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This study selects geochemical data of basalts from different seamounts in the Mid-Pacific Mountains province and conducts analyses of major and trace elements as well as Sr-Nd-Pb isotopes to explore the tectonic evolution, petrogenesis, and mantle-source magama characteristics of the Mid-Pacific Mountains. The basalts from the Mid-Pacific Mountains are predominantly alkali basalts, rich in alkalies, and changing in potassium. They exhibit geochemical features of ocean island basalts (OIB), with distinct fractionation between light and heavy rare-earth elements and a pronounced Ce negative anomaly (δCe = 0.16–1.10, average 0.84), along with enrichment in large ion lithophile elements (LILEs). The Mid-Pacific Mountains are intraplate ocean island basalts formed by mantle plume (hotspot) activity, originating mainly from an enriched mantle magma source region, and most of them have undergone low degree of partial melting and a certain degree of crystalline differentiation, with negligible contamination from oceanic crust materials. The Mid-Pacific Mountains exhibit ratios of 87Sr/86Sr(i) (0.702 733–0.704 313, average 0.703 452) and 143Nd/144Nd(i) (0.512 698–0.512 996, average 0.512846) which are close to the HIMU mantle end member, and ratios of 206Pb/204Pb (18.953–19.803), 207Pb/204Pb (15.54–15.62) and 208Pb/204Pb (38.813–39.514) which are close to the EMII mantle end-member. Combined with the isotopic geochemical characteristics in the West Pacific Seamounts province, the basalts from the Mid-Pacific Mountains were considered to represent a certain proportion of mixing mantle end-members between the HIMU and EMII, possibly formed by the mixing of the HIMU superplume in the South Pacific hotspot region with the EMII secondary mantle plume in the transition zone during their ascent.

The lower member of Dalazi Formation is an important oil reservoir in the Songjiang Basin. Based on the research on its field-measured geological profiles, lithological combination characteristics and grain size distribution characteristics, combined with the analysis of the spatial distribution characteristics, sedimentary structural characteristics and hydrodynamic conditions of the sediments in this member, nine sedimentary microfacies of the fan delta plain subfacies, fan delta front subfacies and littoral-shallow lacustrine subfacies have been identified.The study reveals that lower member of Dalazi Formation in the research area follows a fan delta–shallow lacustrine depositional model in the steep slope zone of a rift lake basin. The sediments primarily originate from the Pre-Mesozoic strata in the steep southeastern and eastern margins. The basin center migrated from the early Xiaoshahe area to the Yangmucun–Shenglicun area, and the sedimentary system gradually transitioned from fan delta to littoral-shallow lacustrine facies.

 The pore structure of rocks significantly influences the porosity and permeability of reservoirs and the migration ability of oil and gas, and being the key task on the development of volcanic gas reservoirs. Nine volcanic rock samples from the Yingcheng Formation and Huoshiling Formation in the Longfengshan area of the Changling Fault Depression in the Songliao Basin were selected for this study. The pore structures of the volcanic rocks in the study area were investigated using high-pressure mercury injection, X-ray diffraction combined with fractal theory. The relationships between the fractal dimension and physical properties characteristics, pore structure parameters, and mineral content were analyzed to provide guidance for the development of volcanic rock gas reservoirs. The results show that the reservoir can be divided into 3 types (I, II, and III) based on the shape of the capillary pressure curve, and the physical properties deteriorate successively. Different types of reservoirs exhibit different fractal characteristics. For types I, II and III, the average total fractal dimensions were 2.3418, 2.6850, and 2.9203, respectively. The larger the fractal dimension, the stronger the heterogeneity of reservoir. A small number of macro-pores primarily contributed to permeability. The fractal dimension was negatively correlated with porosity and permeability. The fractal dimension of the rock was strongly correlated with quartz and feldspar contents, and the mineral composition and content are closely related to the pore evolution of the reservoir, which are the internal factors affecting the fractal dimension of volcanic rock.

