The hole RM, the deepest one fully obtained from the core in the Tibetan Plateau, is situated in the depocenter of the Zoie Basin(33°57′N; 102°21′E)in northeastern Tibetan Plateau with a depth of 310.46 m. From 14 C dating and paleomagnetic stratigraphic study, the core RM dated back to 900 ka B.P.. In this paper we analyzed the compositions of 18O and 13C in various carbonates(snail, obstrode, chemical carbonate)in core RM and discussed preferably the paleoclimatic record by the proxies of δ 18O and δ 13C of chemical carbonate(authicarbonate)from core RM in the past 140 ka.. The results show that the values of δ 18O in various carbonates are generally identical, and the values of δ 13C in it are inconsistent while there exists a better relativity. The studies also demonstrate that there is a negative correlation between δ 18O and δ 13C of authicarbonate in core RM in the past 140 ka, showing that the changes of δ 18O values is mainly relative to the water temperature. According to the above, the climatic evolutionary sequence in the past 140 ka in the region is rebuilt.
Wu Jinglu
. COMPOSITIONS OF 18O AND 13C IN VARIOUS CARBONATES AND THE SIGNIFICANCE OF CORE RM IN THE ZOIE BASIN[J]. SCIENTIA GEOGRAPHICA SINICA, 1997
, 17(1)
: 18
-23
.
DOI: 10.13249/j.cnki.sgs.1997.01.18
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