Lancaster EPrints

Paleorainfall Reconstructions from Pedogenic Magnetic Susceptibility Variations in the Chinese Loess and Paleosols.

Maher, Barbara A. and Thompson, Roy (1995) Paleorainfall Reconstructions from Pedogenic Magnetic Susceptibility Variations in the Chinese Loess and Paleosols. Quaternary Research, 44 (3). pp. 383-391. ISSN 0033-5894

Full text not available from this repository.

Abstract

The rock magnetic properties of the Chinese loess and paleosols constitute a unique and sensitive record of East Asian paleoclimate through the Quaternary Period. Systematic variations in the concentration and grain size of the magnetic minerals in these sediments have produced systematic variations in the magnetic susceptibility signal, which can be easily and rapidly measured at many sites across the Loess Plateau. Variations in many other rock magnetic properties can be used to identify the key shifts in ferrimagnetic grain size, but magnetic susceptibility alone is sufficiently sensitive to record stadial and interstadial climate stages, as well as glaciations and interglaciations. Past changes in rainfall and monsoon activity for this region are reconstructed from the susceptibility variations. The susceptibility record is calibrated using the modern relationship between rainfall and pedogenic susceptibility on the Loess Plateau. Our rainfall reconstructions identify enhanced summer monsoonal activity in the Chinese Loess Plateau region in the early Holocene and the last interglaciation. In the presently semiarid western area of the plateau, annual precipitation in interglacial times was up to 80% higher than at present; in the more humid southern and eastern areas, values were up to 20% higher than today's levels. During the last glaciation, precipitation decreased across the entire plateau, typically by 25%. The relationship between pedogenic susceptibility, climate, and weathering age was examined over the Northern Hemisphere temperate zone and the observed positive correlation between rainfall and susceptibility indicates that climate, rather than soil age, is the predominant factor that controls pedogenic susceptibility enhancement in loess soils.

Item Type: Article
Journal or Publication Title: Quaternary Research
Uncontrolled Keywords: soil magnetism ; Quaternary palaeoclimate ; palaeorainfall ; loess ; palaeosols
Subjects: G Geography. Anthropology. Recreation > G Geography (General)
Departments: Faculty of Science and Technology > Lancaster Environment Centre
ID Code: 301
Deposited By: Professor Barbara A Maher
Deposited On: 02 Jan 2007
Refereed?: Yes
Published?: Published
Last Modified: 26 Jul 2012 16:48
Identification Number:
URI: http://eprints.lancs.ac.uk/id/eprint/301

Actions (login required)

View Item