Abstract Detail

Paleobotanical Section

Quan, Cheng [1], Liu, Yusheng [1], Utescher, Torsten [2].

Paleogene seasonal variation and climate evolution of northeast China.

The continental Paleogene climates have been well studied in Europe and North America, but very little is known from Asia because only a few climatic results were reported on particular geological intervals. Based on 29 floral assemblages from 8 well age-controlled fossiliferous sites, we here quantitatively reconstruct the climates throughout the Paleogene of northeast China and discuss related seasonal variations. Our results demonstrate that the gradient of the mean annual temperature (MAT) was fairly shallow (0.27 °C/1° latitude) during the Paleocene throughout this region. In the Eocene, the climates were equably distributed, but the seasonality was predominant in the region, indicated by obvious thermal and hydrological differentiations between winters and summers of the sites. The paleo-East Asian monsoon must have had intensified at least in the mid late Eocene, substantially shown by apparent differences in annual climate distribution of all the sites. Regarding the climatic evolution of northeast Chinese Paleogene, our quantitative results suggest that the MAT overall declined from a warm condition in the Paleocene and Eocene to a moderate condition in the Oligocene, sharing a comparable trend with those of marine records. Two significant cooling events are recognized in the early and mid Eocene with temperatures dropped 3.4 °C and 3.8 °C for the MAT, and 5.8 °C and 4.7 °C for the winter temperature, respectively, in similar magnitudes to corresponding variations of Europe and North America. Furthermore, the present results show that the MAT rebounded in the late mid Eocene and then decreased till the Oligocene, in consistent with the pattern of Europe in the mid Eocene to Oligocene interval.

Broader Impacts:

1 - East Tennessee State University, Department Of Biology, PO Box 70703, Johnson City, TN, 37614-1710, USA
2 - Bonn University, Steinmann Institute, Bonn, Germany

Keywords:
Paleogene climate evolution
seasonality
temperature gradient
quantitative reconstruction
Eocene cooling
northeast China.

Presentation Type: Poster:Posters for Sections
Session: P
Location: Khorassan Ballroom/Chase Park Plaza
Date: Monday, July 11th, 2011
Time: 5:30 PM
Number: PPB002
Abstract ID:154