Research Institute of Petroleum Exploration and Development

Molecular Mechanisms of CTAB-Induced Oil Droplet Detachment in Shale Nanopores

Abstract The efficient recovery of shale oil is severely hindered by the strong oil–solid interactions and nanoscale confinement within shale reservoirs, which substantially restrict crude oil mobility. Although surfactant flooding has emerged as an effective enhanced oil recover...

Mechanistic Analysis of Stage-Dependent In Situ Hydrogen Production from Heavy Oil Under Nitrogen Atmosphere

In situ gasification-assisted hydrogen production from heavy oil has the potential to simultaneously achieve in-reservoir upgrading and hydrogen generation, offering a promising pathway for the clean and efficient development of heavy oil resources. To investigate stage-dependent...

Experimental Measurement and Artificial Neural Network Prediction of Dew Point Pressure for Ultra-Deep Condensate Gas

The development of oil and gas resources in global petroliferous basins has extended from shallow to deep reservoirs. Dew point pressure (Pd) is a vital parameter for fluid characterization and field development. Accurately and quickly obtaining Pd is crucial for the development...

Mechanically Robust and Underwater‐Stable Hydrogels via Synergistic Molecular Locking and Topological Entanglement

ABSTRACT Highly entangled hydrogels typically suffer from swelling‐induced dilution of chain entanglements in aqueous environments, leading to compromised energy dissipation and mechanical integrity. Herein, we report an underwater‐stable and highly entangled poly(acrylamide–acry...

Geomechanical Characteristics of Cretaceous Ultra-Deep Sandstone Reservoirs in the Southern Keshen Area, Kuqa Depression: Implications for Exploration and Development

Significant progress has been made in exploring ultra-deep tight sandstone gas in the Tarim Basin, but sweet spot prediction remains challenging in the Keshen block of the Kuqa Depression. Based on integrated geological, experimental, and seismic data, this study characterizes th...

Coupling Simulation of Drilling Behavior in Cavity Bottom Sediments of Salt Cavern Gas Storage

In terrestrial salt cavern gas storage facilities in regions such as Jintan, China, the development of mud interlayers in the formation causes sediment to accumulate at the bottom of the cavern after water-based dissolution, occupying nearly half of the effective storage capacity...

Integrated field test and modeling study of CO2 geological storage with enhanced water recovery in Eastern Junggar Basin of Xinjiang

Xinjiang, a primary energy export hub in China, faces substantial carbon emission pressure and severe water scarcity, making CO 2 geological storage combined with enhanced water recovery (CO 2 -EWR) a win–win strategy to foster regional development and bolster national energy sec...

Experimental Study on Gas–Water Two-Phase Seepage Characteristics in a Low-Permeability Gas Reservoir

The relationship between two-phase flow behavior and pore microstructure in low-permeability gas reservoirs remains poorly understood, particularly during gas accumulation (gas displacing water) and subsequent development (water displacing gas). To address this, five plug cores w...

Mechanisms and Parameter Optimization of Pre-Fracturing Energy Enhancement in Ultra-Low-Permeability Tight Oil Reservoirs

Ultra-low-permeability tight oil reservoirs, including the Chang 6 and Chang 8 formations in the Changqing Oilfield and the Fuyu reservoir in the peripheral Daqing Oilfield, are characterized by poor reservoir properties and limited waterflooding efficiency. Conventional areal wa...

Unraveling the Scale Effect on Fracture Plugging: A Quantitative Study from Lab-Scale Slots to Field-Scale Fractures via Hydrodynamic Analysis

Abstract Conventional core-scale laboratory fracture-plugging tests may overestimate the ability of granular lost circulation materials (LCMs) to form a complete plugging zone under field-scale conditions. This discrepancy arises because the effects of increasing fracture length...

Reservoir quality evaluation of tight carbonate gas reservoirs using fractal–multifractal pore-structure metrics: a case study from the Taiyuan Formation, Ordos Basin, China

Abstract Tight carbonate gas reservoirs commonly contain appreciable storage space but highly variable flow capacity, making reservoir-quality evaluation and favorable-interval screening challenging in exploration and development. This study investigates 10 representative limesto...

A New Method to Improve the Accuracy of Total Organic Carbon Measurement in Carbonate Rocks

The methods for determining total organic carbon (TOC) in carbonate rocks are mainly the conventional TOC method and the montmorillonite thickening method. However, both methods suffer from organic matter loss during the measurement process and inaccuracy in determining low TOC c...

Efficacy, safety, and pharmacokinetics of pumecitinib nasal spray for moderate-to-severe seasonal allergic rhinitis: a multicentre, double-blind, randomised, placebo-controlled, phase 2 trial

Background Seasonal allergic rhinitis (SAR) is a pollen-triggered condition causing nasal inflammation and quality of life impairment. Pumecitinib, a topical Janus kinase (JAK) inhibitor may modulate allergic inflammation. We evaluated the efficacy, safety, and pharmacokinetics o...

Managing hydraulic fracturing-induced seismicity in the Duvernay shale: Triggering mechanisms, influencing factors, and practice-oriented mitigation strategies

Abstract This review provides a Duvernay-focused synthesis of hydraulic fracturing (HF)-induced seismicity, integrating geological datasets, case studies of significant events, coupled poroelastic simulations, and machine-learning-based factor ranking. While the three underlying...

Deciphering theSource and Formation Mechanism ofImmature Crude Oils in the Paleocene Linhe Formation, Hetao Basin

Abstract The discovered crude oil in the Linhe Formation of the Hetao Basin is a typical immature oil, with proven petroleum geological reserves exceeding 200 million tons, making it one of the most successful cases of low-maturity oil exploration in China in recent years. Howeve...

Diagenesis of UpperTriassic Chang 8 Sandstones, SouthwesternOrdos Basin, China: A New Insight into the Formation Mechanism ofChlorite and Calcite Cement

Abstract Authigenic minerals from Chang 8 sandstones can preserve a precise paleotemperature record. Petrographic observations and geochemical characteristics provide a new insight into the formation mechanism of chlorite and calcite and resolve the problems of mobile elements be...

OVT-Domain Azimuthal Traveltime-Constrained AVO Inversion Method

Azimuthal traveltime analysis provides comparatively stable fracture-orientation estimates but limited information on fracture-related elastic changes, whereas amplitude variation with offset (AVO) inversion is sensitive to residual azimuthal moveout. We propose a sequential offs...

Experimental study on CO2 flooding for enhanced oil recovery in ultra-low permeability reservoirs of the Songliao Basin

<title>Abstract</title> The Daqingzijing Oilfield in the Songliao Basin is characterized by low porosity and ultra-low permeability, exhibiting significant potential for CO ₂ flooding. To further clarify the impact of different CO ₂ injection methods on enha...

Sequential SolventExtraction Reveals Lithofacies-DependentPore Accessibility, Wettability, and Hydrocarbon Partitioning in Organic-RichLacustrine Shales

Abstract Understanding the reservoir characteristics of shale oil formations is an essential workflow in petroleum exploration and development because it supports petroleum-reserve evaluation and guides production activities. Few studies have examined the coupled effects of pore...

Paleozoic Tectonic Transition from Arc–Continent Collision to Post-Orogenic Extension in the East Kunlun Orogen: Constraints from Metamorphic Events

Abstract The tectonic evolution of the trench–arc–back-–arc basin system—encompassing back-arc spreading, subduction, basin closure, and the subsequent transition from arc–continent collision to post-collisional extension—represents a fundamental process in the evolution of the P...