基于传统吸附烃概念的烃类检测新技术

烃类是地表油气地球化学勘查地下油气藏的直接指标.目前我国油气化探中常用的酸解烃法检测出的烃类,不应定义为"吸附烃",它是介质吸收的产物,属结合态烃类,应定义为"吸收烃".地表酸解烃异常十分稳定,重现性好,能够很好地证明地质历史上曾经有过的烃类运移过程,但在反映目前深部油气信息方面具有多解性.针对酸解烃法的弱点,依据烃类垂向运移理论和物质吸附作用原理,自行设计开发、研制了一套吸附烃脱气装置,建立了土壤吸附烃提取新技术和检测方法.该方法有利于在近地表获取油气系统的动态信息,强化烃类测量法对其信息源的探测,可以提高地表油气化探预测油气分布的成功率.

NEW HYDROCARBON DETECTION TECHNIQUE BASED ON CONVENTIONAL CONCEPT OF ADSORBED HYDROCARBON

Hydrocarbon is a direct indicator to underground oil and gas reservoirs in surface oil and gas geochemical exploration. The hydrocarbon gas detected by acid-extraction method used at present in oil and gas geochemical exploration practice should be defined as "occluded hydrocarbon" instead of "adsorbed hydrocarbon", because this kind of hydrocarbon is combined with such media as soil grains. The surface anomaly of acid-extraction hydrocarbon is highly stable and has good repeatability, suggesting that the hydrocarbon migration process did occur during the geological history. Nevertheless, when used to reflect the information of deep oil and gas, the surface anomaly of acid-extraction hydrocarbon is subject to multi-interpretation. In view of this weakness of the acid-extraction method, a set of hydrocarbon desorption devices have been designed and developed, and a new extraction method and technique for soil adsorption hydrocarbon has been established. This newly developed hydrocarbon detecting technique can be used to collect the dynamic information of petroleum system at surface, intensify the study of hydrocarbon sources in the course of surface hydrocarbon measurement, and improve the prediction success ratio in surface oil and gas geochemical exploration practice.