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This review synthesizes existing research to elucidate the factors driving the distinct tectonic behaviors in the western and eastern Makran subduction zone, focusing on seismic activity, uplift rate, convergence rate, coupling, and subduction angle. The literature identifies the asymmetry in pressure and the variation in subduction angles between the western and eastern parts of the Makran as key factors in defining the region's tectonic patterns. The western region has a steeper subduction angle, resulting in lower pressure, reduced coupling, and decreased seismic activity. This disparity arises from different interactions between the subducted and overriding plates. This article offers an overview of the Makran subduction zone, identifies some knowledge gaps, and suggests directions for future research to improve our understanding of this complex geological region. The review highlights the need for more comprehensive GPS stations and targeted studies on subduction dip angles to better understand the region's tectonic dynamics. [ABSTRACT FROM AUTHOR]

The article presents the results of significance analyses of selected mining and geological variables for an area of underground mining activity. The study area was a region of an underground copper ore mine located in southwest Poland. The input data consisted of satellite radar data from the Sentinel 1 mission as well as mining and geological data. The line-of-sight subsidence, calculated with the use of the small baseline subset method and arranged in time series, was decomposed to extract the vertical component. The significance analysis of individual variables for the observed surface subsidence was performed using the SHapley Additive exPlanations method for the XGBoost machine learning model. The results of the analysis showed that the observed ground surface subsidence velocities were most influenced by the thickness of the PZ3 layer, which is located approximately 200 m above the roof of the mined seam, the thickness of the seam, and the timing of mining. It was also found that the proposed model was able to detect a nonlinear relationship between the analyzed excavations. The most significant influence on ground subsidence over mine excavations are mining parameters such as the spatially averaged thickness of the deposit and the time since liquidation of the deposit. The proposed approach can be successfully employed in planning both mining operations and mine closure in such a manner that the environmental impact is minimized. [ABSTRACT FROM AUTHOR]

On 14 November 2021, a doublet earthquake, each event of which had an Mw of 6.1, struck near Fin in the Simply Folded Belt (SFB) in southern Iran. The first quake occurred at 12:07:04 UTC, followed by a second one just a minute and a half later. The SFB is known for its blind thrust faults, typically not associated with surface ruptures. These earthquakes are usually linked to the middle and lower layers of the sedimentary cover. Identifying the faults that trigger earthquakes in the region remains a significant challenge and is subject to high uncertainty. This study aims to identify and determine the fault(s) that may have caused the doublet earthquake. To achieve this goal, we utilized the DInSAR method using Sentinel-1 to detect deformation, followed by finite-fault inversion and magnetic interpretation to determine the location, geometry, and slip distribution of the fault(s). Bayesian probabilistic joint inversion was used to model the earthquake sources and derive the geometric parameters of potential fault planes. The study presents two potential fault solutions—one dipping to the north and the other to the south. Both solutions showed no significant difference in strike and fault location, suggesting a single fault. Based on the results of the seismic inversion, it appears that a north-dipping fault with a strike, dip, and rake of 257°, 74°, and 77°, respectively, is more consistent with the geological setting of the area. The fault plane has a width of roughly 3.6 km, a length of 13.4 km, and a depth of 5.6 km. Our results revealed maximum displacements along the radar line of sight reaching values of up to −360 mm in the ascending orbit, indicating an unknown fault with horizontal displacements at the surface ranging from −144 to 170 mm and maximum vertical displacements between −204 and 415 mm. Aeromagnetic data for Iran were utilized with an average flight-line spacing of 7.5 km. The middle of the data observation period was considered to apply the RTP filter, and the DRTP method was used. We calculated the gradient of the residual anomaly in the N-S direction due to the direction of the existing faults and folds. The gradient map identified the fault and potential extension of the observed anomalies related to a fault with an ENE-WSW strike, which could extend to the ~ E-W. We suggest that earthquakes occur in the sedimentary cover of the SFB where subsurface faulting is involved, with Hormuz salt acting as an important barrier to rupture. The multidisciplinary approach used in this study, including InSAR and magnetic data, underscores the importance of accurate fault characterization. These findings provide valuable insights into the seismic hazard of the area. [ABSTRACT FROM AUTHOR]

