associated with lacustrine or palustrine and possible aeolian sediments. Cyclic alternations of channelized tractive currents and interchannel contexts are indicated. A possible Pleistocene age for the Salto Formation is discussed, in the light of new and preliminary information (thermoluminescence ages) from the lower cycle. There are several lines of evidence indicating semi-arid conditions during the ‘Salto event’. Comments on regional correlation are provided, as well as the effects of neotectonic processes. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
