- 서태평양 적도 지역의 플라이스토세 후기 고해양 변화
- ㆍ 저자명
- 유찬민,형기성,문재운,김기현,지상범,Yoo. Chan-Min,Hyeong. Ki-Seong,Moon. Jai-Woon,Kim. Ki-Hyune,Chi. Sang-Bum
- ㆍ 간행물명
- Ocean and polar research
- ㆍ 권/호정보
- 2004년|26권 2호|pp.175-185 (11 pages)
- ㆍ 발행정보
- 한국해양연구원
- ㆍ 파일정보
- 정기간행물| PDF텍스트
- ㆍ 주제분야
- 기타
To delineate Late Pleistocene paleoceanographic change of the West Pacific, we analyzed the oxygen and carbon isotopic ratios of two planktonic foraminifera species (G. sacculifer and N. dutertrei) from a piston core (KODOS-313) taken from the West equatorial Pacific, and they are compared with the published results of the East Pacific (ODP site 847 and RC 11-210), in terms of relative amounts and mass accumulation rates of $CaCO_3$ and eolian component, back to marine isotopic stage (MIS) 6. Differences in oxygen and carbon isotope values between two foraminifear species ($0.75%_{circ}$ in ${delta}^{18}O$, $0.05%_{circ}$ in ${delta}^{13}C$) are less than those of the East Pacific ($1.30%_{circ}$ in ${delta}^{18}O$, $0.14%_{circ}$ in ${delta}^{13}C$), which indicates smaller vertical contrasts in both temperature and nutrient between mixing-zone and thermocline in the West Pacific. Strong deviation in${delta}^{18}O$ of G. sacculifer from SPECMAP suggests the carbonate fraction of KODOS-313 was subjected to partial dissolution by bottom water under lysocline. Lower accumulation rates of $CaCO_3$ and eolian component during glacial times are likely due to low sedimentation rate (ave. 0.75 cm/1000 yr) combined with carbonate dissolution in KODOS-313 site. However, the high $CaCO_3$ contents during the glacial periods clearly follow the general pattern of equatorial Pacific ocean.