Multispectral remote sensing of hydrothermal alteration in volcanogenic massive sulfide (VMS) ore systems in mafic crust is relatively uncommon, in part due to the short-wave infrared spectral similarity of several key alteration minerals: epidote, chlorite, actinolite, and serpentine. In this study, we developed regional mosaic generation and classification workflows for Advanced Spaceborne Thermal

Combining molecular simulation and experimental results provides a more detailed understanding of gas sorption in kerogens than either approach in isolation. Porosity and chemical functionality are the main differences between kerogens affecting the methane adsorption, whereas which one is the key control has not been stated clearly. Molecular dynamic (MD) simulations with matrix and slit pore models

Mineral and organic matter compositions & pore structures of fine-grained shale influence reservoir properties. To improve the understanding of spatial heterogeneity in core-sized samples, methods of microscale X-ray fluorescence (μXRF) mapping, (ultra-) small-angle x-ray scattering [(U)SAXS] and wide-angle X-ray scattering (WAXS) have been used to determine elemental, pore-structure variations at

In this study, the use of Sentinel-1 interferometric coherence data as a tool for crop monitoring has been explored. For this purpose, time series of images acquired by Sentinel-1 and 2 spanning 2017 have been analysed. The study site is an agricultural area in Sevilla, Spain, where 16 different crop species were cultivated during that year. The time series of 6-day repeat-pass coherence measured at

Rockfall causes a large number of accidents and fatalities in steep environments. A realistic quantification of rockfall risk is thus crucial for an effective prevention of damages and loss of lives. The estimation of rockfall and block volumes for different return periods thereby remains a major challenge. In this paper, we present a straightforward rockfall frequency model (RFM: Rockfall Frequency

This study focuses on the vibrational response of a landslide mass to natural and man-induced vibrations. The landslide is located in the Molise region (Italy) and involves a coastal slope extending approximately 5 km2, from the Petacciato village to the coastline. Landslide activity, well documented since 1909 with historical reactivation resulting in severe damage to infrastructure and the ancient

Passive microwave remote sensing of soil moisture is an underdetermined problem, as observed microwave emission from the landscape is affected by a variety of unknown surface parameters. Increasing observation information is an effective means to make retrievals more robust. In this study, a multi-temporal and multi-angular (MTMA) approach is proposed using SMOS (Soil Moisture and Ocean Salinity) satellite

The variations of mechanical properties of coals in nano-to-micro scale play vital roles in defining the coal deformative and failure behaviors with a wide range of engineering applications, including coal stimulation for gas recovery and/or CO2 sequestration in coal seams. Based on the assumption that the heterogeneity in the mechanical properties of coals is combinedly determined by the mineralogical/carbon

The accurate description of the stress-strain relationships of rock and soil is very important to analyze its mechanical properties, but the forms of stress-strain curves are different, which can be softening, hardening, or ideal elastoplastic. With the change of confining pressure, they can be transformed into each other. Taking one of loess as the research object, consolidated drained triaxial tests

The chemistry of rare earth elements (REE) and selected critical elements was examined in the high volatile A bituminous Pond Creek coal in Pike County, Kentucky. The Pond Creek coal has been one of the most important coal resources in eastern Kentucky but, up to now, no modern methods, such as Inductively coupled plasma – mass spectroscopy (ICP-MS) have been applied to the characterization of the

Shale diagenesis controls the generation, migration and accumulation of hydrocarbons through time and has become a frontier area of study in the fields of sedimentology and petroleum geology. There have been only a few studies on the generation of organic pores in lacustrine shale oil reservoirs during the oil generation thermal evolution stage. In this study, lacustrine organic-rich shale samples

To extract hydrocarbons from unconventional shale systems, it is necessary to assess oil retention and accumulation. This study presents experimental findings on oil retention, migration, and accumulation in a lacustrine shale system from the Chang 7 member of the Upper Triassic Yanchang Formation, Ordos Basin. 68 core samples were collected from the target layer to investigate the migration behavior

The residual strength of sliding basal soils plays a pivotal role not only in the movement of bedding landslides controlled by clay-rich interlayers but also in remobilized granular deposits. Many studies have focused on better understanding the residual shear behaviors of clayey and granular soils under relatively low shear rates. However, the residual strength varies with various clay fractions for

