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[Display omitted] • Sediments in OCVB and Kamchatka Peninsula were supplied to Okhotsk Sea shelf. • Intensive chemical weathering occurred on Okhotsk Sea shelf during glaciation. • Changes of sediment provenances affected the weathering records in the Holocene. • Climates and sea level were role factors on weathering patterns during glaciation. The Okhotsk Sea, a subarctic marginal sea with a wide shelf and abundant weathering products, provides ample information about the chemical weathering in the geological past. However, insufficient investigation in the Okhotsk Sea, especially in its shelf, limits our knowledge of the intensity of chemical weathering in high-latitudes. In this study, high-resolution geochemical elements compositions of the core LV87-54-1 were measured to reveal the provenance change in the Northern Okhotsk Sea Shelf since the Last Glacial Maximum (LGM) and to discuss the influential factors of the deep-sea weathering records. The elemental ratios suggested that the sediment provenance remained stable during 23–11.4 ka, mainly transported from the Okhotsk-Chukotka volcanic belt; whereas the sediment input from the Kamchatka Peninsula to the study area has been enhanced since 11.4 ka. During 23–14 ka, the chemical index of alteration (CIA) was observed to align with climatic changes in the Northern Hemisphere. Synchronized climatic deterioration (i.e., cooling and drying) in the Northern Hemisphere mainly contributed to the reduced alteration of the sediments eroded from the Okhotsk-Chukotka volcanic belt. During 14–11.4 ka, the reworking of older weathered sediments caused by sea-level rise overwhelmed climates in controlling silicate weathering, resulting in an increased alteration of sediments. During the Holocene, the core sediment witnessed a lower weathering degree, compared to the LGM–Deglaciation. We attribute this to an increased sediment input from the Kamchatka Peninsula that supplied more weaker weathered sediments to the study area. [ABSTRACT FROM AUTHOR]

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]