کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6431465 1635167 2013 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Middle Miocene vertebrates from the Amazonian Madre de Dios Subandean Zone, Perú
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات علوم زمین و سیاره ای (عمومی)
پیش نمایش صفحه اول مقاله
Middle Miocene vertebrates from the Amazonian Madre de Dios Subandean Zone, Perú
چکیده انگلیسی

A new middle Miocene vertebrate fauna from Peruvian Amazonia is described. It yields the marsupials Sipalocyon sp. (Hathliacynidae) and Marmosa (Micoureus) cf. laventica (Didelphidae), as well as an unidentified glyptodontine xenarthran and the rodents Guiomys sp. (Caviidae), “Scleromys” sp., cf. quadrangulatus-schurmanni-colombianus (Dinomyidae), an unidentified acaremyid, and cf. Microsteiromys sp. (Erethizontidae). Apatite Fission Track provides a detrital age (17.1 ± 2.4 Ma) for the locality, slightly older than its inferred biochronological age (Colloncuran-early Laventan South American Land Mammal Ages: ∼15.6-13.0 Ma). Put together, both the mammalian assemblage and lithology of the fossil-bearing level point to a mixture of tropical rainforest environment and more open habitats under a monsoonal-like tropical climate. The fully fluvial origin of the concerned sedimentary sequence suggests that the Amazonian Madre de Dios Subandean Zone was not part of the Pebas mega-wetland System by middle Miocene times. This new assemblage seems to reveal a previously undocumented “spatiotemporal transition” between the late early Miocene assemblages from high latitudes (Patagonia and Southern Chile) and the late middle Miocene faunas of low latitudes (Colombia, Perú, Venezuela, and ?Brazil).

► We describe the first early Middle Miocene mammalian locality from northern South America. ► AFTA provides a detrital age for the locality. ► The Amazonian Madre de Dios Subandean Zone was not part of the Pebas System. ► Late early Miocene times record a northward shift of forest-dependent mammals. ► Climate was seasonally contrasted in Western Amazonia ∼15 million years ago.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of South American Earth Sciences - Volume 42, March 2013, Pages 91-102
نویسندگان
, , , , , , , , , ,