Grain-size analysis of the Late Pleistocene sediments in the Corinth Rift: insights into strait-influenced hydrodynamics and provenance of an active rift basin
Grain-size analysis of the Late Pleistocene sediments in the Corinth Rift: insights into strait-influenced hydrodynamics and provenance of an active rift basin
复制标题
科林斯裂谷晚更新世沉积物的粒度分析：深入了解海峡影响的流体动力学和活动裂谷盆地的起源
DOI：
10.1144/sp523-2022-166
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Kang W
中科院分区：
文献类型：
--
作者：
Kang W
通过对科林斯裂谷M0079A钻孔沉积物的粒度分析，探讨了晚更新世科林斯裂谷的水动力条件和物源。对沉积环境敏感的粒度种群具有频数分布、粒度标准差和概率累积曲线等特征。我们的结果表明，0.15-0.25um范围内的颗粒群组分可以作为超温流的敏感指标，这种超温流通常是由大约0.593-0.613 Ma以来来自裂谷南缘的河流洪水触发的。这些高密度的羽状物来自南方裂谷较长的河流，这些河流在大约0.593-0.613 Ma之前很普遍。当沉积物作为半远洋沉积提供时，在0.3-0.5微米范围内的总粒度人口的比例成为悬浮沉降物沉积的一个指标。岩芯在海相时期显示出较粗的沉积物，这可能与伊什特米亚海峡开放相关的洋流环流有关。因此，这项研究说明了盆地间海峡的建立如何影响邻近沉积中心深水轴的沉积水动力学细节。
Grain-size analysis of the sediments in borehole M0079A, located in the Corinth Rift, was used to explore hydrodynamic conditions and provenance in the Late Pleistocene Corinth Rift. Grain-size populations that were sensitive to the sedimentary environments were characterized by frequency distribution, particle size–standard deviation and probability cumulative curves. Our results indicate the grain-size population component in the range 0.15–0.25 µm may be used as a sensitive proxy for hyperpycnal flows, which have commonly been triggered by river floods from the southern margin of the rift since c. 0.593–0.613 Ma. The high-density plumes derived from the longer rivers of the southern rift that were prevalent before c. 0.593–0.613 Ma. When sediment is supplied as hemipelagic deposition, the proportion of the total grain-size population that is in the 0.3–0.5 µm range becomes an index for suspension fall-out deposits. The core shows coarser sediments during the marine periods, and this may be linked to the current circulation related to the Ishtmia Strait opening. The study thus illustrates how the establishment of interbasinal straits can influence the details of sedimentary hydrodynamics in the deep-water axis of an adjacent depocentre.