Qian Chao

China National Petroleum Corporation | CNPC

CO2 injection is a promising technology for enhancing gas recovery (CO2-EGR) that concomitantly reduces carbon emissions and aids the energy transition, although it has not yet been applied commercially at the field scale. We develop an innovative workflow using raw data to provide an effective approach in evaluating CH4 recovery during CO2-EGR. A...

The issue of inter-well fracture channeling in shale reservoirs is becoming increasingly prominent, significantly impacting the production of nearby wells. Therefore, it is crucial to accurately determine the location of fracture channeling in order to effectively design anti-channeling measures and optimize reservoir fracturing. In this paper, a d...

The relationship between fracture calcite veins and shale gas enrichment in the deep Ordovician Wufeng Formation-Silurian Longmaxi Formation (Wufeng-Longmaxi) shales in southern Sichuan Basin was investigated through core and thin section observations, cathodoluminescence analysis, isotope geochemistry analysis, fluid inclusion testing, and basin s...

The influence of geological and engineering factors results in the complex production characteristics of shale gas wells. The productivity evaluation method is effective to analyze the production decline law and estimate the ultimate recovery in the shale gas reservoir. This paper reviews the production decline method, analytical method, numerical...

The accuracy of adsorbed gas content under actual in situ reservoir conditions is crucial for the evaluation of shale gas reserves. In this study, the characteristics of methane adsorption on the Wufeng-Longmaxi shale were investigated under a wide range of pressure (0-51 MPa) and actual in situ water saturation. Methane-shale adsorption exhibits t...

Various shale lithofacies differ significantly in terms of gas content and pore structure characteristics. In this study, FE-SEM, low-pressure gas adsorption (LPGA), in-situ reservoir water saturation restoring, and high-pressure (0~51Mpa) methane adsorption were conducted to systematically characterize pore structure and evaluate the gas content o...

Since the accurate early gas well production regime is related to the production period and final productivity, it is crucial to make better use of early flow stage production data for gas well productivity evaluation. Absolute open flow potential (AOF) and estimated ultimate recovery (EUR) are essential parameters for evaluating the productivity o...

This paper aims to study the influence of deep formation conditions on the mechanical properties of shale, which is of great significance for the engineering application of efficient development of deep shale gas. In this study, a real‐time high‐temperature (25°C–170°C) triaxial compression experiment was first carried out on shale samples. Then, b...

Twelve shale fracture veins and forty-nine fluid inclusion assemblages within the veins of 3800−4200 m in three wells located in different tectonic zones in the Yuxi Region, southern Sichuan Basin were selected in this study. The burial and thermal histories of single wells were reconstructed, and time− temperature−pressure of oil and gas filling w...

Wells with low gas content and low resistivity in the Changning area, southern Sichuan Basin were selected for this study. The burial-thermal history was reconstructed and the characteristics of multi-phase fluid activity were clarified using microscopic observation and testing of fluid inclusions in the Longmaxi shale fracture veins. Compared with...

Herein, integrated vertical variation characteristic analysis was conducted by measuring total organic carbon (TOC), major and trace elements in Upper Ordovician-Lower Silurian (Wufeng-Longmaxi formations) black shale in Weiyuan, Luzhou, and Changning areas, southern Sichuan Basin to clarify the control of organic matter (OM) enrichment in differen...

In southern Sichuan Basin, the main production layers are characterized by deeply buried, high stress difference, and complex structural conditions. The Luzhou area is far from large faults, and natural fractures are greatly important for shale gas storage and production. Multi-scale natural fractures control the migration, enrichment, and preserva...

Gas content and flow characteristics are closely related to the shale lithofacies, and there exist significant differences in the pore structure and fractal characteristics among lithofacies. In this study, X-ray diffractometer, field-emission scanning electron microscopy (FE-SEM), gas adsorption (N2 and CO2), and fractal theory were employed to sy...

Understanding the changes of the near-wellbore pore pressure associated with the reservoir depletion is greatly significant for the development of ultra-deep natural gas reservoirs. However, there is still a great challenge for the fluid flow and geomechanics in the reservoir depletion. In this study, a fully coupled model was developed to simulate...

Deep shale gas reservoirs are a significant alternative type of shale gas reservoir in China. The productivity of deep shale gas wells is lower than that of shallow shale, and the imbibition characteristics of deep shale have a significant effect on the retention and backflow of fracturing fluid and the productivity of shale gas wells. In this stud...