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Analysis of sediment provenance in the East Siberian Arctic Shelf is crucial for the understanding of source to sink pathways and their link to climatic and environmental changes. In this paper, we conducted detrital mineral analysis on surface sediments and one sedimentary core (LV77–41-1) from the eastern Laptev Sea and the western shelves of the East Siberian Sea. Based on the results of light and heavy mineral analysis in surface sediments, two distinct zones were identified in the eastern Laptev Sea: an eastern zone is characterized by sources from the Lena River and a northern zone is characterized by sources that transition from riverine dominance to more sea-ice transported sources in an offshore direction. In the western part of the East Siberian Sea, detrital mineral assemblages in the outer Indigirka River mouth region are influenced by polygenic sources comprising sediments mainly derived from the river itself, and some material supplied by the Siberian Coastal Current, and the erosion of coastal permafrost and nearby islands. In the outer shelf and basin region, detrital mineral assemblages contain signatures of apatite, garnet, and hypersthene, indicating various material sources are represented, including the Lena River, Taimyr Peninsula, and Kamchatka Peninsula. Integrating this understanding of the sources and transport pathways of surface sediments, detrital mineral analysis of core LV77–41-1 indicate that coarse-grained Holocene sediments were mainly transported by the Indigirka River, with subordinate sources from coastal permafrost erosion, materials carried by Siberian Coastal Current, and island erosion. Since 7 ka BP, four distinct fluvial events have occurred, with the most prominent fluvial event occurring between 4.6 and 4.3 ka when the depocenter shifted significantly toward the sea. The fluvial events occurred following the onset warm periods and the high frequency of volcanic glass observed in layers marking these fluvial events serves as evidence of the influx of glacial meltwater into the Indigirka River basin during these warmer episodes. • Northern Laptev Sea shows a transitional zone with less river input and more sea-ice transport. • Sediments in outer shelf, basin originate from Lena, Taymyr, Indigirka, Kamchatka. • Since 7 ka, four major Indigirka River floods linked to warm periods, evident in volcanic glass distribution. • Sediments have predominantly come from river inputs and coastal erosion since 7 ka, with reduced erosion after 3.5 ka. [ABSTRACT FROM AUTHOR]

Abstract Detrital minerals in sediments can provide insight into sedimentary provenance and depositional environments. Here we report a record of heavy minerals of a 300.1 m long core recovered from the western south Yellow Sea, which was dated back to the late Pliocene (~3.5 Ma). Results of detrital mineral analysis show that sediments are dominated mainly by silicate minerals sourced from the Chinese mainland through river inputs. Heavy minerals suggest that marine transgression occurred around 76–84 m depth of the core depth, about at 792–840 ka BP. The upper part of the core (0–76 m) is dominantly marine and the lower part (below 84 m) is terrestrial. From the Miocene to Early Pleistocene, the Yellow Sea area generally subsided; the deposition center began to move from west to east, therefore the content of fine sand increased relatively in the core sediment. Meanwhile, under the influence of depression evolution in the Subei Basin, the paths of rivers were shifted, as a result the contents of augite and garnet changed, sediments in the study area were dominated by proximal sediments sourced from the Subei Basin, possibly of mixed sediments of the Yellow River and Yangtze River. The lower part of the core was characterized by a dramatic increase in augite with hornblende and epidote as dominant minerals. In the Early Pleistocene, under the background of subsidence in the Yellow Sea area, while transgression occurred, rivers shifted southward. Comparison with the mineral composition of adjacent core NHH01 and surface sediments from the region suggests the Yellow River dominated the study area, and the old Yangtze River input being occasionally dominant. The heavy mineral assemblage was dominated by hornblende and epidote, as well as mica, garnet and authigenic pyrite in some sediment layers. [ABSTRACT FROM AUTHOR]

