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Global climate change and permafrost degradation have significantly heightened the risk of geological hazards in high-altitude cold regions, resulting in severe casualties and property damage, particularly in the Qinghai-Tibet Plateau of China. To mitigate the risk of geological disasters, it is crucial to identify the primary disaster-inducing factors. Therefore, to address this issue more effectively, this study proposes a spatiotemporal-scale approach for detecting disaster-inducing factors and investigates the disaster-inducing factors of geological hazards in high-altitude cold regions, using the Kanchenjunga Basin as a case study. As the world's third-highest peak, Kanchenjunga is highly sensitive to climate fluctuations. This study first integrates the frost heave model and multitemporal interferometric synthetic aperture radar techniques to monitor ascending and descending track line-of-sight deformation of the frozen active layer in the study area. Subsequently, the surface parallel flow constrained model is employed to decompose the 3-D time-series deformation of geological hazards in the basin, with remote sensing imagery and field surveys used to identify a total of 94 disaster sites. In parallel, a database of potential conditioning factors is constructed by leveraging Google Earth Engine remote sensing inversion technology and relevant data provided by the China Geological Survey. Finally, by integrating monitoring results with a database of potential geological conditioning factors, the spatiotemporal-scale approach for detecting disaster-inducing factors proposed in this study is applied to investigate the disaster-inducing factors in the Kanchenjunga Basin. The research results highlight that surface temperature is the primary driving factor of geological hazards in the Kanchenjunga Basin. This research helps bridge the data gap in the region and offers critical support for local government decision-making in disaster prevention, risk assessment, and related areas.

期刊论文 2025-01-01 DOI: 10.1109/JSTARS.2025.3569666 ISSN: 1939-1404

Lunar volcanic volatiles are crucial for understanding eruption dynamics on the Moon as well as the potential formation, life span, and dissipation of a lunar secondary atmosphere. We review literature concerning volatile content, degassing extent, and speciation during the mare eruption period on the Moon from 4.0 to 1.2 Ga, providing a realistic summary of degassed compositions for the traditional volcanic elements C-O-H-S-F-Cl. The most reliable estimates of lunar volcanic volatiles come from high-titanium (high-Ti) glass beads sampled during the Apollo 17 mission. Analysis of these samples demonstrates that hydrogen is the most abundant element by mole in erupted volcanic gases, so a hydrogen species should be the most abundant molecule in the lunar gas, rather than carbon monoxide. This hydrogen is expected to speciate mostly as H2, rather than H2O, at the predicted oxygen fugacity for lunar magma. This difference is important because H2 more easily escapes from the Moon, whereas H2O could freeze out on the lunar surface, and potentially persist within permanently shadowed regions near the poles. We also find that sulfur, rather than carbon, is the third most abundant element in lunar volcanic gas, after hydrogen and oxygen.

