Article
 

Seismic strike-slip faulting and the development of the North China basin

Pubblico Deposited

Contenuto scaricabile

Scarica il pdf
https://ir.library.oregonstate.edu/concern/articles/3484zj51c

Descriptions

Attribute NameValues
Creator
Abstract
  • The actively subsiding North China sedimentary basin is associated with an unusually high level of seismic activity. This oil- and gas-producing basin has been the site of nine large (M ≥ 7), destructive earthquakes since 1600 A. D. An analysis of faulting during the Tangshan earthquake sequence, which includes some of the largest shocks that have occurred in this basin during the past 400 years, showed that the dominant pattern of deformation during this sequence was associated with displacement on right-stepping, right-la􀀊al strike-slip faults. A large amount of subsidence (~1.0-1.5 m) occurred in pull-apart regions between steps of the north­northeast (NNE) trending strike-slip faults. The directivity of the P wave radiation pattern and the distribution of aftershocks of the Bohai Gulf earthquake of July 18, 1969, also indicate strike-slip faulting on planes of similar NNE trend. Together with the four largest shocks of the Hsingtai sequence in 1966, earthquakes with right-lateral slip on NNE trending faults account for about two-thirds of the seismic moment released in this region for the past 100 years. The average regional strain due to seismic slip has a dominant component of dextral simple shear (on NNE striking planes) that is approximately twice as large as north-south extension or east-west shortening. Based on a combination of published field and borehole data, the dominance of horizontal dextral simple shear over subsidence seems to have begun no later than the mid­Pliocene and the total amount of extension over the entire basin is only about 20-30%. This pattern of deformation, the spatially variable heat flow values, the scattered locations of rapid deposition of Quaternary sediments, and the fluctuating rate of sedimentation in space and time during the Neogene in this basin are difficult to explain by pure extension and thermal subsidence. We propose that these observations, and the shape of the whole North China basin (that of a "lazy Z"), are a consequence of pulling-apart associated with right-lateral movement on the NNE trending strike-slip fault systems and that the basin as a whole has formed and evolved as a composite pull-apart basin due to right-lateral slip on numerous right-stepping faults since the Eocene.
Resource Type
DOI
Date Available
Date Issued
Citation
  • Chen, W., & Nabelek, J. (1988). Seismic strike-slip faulting and the development of the North China basin. Tectonics, 7(5), 975-989.
Journal Title
Journal Volume
  • 7
Dichiarazione dei diritti
Funding Statement (additional comments about funding)
  • NSF grants EAR86-07128 and EAR86-1845
Publisher
Language
Replaces

Le relazioni

Parents:

This work has no parents.

Elementi

Thumbnail Titolo Data caricata Visibilità Azioni
file details Chen_and_Nabelek_Tectonics_1988.pdf 2017-07-24 Pubblico Scaricare