40Ar/39Ar dating of plutonic/metamorphic rocks from Chinmen Island off southeast China and its tectonic implications

Lo Ching-Hua Lo, T. C. Onstott, Wang Lee Chihming Wang Lee

Research output: Contribution to journalArticle

21 Scopus citations

Abstract

To reconstruct the thermal history of the Yanshanian Orogeny in SE China, a combination of 40Ar/39Ar thermochronological and thermobarometrical techniques have been performed on hornblende, biotite and K-feldspar separates from a granite and gneiss sample from Chinmen Island. Based on closure temperature calculations and the isotopic dates of the minerals, the thermal history of the area is derived as follows: the region experienced plutonism/metamorphism prior to 101 Ma, cooled rapidly in the initial stages at a rate of ~80°C/Ma between 101 and 97 Ma, and then cooled slowly to 180°C at a rate of ~8°C/Ma until ~82 Ma. The fast cooling may reflect rapid tectonic uplifting. However, the plutonic/metamorphic complex was not exposed at the surface until the Miocene. A paleo-geothermal gradient of about 30°C/km has also been inferred. -from Authors

Original languageEnglish (US)
Pages (from-to)35-55
Number of pages21
JournalJournal - Geological Society of China
Volume36
Issue number1
StatePublished - Jan 1 1993
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Geology

Fingerprint Dive into the research topics of '<sup>40</sup>Ar/<sup>39</sup>Ar dating of plutonic/metamorphic rocks from Chinmen Island off southeast China and its tectonic implications'. Together they form a unique fingerprint.

Cite this