The paper presents the potential of combining satellite radar data and neural networks for quasi-automatic detection of glacier grounding lines. The conducted research covered five years and was carried out in the area of the Amery Ice Shelf. It has a very complex shoreline, so its grounding-line location is uncertain. Thus, it has always been the subject of much research. The main objective of our work was to find out if Synthetic Aperture Radar data combined with a deep learning implementation would enable rapid detection of ice shelf grounding lines over large areas. For this purpose, 290 radar images from the Sentinel-1 satellite covering 46 000 km² were used. Processed by the Differential Interferometry of Synthetic Aperture Radar four-pass method, the images formed a timeconsistent series between 2017 and 2021. As a result of performed calculations, a total length of 1280 km of grounding line was determined. They were validated by comparing with other independent data sources based on manual measurements. It has been demonstrated that the combination of satellite radar data and automated data processing allows for obtaining high-precision results continuously in a very short time. Such an approach allows monitoring of grounding line position in the long term with intervals of less than one week. It enables analysis of the dynamics changes with unprecedented frequency and the identification of patterns. [ABSTRACT FROM AUTHOR]

This paper presents an overview of the surface displacements retrieval capability of the Differential Synthetic Aperture Radar Interferometry algorithm, using Small Baseline Subset (SBAS) technique, in the context of active volcanic areas. Based on Sentinel-1A images, time series displacements fields of the Mauna Loa volcano area over a 2-year time interval (between 2015 and 2017) were received using batch processing. Based on 35 radar images, a total of 179 interferograms have been calculated. Methodology of Synthetic Aperture Radar (SAR) Sentinel-1 ESA satellite mission data processing with small base (SBAS) interferometric techniques from has been presented. The displacements calculated in the satellite’s Line of Sight (LOS) have been presented graphically on maps and graphs. Application of radar interferometry methods in the case of volcanic surface activity research creates new possibilities in the area of permanent monitoring of this type of areas.

Open pit mining hazards monitoring is a crucial task. The paper focuses on the first analysis of surface subsidence in the open pit mining area obtained by Synthetic Aperture Radar active remote sensing technique. Presented methodology of Differential Interferometric SAR provides an excellent data source for mining vertical displacements monitoring. The study was performed in the Belchatow open pit lignite mine in Poland, Central Europe. The SAR SLC imageries acquired by the SENTINEL 1A satellite for the 124-descending track in two periods, between 03.10.2016-15.10.2016 and 15.10.2016-27.10.2016 have been used in the analysis. The post-proceed satellite line of sight (LOS) displacement indicates vertical changes of the surface within the dumping and excavation area. The analyzed region of interests (ROI) shows total subsidence of ca. -67mm, whereas the excavation areas show a trend of terrain uplift during the analyzed periods.

The dynamic development of measurement technology based on the use of laser scanners allows for fast transfer of information, related to terrestrial data, to a virtual environment and enables the creation of three-dimensional models. Because of the growing demand for underground areas inventory, especially historic areas, the creation of 3D numerical models increases in popularity. It allows to increase the geotouristic potential of a particular area and to use solutions in support of the safety of tourists as well as the safety of area itself. The development of the terrestrial laser scanning technique is accompanied simultaneously by the development of means of digital data processing that was obtained in the form of point clouds. Those means use the commercial software as well as software available in the open source system. Both computing environments use algorithms enabling the processing of huge collections of points in automatized mode by using a number of open-access algorithms either freeware or dedicated. The methodology of numerical models development, described in this article, has been presented on the example of underground object “Rzeczka” (“Riese” Complex) located at the Sowie Range (SW Poland).

Underground mining activity in the region of the Upper Silesian Coal Basin (USCB) results in ground displacements scattered on a large area. Both the locations and the velocities of the displacements depend on many factors, such as the current location of the mining front, the mining depth and system, as well as geological conditions. Although SAR interferometry techniques allow the monitoring of such ground displacements, in a regional scale (as is the case of the USCB) SAR images must be appropriately processed (from a number of frames and swaths), and this is the problem addressed in this article. The implementation of algorithms for analyzing time series allows observations of displacements in both time and space. The authors also analyze the influence of mining operations on the road infrastructure and mining waste heaps located in the area and investigate the potential for the monitoring of secondary influence (due to induced seismic tremors). As a result of these investigations, the article presents the quality of the InSAR-SBAS data and the potential for their employment in the measurements. [ABSTRACT FROM AUTHOR]