Recent deep-water sedimentation, trace metal and radioisotope geochemistry across the Southern Ocean and northern Weddell Sea, antarctica
Recent deep-water sedimentation, trace metal and radioisotope geochemistry across the Southern Ocean and northern Weddell Sea, antarctica
复制标题
DOI：
10.1016/j.dsr2.2007.07.007
复制
发表时间：
2007-01-01
影响因子：
3
通讯作者：
Carpenter, Lawrence W.
中科院分区：
文献类型：
--
作者：
Howe, John A.;Wilson, Charles R.;Carpenter, Lawrence W.
对南极洲南大洋和威德尔海北部的 12 个采样站的各种深水沉积环境进行了检查，以便为 ANDEEP（南极底栖深海生物多样性：殖民历史和近期群落模式）的底栖生物多样性研究提供沉积背景。在这里，我们提供了一个多样化的数据集，包括海底剖面、海底照片、沉积物剖面图像以及箱式和多岩心样本，以便研究该地区最近的沉积环境。使用质地、结构、痕量金属（Mn、Fe、U、Mo、Ba 和 Pb）、稳定（Pb-206/Pb-207）和放射性核素（过量 Pb-210）同位素对沉积物进行了研究。厄加勒斯盆地的沉积物被解释为硅质远山岩，是地表生产力增强的产物。东威德尔大陆隆起的特点是沉积环境多样，包括半远洋沉积、浊积沉积和等高线沉积。相比之下，威德尔深渊平原北部以半白岩为主，并伴有细粒浊积岩。鲍威尔盆地中部的一个采样站含有半白岩和细粒浊积岩。布兰斯菲尔德海峡中部的岩心发现了带有粉砂浊积岩的半白岩。海底照片显示，海底主要由卷毛类多毛类动物形成的生物泥球组成。痕量金属、Pb 同位素和过量 Pb-210 数据均表明布兰斯菲尔德海峡中部是一个生产力增强的区域，质量积累率为 0.073g/cm(2)。别林斯高晋海的两个站发现了半白岩和浊积岩。锰、铁和钼数据表明沉积物中有机物的降解导致氧化还原循环。 (c) 2007 Elsevier Ltd. 保留所有权利。
A wide variety of deep-water depositional environments were examined across 12 sampling stations in the Southern Ocean and northern Weddell Sea, Antarctica in order to provide a depositional context for the benthic biodiversity studies of ANDEEP (Antarctic Benthic Deep-Sea Biodiversity: colonisation history and recent community patterns). Here we present a diverse dataset comprising sub-bottom profiles, seabed photographs, sediment profile images, and box and multicore samples in order to investigate the recent depositional environments across the region. The sediments were investigated using texture, structure, trace metal (Mn, Fe, U, Mo, Ba, and Pb), stable (Pb-206/Pb-207) and radionuclide (excess Pb-210) isotopes. The sediments of the Agulhas Basin are interpreted as siliceous pelagites, the product of enhanced surface productivity. The eastern Weddell continental rise is characterised by diverse depositional environments with hemipelagic, turbiditic and contouritic sedimentation. In contrast, the northern Weddell Abyssal Plain is dominated by hemipelagites with fine-grained turbidites. A single sampling station from the central Powell Basin contained hemipelagites and a fine-grained turbidite. A core from the central Bransfield Strait recovered hemipelagites with a silt turbidite. The seabed photographs display a seabed dominated by biogenic mud balls formed by cirratulid polychaetes. Trace metal, Pb-isotope, and excess Pb-210 data all reveal the central Bransfield Strait to be a region of enhanced productivity with a mass accumulation rate of 0.073g/cm(2). Two stations in the Bellingshausen Sea recovered hemipelagites and turbidites. Mn, Fe and Mo data suggest a degradation of organic matter in the sediments leading to redox cycling. (c) 2007 Elsevier Ltd. All rights reserved.