如何实现油气成藏期的精确定年

How to Achieve the Precise Dating of Hydrocarbon Accumulation

随着油气田"精细勘探"的进一步发展,油气藏的精确定年日益成为一种必要。目前可实现油气藏精确定年的方法多依靠放射性同位素体系,如钾—氩、氩—氩和铼—锇等。按照所测定样品的不同,又分为成藏矿物定年、油气包裹体定年和储层有机质定年等。但在实际勘探工作中,受地质定年理论或实验方法学的影响,单一定年技术所提供的年代数据的准确度和精密度仍有所欠缺,在对地质事件的解释上也容易产生一些疑议。在如何实现油气成藏期精确定年这项命题上,不仅需要不断地提高和改进实验分析技术,还需要完善定年方法的基础地质理论,以实现对数据结果的合理解释。油气成藏年代学分析不能仅仅停留在单一的方法技术上,应从各油气藏的特点出发,寻找与油气成藏直接相关的产物,采用多技术手段,获得较全面的年代学信息。

With the further development of ＂precise exploration＂ of oil and gas reservoirs,accurate dating ot hydrocarbon accumulation is increasingly becoming a necessity. Most of the methods used to achieve the precise dating were through the radioisotope systems,such as K-Ar,40 Ar-39 Ar or Re-Os. Due to different samples,it includes the dating of diagenetic minerals related with the hydrocarbon migration,the dating of organic matters in the reservoir of oil or gas,and the dating of inclusions of oil or gas. However,for the im- perfect or faulty of these dating methods in principle or experimental methodology, the accuracy and preci- sion are still lack in the actual exploration work. Furthermore, the interpretations of geological events are still full of speculation and uncertainty. On the proposition of how to achieve the precise dating of hydrocarbon accumulation,we still need to improve the theoretic research and experimental analysis techniques to give much more reasonable explanation. Therefore, the geochronology analysis of hydrocarbon accumulation should not just stay on the single technology. We should combine the characteristics of each oil or gas reservoirs,search the direct products related to hydrocarbon accumulation, to obtain more comprehensive chronological information using multi-technology means.