To investigate the Early Cretaceous magmatic activity and tectonic evolution in the Xiaoqinggou mining area of Jilin Province, the authors conducted petrological, geochemical, and isotopic analyses of diorite rocks. The findings show that the zircons exhibit distinct magmatic growth zoning, confirming their magmatic origin. LA–ICP–MS zircon U–Pb dating yielded an age of 128.7±2.2 Ma, corresponding to Early Cretaceous. Geochemical data reveal that the diorite rocks are high and potassium but low in sodium, classifying them within the peraluminous, high-potassium calc-alkaline series. They are enriched in large ion lithophile elements (e.g., K, Ba and Rb) and depleted in high field strength elements (e.g., Nb, Ta and Ti). The δEu values range from 1.07 to 1.14, indicating weakly positive Eu anomalies. Regional comparisons and integrated studies suggest that the Xiaoqinggou diorite rocks formed in a volcanic island arc setting, associated with the westward subduction of the Paleo-Pacific plate beneath the Eurasian continent in an extensional tectonic environment. This study provides a theoretical basis for further exploration of the Xiaoqinggou deposit.

 Recurring Slope Lineae (RSL) are seasonally observed dark streaks on the Martian surface that exhibit distinct spatial and temporal distribution characteristics. Exploring their formation mechanisms can deepen our understanding of surface activity on Mars and provide scientific basis for future Mars exploration. This study aims to gain a comprehensive understanding of the spatial and temporal distribution characteristics and formation mechanisms of RSL by reviewing relevant literature and synthesizing various viewpoints and experimental results. RSL typically appear during warm seasons, disappear during cold seasons, and repeat over multiple Martian years. The formation mechanisms can be broadly categorized into three types: dry mode, wet mode, and mixed mode. However, a definitive explanation for the formation of RSL is still lacking, and both the dry and wet models have their respective limitations. It is likely that the formation of RSL is the result of the combined action of multiple mechanisms. The next step should be to search for terrestrial analogs of RSL and conduct research at high spatial and temporal resolutions to understand the forming processes of RSL.

Groundwater overexploitation is the main cause of city surface deformation. In Siping City, groundwater level had decreased since 1980 due to large-scale exploitation of groundwater. Subsequently, the level began to rise under governance while shown a declining trend in the whole Siping area. This paper obtained surface deformation of Siping City from 2017 to 2024 using 36 Sentinel-1B satellite images and 88 Sentinel-1A satellite images based on SBAS-InSAR and analysed the effect of groundwater on deformation. The results indicated that uplift occurs in the centre of the urban area with a maximum average velocity of about 5 mm/y and there were two main subsidence zones during these two time periods with average subsidence velocities of about 3 mm/y and 1.7 mm/y. Groundwater levels showed a high correlation with surface deformation, with rising the levels leading to surface uplift and falling the levels leading to surface subsidence.

There is an issue of groundwater overexploitation in Ningjiang District, Songyuan City, Jilin Province, which has led to land subsidence. To investigate the influence of hydrological elements on surface deformation in Ningjiang District, surface deformation data were obtained by the small baseline subset interferometry synthetic aperture radar (SBAS-InSAR) technique. Initially, Sentinel-1B data were utilized to observe surface deformation in Ningjiang District from 2017 to 2021 with SBAS-InSAR. Subsequently, the geographical detector was employed to quantitatively assess the relationship between land subsidence and its influencing factors. Furthermore, multivariate singular spectrum analysis (M-SSA) was employed to identify periodic fluctuations in surface deformation and groundwater level, revealing the temporal lag between f luctuations in surface deformation and groundwater level. The findings demonstrate that the distance to water bodies accounts for the largest share of subsidence variation, with subsidence shaped by the combined impact of many factors. The results of interaction detection indicate that the interplay between the distance to water bodies and precipitation exhibits the most significant joint explanatory capacity for surface deformation. The observed seasonal cyclical fluctuations in groundwater level and surface deformation indicate a substantial influence of groundwater on surface deformation in the Ningjiang District.

 Evaluation of backfilling effectiveness plays a crucial role in the geological environment management and restoration of abandoned open-pit quarries, providing a scientific basis for subsequent greening efforts. Backfill soil, predominantly composed of silty clay, demonstrates high water retention capacity and elevated moisture content, leading to a pronounced resistivity contrast with the bedrock exposed by quarrying activities. To investigate the distribution of backfill soil subsurface and assess backfilling effectiveness in the study area, this study conducted a comprehensive geophysical investigation utilizing the high-density electrical resistivity tomography (ERT). A total of 19 ERT survey lines were deployed across three distinct areas in Liuyao Village, Huaibei City, Anhui Province, China. The inversion results, derived from both two-dimensional (2D) and three-dimensional (3D), reveal distinct electrical properties of the subsurface materials: the backfill soil layer shows low resistivity features, the fill stone layer exhibits medium to high resistivity, and the bedrock shows the highest resistivity. The 2D inversion results, from the data measured using the Wenner array effectively capture the spatial distribution and structural features of the backfill soil layer. The findings indicate a gradual east-west thinning of the clay layer within the quarry. Furthermore, the northern pit area exhibits a uniform distribution of backfill soil layer, indicative of effective backfilling operations. In contrast, the southern pit area lacks a well-defined clay layer, suggesting suboptimal backfilling effectiveness.

