Science in China Series D: Earth Sciences

, Volume 40, Issue 2, pp 189–196

Pseudotachylytes from the Koktokay-Ertai fault zone, Xinjiang, China, and their seismogeologic implications

  • Lanbin Shi
  • Chuanyong Lin
  • Xiaoou Zhang
  • Xiaode Chen
  • Meixiang Bai
Article

Abstract

Multi-period of pseudotachylytes of variable occurrences and shapes are widely outcropped in Haizikou and Mukurasen sections of the Koktokay-Ertai fault zone. They consist of clasts and matrix. The clasts comprise fine fragments of the host rock (mylonite) and quartz grains, while the matrix consists of cryptocrystalline and glassy materials which contain fibrous and radial microlites. The chemical compositions of the pseudotachylytes resemble those of the host rocks. Their features indicate that the pseudotachylytes were formed from local melting of the mylonites during the rapid movement of the fault, and that the formation depth was 10—12 km. The geologic event that produced pseudotachylytes is believed to be paleoearthquake.

Keywords

Koktokay-Ertai fault pseudotachylyte mylonite paleoearthquake 

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Copyright information

© Science in China Press 1997

Authors and Affiliations

  • Lanbin Shi
    • 1
  • Chuanyong Lin
    • 1
  • Xiaoou Zhang
    • 1
  • Xiaode Chen
    • 1
  • Meixiang Bai
    • 2
  1. 1.Institute of GeologyState Seismological BureauBeijingChina
  2. 2.Seismological Bureau of Xinjiang Uygur Autonomous RegionUrumqiChina

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