气候变化领域集成服务门户(CCPortal): Surface sediment data, CaCO3 and TOC

CCPortal

DOI	https://doi.org/10.1594/PANGAEA.59873
	Surface sediment data, CaCO3 and TOC
	Mollenhauer; Gesine; Schneider; Ralph R; Müller; Peter J; Spieß; Volkhard; Wefer; Gerold
发布日期	2002-01-27
数据集类型	dataset
英文简介	Modern sedimentary total organic carbon (TOC) content as a proxy for surface water export production was mapped on the shelf and on the upper continental slope of the Benguela upwelling system using 137 core tops. Shelf maxima in TOC can be correlated with maxima in surface water productivity. On the slope, high TOC contents are observed offshore from sites of strong modern upwelling. Estimates of modern TOC mass accumulation rates (MAR) show that approximately 85% of the total is accumulating on the shelf. TOC MAR were calculated, mapped, and budgeted for the Holocene and for the Last Glacial Maximum (LGM) using 19 sediment cores from the continental slope. During the LGM, centers of deposition and production have migrated offshore with respect to their Holocene positions. TOC accumulation on the continental slope was approximately 84% higher during the LGM than during the Holocene, possibly reflecting enhanced productivity. The TOC distribution patterns and sediment echo sounding data suggest that undercurrents strongly influence the sedimentation off Namibia. Winnowing and focusing result in great lateral heterogeneity of sedimentation rates and sediment properties. Individual cores therefore do not necessarily reflect general changes in export production. These results highlight the need for detailed regional studies based on a large number of sediment cores for highly heterogeneous high-productivity areas in order to derive general statements on total fluxes.
空间范围	Median Latitude: -23.817133 * Median Longitude: 12.373333 * South-bound Latitude: -27.951667 * West-bound Longitude: 8.926667 * North-bound Latitude: -18.955000 * East-bound Longitude: 14.331667
时间范围	1993-05-27T00:00:00 - 1996-02-17T00:00:00
语种	英语
国家	国际
学科大类	气候变化
学科子类	气候变化
文献类型	数据集
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/232974
推荐引用方式 GB/T 7714	Mollenhauer,Gesine,Schneider,et al. Surface sediment data, CaCO3 and TOC.2002-01-27.https://doi.org/10.1594/PANGAEA.59873.