The large-scale acquisition and widespread application of remote sensing image data have led to increasingly severe challenges in information security and privacy protection during transmission and storage. Urban remote sensing image, characterized by complex content and well-defined structures, are particularly vulnerable to malicious attacks and information leakage. To address this issue, the author proposes an encryption method based on the enhanced single-neuron dynamical system (ESNDS). ESNDS generates high quality pseudo-random sequences with complex dynamics and intense sensitivity to initial conditions, which drive a structure of multi-stage cipher comprising permutation, ring-wise diffusion, and mask perturbation. Using representative GF-2 Panchromatic and Multispectral Scanner (PMS) urban scenes, the author conducts systematic evaluations in terms of inter-pixel correlation, information entropy, histogram uniformity, and number of pixel change rate (NPCR)/unified average changing intensity (UACI). The results demonstrate that the proposed scheme effectively resists statistical analysis, differential attacks, and known-plaintext attacks while maintaining competitive computational efficiency for high-resolution urban image. In addition, the cipher is lightweight and hardware-friendly, integrates readily with on-board and ground processing, and thus offers tangible engineering utility for real-time, large-volume remote-sensing data protection.

The Longfengshan structural belt lies in the southern Changling Depression. The Yingcheng Formation is the primary gas-bearing unit. The Yingcheng Formation has low permeability and contains deep, tight gas that is challenging to extract. Industrial gas flow has been achieved from the B218 and B220 well blocks in the sandstone layer of the first member of Yingcheng Formation (Ying I), indicating the potential of this sandstone group for gas production. Although oil and gas are widely distributed in the Ying I sandstone layer, production capacity varies significantly across the formation. into six sublayers. Drilling, logging, and laboratory testing data were integrated to subdivide the Ying I sandstone layer into six sublayers. Core and well logging analyses indicate a braided river delta depositional environment. Data and seismic inversion identify the Ying I-5 sublayer as the primary exploration target. The effective reservoir in the eastern fan body, where porosity ranges from 5% to 13% and maximum effective thickness reaches 34 m. This study basis for optimizing well placement and estimating gas reserve parameters in the Ying I sandstone layer of the Longfengshan area. The findings can guide the development of other tight gas reservoirs.

 The detection of unexploded ordnance (UXO) is critical for battlefield clearance and civilian safety. This study presents the development of a software for automated simulation based on the high frequency structure simulator (HFSS) and the MATLAB application programming interface (API), which together form the HFSS-MATLAB-API. This interface enables control over HFSS and conducts frequency-domain electromagnetic simulations for various types of UXO, including anti-tank mines, grenades, mortars, and aerial bombs. The software automates modelling, solving, data extraction, and analysis through MATLAB, enhancing the efficiency of simulation and enabling flexible settings for target models, coil parameters, and subsurface media. The research utilizes numerical simulation methods to analyze the response characteristics of different types of UXO in electromagnetic induction and explores the impact of the rotation angle of the target model on the attenuation characteristics of the measurement line. The results indicate that the electromagnetic response of UXO varies significantly based on type, burial depth, and spatial orientation. The findings provide a theoretical foundation for the electromagnetic detection, target identification, and classification of UXO.

