Testing age models for sedimentary sequences based on growth strata and the exhumation history of adjacent mountain ranges - Archive ouverte HAL Access content directly
Conference Papers Year :

Testing age models for sedimentary sequences based on growth strata and the exhumation history of adjacent mountain ranges

(1) , (2) , (3) , (4)
1
2
3
4
Feng Cheng
Andrew V Zuza
Marc Jolivet
Zhaojie Guo
  • Function : Author
  • PersonId : 952289

Abstract

High-resolution magnetostratigraphy is a powerful tool to provide age constraints for the sedimentary sequences, especially when integrated with independent means of age control (e.g., biostratigraphy, tephrostratigraphy). However, as the paleomagnetic correlation to the Geomagnetic Polarity Time Scale (GPTS) is non-unique, magnetostratigraphy alone could lead to dramatically different age models for the siliclastic sequences in the absence of fossils or volcanic ash layers. This challenge presented by different age models is exemplified in the debated Paleogene terrestrial strata in Central Asia, resulting in competing models that account for the growth of the Tibetan plateau and paleoclimate variations in Central Asia. The kinematic evolution of basin-bounding fault systems are interpreted via low-temperature thermochronology datasets from the basement rocks or by the well-dated growth strata in the sedimentary basin. Here we develop a new approach to test the magnetostratigraphy age model of sedimentary sequences in the basin. By comparing the timing of rapid exhumation of the basement rocks in the mountain belts with the initiation age of the growth strata shown on seismic reflections in the basin, we examine the magnetostratigraphy age model of sedimentary sequences in a number of intra-plate contractional and extensional systems (e.g., Zagros fold-thrust belt, Tian Shan fold-thrust belt, Shanxi rift). Our results show that the growth of each boundary fault revealed by two different ways is consistent, giving us confidence in applying this new approach to test the debated age model elsewhere. Adapting this new approach to the debated age models of Paleogene strata in the Tarim and Qaidam basins, we propose Paleocene-Eocene initial sedimentation along the northern margins of the Tibetan plateau, likely corresponding to crustal shortening in North Tibet simulations shortly after the initial India-Asia collision.
Not file

Dates and versions

insu-03937812 , version 1 (13-01-2023)

Identifiers

  • HAL Id : insu-03937812 , version 1

Cite

Feng Cheng, Andrew V Zuza, Marc Jolivet, Zhaojie Guo. Testing age models for sedimentary sequences based on growth strata and the exhumation history of adjacent mountain ranges. American Geophysical Union, Fall Meeting 2022 (AGU 2022), American Geophysical Union, Dec 2022, Chicago, United States. pp.T54A-01. ⟨insu-03937812⟩
0 View
0 Download

Share

Gmail Facebook Twitter LinkedIn More