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The mechanical behaviour of natural, unfilled rock joints is influenced by the interaction between surface roughness and matedness of the contact surfaces. In the field, natural rock joints normally exhibit a mismatch between the contact surfaces, mainly due to different geological processes such as weathering or deformations. Various attempts have been made to estimate how matedness of rock joints influences their peak shear strength. However, the proposed methodologies imply certain difficulties since they are intended to estimate the matedness of rock joints based mainly on visual inspection, and by relating an initial shear displacement to the length of the analysed sample or by relating the opening of saw-tooth and two-dimensional joint profiles with the degree of interlocking. Therefore, a tested peak shear strength criterion for natural, unfilled rock joints that realistically accounts for the influence of matedness on their peak shear strength is still lacking. This paper presents a methodology where objective measurements of the average aperture of natural, unfilled rock joints are used to estimate their matedness as a step in the prediction of the peak shear strength. This measured average aperture is based on high-resolution optical scanning of the surface roughness. The proposed relationship between measured average aperture and matedness of natural rock joints has been included in a further developed peak shear strength criterion. The verification against ten natural rock joint samples of coarse-grained granite showed that the revised criterion can predict the peak shear strength considering rock joint matedness.

This study investigates the trends and processes of flooding in Kota Belud, Sabah, Malaysia, following the 2015 Ranau Earthquake. The earthquake caused landslides that altered river systems and significantly impacted flood patterns. Using an interdisciplinary methodology, we examined geological processes, river morphology, sediment dynamics, and erosion mechanisms to understand the correlation between geological forces and flooding. The investigation spanned a decade (2010-2020), revealing an increase in flood incidents post-earthquake. Key findings include the impact of sediment dynamics on river behavior, the role of river morphology, and the importance of erosion and sedimentation in flood timing. This research offers valuable insights into disaster management strategies, emphasizing the need for understanding geological influences on flood susceptibility.

Banded iron-formations (BIFs) are marine chemical sedimentary rocks composed of siliceous and ferric materials, usually with typical thin layers or sheet structures. BIFs not only record a wealth of information about the state and evolution of the lithosphere, atmosphere, hydrosphere, and biosphere but also host the majority of the economic iron resources in the world. Here, we summarize the types, mineralogical, and geochemical characteristics of BIFs; analyze their formation conditions, their oxidative mechanism, and the absence causes of BIFs; and elucidate the associations between BIFs and major atmospheric oxidation events (Paleoproterozoic great oxidation event (2.4~2.1 Ga) and Neoproterozoic oxidation event (0.8~0.55 Ga)). BIFs are intimately associated with enhanced submarine magmatic–hydrothermal activities. Finally, it is concluded that the deposition and demise of BIFs are closely related to major geological events, and these major geological events interact with each other, jointly constraining the evolution of the atmospheric and marine environment and of geo-biological and geodynamic processes.

The Qigebulake Formation in the northwestern Tarim Basin records high-frequency oolitic tidal flat cycles formed during the Upper Ediacaran, a period marked by tectonic, volcanic, and hydrothermal events. This study presents a detailed petrographic and geochemical characterization of these cycles, focusing on their lithofacies development and implications for regional geological processes. Seven microfacies were identified, ranging from oolitic dolostone and dolothrombolite to siliciclastic dolomudstone and mudstone. Elemental trends indicate a systematic decline in SiO2, Al2O3, and TiO2 content with decreasing siliciclastic input, suggesting a shallowing-upward sequence. Volcaniclastic quartz grains, exhibiting embayed textures and bright-blue cathodoluminescence, are reported here for the first time in the Ediacaran of Tarim, supporting synsedimentary volcanic input. Positive δEu anomalies, coupled with low Al/(Al+Fe+Mn) and elevated Fe2O3/TiO2 and MnO/TiO2 ratios, reveal hydrothermal influence in upper-cycle dolostones. These signatures, combined with regional stratigraphy, suggest that the Qigebulake tidal flat records the interplay between deposition, volcanism, and fluid migration during the late Ediacaran. The findings provide new constraints on the evolution of peritidal environments and inform deep carbonate reservoir assessments in Tarim and similar cratonic basins.

The present paper addresses methods for formalization of engineering geological complexity of urban territory based on engineering geological zoning for purposes of urban and spatial planning. Presented is distinguishing three main sets of issues for purposes of urban development complex, improvement of environmental management and assessment of engineering geological complexity distribution, issues being addressed at two levels: at the city level--mapping the engineering geological complexity to scale of 1: 100000 and at municipal level--engineering geological complexity maps to scale of 1: 25000 with derivation of taxonomic formula of geological hazard; at that, cartographical materials are proposed as open data. For the first time it is proposed to use the complexity index and to plot the diversity curves for negative geological processes. Results of distribution analysis for complexity of engineering geological conditions made it possible to reveal a relatively low complexity of the structural uplift megamassif at the territory of the city of Moscow. The proposed methods shall help to develop \"geoecological image\" of the city and be used for better understanding of geoecological problems related to the city development.