Slope units are divided according to the real topography and have clear geological characteristics, making them ideal units for evaluating the susceptibility to geological disasters. Based on the results of automatically and manually corrected hydrological slope unit division,the Longhua District, Shenzhen City, Guangdong Province, was selected as the study area. A total of 15 influencing factors,namely Fluctuation,slope, slope aspect, curvature, topographic witness index (TWI),stream power index (SPI),topographic roughness index (TRI), annual average rainfall,distance to water system, engineering rock group,distance to fault, land use,normalized difference vegetation index (NDVI),nighttime light, and distance to road, were selected as evaluation indicators. The information volume model (IV) and random points were used to select non-geological disaster units, and then the random forest model (RF) was used to evaluate the susceptibility to geological disasters. The automatic slope unit and the hydrological slope unit were compared and analyzed in the random forest and information volume random forest models. The results show that the area under the curve (AUC) values of the automatic slope unit evaluation results are 0.931 for the IV-RF model and 0.716 for the RF model, which are 0.6% (IV-RF model) and 1.9% (RF model) higher than those for the hydrological slope unit. Based on a comparison of the evaluation methods based on the two types of slope units, the hydrological slope unit evaluation method based on manual correction is highly subjective, is complicated to operate,and has a low evaluation accuracy, whereas the evaluation method based on automatic slope unit division is efficient and accurate, is suitable for large-scale efficient geological disaster evaluation, and can better deal with the problem of geological disaster susceptibility evaluation.

Five new small theropod teeth and one manual ungual have recently been recovered from the Upper Cretaceous Nenjiang Formation in the Songliao Basin. The specimens were examined for their morphological characteristics, leading to the identification of four distinct taxa. The first taxon consists of three foliodont teeth characterized by a pronounced basal constriction and large hook-like distal denticles, which can be attributed to Troodontidae. The second taxon is represented by an elongated tooth featuring prominent longitudinal ridges, allowing for its assignment to Paronychodon. The third taxon is a bladelike tooth with notably small distal denticles, corresponding to Richardoestesia. The fourth taxon comprises a manual ungual characterized by a transversely wide and nearly symmetrical proximal articular surface, fully enclosed ventral foramina, a flattened ventral surface, and the absence of a flexor tubercle, resembling Alvarezsauridae. These specimens significantly enhance the known dinosaur diversity of the Nenjiang Formation and provide crucial insights for understanding the terrestrial ecosystem in Northeast Asia during the Late Cretaceous.

The Solonker Suture records the termination of the Central Asian Orogenic Belt (CAOB), but its eastward extension beneath the Songliao Basin has not been clear. The Yaduwula ophiolite is one of the significant fragments within the Solonker Suture. LA–ICP–MS U–Pb dating of zircon grains from metamorphic basalts yield ages of 263±4 Ma and 274±3 Ma, constraining the Yaduwula ophiolite in the late Cisuralian and Guadalupian age. This might indicate that the subduction of Paleo-Asian Ocean continued until at least the Guadalupian (middle Permian). Geochemical analysis of the metamorphic basalts revealed enrichment in large ion lithophile elements (LILEs) and depletion in high field strength elements (HFSEs) and show the characteristics of a supra-subduction zone. The results provide the evidence for the closure time of the Paleo-Asian Ocean after the middle Permian and also suggest that the Yaduwula ophiolite may be considered the eastern extension of Solonker Suture. Our study provides further insights on the evolution of the southeastern Central Asian Orogenic Belt.

The Mailong gold deposit is located in the eastern section of the East Kunlun orogenic belt and is one of the recently discovered important gold polymetallic deposits in the Qinhai Gouli region. The primary host rocks of the Mailong gold deposit consist of intermediate-acid intrusive rocks from the Varisian and Indosinian periods, as well as the Precambrian Jinshuikou Group, with mineralization controlled by northeast and northwest faults. The alteration of the host rocks is mainly characterized by silicification, sericitization, chloritization, and carbonatization. Based on the cross-cutting relationships of the veins, the hydrothermal mineralization of the gold deposit can be categorized into three stages: the quartz-pyrite stage, the quartzpolymetallic sulfide stage, and the quartz-carbonate stage. Microthermometry of fluid inclusions indicates that the Mailong gold deposit belongs to a low-density (0.73–0.86 g/cm3 ), medium-temperature (240–340 ℃), and medium-salinity (4.01–10.74 wt% NaCl) NaCl-CO2-H2O fluid system. The C-H-O isotopic analysis suggests that the mineralizing fluids is derived from magmatic water, with later contributions from atmospheric precipitation. In-situ S isotopic results indicate that the mineralizing materials mainly derive from igneous rocks. A comprehensive analysis concludes that the Mailong gold deposit is a mesothermal hydrothermal vein-type gold deposit controlled by structural factors.

