The eastern part of the Shichang Sub-sag in the Nanpu Sag is influenced by multiple provenance systems. However, there are divergent opinions regarding the directions of sediment supply and the relative contributions of different provenances to this area, which have led to controversies over the types of slope-breaks, the depositional models, and the sand-body distribution under different provenance regimes. These uncertainties have severely constrained the exploration of lithologic hydrocarbon reservoirs in the western slope area of the sub-sag. The provenance systems and the distribution range of sand bodies were clarified through Dickinson ternary diagrams, seismic reflection characterist... More >

The Junggar Basin contains widely distributed Jurassic low-rank coal seams (Badaowan Fm. J\(_1\)b, Xishanyao Fm. J\(_2\)x) with abundant coalbed methane (CBM) resources. Integrating proximate analysis, maceral identification, vitrinite reflectance, low-temperature N\(_2\) adsorption, high-pressure mercury intrusion, and NMR, this study characterizes the petrological properties, pore-space characteristics, and gas storage mechanisms of J\(_1\)b and J\(_2\)x low-rank coals in the Baijiahai-Dinan area. Results show: J\(_1\)b is bright coal (vitrinite: 74.1%-88.3%, R\(_o\): 0.67%), while J\(_2\)x ranges from semibright to dull coal (vitrinite: 57.2%, R\(_o\): 0.71%), corresponding to long-flame... More >

Geo-energy infrastructure—comprising oil and gas systems, CCUS, geothermal installations, and subsurface storage—is critical for energy security and low-carbon transitions. Yet disasters and engineering failures can trigger hazardous leaks and contaminant transport through complex geological media, posing cascading risks to subsurface and surface ecosystems. While urban resilience has been widely studied, environmentally resilient recovery strategies that explicitly integrate leakage risk, contaminant migration, and resource optimization remain underexplored. This review presents a digital twin framework for disaster-driven environmental recovery, unifying real-time monitoring, geologica... More >

Nanopores in shale are critical controls on shale gas storage and transport, and their formation, transformation, and preservation during geological evolution have long been major research topics in unconventional oil and gas geology. Considerable progress has been made in understanding the evolution of shale nanopore structures during sedimentation, diagenesis, and hydrocarbon generation from organic matter. However, the modification of shale nanopores by tectonic stress and the underlying mechanisms remain insufficiently understood. Organic-rich shale formations in South China commonly serve as regionally important detachment layers and have undergone multiple phases of tectonic activity i... More >

Analysis of fracturing flowback fluids from 14 shale gas wells across 7 platforms in the Zheng'an block, Guizhou, reveals that the fluids are characterized by high salinity, elevated Na\(^+\) and Cl\(^-\) concentrations, and high levels of chemical oxygen demand (COD) and ammonia nitrogen. Na\(^+\) concentrations range from 7370 to 27396~mg/L (mean 18689~mg/L), Cl\(^-\) from 9000 to 43000~mg/L (mean 29438~mg/L), and total salinity from 17074 to 70950~mg/L (mean 48744~mg/L). The dominant microbial populations comprise iron bacteria (FEB), saprophytic bacteria (TGB), and sulfate-reducing bacteria (SRB). These characteristics indicate that the flowback fluid cannot be discharged directly withou... More >

Shale gas horizontal wells in the Hongxing Block are challenged by long horizontal sections, narrow annular clearances, well-developed fractures, and the coexistence of lost circulation and wellbore collapse. Complexities such as pipe sticking, pump surging, annular blockage, and cuttings accumulation frequently occur during reaming, severely affecting operational safety and efficiency. To overcome the drawbacks of conventional empirical methods, this paper establishes four quantitative models: displacement-pressure coupling, bottomhole Equivalent Circulating Density (ECD) constraint, critical cuttings transport displacement, and drill string safety loading. An integrated reaming technology... More >

This study investigates the key factors controlling marine shale gas preservation in Devonian–Carboniferous strata, focusing on four representative synclines in the Nanpanjiang Basin and the northern margin of the Guizhong Depression: Langdai, Xinzhai, West Yizhou, and North Yizhou. Through tectonic characterization and balanced cross-section restoration, we clarify the effects of structural style, tectonic deformation intensity, and fault properties on shale gas preservation. Wide-gentle bidirectional thrust synclines (Xinzhai and West Yizhou) offer the most favorable preservation conditions, followed by the wide-gentle unidirectional thrust syncline (Langdai); the wide-gentle nappe-type... More >

Injected water quality critically determines waterflooding effectiveness. The southern area of Gaoshen, a major deep reservoir block of the Gaoshangpu Oilfield (Jidong Oilfield), faces severe injection-well plugging, increased injection pressure, failing injection rates, and rapid production decline—necessitating urgent water-quality optimization. This study conducts reservoir sensitivity evaluation, injected water–reservoir compatibility analysis, and single-factor experiments on the effects of solid particles, suspended oil, and bacteria on permeability. Results show: (1) The reservoir exhibits moderately strong water sensitivity (critical salinity: 6000--10000~mg/L); current injected-... More >