Use of rubidium to date loess and paleosols of the Louchan sequence, central China

Citation
J. Chen et al., Use of rubidium to date loess and paleosols of the Louchan sequence, central China, QUATERN RES, 54(2), 2000, pp. 198-205
Citations number
39
Categorie Soggetti
Earth Sciences
Journal title
QUATERNARY RESEARCH
ISSN journal
00335894 → ACNP
Volume
54
Issue
2
Year of publication
2000
Pages
198 - 205
Database
ISI
SICI code
0033-5894(200009)54:2<198:UORTDL>2.0.ZU;2-S
Abstract
Rb concentrations, analyzed at 20-cm intervals from the Luochuan sequence o f loess and paleosols, are sensitive to the loess-paleosol alternation cont rolled by monsoon climate. Because it is geochemically immobile, Rb can be well preserved in the loess-paleosol sequence after deposition, and its con centration depends mainly on properties of the winter monsoon-blown dust an d on intensity of the summer monsoon-induced pedogenesis. A curvilinear rel ation has been developed between the measured Rb-concentration and the appa rent sedimentation rate for the last glacial-interglacial cycle. This relat ion provides a time scale that corresponds well with the presently accepted ages for paleomagnetic reversals of Brunhes/Matuyama and Jaramillo events. With allowance for reduced Rb concentrations caused by early Pleistocene c limate, the Rb-based time scale is also consistent with the boundary ages o f other major paleomagnetic reversals of the past 2.58 myr. (C) 2000 Univer sity of Washington.