Deep geotechnical engineering involves complex,hidden geology and high risks,making accurate rock classification critical.This study presents an intelligent prediction method that fuses image-text multimodal geophysical data via mileage-aligned survey images.A cross-modal matching model extracts fractured-rock features,localized by an object detector.Text descriptors,bounding-box sequences,and geological parameters are combined into a unified vector;a multi-output random forest predicts rock classes along mileage.Mutual correction between text and detection reduces false alarms and missed detections.Field tests show 92%accuracy,supporting intelligent advance forecasting.
Porous aquifer heterogeneity is a fundamental factor constraining the efficiency of groundwater remediation at contaminated sites.This study clarified the concepts of structural heterogeneity and redox heterogeneity,and systematically analyzed the mechanisms of heterogeneity governing the transport and transformation of contaminants and remediation reagents.Structural heterogeneity primarily controls contaminant transport and the delivery and dispersion of remediation reagents.Permeability difference within aquifers commonly results in remediation blind zones in low-permeability regions as amendment penetration is limited.This may lead to contaminant rebound during the later stage of remediation due to back diffusion.Redox heterogeneity,characterized by spatial variations in redox capacity,mainly influenced contaminant transformation and remediation reagent consumption through its involvement in electron transfer processes.Consequently,the effects of redox capacity must be explicitly considered in the selection of remediation technologies and the design of operational parameters.Finally,key challenges associated with the remediation of heterogeneous aquifers are identified,and future research directions are proposed based on a synthesis of existing mitigation strategies.
Current understanding remains limited regarding the formation age,petrological composition,genetic mechanisms,and tectonic evolution of the granite encountered in the Baoyunting buried hill within the East China Sea basin.This study presents an integrated zircon U-Pb geochronological and petrogeochemical investigation on granites from two key exploration wells in the Baoyunting area.The objectives are to determine the petrogenesis and deep-seated geodynamic setting of these granites,and to further unravel their formation and evolution processes.Zircon LA-ICP-MS U-Pb dating reveals crystallization ages of 106.9-108.8 Ma for the Baoyunting granites,while the overlying pyroclastic rocks yield younger ages of 35.9-41.3 Ma.The granitic pluton primarily comprises granite and granodiorite,exhibiting geochemical affinities to high-Sr/Y granites or adakitic rocks.Combined petrological and geochemical evidence suggests that the Baoyunting granites originated from partial melting of basaltic rocks within a thickened lower crust during the Early Cretaceous.Integrating the results with regional multidisciplinary data,it proposes that these granites formed in a tectonic setting associated with the Paleo-Pacific Plate slab rollback during the late Early Cretaceous.The evolution of the Baoyunting granite buried hill involved three distinct stages:(1)pluton emplacement,(2)uplift-denudation,and(3)subsidence.
Against the background of low-carbon energy transition,the inherent intermittency and volatility of wind and photovoltaic power pose significant challenges to grid integration and utilization efficiency,which has become a key bottleneck constraining the optimization and upgrading of the energy structure.Energy storage technology,as a core means of achieving inter-temporal energy regulation,provides crucial technical support to address this challenge.As an emerging long-duration,large-scale energy storage technology,deep geothermal energy storage has gradually become a research focus and a frontier direction in the field of renewable energy,owing to its prominent advantages such as substantial scalability,high economical efficiency,wide application scenarios,and strong system resilience.In this paper it systematically elaborates on the technological background and core strengths of deep geothermal energy storage,and conducts an in-depth analysis of the classification characteristics of deep geothermal systems,the geological structures for energy storage,as well as the key factors influencing storage capacity and efficiency.It presents a detailed review of mainstream technical pathways,including hydrothermal reservoir heat storage,geotechnical energy storage,compressed air energy storage,and CO2 plume geothermal systems,covering their working principles,current status of engineering applications,and key technological advances.The paper comprehensively examines the critical issues currently faced by deep geothermal energy storage in areas such as site exploration,efficiency regulation,and environmental safety risk prevention.Finally,future development recommendations are proposed from two dimensions:the construction of a multi-energy complementary energy system,and the enhancement of technological innovation and industrial development systems.The aim is to provide theoretical reference and technical support for the large-scale application and sustainable development of deep geothermal energy storage technology,thereby contributing to the achievement of China's"dual-carbon"goals and energy security strategy.