Understanding the sources of error that affect the accuracy of current coarse burned area products is crucial to identifying weaknesses and limitations of burned area (BA) algorithms. In this paper, we propose methods to analyse sources of errors of global BA products, which are applied to assess a widely used product, (FireCCI51), created under the ESA climate change initiative programme. The effect

Using laminar or turbulent flow equations indiscriminately to describe groundwater flows in fracture networks may result in large errors. We propose a new method for simulating steady-state groundwater flows in two- and three-dimensional fracture networks by separating laminar flows and turbulent flows in individual fractures. Poiseuille's law is employed when the flow is laminar, while Swamee and

In a deep geological repository (DGR) system, the buffer layer is indispensable to ensuring the safe disposal of high-level radioactive nuclear waste (HLW). Because the heat generated by the decay of the spent nuclear fuel in a canister is released to the surrounding buffer layers, the bentonite buffer material experiences long-term high-temperature conditions. Therefore, the variations in physical

Active remote sensing by laser scanning (LiDAR) has markedly improved the mapping of a cave environment with an unprecedented level of accuracy and spatial detail. However, the use of laser intensity simultaneously recorded during the scanning of caves remains unexplored despite it having promising potential for lithological mapping as it has been demonstrated by many applications in open-sky conditions

Unlike the free biomarkers, which can be routinely recovered via solvent extraction, the bound biomarkers are covalently linked to the kerogen or asphaltene macrostructures and are more resistant to secondary alteration processes. Although similarities have been identified between these two types of biomarkers using different techniques, it remains unclear how the kerogen- and asphaltene-bound biomarkers

A slope digital twin is a virtual slope model that is able to continuously, even in real-time, learn from actual observations (e.g., monitoring data, slope performance records, and site investigation data) obtained from its physical counterpart to enhance the performance of the slope model. This study proposes a practical framework to develop a slope digital twin and describes its application to predict

Inertinite in coals contains important information regarding the palaeo-wildfire history and can provide insights into its triggers and relationship with the evolution of local ecosystems. However, such information in the Middle Jurassic coal is often overlooked, and the impacts of incidental mercury emission from wildfires on the mercury enrichment in coal are also underestimation. In this study,

The estimation of particulate organic carbon (POC) concentrations from satellite images can provide crucial spatiotemporal continuous observation data for the carbon cycle and ecological environmental governance. Here, we developed a novel inversion algorithm for deriving POC in inland water based on remote sensing and geochemical isotopes, which is summarized as follows. First, we developed empirical

Large-scale land surface phenology (LSP) information has been developed from remote sensing-based vegetation indices (VIs) data. However, there are considerable discrepancies and uncertainties in the LSP data products for the start and end of growing seasons (SOS; EOS) as different vegetation indices and algorithms are used. Here, we used the TROPOspheric Monitoring Instrument (TROPOMI) solar-induced

We propose a method for evaluating the risks of slope failure induced by heavy rain over a wide area by combining infiltration analysis, surface flow analysis, and slope stability analysis based on three-dimensional limit equilibrium method. The influence of the resolution of terrain data is also examined. To determine rainfall-induced water transportation, we employ an infiltration analysis, using

Soil moisture is strongly spatially variable and scale dependent, but there is a lack of research focusing on factors that link soil actual evaporation to the spatial distribution of topsoil moisture at the slope scale. External factors (e.g., meteorological) have similar effects across entire slopes; hence, this paper instead explores the internal factors controlling differential soil actual evaporation

Coal rock water immersion softening is common in coal geology, and it is of great significance to effectively control and utilize the process of water immersion softening and fracturing of coal. In this paper, the progressive failure and softening characteristics of coal samples under localized or full water immersion conditions were determined based on the stress-strain and acoustic emission (AE)

High spatial resolution commercial satellite data provide new opportunities for terrestrial monitoring. The recent availability of near-daily 3 m observations provided by the PlanetScope constellation enables mapping of small and spatially fragmented burns that are not detected at coarser spatial resolution. This study demonstrates, for the first time, the potential for automated PlanetScope 3 m burned

The estimation of biophysical variables is at the core of remote sensing science, allowing a close monitoring of crops and forests. Deriving temporally resolved and spatially explicit maps of parameters of interest has been the subject of intense research. However, deriving products from optical sensors is typically hampered by cloud contamination and the trade-off between spatial and temporal resolutions