Previous studies have shown that the Eocene oil shale sequences in the Green River Basin contain long-period astronomical age information. The fine-scale chronological characteristics of the oil shale laminae remain largely unexplored.We selected finely laminated oil shales formed in deep-water environments characterized by stable water column stratification as the primary focus of this study, using microscopy and micro-area X-ray fluorescence (μ-XRF) techniques. By integrating high-resolution elemental data with timeseries analysis, we identified significant periodic signals associated with solar activity (Hale and Schwabe cycles) and ENSO. The results indicate that the alternations of light and dark laminae in the Green River Formation oil shale correspond to alternating dry and wet climate regimes: the light laminae are dominated by carbonate minerals, reflecting drier and milder conditions, while the dark laminae are enriched in terrigenous clastics and organic matter, indicating periods of increased precipitation and warmer temperatures. The detected periodicities (23.5 years, 13.3 years and 5.8 years) are highly consistent with modern observations, demonstrating that the lower Eocene Green River oil shale effectively records short-term solar activity and climate variability. Furthermore, our findings confirm that a persistent "permanent El Niño" state did not develop under Early Eocene greenhouse conditions, providing a refined chronological framework for highresolution paleoclimate studies during greenhouse intervals.

In recent years, significant breakthroughs have been achieved in the exploration of deep volcanic rocks in the Junggar Basin, highlighting their substantial exploration potential. The complex distribution of volcanic reservoirs is attributed to the multi-phase tectonic evolution within the basin, with their superior reservoir properties playing a crucial role in natural gas formation. However, due to the combined effects of multi-cyclic volcanic eruptions and tectonic activities, predicting volcanic facies distribution and favorable reservoirs remains highly challenging. This study focuses on the third member of the Jiamuhe Formation in the Zhongguai Uplift. By integrating drilling and petrophysical data with well-seismic analysis techniques, a seismic identification model for volcanic reservoirs has been established. The findings reveal that different facies exhibit distinct seismic response characteristics. Andesite, rhyolite, volcanic breccia, and volcanic clastic rocks show variability in amplitude, frequency, and continuity. Using structural-guided filtering, high-resolution coherence analysis, and 3D body carving techniques, the locations of volcanic craters and eruption centers were successfully identified, further clarifying the distribution patterns of volcanic facies. By combining multi-attribute clustering analysis and seismic attribute extraction, a volcanic facies zone distribution map was generated, and favorable exploration directions for volcanic reservoirs were proposed. The study provides technical guidance for the exploration of deep volcanic oil and gas reservoirs in the Junggar Basin and holds significant application value.

The Jiao-Liao-Ji Belt within the North China Craton had undergone a complex tectonic evolution, marked by extensive Paleoproterozoic magmatism that produced a diverse range of mafic to felsic magmatic rocks. These events provide valuable geological records for understanding the tectonic evolution of the Jiao-Liao-Ji Belt. This study focuses on the Paleoproterozoic Chibaisong meta-gabbro in southern Jilin, investigating the source of mafic magma, petrogenesis, and tectonic setting through systematic petrological analysis, zircon U-Pb dating, and geochemical studies. The findings contribute to constraining the dynamic mechanisms of Paleoproterozoic extensional rifting in the Jiao-Liao-Ji orogenic belt. Geochemical data indicate that the samples exhibit low SiO₂(47.99–50.66 wt.%), TiO₂(0.75–3.20 wt.%), Nb(3.22–8.09 ppm), and Ta(0.22–0.51 ppm) contents, along with high TFeO₃(11.97–15.82 wt.%) and MgO(5.67–12.66 wt.%) concentrations. They also show low Nb/La ratios and high (Th/Nb)N values, consistent with the geochemical characteristics of tholeiitic basalts. The samples display low total rare earth element concentrations, weak or absent Eu anomalies, slight enrichment in light rare earth elements, relatively flat heavy rare earth element patterns, and depletion in Nb, Ta, and Ti. The meta-gabbro from southern Jilin exhibits geochemical similarities to Paleoproterozoic metamafic rocks from other regions of the Jiao-Liao-Ji Belt, resembling enriched mid-ocean ridge basalts (E-MORB) with Nb, Ta, and Ti depletion. Integration of previous studies and geochemical data suggests that the 2.16–2.10 Ga metamafic rocks in the Jiao-Liao-Ji Belt experienced contamination by older crustal material. These results indicate that the 2.16–2.10 Ga metamafic rocks are unlikely to be associated with island arc, continental arc, or mid-ocean ridge settings. Instead, they are more likely related to intraplate magmatism associated with continental rifting