The Xihu Depression underwent significant tectonic inversion during the Miocene,underscoring the importance of elucidating its coupling effects with hydrocarbon accumulation.This study utilizes various data,including 3D seismic,well logging,and employs multiple methods for a quantitative assessment of tectonic inversion intensity.The results indicate that the depression-uplift transition in the central anticline zone is pronounced,featuring the development of near EW extensional normal faults in the shallow anticline core,while early NNE-NE trending normal faults underwent activation through compressional inversion.Based on the characteristics of inversion normal faults,eight types of inverted structural styles have been classified.Through quantitative evaluations using fold amplitude ratios,fracture fractals,and fault inversion rates,it established that the central anticline belt exhibits a north-strong and south-weak pattern of tectonic inversion intensity,based on which four characteristic hydrocarbon accumulation models were established:Type I:fault-sand coupling under weak structural inversion;Type II:deep localized enrichment driven by intensive structural adjustment under moderate-to-strong inversion;Type III:vertical multi-stratigraphic enrichment facilitated by relay-style faulting under strong inversion;Type IV:large-scale enrichment preserved by non-penetrating faults under strong tectonic inversion.This research enhances the understanding of hydrocarbon accumulation mechanisms within the context of tectonic inversion in the Xihu Depression and provides valuable insights for exploration in analogous basins.
Sliding directional drilling is widely used in directional boreholes for tasks such as advance probing,detection of abnormal bodies related to geological hazards,and gas drainage,helping improve geological interpretation and drilling efficiency.This paper addresses the problem of reduced trajectory tracking accuracy caused by complex formation disturbances during sliding directional drilling,and proposes an extended-state-observer-based model predictive control method for trajectory tracking.First,the kinematic behavior of the drilling tool is analyzed and a trajectory extension model for sliding drilling is built.Based on this model,a trajectory prediction model is constructed,and an objective function that minimizes trajectory error is designed to develop the MPC controller.Then,to reduce steady tracking errors caused by formation disturbances,an extended state observer with disturbance estimation is designed to compensate the control input.Simulation results show that the proposed provides disturbance compensation,high tracking accuracy,and strong robustness,with practical value for improving exploration efficiency and reducing designed to operational risk.
To explore the relationships among mineral distribution in sediments,their reducing capacity,and the abiotic reduction rate of organic pollutants in groundwater,this study utilized two sets of typical columnar sediment cores.A systematic investigation of sediments was conducted,including particle size composition,mineral distribution,iron speciation,electron-donating capacity(EDC),and abiotic reduction rate of nitrobenzene induced by sediment.Results show that the predominant minerals in sediments varied with sediment particle size,with clay minerals such as illite primarily concentrated in the clay fractions.Clay fractions exhibited a higher EDC than silt fractions,and presented a faster abiotic reduction rate for nitrobenzene.Moreover,EDC not only can serve as a quantitative measure of sediment reducing capacity,but also can act as a valuable indicator for assessing the potential for abiotic reduction of nitrobenzene by sediments.These findings provide a new perspective for predicting the abiotic natural reduction capacity of sediments and groundwater organic contaminant remediation.
This study systematically analyzes the control of detachment layer distribution on structural style differences and trap-hydrocarbon generation coupling relationships in the frontal tectonic triangle zone of the Western Kunlun Mountains,based on seismic and drilling data.It is found that the evolution of the piggyback basin in the Upal section of the West Kunlun Mountains began with fault-bend folding controlled by Carboniferous-Permian and Paleogene detachment layers.Subsequently,the thrust in the fold core experienced intense uplift,ultimately leading to flexural subsidence due to rock gravity loading,completing a three-stage evolution process.The Sugaite-Qimugen-Kedong section,influenced by multiple detachment layers in the middle crust,Cambrian,and Carboniferous-Permian systems,develops imbricate thrust belts and frontal single-thrust zone.The former is dominated by Neogene-formed unsaturated hydrocarbon reservoirs,while the latter inherits Triassic structures with well-preserved traps,becoming a favorable area for Cretaceous hydrocarbon accumulation.At the endpoints of the tectonic wedge,intense erosion of source rocks generally results in a lack of effective hydrocarbon charging.The Duwa-Wujiate section only develops a Cambrian detachment surface,indicated by large-scale fault-bend folding and a lack Carboniferous-Permian source rocks.This study clarifies the critical role of detachment layers in controlling structural evolution and hydrocarbon distribution.
The basin-mountain coupling theory has been widely recognized.However,it remains controversial in its interpretation for the basin-mountain systems in extensional regime.To unravel the basin-mountain coupling relationships under extensional regime,this study integrates field outcrops,borehole and seismic data,and geochemical and thermochronological data from the Jianghan basin and surrounding mountains,systematically clarifying their tectonic evolution.The surrounding mountains successively experienced rapid cooling,continued cooling,slow cooling and rapid cooling stages,and the Jianghan basin accordingly experienced compressional deformation,thermal doming,rifting and subsidence,and post-rift evolution.The upwelling of asthenospheric mantle not only drove the basin to undergo rifting and subsidence,but also delivered a large amount of deep composite materials to the basin.Our study proposes that the Jianghan basin became progressively deeper during the formation of the basin-mountain system,while the surrounding mountains got progressively lower and lower.The influence between the Jianghan basin and surrounding mountains is multi-faceted and single-directional.Their coupling model can be summarized as follows:(1)surrounding mountains shape the basin;(2)mountain exhumation results in basin filling;(3)the basin with increasing heat input transfers heat to surrounding mountains.
