Contourite depositional system on the Argentine Slope: An exceptional record of the influence of Antarctic water masses
Contourite depositional system on the Argentine Slope: An exceptional record of the influence of Antarctic water masses
复制标题
DOI：
10.1130/g25578a.1
复制
发表时间：
2009-06-01
期刊：
影响因子：
5.8
通讯作者：
Rebesco, Michele
中科院分区：
文献类型：
--
作者：
Javier Hernandez-Molina, F.;Paterlini, Marcelo;Rebesco, Michele
本文首次描述了阿根廷大陆边缘南部陆坡上一个重要的等深岩沉积体系。该系统包含侵蚀和沉积特征，这些特征是由几个因素造成的，包括舌状源水团的地形强化、这些水团速度的系统性向北减小、下坡沉积过程的向北增加以及局部构造影响。这个系统是一个特殊的例子，CDS开始在始新世-渐新世边界的时间，可能与德雷克通道的开放同时代的发展。然而，一个新的边缘形态，其特点是一个复杂的梯田斜坡缺乏任何大陆隆起，发展后，一个重大的古海洋变化中晚中新世。我们推测，这种变化是北大西洋深层水环流向南半球延伸和阿根廷海盆南极底层水环流加深的结果。
A significant contourite depositional system (CDS) on the continental slope of the southern Argentine margin is described here for the first time. This system contains both erosive and depositional features that have resulted from several factors, including topographic intensification of the Antarctic-sourced water masses, the systematic northward decrease in speed of these water masses, a northward increase of downslope sedimentary processes, and local tectonic influences. This system is an exceptional example of a CDS that started to develop at the time of the Eocene-Oligocene boundary, potentially coeval with the opening of the Drake Passage. However, a new margin morphology, characterized by a complex terraced slope lacking any continental rise, developed after a major paleoceanographic change in the middle to late Miocene. We infer that this change resulted from the extension of North Atlantic Deep Water circulation into the Southern Hemisphere and the deepening of Antarctic Bottom Water circulation in the Argentine Basin.