Study of sediment sources and transport pathways in the Chukchi and East Siberian Seas is vital for understanding the interaction of fluvial, ocean, and sea-ice dynamics. In this study, 42 samples were analyzed for heavy minerals and 23 were analyzed for garnet geochemistry. These analyses suggest that the surface sediment is mainly sourced from the surrounding rivers. There are distinctive performances between the heavy minerals and garnet geochemistry of sediments in the Chukchi Sea and the East Siberian Sea. The content of hypersthene increased significantly on the outer shelf of the Chukchi Sea. The garnet was derived from volcanic rocks of the Okhotsk-Chukotka volcanic province and transported from the Gulf of Anadyr by the Pacific inflow. Coastal erosion materials dominated in the inner shelf of the Chukchi Sea. A significant amount of river input occurred in the western, middle, and eastern parts of the East Siberian Sea. The inputs from the Indigirka River and Kolyma River tend to be distributed eastward. The garnet geochemistry shows that there was a mixed sedimentary zone located south of Wrangel Island. The sediments in the outer shelf of the East Siberian Sea show a stable mixed sedimentary environment. [ABSTRACT FROM AUTHOR]

Data on grain size and heavy mineral composition for surface sediments on the Prydz Bay continental shelf was analysed to identify sediment features and provenance. The grain size composition of surface sediments indicate spatial variations in the glaciomarine environment and the key factors influencing sedimentation, which on the shelf include topography/water depth, currents and icebergs. The study area was divided into two sections by Q-type factor analysis: section I included Prydz Channel, Amery Basin and Svenner Channel, and section II included Four Ladies Bank, Fram Bank and the area in front of the Amery Ice Shelf. Sedimentation in section I is mainly controlled by currents and topography/water depth. However, in section II, icebergs/floating ice masses, the Amery Ice Shelf and currents have prominent effects on sedimentation. The heavy mineral composition indicates that surface sediments on the eastern side of the bay, including Four Ladies Bank, are primarily derived from Princess Elizabeth Land. Sediments in the area in front of the Amery Ice Shelf, Svenner Channel, Amery Basin and Prydz Channel have a mixed source from the eastern regions around the bay, including the Prince Charles Mountains and Princess Elizabeth Land. The contribution from Mac. Robertson Land to sediment at Fram Bank is limited. [ABSTRACT FROM PUBLISHER]

To understand the modern sedimentation and land-sea interaction processes in the Sunda Shelf, we evaluated the rare earth element (REE) compositions, the total organic carbon (TOC) contents, grain sizes, and detrital minerals of 39 surface sediments, collected from the western Sunda Shelf. All of the sampled sediments are characterised by a higher content of light REEs (LREEs) relative to the content of heavy REEs (HREEs) with negative Eu anomalies. The total content of REE (ΣREE) in the sediments ranges from 7 μg/g to 193 μg/g, with an average of 119 μg/g. Due to the uneven spatial distribution of REEs in the study area, a Q-cluster analysis is applied to the mean grain size (Mz), ∑REE, δEu, δCe, (La/Yb) N , and (Gd/Yb) N data. On this basis, the study area can be classified into three geochemical provinces. The north to central zone in the study area is designated as province I, which has the highest REE content among the three provinces. This is a result of the finer grain size, dominance of siderite, and higher TOC contents of the sediments in province I. The REE content of province II in the southwest coastal zone is lower than that of province I due primarily to a coarser grain size and high quartz, biodetritus, and plagioclase contents. Covering the central coastal zone, province III has the lowest REE content among the three provinces because of the extremely coarse grain size and very high quartz and biodetritus contents. The upper continental crust (UCC)-normalised REE patterns differ markedly among the three provinces, thereby indicating different provenances and transport mechanisms. Based on the provenance discrimination plot and the UCC-normalised REE patterns of these three provinces and adjacent rivers, we infer that province I is largely fed by the Mekong and Kelantan rivers. The fine-grained sediments from these rivers are transported to north and central zone by the northeast monsoon current. The Pahang River is identified as the main sediment source of province II. The coarse-grained sediments from this river mostly accumulate near the estuary via hydrodynamic sorting, while finer-grained sediments are transported to the south by the southward coastal currents. The sediments in province III are inferred as being primarily the result of coastal erosion due to the strong wave energy in this area, as well as offshore and longshore sediment transport acting, in parallel to the coast line. Our study can serve as a reference for studying the diffusion and transport processes of mountainous river sediment and the evolution of the paleoclimate and paleoenvironment in tropical low-latitude regions. • Surface sediments of the western Sunda Shelf can be classified into three geochemical provinces. • Grain size and heavy minerals play important constraint roles on REE distribution. • Different geochemical provinces have their unique provenances. • Erosion, transport and deposition are mainly controlled by northeast monsoon current, coastal current and wave energy. [ABSTRACT FROM AUTHOR]