TITLE:
Application of Fluid Inclusions in Reservoir Formation: A Case Study of Qilicun Oilfield in Ordos Basin
AUTHORS:
Jingwen Zhu, Shanshan Chen, Yuxuan Zhang
KEYWORDS:
Fluid Inclusion, Homogeneous Temperature, Reservoir Formation, Chang 6 Oil Formation, Qilicun Oil Field, Ordos Basin
JOURNAL NAME:
Open Access Library Journal,
Vol.9 No.12,
December
30,
2022
ABSTRACT: The formation time of the Chang 6 reservoir was determined semi-quantitatively by petrographic observation, fluorescence spectral analysis, homogeneous temperature test and salinity calculation of fluid inclusions in the Chang 6 reservoir of the Qilicun oilfield, as well as sonic time difference method to recover the stripping thickness of the strata at the end of the Early Cretaceous, based on the study method of burial-thermal evolution history map with homogeneous temperature cast points of inclusions. The results show that brine inclusions, gas-liquid brine inclusions and a few oil inclusions are mainly distributed in quartz healing microfractures and some feldspar grains, mainly oval or irregular in shape, with sizes ranging from 3 to 10 μm. The fluorescence colors of oil inclusions are mainly yellowish green and green; the fluorescence spectra of oil inclusions are similar to those of hydrocarbon associated brine inclusions. The analysis of the uniform temperature, salinity and burial history of the oil inclusions indicates that the oil reservoir in the Chang 6 section of the Qilicun field was formed in the Early Cretaceous (135 - 100 Ma) in the first stage, the initial filling period (135 - 120 Ma), and the second stage, the massive filling period (120 - 100 Ma). This study can provide some geological basis for oil exploration and development in the Qilicun field and adjacent areas.