## 3 Results  
Previous studies found repeated cycles of brown and gray units and interbedded IRD-rich layers in numerous cores in the Arctic [2; 4; 8; 20; 22; 26]. The brown units are typically interpreted to reflect interglacial/interstadial environments with high primary productivity [2; 9]. In contrast, grayish units reflect the substantial reduction of biomass in glacial/stadial environments [2; 9]. In addition, IRD events may be caused by freely circulating icebergs [8; 23], and they have been reported as a feature of the deglacial period in the Chukchi Rise [21]. In Figure 2, Core ARA09C-St03 was divided into eight sedimentary units of three cycles based on the lithology such as sediment color, grain size, and IRD content. Each cycle contained one brown and one gray unit, and if the independent IRD-rich layer could be identified, it was classified as a separate unit. The sand content varies between 0% and 23.8%, with > 5% intervals at 61-89, 157-184, and 403-407 cm depth, which are associated with the IRD-rich layer. In the first cycle, Unit 1 (0 to 50 cm) consists mainly of brown sediment, including a surficial dark brown layer (B1). This unit contains a small amount of sand (max. 3.2%) and bioturbation. Unit 2 (50-93 cm) is dark gray and contains a significant amount of IRD and sand content (max. 23.4%), while Unit 3 (93-155 cm) is gray to yellowish-gray with fine-grained mud. The second cycle consists of Units 4 and 5. Unit 4's sediment (155-221 cm) is generally brown in color; however, it is characterized by relatively abundant IRD and sand content with PW layer (max. 19.4%). In addition, micronodules were found below the B2 layer and were identified through the chemical composition. Micronodules accounted for a significant proportion of the IRD particles. Unit 5 (221-332 cm) consists of a yellowish-gray to gray layer with fine-grained mud. The last cycle was divided into three units. Unit 6 (332-391 cm) sediment has a yellowish-gray to dark brown layer (B3). Unit 7 is generally gray in color and is classified as relatively abundant IRD and sand contents (max. 11.5%). Unit 8 is homogenous fine-grained gray mud. The mineral assemblage in samples from core ARA09C-St03 mainly consists of quartz, plagioclase, alkali feldspar, mica, dolomite, calcite, and clay minerals along with other minor minerals, such as halite, pyroxene, amphibole, and Fe-oxide minerals (hematite, magnetite, and maghemite). The vertical bulk mineralogy of core ARA09C-St03 is plotted in Figure 3. Quartz, the most abundant mineral in the sediment, averaged 23.9% (9.9-42.8%), and this mineral has the highest value in Unit 2 with abundant coarse particles as shown in Table 1. Plagioclase averaged 13.3% (5.6-22.5%), showing a particularly low amount in Unit 2. Carbonate minerals, such as dolomite and calcite, were generally abundant in the IRD-rich layers, including the PW layers, showing up to 17.4% and 4.3%, respectively. K-feldspar ranged from 3.2 to 7.1% (mean 4.3%), with the most abundant samples, similar to the depth of the dolomite peaks. The relative compositions of clay minerals are summarized in Table 2. The four clay minerals were dominated by illite (44.9-68.5%), followed by chlorite (14.1-21.8%), kaolinite (14.1-34.2%), and smectic (0.3-14.3%). Illite is the lowest in Unit 2 and also shows slightly lower values in Units 4 and 6-8. Kaolinite generally fluctuates between 14.1 and 15.0 but shows high values in Unit 2 up to 34.2%. Chlorite and smectic generally show opposite trends in the lower part of the core sediment. The \(\varepsilon\)Nd values of the separated clay fraction are from \(-13.8\) to \(-5.4\) (mean \(-8.9\)) in Table 3. Overall, they are between \(-7.7\) and \(-9.5\), and the lowest value is located in Unit 2.