Title
The Amazonian Craton and its Influence on Past Fluvial Systems (Mesozoic-Cenozoic, Amazonia)
Date Issued
01 July 2010
Access level
metadata only access
Resource Type
book part
Author(s)
Smithsonian Tropical Research Institution
Publisher(s)
Wiley Blackwell
Abstract
The Amazonian Craton is an old geological feature of Archaean/Proterozoic age that has determined the character of fluvial systems in Amazonia throughout most of its past. This situation radically changed during the Cenozoic, when uplift of the Andes reshaped the relief and drainage patterns of northern South America. Here we review the sedimentary characteristics of Amazonian rivers and compare these with four fluvial depositional settings from the Meso-Cenozoic sedimentary record. These sedimentary units are the Alter do Chão Formation (Brazil, Late Cretaceous-Paleogene), the Petaca Formation (Bolivia, Late Oligocene to Middle Miocene), the Mariñame and Apaporis Sand Units (Colombia, Miocene), and the Iquitos White Sand Unit (Peru, Late Miocene-Pliocene). This review illustrates that the river systems born on the craton share features such as sediment texture and composition, depositional environments and transport directions. Evidence for the diminished role of cratonic fluvial systems and the onset of Neogene Andean uplift can be identified in the sedimentary record by changes in sediment provenance and transport directions. Although the Andean uplift and related processes discontinued the major Amazonian-born fluvial systems it also created new topographic features such as the Iquitos and Fitzcarrald Arches. These newly formed reliefs triggered a new generation of rivers, some of which are presently known as biodiversity hotspots.
Start page
103
End page
122
Language
English
OCDE Knowledge area
Geología
Subjects
Scopus EID
2-s2.0-84987688294
Resource of which it is part
Amazonia, Landscape and Species Evolution: A Look into the Past
ISBN of the container
9781444306408
Sources of information:
Directorio de Producción Científica
Scopus