Although generally given little attention in vegetation studies, ground-dwelling (terricolous) lichens are major contributors to overall carbon and nitrogen cycling, albedo, biodiversity and biomass in many high-latitude ecosystems. Changes in biomass of mat-forming pale lichens have the potential to affect vegetation, fauna, climate and human activities including reindeer husbandry. Lichens have a

The emission of solar-induced chlorophyll fluorescence (F) is a pivotal process to infer vegetation health and functioning that can be monitored by remote sensing. However, most of the current remote sensing methods retrieve only F at top-of-canopy level, therefore making the link with physiological processes occurring at photosystem level not trivial. In this study, we develop a novel machine learning

Evapotranspiration (ET) is a primary process for water and heat transfer between the land and atmosphere. The spatial contextual information-based surface temperature versus vegetation index triangle (temperature-based triangle) is one of the most famous and widely applied methods for regional ET estimation from remotely sensed data. However, the determination of temporally variable satellite scene-specific

The construction and operation of the Sichuan-Tibet railway require constructing extensive supporting facilities along its route. Sichuan-Tibet transportation corridor features high mountains and deep valleys where land resources suitable for such purposes are very limited. As a result, safe utilization of the torrential fan along the railway becomes essential. Focus on buildings at the torrential

We propose a physically-based methodology for sea-surface skin-temperature (SST) retrievals from daytime spectra recorded by the hyperspectral Infrared Atmospheric Sounding Interferometer (IASI). The approach, which takes sun light into account, minimizes the differences between measured and computed radiances at numerous points within two windows centered near 3.7 and 4.0 μm. We demonstrate that,

Landslides are major threats to the construction and operation of electric towers of the Sichuan–Tibet Grid Interconnection Project (STGIP). The long, narrow project corridor is vulnerable to different types of landslides, making risk management a difficult task. In this study, a kinematic-based, landslide risk management framework that includes hazard analysis, risk estimation, risk evaluation, and

Calibration and validation of aboveground biomass (AGB) (AGB) products retrieved from satellite-borne sensors require accurate AGB estimates across hectare scales (1 to 100 ha). Recent studies recommend making use of non-destructive terrestrial laser scanning (TLS) based techniques for individual tree AGB estimation that provide unbiased AGB predictors. However, applying these techniques across large

A full understanding of the interaction mechanisms among flow-like landslides and impacted protection structures is still an open issue. Although several approaches, from experimental to numerical, have been used so far, a thoroughly assessment of the hydromechanical behaviour of the landslide body is achievable only through a multiphase and large deformation approach. This paper firstly proposes a

This study presents a methodology to integrate two simulation codes, i.e., cohesive element-based numerical manifold method (Co-NMM) and unified pipe network method (UPM), for 2D coupled two-phase seepage-stress analysis of waterflooding processes in fractured rock masses. The Co-NMM is an extension of the numerical manifold method (NMM) and designed for efficiently addressing continuity-discontinuity

Various types of floating macroalgae and other floating matters have been reported in the global oceans and inland waters, and their remote detection has relied primarily on passive optical sensors. These sensors provide multiple spectral bands and frequent revisits, yet they all suffer from clouds. Synthetic aperture radar (SAR) imagers are active sensors that overcome this obstacle, yet their capacity

This paper introduces a method for estimating a series of sea state parameters from satellite-borne synthetic aperture radar (SAR). The method was realized in a near real time (NRT) application which allows for the processing of data from different satellites and modes. The algorithm estimates the total significant wave height Hs, dominant and secondary swell and windsea wave heights, first, and second

It is essential and important for engineering design and maintenance to systematically investigate the physical–mechanical properties of frozen soils. At present, a series of tests have been carried out on frozen silty clay based on improved testing techniques. The results indicate that brittle and plastic failures occur for frozen silty clay under low and high confining pressures, respectively, and

Many uncertainties exist in geotechnical engineering. Spatial variability is a type of uncertainty that has received more and more attention in recent years. Scale of fluctuation (SOF) is a parameter for measuring the spatial variability of soil properties. To investigate the proper method for computing the SOF of soil properties, two types of methods (auto-correlation function method (ACM), and variance