The study object of this work is the soils of the Priolkhonye mountain-steppe landscapes. This research is performed at the Priolkhonye test site. Annual monitoring for exogenous geological process activity is conducted there. This research aims to study the influence of gravitational geological processes (landslides) on the migration of heavy metals, which are introduced into soil as a result of human agricultural activity. A methodology for the geoecological monitoring of soils based on an assessment of their contamination level by anthropogenic heavy metals, and a transfer mechanism throughout whole migration path (field–landslide–coast) is proposed. The following steps were taken to solve this problem: isolating a fine-grained fraction (<100 μm); determining the Hg, Cd, Pb, and Cu concentrations using wavelength dispersive X-ray fluorescence and atomic absorption spectroscopies, as well as total organic carbon (TOC) content using UV-Vis spectrophotometry; computing various geochemical indices; and describing the migration path of these heavy metals and TOC. The monitoring results showed that these pollutants migrate to the coastal zone as a result of landslides activation. The soil contamination level is increased which can cause negative toxic effects in coastal ecosystems, and could rise to a dangerous level for humans. Thus, the observed changes in the indices and TOC values allow us to assess the geoecological state of the study area; namely, the periods of landslide activity and the supply of these pollutants to the coastal zone.

Underground coal mining often causes subsidence, goaf landslides, fissures, and even hazard chains, seriously damaging the ecological environment. To address the ecological vulnerability of mining areas is key to exploring the development characteristics and failure mechanisms of surface multi-hazards. Taking the Shuiliandong coal mine as an example, the mine deformation area was identified using differential interferometric synthetic aperture radar (D-InSAR) technology. We found that the spatial evolution of the deformation areas was controlled by the mining sequence. The impacts on the surface deformation and the mining-induced landslide were continuous and long term. Thus, the surface fissures and landslide were characterized using historical images. The fissures were clustered and short, and there was a negative exponential relationship between the length and the cumulative number of fissures. The fissure density decreased with increasing distance from the mine tunnel. In addition, the particle flow numerical simulation analysis method was used to simulate the subsidence-fissure-landslide hazard chain process. Three distinct stages were identified: initial stage, rapid development stage, and creep stage. The displacements at the different monitoring points exhibited a distinct S shape. The cumulative number of fissures developed same as the subsidence and landslide, exhibiting an S shape. The fissures played an important role in the hazard chain, accelerating the subsidence and landslide processes.

In modern conditions, modelling of production processes in various industries is not only a highly effective means of planning and visualizing the activities of an enterprise, but also an urgent scientific task. Modern modelling tools allow a wide range of scientific and applied research to be carried out to help plan the activities of the enterprise and identify new ways to gain competitive advantage. The modelling process itself is performed in specialized software packages with a wide range of capabilities.

Although biodiversity and ecosystem functions are strongly shaped by contemporary environments, such as climate and local biotic and abiotic attributes, relatively little is known about how they depend on long-term geological processes. Here, along a 3000-m elevational gradient with tectonic faults on the Tibetan Plateau (that is, Galongla Mountain in Medog County, China), we study the joint effects of geological and contemporary environments on biological communities, such as the diversity and community composition of plants and soil bacteria, and ecosystem functions. We find that these biological communities and ecosystem functions generally show consistent elevational breakpoints at 2000–2800 m, which coincide with Indus-Yalu suture zone fault and are similar to the elevational breakpoints of soil bacteria on another mountain range 1000 km away. Mean annual temperature, soil pH and moisture are the primary contemporary determinants of biodiversity and ecosystem functions, which support previous findings. However, compared with the models excluding geological processes, inclusion of geological effects, such as parent rock and weathering, increases 67.9 and 35.9% of the explained variations in plant and bacterial communities, respectively. Such inclusion increases 27.6% of the explained variations in ecosystem functions. The geological processes thus provide additional links to ecosystem properties, which are prominent but show divergent effects on biodiversity and ecosystem functions: parent rock and weathering exert considerable direct effects on biodiversity, whereas indirectly influence ecosystem functions via interactions with biodiversity and contemporary environments. Thus, the integration of geological processes with environmental gradients could enhance our understanding of biodiversity and, ultimately, ecosystem functioning across different climatic zones.

It is of great significance to apply the object detection methods to automatically detect boulders from planetary images and analyze their distribution. This contributes to the selection of candidate landing sites and the understanding of the geological processes. This paper improves the state-of-the-art object detection method of YOLOv5 with attention mechanism and designs a pyramid based approach to detect boulders from planetary images. A new feature fusion layer has been designed to capture more shallow features of the small boulders. The attention modules implemented by combining the convolutional block attention module (CBAM) and efficient channel attention network (ECA-Net) are also added into YOLOv5 to highlight the information that contribute to boulder detection. Based on the Pascal Visual Object Classes 2007 (VOC2007) dataset which is widely used for object detection evaluations and the boulder dataset that we constructed from the images of Bennu asteroid, the evaluation results have shown that the improvements have increased the performance of YOLOv5 by 3.4% in precision. With the improved YOLOv5 detection method, the pyramid based approach extracts several layers of images with different resolutions from the large planetary images and detects boulders of different scales from different layers. We have also applied the proposed approach to detect the boulders on Bennu asteroid. The distribution of the boulders on Bennu asteroid has been analyzed and presented.