Science in China Series D: Earth Sciences

, Volume 45, Issue 5, pp 459–467 | Cite as

Discovery and implication of shock metamorphic unloading microfractures in Devonian bedrock of Taihu Lake

Article

Abstract

Sphenoidal tensile microfractures with particular patterns have been discovered in the Late Devonian quartzose sandstone in islands and peninsula of the Taihu Lake area. Microfractures present a ‘⋏’-shape collective pattern, occurring in a single row or multiple rows. The quartz crystals in the inner acute angle area of some ‘⋏’-shape microfractures have severely been non-crystallized, showing the feature of diaplectic glass. The studies show that these special microfractures were formed during the unloading process after the compression was up to the peak of an impact event.

Keywords

shock metamorphism unloading micro fracture Taihu Lake 

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Copyright information

© Science in China Press 2002

Authors and Affiliations

  1. 1.Department of Earth SciencesNanjing UniversityNanjingChina
  2. 2.Department of Environmental SciencesNanjing UniversityNanjingChina

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