【摘要】 在断陷盆地形成过程中,火山活动频繁,在地层中残存较多的喷出岩。喷出岩作为盆地地层中的特殊岩性,具有与天然地震、断层活动时空分布的同一性以及原位沉积、时间标定等一系列特性。根据喷出岩基本特性,提出了一种研究油气运移时期的新方法——喷出岩标定法。该方法通过研究喷出岩的时空分布特征,确定相应地质历史过程中断层活动的地域和时间,结合烃源岩的成熟期,得到油气的有效运移断层;在假设该时期盆地沉积速率一定的基础上,研究断层附近喷出岩的埋深及期次,得到油气运移时间。该方法在喷出岩较发育的断陷盆地中可以广泛应用。利用该方法对深县凹陷沙三段烃源岩的油气运移时期进行了研究,得到油气运移时段为距今21.1~23.37Ma。更多还原

【Abstract】 The volcanic eruption often resulted in the effusive rocks in the rifted basin.The effusive rock is a special lithologic unit and has the same space-time distribution with the earthquakes and fault activities.The effusive rock often stands for the in-situ sediment and contains the age message.Based on the characteristics of the effusive rock,a new method called as effusive rock calibration method for studying the period of oil migration was proposed.Firstly,the position and time of fault activities were determined by studying the space-time distribution of effusive rocks.Secondly,the effective fault for oil-gas migration could be identified in combination with the mature period of source rocks.Supposing the deposition rate was changeless during this period,the time of oil migration could be determined by researching the burial depth and effusive stage of the effusive rocks near fault.This method can be applied in rifted basin with abundant effusive rocks.This method was used to determine the hydrocarbon migration period of source rocks in the third section of Shahejie Formation of Shenxian Depression.The oil migration period in first stage ranged from 21.1Ma to 23.37 Ma before present.更多还原