Submarine Landslide Identified in DLW3102 Core of the Northern Continental Slope, South China Sea

摘要

In this paper,we take DLW3101 core obtained at the top of the canyon (no landslide area) and DLW3102 core obtained at the bottom of the canyon (landslide area) on the northern continental slope of the South China Sea as research objects.The chronostratigraphic framework of the DLW3101 core and elemental strata of the DLW3101 core and the DLW3102 core since MIS5 are established by analyzing oxygen isotope,calcium carbonate content,and X-Ray Fluorescence (XRF) scanning elements.On the basis of the information obtained by analyzing the sedimentary structure and chemical elements in the landslide deposition,we found that the DLW3102 core shows four layers of submarine landslides,and each landslide layer is characterized by high Si,K,Ti,and Fe contents,thereby indicating terrigenous clastic sources.L 1 (2.15-2.44 m) occurred in MIS2,which is a slump sedimentary layer with a small sliding distance and scale.L2 (15.48-16.00 m) occurred in MIS5 and is a debris flow-deposited layer with a scale and sliding distance that are greater than those of L1.L3 (19.00-20.90m) occurred in MIS5;its upper part (19.00-20.00 m) is a debris flow-deposited layer,and its lower part (20.00-20.90 m) is a sliding deposition layer.The landslide scale of L3 is large.L4 (22.93-24.27 m) occurred in MIS5;its upper part (22.93-23.50 m) is a turbid sedimentary layer,and its lower part (23.50-24.27 m) is a slump sedimentary layer.The landslide scale of L4 is large.