oa INFLUENCE OF CLASTIC MINERALS ON THE PHASE BEHAVIOR OF HYDROCARBON

To predict the phase state of the petroleum in these deep-buried reservoirs accurately would be of great benefit in further exploration and development. However, the influence of reservoir minerals on phase behaviors of crude oil in deeply buried reservoirs remains poorly understood. Here we report on our investigation of the influence of common siliceous minerals (quartz, feldspar, montmorillonite, illite) on the cracking and phase behavior of crude oil. We demonstrated that the common minerals found in clastic oil reservoirs have complicated influences on the thermal cracking behavior of crude oil. Further analyses showed that the PVT phase characteristics of the crude oil can also be related to the minerals present. Clay minerals, and especially montmorillonite, significantly change the dew point temperature and bubble point pressure. However, when Ro values exceed 2.0%, even when montmorillonite content reached 40 wt. %, the phase behavior of crude oil does not change significantly.