地震地质 ›› 1992, Vol. 14 ›› Issue (2): 121-128.

• 科研简报 • 上一篇    下一篇

哀牢山-红河剪切带的热年代学研究-多重扩散域模式的应用实例

陈文寄1, T M 哈里森2, O M 洛弗拉2   

  1. 1. 国家地震局地质研究所 北京 100029;
    2. 美国加州大学洛杉矶分校地球和空间科学系 CA 90024
  • 收稿日期:1990-08-31 出版日期:1992-06-03 发布日期:2009-11-25
  • 基金资助:
    地震科学联合基金(89296)

THERMOCHRONOLOGY OF THE AILOSHAN-RED RIVER SHEAR ZONE-A CASE STUDY OF MULTIPLE DIFFUSION DOMAIN MODEL

Chen Wenji1, T M Harrison2, O M Lovera2   

  1. 1. Institute of Geology, State Setsmological Bureau, Beijing 100029;
    2. Dept.of Earth & Space Sci., UCLA, Los Angeles, CA 90024, U.S.A.
  • Received:1990-08-31 Online:1992-06-03 Published:2009-11-25

摘要: 洛弗拉等人(1989)把Dodson(1973)建立的单一扩散域模式扩展成矿物扩散域不连续分布的模式,即多重扩散域模式,与之对应具有某一封闭温度范围,因此利用单个K-长石矿物样品可以揭示更长时间段上的冷却过程。对云南哀牢山-红河剪切带的K-长石样品(FA-2-1)进行40Ar/39Ar同位素分析,利用多重扩散域模式,揭示在距今约20~19Ma问该带存在一快速冷却过程,这与西藏南部曲水地区快速抬升的时间是一致的。

关键词: 哀牢山-红河剪切带, 多重扩散域模式, 冷却历史

Abstract: Recently,the single-diffusion-domain closure model of Dodson (1973) has been extended to apply to minerals with a discrete distribution of domain size,multi-deffu-sion-domain closure model (Lovera et al.,1989).Because these domains contain a range of closuer temperatures,Lovera et al.(1989) found that a single K-feldspar samples may reveal a broad segment of a cooling history,rather than the single datum usually expected.A study of K-feldspar (FA-2-1) from the Ailao Shan/Red River shear zone,Yunnan,reveals extremely rapid cooling in the interval 20 to 19 Ma using the new model.In consistent with the earlier published analysis involving many biotite samples and a K-feldspar sample collected from Quxu area,southern Tibet.We believe that the two results are related.These two studies underscore the value of using the domain disstribution hypothesis in tectonic studies and presage a revolution in "tectonic geochro-nology".

Key words: Multi-diffusion-domain model, Thermochronology, Ailoshan-Red River shear zone