## 4 Discussion
### Paleoenvironmental Implication for Sediment Provenance Changes  
Within the limits of our correlation-based dating model, we intend to discuss the implications of changes in sediment provenance concerning changes in the Arctic paleoenvironment. The identified provenance changes can be explained by several types of controls, including the configuration of ice sheets against sea level and climate conditions, sediment transport mechanisms, and oceanic circulation. Ice sheet sites and geometry at specific time intervals dictate the timing and location of major sediment discharge events into the Arctic Ocean [18]. Transport mechanisms further control sediment delivery to specific sites [8; 11; 18]. Quaternary marine sediments in the Arctic Ocean can be divided into three types: glacial, deglacial, and interglacial, mainly with respect to changes in the depositional environment caused by glaciation and subsequent sea-level change. The glacial sediments are olive-gray to yellowish in color, with scant microfossils, fine grain sizes, and a very low sedimentation rate [21; 27]. Sediments during the deglacial period with sea level rise are characterized by abundant IRD content transported by icebergs owing to the collapse of the ice sheet [21; 27]. Identified sediment provenance is possibly controlled by climate-dependent particle size. Here, we discuss the sediment transport and environment based on the sediment provenance changes. Figure 4: Discrimination plots showing variations in Q/F ratio vs. dolomite during (**a**) Cycle 1, (**b**) Cycle 2, and (**c**) Cycle 3. Mineralogical data of potential provenances are also shown for comparison [18]. Q/F: quartz/feldspar. Units 3, 5, and 8 likely correspond to the glacial/stadial sediments in core ARA09C-St03 (Figure 2). During the glacial periods, when the sea level was low, the Arctic Ocean  
Figure 5: Discrimination plots showing variations in K/C ratio vs. illite during (**a**) Cycle 1, (**b**) Cycle 2, and (**c**) Cycle 3. Clay mineralogical data of potential provenances are also shown for comparisons [18; 19]. K/C: kaolinite/chloride. experienced the exposure of the shallow continental shelves and the development of ice sheets and ice shelves. In addition, the input of terrigenous materials was limited by very thick perennial sea ice or even an extended ice sheet, which were recorded as low sedimentation rates in the basin [36]. Although the existence of ocean-based ice sheets remains controversial, most of the northern hemisphere's high-latitude land was occupied by large continental ice sheets such as the North American Ice Sheet and Eurasian Ice Sheet during the glacial periods [21]. The main sediment provenance of Units 3, 5, and 8 was identified as the illite-rich East Siberian Sea, possibly associated with glaciation of the adjacent Eurasian continental shelves (Figures 4 and 5). This is consistent with the results of earlier studies, and these fine-grained sediments may have been deposited predominantly by meltwater-derived suspension [37]. However, several differences can be observed in the incidental source regions of glacial units, which may be related to the scale of the ice sheet. Unit 7 appears to exhibit an influence from the Canadian Archipelago to a greater degree than other glacial units (Figure 4c). Sediment input from the Canadian Archipelago to the study area during this period was transported through the BG accompanied by icebergs or sea ice. However, because sediment transport through icebergs is accompanied by an IRD greater than 250 um, the low IRD content in Unit 7 means that some sediments from the Canadian Archipelago were mainly supplied through sea ice. It is possible that ice sheet development during this period was sufficiently weak to allow the circulation of some sea ice. However, for other glacial units, the sediment was sourced exclusively from the Eurasian continental shelf, likely indicating the strong development of the ice shelf compared to the stadial of MIS 5.