Time-scale and astronomical forcing of Serbian loess–paleosol sequences

Autor: Zhengtang Guo, Ulrich Hambach, Thomas Stevens, Biljana Basarin, Tin Lukić, Andjelka Kovačević, Ken O. 'Hara Dhand, Slobodan B. Marković, Bjoern Buggle
Rok vydání: 2014
Předmět:
Zdroj: Global and Planetary Change. 122:89-106
ISSN: 0921-8181
Popis: The loess in Vojvodina region in Northern Serbia is regarded as one of the thickest and most complete paleoclimate archives in Europe. Recent studies showed that loess in Vojvodina spans the last million years. Based on the interprofile correlation between two most important loess–paleosol sequences Stari Slankamen and Titel Loess Plateau a synthetic profile was formed regarded as Stratotype Record of Serbian loess (SRSL). The synthetic profile has a total thickness of 62 m and is comprised of 10 loess layers intercalated with nine pedocomplexes. A new astronomically tuned age model is proposed based on correlating peak magnetic susceptibility (χ) responses with the timing of June perihelia. This target curve is derived from analysis of regional climate proxy responses during the last interglacial and independently dated last glacial–interglacial cycle of Serbian loess–paleosol sequence. The use of a precession index target as the only tuning target presents the requirement of minimal tuning approach, which means that only the precession frequencies of the record will be manipulated. Spectral and wavelet analyses of tuned magnetic susceptibility record reveal the presence of frequencies corresponding to 139 kyr, 94 kyr, 65 kyr and small amplitude cycles of 43 and 23 kyr in χ record. Spectral analysis of frequency dependent magnetic susceptibility (χ fd ) has spectral content concentrated around 100 kyr and 77 kyr, while higher frequency cycles are below significance level. There is a strong 245 kyr peak in spectral results of both χ and χ fd records that needs additional attention. Around 800 kyr in SRSLχ time scale and between 900 kyr and 600 kyr in SRSLχ fd series the 100 kyr cycles become dominant, which could be identified as the period of Mid-Pleistocene Transition. This is the first record of this paleoclimate transition in the Pannonian basin. The results presented in this study highlight the potential of Serbian loess–paleosol sequences for investigation of detailed and long-term climate reconstruction over continental Eurasian extent.
Databáze: OpenAIRE