| |
 |
UNIVERSITY OF BUCHAREST
FACULTY OF PHYSICS Guest
2024-11-24 9:34 |
 |
|
|
|
Conference: Bucharest University Faculty of Physics 2011 Meeting
Section: Atmosphere and Earth Science; Environment Protection
Title:
A continuous time scale for Romanian loess based on magnetic data
Authors:
C. Necula(1), F. De Ridder(2), C. Panaiotu(1), A. Timar Gabor(3), S. Vasiliniuc(4), D. Dimofte(5)
Affiliation:
(1)Faculty of Physics, Paleomagnetic Laboratory, University of Bucharest, N. Balcescu 1, 010041 Bucharest, Romania,
(2)Earth System Sciences & Department Geography, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
(3)Faculty of Environmental Science, Babes-Bolyai University, Fantanele 30, 400294 Cluj Napoca, Romania
(4)Laboratory of Mineralogy and Petrology (Luminescence Research Group), Department of Geology and Soil Science, Ghent University, Krijgslaan 281 (S8), B-9000 Ghent, Belgium
(5)Faculty of Geology and Geophysics, University of Bucharest, N. Balcescu 1, 010041 Bucharest, Romania
E-mail
c3necula@yahoo.com
Keywords:
Dating, Loess, Time Base Distortion, Magnetic Susceptibility, Sedimentation Rate
Abstract:
Magnetic susceptibility of loess deposits is widely used as a proxy for major paleoclimatic changes during the Quaternary. Establishing a reliable chronology for magnetic susceptibility variations in loess is thus very important for the reconstruction of past environments. We have developed a new method to extract information about loess sedimentation history. A global ice volume model is used as a signal model for magnetic susceptibility recorded in loess. The novelty of this work is twofold. On the one hand, a new algorithm is proposed to date paleoclimatic records. On the other hand, the first continuous time scale for magnetic susceptibility recorded in loess is determined thus ensuring a continuous representation of sedimentation rate. The method is applied to two loess sequences from Romania. The results show that the new time bases for loess deposits are in concordance with the OSL and IRSL independent age measurements. Also, a strong link between magnetic susceptibility variations recorded in loess and the global ice volume was found. Accumulation rates derived from the new time base show fluctuating loess sedimentation in agreement with OSL derived accumulation rates. Furthermore, accumulation rates derived from the new time base correlate well with the grain size distribution for the last two glacial periods, indicating that loess was deposited in strong winds climatic conditions.
Note: The work of Cristian Necula was supported by the strategic grant POSDRU/ 89 / 1.5 / S / 58852, Project „Postdoctoral programme for training scientific researchers“ cofinanced by the European Social Found within the Sectorial Operational Program Human Resources Development 2007-2013“.
|
|
|
|