期刊论文 2024-05-01 DOI: 10.1016/j.icarus.2024.116009 ISSN: 0019-1035

Problem Statement. . The necessity to review, revise, and supplement existing building regulations in the field of engineering surveys and design is driven by the increasing significance of hydrogeological research. This is in response to the growing trend of urban development on territories (mainly within urban agglomerations) that were previously considered unsuitable for construction due to adverse engineering-geological conditions. The issue becomes particularly relevant against the backdrop of Russia's armed military aggression against Ukraine, which necessitates deeper underground space utilization to construct reliable shelters for protecting civilians from missile and bomb attacks. Under these conditions, new and stricter requirements arise for the content and quality of engineering surveys, design solutions, as well as for measures related to the engineering preparation and protection of territories and individual objects from hazardous geological processes. The aim of this study is to highlight the significance and objectives of engineering-hydrogeological surveys in construction and to propose recommendations for improving the state of survey and design activities in the context of large-scale reconstruction in Ukraine. Research Methodology. . The research involves the systematization and generalization of both domestic and international experience in conducting engineering-geological surveys for construction. Special attention is paid to identifying areas where hydrogeological studies should be prioritized. To formulate requirements and suggestions for improving the regulatory framework in the field of engineering surveys and design, the study analyzes various manifestations of flooding processes. Additionally, the impact of groundwater in various physical states on the strength and deformation properties of soils, as well as the initiation and intensification of hazardous engineering-geological processes, is investigated. Results. The study presents the scientific foundations for improving the regulatory framework in the field of engineering surveys for construction, according to modern requirements. Special emphasis is placed on enhancing the role of hydrogeological research in deepening underground space utilization within urban agglomerations. It is noted that with the expansion of the interaction sphere between projected structures and the geological environment, the influence of groundwater on engineering-geological conditions intensifies, leading to a deterioration in the properties of specific soils and the activation of engineering-geological processes. Scientific Novelty. For the first time, a theoretical justification is provided for the concept of mandatory inclusion of hydrogeological studies in the scope of engineering-geological surveys, even in cases where groundwater is absent within the interaction sphere of the designed structure and the geological environment. Based on the study and systematization of flooding processes, the stages of predicting changes in engineering-hydrogeological conditions have been improved. Practical Significance. The theoretical findings can be used to enhance the regulatory framework in the field of engineering surveys, particularly for developing requirements regarding the content and quality of hydrogeological research. This will improve the reliability of designed buildings and structures while also reducing the risks of hazardous engineering-geological processes emerging or intensifying.

期刊论文 2024-01-01 DOI: 10.26565/2410-7360-2024-60-05 ISSN: 2410-7360

As NASA strives towards a long duration presence on the Moon, it has become increasingly important to learn how to better utilize resources from the lunar surface for everything from habitats, vehicle infrastructure, and chemical extraction. To that end, a variety of lunar simulants have been sourced from terrestrially available volcanic minerals and glass as Apollo regolith is unavailable for experimentation needing large masses. However, while mineralogy and chemical composition can approach that of lunar material in these simulants, there are still distinct non-lunar phases such as hydrates, carbonates, sulfates, and clays that can cause simulants to behave distinctly non-lunar in a variety of processing conditions that maybe applied in-situ to lunar material. Notably, severe glassy bubbling has been documented in a variety of vacuum sintering experiments on JSC-1A lunar mare simulant heated via microwaves. The origins of this outgassing have not been well understood but are normally attributed to the decomposition of non-lunar contaminates intrinsic to virtually all terrestrially sourced simulants. As such, a series of controlled environmental tests were performed to ascertain the origins of the high temperature outgassing and to develop heat treatments that can drive JSC-1A closer to lunar composition and behavior. It was found that in JSC-1A at elevated temperatures distinct gas evolutions of water, carbon dioxide, and sulfur dioxide occur in both inert gas and vacuum. Additionally, the presence of hydrogen during heat treatments was shown to dramatically change gas evolutions, leading to distinctly more lunar-like composition and behavior from JSC-1A simulant.

期刊论文 2023-08-01 DOI: 10.1016/j.icarus.2023.115577 ISSN: 0019-1035

Explosive volcanic eruptions are responsible for producing localized pyroclatic deposits found across the lunar surface. These small localized pyroclastic deposits are thought to have erupted through transient, vulcanian-like eruptions. We used several remote data products, including a water abundance map, to understand the compositional and physical properties of these pyroclastic deposits. Within these deposits, we found strong relationships between water abundance and pyroxene abundance, glass abundance, regolith density scale height, and longitude. These relationships suggest that water abundance can be used to estimate the gas content of an eruption, cooling rate of erupted pyroclasts, optical density of the eruption plume, degree of fragmentation of an eruption, and infer on the distribution of water in the lunar interior. Further, we deduce that the excess water abundance within these pyroclastic deposits represents interior water content, which we tied to other remote measurements that represent important petrological and volcanological parameters to understand eruption dynamics and behavior.

