期刊
QUATERNARY RESEARCH
卷 81, 期 2, 页码 339-354出版社
CAMBRIDGE UNIV PRESS
DOI: 10.1016/j.yqres.2014.01.003
关键词
Marine depocenters; Sedimentary pathways; Current control; Source to sink; Southeastern South America; Southwest Atlantic; Water masses; Late Quaternary
资金
- DFG-Research Center/Cluster of Excellence
- Heisenberg fellowship [HA4217/4-1]
- FAPESP [2010/09983-9, 2012/17517-3]
- Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) [10/09983-9] Funding Source: FAPESP
The continental margin off the La Plata Estuary (SE South America) is characterized by high fluvial sediment supply and strong ocean currents. High-resolution sediment-acoustic data combined with sedimentary facies analysis, AMS-C-14 ages, and neodymium isotopic data allowed us to reconstruct late Quaternary sedimentary dynamics in relation to the two major sediment sources, the La Plata Estuary and the Argentine margin. Sediments from these two provinces show completely different dispersal patterns. We show that the northward-trending La Plata paleo-valley was the sole transit path for the huge volumes of fluvial material during lower sea levels. In contrast, material from the Argentine margin sector was transported northwards by the strong current system. Despite the large sediment volumes supplied by both sources, wide parts of the shelf were characterized by either persistent non-deposition or local short-term depocenter formation. The location and formation history of these depocenters were primarily controlled by the interplay of sea level with current strength and local morphology. The high sediment supply was of secondary importance to the stratigraphic construction, though locally resulting in high sedimentation rates. Thus, the shelf system off the La Plata Estuary can be considered as a hydrodynamic-controlled end-member. (c) 2014 University of Washington. Published by Elsevier Inc. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据