Abstract:

       PVTX simulation of reservoir fluid inclusions has been widely applied to determine trapping pressures and
temperatures of inclusions, and in turn to reveal charge histories in petroleum reservoirs. In this paper, we present a case studyof the Middle Ordovician Yijianfang Formation carbonate reservoir in the Tuoputai area of Tarim Basin, using the VTFlinc
simulation method. Based on an integrated study of petrography, microthermometry, laser Raman spectrum, and confocal laser scanning microscope analyses, the inclusions were studied for forming stages, compositions, and thermodynamics. These further indicate the paleo-temperature and pressure of the inclusion formation. The petroleum charge time and stages are inferred. There were two stages in general, i.e., 420-405 Ma of the late Caledonian stage and 8-2 Ma of the late Himalayan stage. Previous work suggests that the Himalayan petroleum charge event of the Tahe oilfield did not reach here, but this study using the new method shows otherwise. Thus, the method is promising in applications.

Key words: fluid inclusion, PVTX simulation, VTFlinc, trapping temperature, trapping pressure, Tuoputai, Tarim Basin