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.

 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 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.

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.