Mineralogical and geochemical changes in the sediments of the Okhotsk Sea during deglacial periods in the past 500 kyrs

Reconstruction of Oceanographic Changes Based on the Diatom Records of the Central Okhotsk Sea over the last 500000 Years

“…Stage 8 was a very warm ice age, quite distinct from the other glacial periods. In support of our observations, this anomalous stage was previously examined by Barash et al (2006) and Lui et al (2006). In addition, previously determined alkenone-SST in the PC2 (Seki et al 2004a, b) suggest a warm event in Stage 5a and a cold period in early Stage 3; both these events are recognized in this study.…”

“…The previous study in this core (Lui et al 2006) utilized color b* analogous to MD012414 and MD012415, and built a reliable age model up. In this study, we also adopt this age model.…”

Sediment provenance variations in the southern Okhotsk Sea over the last 180 ka: Evidence from light and heavy minerals

“…The dominant minerals in core OS03-1 are quartz and plagioclase, which are consistent with other mineralogical and geochemical records available from cores MD01-2414 (Liu et al, 2006), OS03-1 (Zou et al, 2015) and LV28-42-4 & LV28-44-3 (Nürnberg et al, 2011). Core sediments investigated from the eastern part of Okhotsk Sea contain higher content of hornblende compared to cores from the western part of Okhotsk Sea and was deemed as derived from the Kamchatka Peninsula (Nürnberg et al, 2011;Sakamoto et al, 2005), while in the western Okhotsk Sea (PC4) the IRD was mainly supplied from the northern and the western continental margins .…”

“…The Okhotsk Sea, the northernmost boundary of permanent seasonal sea ice cover in the north Pacific, plays an important role in the regional and global climate, such as ventilating the intermediate water in the North Pacific. Based on various proxy evidences such as ice rafted-debris (IRD) (Liu et al, 2006;Nürnberg et al, 2011;Nürnberg and Tiedemann, 2004;Sakamoto et al, 2005;Sakamoto et al, 2006), microfossils (Gorbarenko et al, 2002;Itaki and Ikehara, 2004;Katsuki et al, 2010;Khusid et al, 2005;Okazaki et al, 2003aOkazaki et al, , 2003bShiga and Koizumi, 2000) and sea surface temperatures (SST) , these studies revealed that sea ice extent has varied in the Okhotsk Sea. For example, an extended but not perennial sea ice cover was present over a great part of the sea during the Last Glacial Maximum (LGM) (Shiga and Koizumi, 2000;Wang and Wang, 2008).…”

Late Quaternary paleoceanography of the northwestern Pacific: Results from IMAGES program

“…Modern observations suggest strong interactions between sea surface conditions in the northwestern Pacific and atmospheric conditions. For examples, southerly migration of the Oyashio Current are linked to seasonal changes in the strength of the Okhotsk high and Aleutian low pressure cells (Minobe, 1999); the extent of extreme anomalies of spring sea ice cover over the Bering and Okhotsk Seas is correlated with rainfall variability in the east Asian summer monsoon (Zhao et al, 2004); there is apparent relationship between El Niño Southern Oscillation (ENSO), the Okhotsk High-Aleutian Low pressure gradient and the Kuroshio and Oyashio (K/O) frontal migration (Nitta, 1987). Thus, past changes in the North Pacific likely had significant oceanographic and climatic implications that reached beyond this region.…”