期刊论文 2022-03-15 DOI: 10.1016/j.icarus.2021.114837 ISSN: 0019-1035

We investigated the physical and spectral properties of potential dark mantling deposits (PDMDs) previously and newly identified on the SE limb of the Moon, near the craters Humboldt and Petavius. The goals of this investigation were to constrain the composition and mode of emplacement of these poorly studied deposits, to identify interdeposit variations, and to use these results to draw conclusions about regional and subsurface geologic processes. Our investigation involved an assessment of both the physical properties (size, texture, morphology) and spectral properties (albedo, absorption bands, color ratios) utilizing remote sensing data from multiple lunar orbital missions. We found that many of the SE Limb deposits previously identified as possibly pyroclastic in origin were likely effusively emplaced. However, we also identified several likely pyroclastic deposits, including three not previously mapped. We found that the volcanic deposits across the study area comprise three major spectral groups: one similar to Mare Fecunditatis, one similar to Mare Australe, and one similar to known glassy pyroclastic deposits elsewhere on the Moon. We conclude that volcanism across the SE limb was likely fed from at least two distinct magma source regions, and that the type and extent of surface expression of this volcanic activity was possibly influenced by regional variations in crustal thickness. Our documentation and analysis of the complex volcanic history in this region of the Moon supports ongoing efforts to develop increasingly detailed interpretations of the volcanic history of the entire Moon.

期刊论文 2020-10-01 DOI: 10.1016/j.icarus.2020.113828 ISSN: 0019-1035

Lunar localized pyroclastic deposits are low albedo deposits with areas 2500 km(2)), and (4) provide useful parameters for future volcanological modeling. From this study, we find that: (1) localized pyroclastic deposits exhibit low relief structures, (2) the surface rock abundance and circular polarization ratio of localized pyroclastic deposits display a wide range of values (0.2-0.5% and 0.3-0.6, respectively), (3) the glass abundance of localized pyroclastic deposits vary between 0 and similar to 80 wt.%, (4) there are four types of localized pyroclastic deposits based upon the surface rock abundance and glass abundance parameters, (5) pyroclastic deposits within the same floor-fractured crater tend to have similar properties, and (6) localized pyroclastic deposits are diverse with respect to regional pyroclastic deposits, but a subset of localized pyroclastic deposits have similar physical and mineralogical properties to regional pyroclastic deposits. (C) 2016 Elsevier Inc. All rights reserved.

期刊论文 2017-02-01 DOI: 10.1016/j.icarus.2016.09.025 ISSN: 0019-1035

In this study we examine a lunar pyroclastic deposit (LPD) identified using LROC WAC images, Selene-1 (Kaguya) and Clementine multispectral data, the Chandryann-1's Moon Mineralogy Mapper (M-3), and the LROC WAC-based GLD100 DTM. Selene-1 (Kaguya) and Clementine albedo imagery indicates the presence of pyroclastic deposits located some 40 km to the west-southwest of the crater Yangel in Mare Vaporum, and to the southeast of Sinus Fidel (16.42 degrees N and 3.26 degrees E), and associated with a dome like structure. This dome, which we term Yangel 1 (Ya1), lies immediately to the south of a mare flooded crater which is approximately 7.5 km in diameter, and is partially buried along its southern rim by the domes northern flank. With a diameter of 5.2 km, and a height of 620 m, the dome Ya1 exhibits evidence of pyroclastic volcanic deposits, both on its surface and peripherally. The current study discusses the dome Ya1, the associated deposits and possible relationship between them. (C) 2014 Elsevier Ltd. All rights reserved.

