Sea level induced variations in clay mineral composition in the southwestern South China Sea over the past 17,000 yr
Sea level induced variations in clay mineral composition in the southwestern South China Sea over the past 17,000 yr
复制标题
DOI：
10.1016/j.margeo.2008.01.005
复制
发表时间：
2008-05
期刊：
影响因子：
2.9
通讯作者：
S. Steinke;T. Hanebuth;C. Vogt;K. Stattegger
中科院分区：
文献类型：
--
作者：
S. Steinke;T. Hanebuth;C. Vogt;K. Stattegger
巽他陆架边缘和陆坡沉积物岩心粘土矿物组成的变化反映了近17，000年来沉积物来源的变化以及沃茨中粘土矿物分配过程的影响。我们确定冰消期海平面上升的主要因素驱动这些变化。在晚冰期，高岭石的高值被解释为反映了较高的贡献，从土壤中形成的暴露的巽他大陆架和印度尼西亚南部群岛的粘土。此时，岩芯地点位于露出的大陆架（“Sundaland”）上的Sunda大陆架古排水系统口附近。冰川消退期间，海岸线逐渐向陆地移动，这些巨大的排水系统崩溃，导致富含高岭石的南部来源的影响力下降。当海岸线在全新世中期后退到今天的位置时，南部来源的主导地位被富含伊利石的来源（例如婆罗洲）的强大影响所取代。海平面变化对粘土矿物分布模式的压倒性控制排除了在这种高度动态的沉积环境中气候/季风变化方面对粘土矿物数据进行明确的气候解释。
Variations in clay mineral composition of sediment cores from the margin and continental slope of the Sunda Shelf (southern South China Sea, SE Asia) covering the past 17,000 yr reflect changing influences of sediment sources together with clay mineral partitioning processes in shallow waters. We identify the deglacial sea level rise as the principal factor driving these changes. During the late glacial, high values of kaolinite are interpreted to reflect a higher contribution of clays from soils that have formed on the exposed Sunda Shelf and in the southern archipelagos of Indonesia. At this time core sites were located in close proximity to the mouths of the Sunda Shelf palaeo-drainage systems on the emerged shelf (“Sundaland”). The progressive landward displacement of the coastline and breakdown of these vast drainage systems during deglaciation led to a decrease in influence of the kaolinite-rich southern sources. When the coastline had retreated closely to its present-day position in mid-Holocene times, the former dominance of southern sources was replaced by a stronger influence of illite-rich sources (e.g. Borneo). The overriding control of sea level changes on the clay mineral distribution patterns precludes a definite climatic interpretation of clay mineral data in terms of climatic/monsoonal changes in such highly dynamic sedimentary environment.