The Bayu Tunnel is the most problematic tunnel project in the Lhasa-Nyingchi section of the Sichuan-Tibet Railway. Rockbursts have occurred frequently during the construction process, which has seriously threatened the safety of construction workers and equipment. Aiming at the rockburst hazard prediction problem of the Bayu Tunnel, in this paper an integrating method of combination weighting and matter-element

In the mountainous areas passed by the Sichuan–Tibet Railway, rockfall is one of the important geological hazards with characteristics of unpredictable and sudden occurrences. For high and steep slopes, this study employs nap-of-the-object photogrammetry with the characteristic of close flight distance to reconstruct a 3D geological model, which is clear and qualified for discontinuity identification

Characterizing error structures in precipitation products not only facilitates their proper applications for scientific and practical purposes but also helps improve their retrieval algorithms and processing methods. Despite the fact that multiple precipitation products have been assessed in the literature, factors that affect their error structures remain inadequately addressed. By interpreting 60

In recent years, various techniques have been developed to generate crop-type maps based on remote sensing data. Wheat and barley are two major cereal crops cultivated as the first and fourth largest grain crops across the globe. The variations in spectral temporal profile of both crops are generally insignificant at small scales and therefore the two crops are phenologically fairly clearly separated;

Estimating proportion of area from a stratified random sample and reference class labels obtained by ground visit or interpretation of satellite imagery is a common strategy in land cover monitoring. Confidence intervals for the proportion of area are typically estimated using the Wald interval, a procedure that is known to yield less than nominal coverage (i.e., undercoverage) when the proportion

Accurate and up-to-date maps of built-up areas are crucial to support sustainable urban development. Earth Observation (EO) is a valuable data source to cover this demand. In particular, Sentinel-1 Synthetic Aperture Radar (SAR) and Sentinel-2 MultiSpectral Instrument (MSI) missions offer new opportunities to map built-up areas on a global scale. Using Sentinel-2 images, recent urban mapping efforts

Remote detection and monitoring of the vegetation responses to stress became relevant for sustainable agriculture. Ongoing developments in optical remote sensing technologies have provided tools to increase our understanding of stress-related physiological processes. Therefore, this study aimed to provide an overview of the main spectral technologies and retrieval approaches for detecting crop stress

The availability and quality of quad-pol synthetic aperture radar (SAR) datasets has increased substantially since the early 2000s, allowing for polarimetrically complete investigations of freshwater ice. These investigations have lead to improved ice classification methods, new understanding of microwave-ice scattering processes, and the potential for new methods to extract ice observables. Such analyses

Discovering groundwater resources in a fault-controlled aquifer system appears to be a viable solution to water scarcity in the mountainous areas of Taiwan. Regoliths, fractured bedrock, and faults commonly exist in such aquifer systems. To investigate the groundwater behavior in the three subsurface media, a 3-D hybrid model (equivalent porous media/discrete fracture network) involving various in

Reconstructing the ages and magnitudes of prehistoric extreme events that are recorded in landforms and sediments allows us to capture the full range of frequency-magnitudes and estimate the expected time for the repetition of a catastrophic event. The Eastern Himalayan Syntaxis and its surrounding areas are highly prone to the occurrence of river blocking. Previous studies have re-established three

Deep rock tunneling exhibits a significant three-dimensional (3D) space effect. The complex stress path and extrusion deformation during excavation are the most significant and decisive factors in the stability and construction safety of a deep tunnel. 3D and forward numerical analyses based on generalized Zhang–Zhu (GZZ) strength criterion are performed to investigate the principal stress rotation

Thermal maturation is traditionally evaluated based on vitrinite reflectance (VRo) measurements and its relationship to oil and gas generation and diagenetic transformation are ingrained in many basin modeling tools. However, vitrinite derives from higher land plants that evolved in Devonian. In pre-Devonian rocks graptolite reflectance (GR) is the most significant thermal index for establishing thermal

This paper presents the first attempt to develop the facies model of the entire coal deposit belonging to the Carboniferous productive sequence located in the western part of the Upper Silesian Coal Basin. To achieve this objective, six seams from the Knurów deposit were examined. The deposit belongs to the largest producer of coking coal in Europe, which is Jastrzębska Spółka Węglowa SA (Polish state-run