期刊论文 2014-03-01 DOI: 10.1016/j.pss.2014.01.012 ISSN: 0032-0633

The Lunar CRater Observation and Sensing Satellite mission (LCROSS) impacted the moon in a permanently shadowed region of Cabeus crater on October 9th 2009, excavating material rich in water ice and volatiles. The thermal and spatial evolution of LCROSS ejecta is essential to interpretation of regolith properties and sources of released volatiles. The unique conditions of the impact, however, made analysis of the data based on canonical ejecta models impossible. Here we present the results of a series of impact experiments performed at the NASA Ames Vertical Gun Range designed to explore the LCROSS event using both high-speed cameras and LCROSS flight backup instruments. The LCROSS impact created a two-component ejecta plume: the usual inverted lampshade low-angle curtain, and a high speed, high-angle component. These separate components excavated to different depths in the regolith. Extrapolations from experiments match the visible data and the light curves in the spectrometers. The hollow geometry of the Centaur led to the formation of the high-angle plume, as was evident in the LCROSS visible and infrared measurements of the ejecta. Subsequent ballistic return of the sunlight-warmed ejecta curtain could scour the surface out to many crater radii, possibly liberating loosely bonded surface volatiles (e.g., H-2). Thermal imaging reveals a complex, heterogeneous distribution of heated material after crater formation that is present but unresolved in LCROSS data. This material could potentially serve as an additional source of energy for volatile release. (C) 2012 Elsevier Inc. All rights reserved.

期刊论文 2012-03-01 DOI: 10.1016/j.icarus.2011.12.025 ISSN: 0019-1035

Combining UVVIS and NIR Clementine spectral data, we characterize the mineralogy of the different volcanic and crustal materials occurring on the Aristarchus Plateau and its close vicinity, in order to investigate their stratigraphic relationships and understand the nature of the crust in this region of the Moon. From an iterative linear mixture modeling, we provide a comprehensive description of the distribution and amount of surface mixture of the units, and document the stratigraphic relationships in the region of study. The determination of clear relationships and origin of the different units forming the structure of the Plateau is not obvious as the surface materials (to a depth less than 1 km) represent complex materials from the Imbrium impact event. In the Aristarchus region, we show that the Imbrium ejecta has a norite and anorthosite rich composition, with the presence of a clinopyroxene component in the uppermost layer (AER and NE units in the text). Alternatively, AER may form a rather thick horizon emplaced on an NE-rich unit, or AER and NE form a single thick horizon showing a gradational compositional change from AER to NE, from the south to the north of the Plateau. Due to its size, the Aristarchus crater must have penetrated through the Imbrium ejecta and exposed underlying layers formed by pre-Imbrian ejecta and/or the original crust. The regional crustal unit (AP for Aristarchus peak in the text), i.e., the deepest horizon exposed by the Aristarchus crater likely originates from a plus kilometer depth, and is represented by feldspar-rich materials with clinopyroxene and olivine as mafic components. Other deep crustal units, at a stratigraphic level close to the deepest horizon AP, or intermediate between AP and the uppermost horizon AER, and locally distributed in the Aristarchus crater and its vicinity (Aristarchus A crater, and the scarp forming the southern edge of the Plateau), are represented by pyroxene-bearing anorthosite (SC unit) and olivine-rich (OL unit) composition. Although in low abundance, olivine-rich materials are found to be widespread in this region of the Moon. Volcanic pyroclastic deposits (DMD) are widely exposed on the Plateau, with high abundances and a fairly homogeneous composition. We suggest their emplacement could have possibly lasted up to the Eratosthenian, thus leading to a more important pyroclastic activity in time than previously thought, and a rather voluminous and stable reservoir for their source. Based on their UVVIS and NIR spectral characteristics, SW-type materials characterizing the mare basalts west of the Plateau are not detected as a major component across the Plateau. However, SW-type material is significantly present in the complex ejecta of the Aristarchus crater, probably due to the particular morphology of the target, straddling the edge of the Plateau which rises about 2 km above Oceanus Procellarum. The present study based on the integrated visible-near infrared Clementine dataset paves the way for high spatial resolution surveys based on recent photometric observations (e.g.. AMIE/Smart-1) and/or upcoming detailed spectroscopic observations [LISM/Kaguya-Selene; M3 (Moon Mineralogy Mapper)/Chandraayan-1]. (C) 2008 Elsevier Inc. All rights reserved.

期刊论文 2009-01-01 DOI: 10.1016/j.icarus.2008.08.005 ISSN: 0019-1035
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