油气成藏过程中的同位素测年方法评述

Isotopic dating techniques and their applications to the geochronology of hydrocarbon migration and accumulation:An overview

关键词:  同位素测年  激光显微探针技术  流体包裹体

Key words:  isotopic dating technique  laser microprobe dating technique  fluid inclusion

摘要:

笔者对国内外同位素测定年在确定油气成藏方面的应用现状进行评述的基础上,重点分析了K-Ar法,Ar-Ar法,U-Pb法,Rb-Sr法等方法所存在的问题,认为自生伊利石⁴⁰Ar-³⁹Ar法在不断克服技术难题之后,仍是油气成藏年代学不可缺少的重要手段;激光微区探针⁴⁰Ar-³⁹Ar法与流体包裹体技术相结合,是油气多期成藏⁴⁰Ar-³⁹Ar年代学研究取得成功的突破点;利用沥青和干酪根中微量金属U-Pb,Pb-Pb,Rb-Sr,Sm-Nd和Re-Os体系的同位素分析方法获得油气生成、运移的年龄,是成熟的放射性同位素方法在石油地质学中的应用;晶洞充填物U-Pb测年,可能是碳酸盐岩储层油气成藏年代学研究又一新的突破点。

Abstract:

The present paper gives a general review of the isotopic dating techniques including K-Ar,Ar-Ar,U-Pb and Rb-Sr methods and their applications to the geochronology of hydrocarbon migration and accumulation in China and foreign countries.With the innovation and development,the authigenic illite ⁴⁰Ar-³⁹Ar method is still an indispensable technique in the chronology of hydrocarbon migration and accumulation.The integration of fluid inclusion technique and authigenic K-feldspar laser microprobe ⁴⁰Ar-³⁹Ar dating technique has made a successful breakthrough in the ⁴⁰Ar-³⁹Ar geochronology of hydrocarbon migration and accumulation.The isotopic dating techniques including U-Pb,Pb-Pb,Rb-Sr,Sm-Nd and Re-Os methods for the trace metals from bitumen and kerogen are all successful radioactive isotopic techniques for the geochronology of hydrocarbon migration and accumulation in petroleum geology.Particularly,U-Pb age dating of the speleothems may be another new breakthrough in the geochronology of hydrocarbon migration and accumulation in carbonate reservoirs.