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The identification of fault types and their locations is crucial for power system protection/operation when a fault occurs in the lines. In general, this involves a human-in-the-loop analysis to capture the transient voltage and current signals using a common format for transient data exchange for power systems (COMTRADE) file. Then, protection engineers can identify the fault types and the line locations after the incident. This paper proposes intelligent and novel methods of faulty line and location detection based on convolutional neural networks in the power system. The three-phase fault information contained in the COMTRADE file is converted to an image file and extracted adaptively by the proposed CNN, which is trained by a large number of images under various kinds of fault conditions and factors. A 500 kV power system is simulated to generate different types of electromagnetic fault transients. The test results show that the proposed CNN-based analyzer can classify the fault types and locations under various conditions and reduce the fault analysis efforts.

A study involving soil radon monitoring using RAD-7 instrument was carried out near Balakot-Bagh (B-B) Fault line hit by a 7.6 magnitude earthquake in October 2005. The study aimed to determine the spatial distribution of soil radon gas levels and the relationship between the soil radon gas and fracture density. Eleven soil samples were collected near the fault line, and 56 more samples (fourteen each from the adjoining district/area). Field measurements were made in the summer season of 2013, as a part of continuous measurement for regular monitoring the area for radon emanation and for observing the anomalies with previous values. The study area is located in Lesser Himalayas, North Pakistan, the Balakot–Bagh (B–B) fault in the Hazara–Kashmir Syntaxis. Soil gas radon concentrations were found higher near the Balakot-Bagh Fault line with an average value of 11.9 kBq m - 3 compared to other sites of the study area with an average value of around 6.5 kBq m - 3 . The radon value near the fault line is 70% higher as compared to the surrounding area.

The power utility companies have been trying to identify and locate three-phase transmission line faults in the shortest possible time in order to prevent economic losses. In the last few decades, technology used for power system protection has evolved from electromechanical devices to solid state and processor-based intelligent devices. This study presents the design and implementation of a wavelet analysis-based fault detection and identification module that contemplates the analysis of high frequency transients produced during faults. The design was implemented on a cost effective low-end embedded system. The proposed logic employs a multi-resolution wavelet analysis of high frequency details in the range of 5–10 kHz. The amount of high frequency components present in the transformed current signals, obtained after processing, identifies the fault. The ground and line-to-line faults were classified on the basis of the adaptive thresholds obtained from system behaviour. The proposed approach, after the completion of simulations, was implemented on a digital signal controller. The developed fault detection and identification prototype was successful in accurately identifying the power system faults, thus validating the feasibility of the proposed methodology.

The 2016 moment magnitude (Mw) 7.8 Kaikoura earthquake was one of the largest ever to hit New Zealand. Hamling et al. show with a new slip model that it was an incredibly complex event. Unlike most earthquakes, multiple faults ruptured to generate the ground shaking. A remarkable 12 faults ruptured overall, with the rupture jumping between faults located up to 15 km away from each other. The earthquake should motivate rethinking of certain seismic hazard models, which do not presently allow for this unusual complex rupture pattern. Science, this issue p. eaam7194 On 14 November 2016 (local time), northeastern South Island of New Zealand was struck by a major moment magnitude (Mw) 7.8 earthquake. The Kaikoura earthquake was the most powerful experienced in the region in more than 150 years. The whole of New Zealand reported shaking, with widespread damage across much of northern South Island and in the capital city, Wellington. The earthquake straddled two distinct seismotectonic domains, breaking multiple faults in the contractional North Canterbury fault zone and the dominantly strike-slip Marlborough fault system. Earthquakes are conceptually thought to occur along a single fault. Although this is often the case, the need to account for multiple segment ruptures challenges seismic hazard assessments and potential maximum earthquake magnitudes. Field observations from many past earthquakes and numerical models suggest that a rupture will halt if it has to step over a distance as small as 5 km to continue on a different fault. The Kaikoura earthquake's complexity defies many conventional assumptions about the degree to which earthquake ruptures are controlled by fault segmentation and provides additional motivation to rethink these issues in seismic hazard models. Field observations, in conjunction with interferometric synthetic aperture radar (InSAR), Global Positioning System (GPS), and seismology data, reveal the Kaikoura earthquake to be one of the most complex earthquakes ever recorded with modern instrumental techniques. The rupture propagated northward for more than 170 km along both mapped and unmapped faults before continuing offshore at the island's northeastern extent. A tsunami of up to 3 m in height was detected at Kaikoura and at three other tide gauges along the east coast of both the North and South Islands. Geodetic and geological field observations reveal surface ruptures along at least 12 major crustal faults and extensive uplift along much of the coastline. Surface displacements measured by GPS and satellite radar data show horizontal offsets of ~6 m. In addition, a fault-bounded block (the Papatea block) was uplifted by up to 8 m and translated south by 4 to 5 m. Modeling suggests that some of the faults slipped by more than 20 m, at depths of 10 to 15 km, with surface slip of ~10 m consistent with field observations of offset roads and fences. Although we can explain most of the deformation by crustal faulting alone, global moment tensors show a larger thrust component, indicating that the earthquake also involved some slip along the southern end of the Hikurangi subduction interface, which lies ~20 km beneath Kaikoura. Including this as a fault source in the inversion suggests that up to 4 m of predominantly reverse slip may have occurred on the subduction zone beneath the crustal faults, contributing ~10 to 30% of the total moment. Although the unusual multifault rupture observed in the Kaikoura earthquake may be partly related to the geometrically complex nature of the faults in this region, this event emphasizes the importance of reevaluating how rupture scenarios are defined for seismic hazard models in plate boundary zones worldwide. (A and B ) Photos showing the coastal uplift of 2 to 3 m associated with the Papatea block [labeled in (C)]. The inset in (A) shows an aerial view of New Zealand. Red lines denote the location of known active faults. The black box indicates the Marlborough fault system. (C ) Three-dimensional displacement field derived from satellite radar data. The vectors represent the horizontal displacements, and the colored background shows the vertical displacements. On 14 November 2016, northeastern South Island of New Zealand was struck by a major moment magnitude (Mw) 7.8 earthquake. Field observations, in conjunction with interferometric synthetic aperture radar, Global Positioning System, and seismology data, reveal this to be one of the most complex earthquakes ever recorded. The rupture propagated northward for more than 170 kilometers along both mapped and unmapped faults before continuing offshore at the island's northeastern extent. Geodetic and field observations reveal surface ruptures along at least 12 major faults, including possible slip along the southern Hikurangi subduction interface; extensive uplift along much of the coastline; and widespread anelastic deformation, including the ~8-meter uplift of a fault-bounded block. This complex earthquake defies many conventional assumptions about the degree to which earthquake ruptures are controlled by fault segmentation and should motivate reevaluation of these issues in seismic hazard models.

Abstract The fast individuation and modeling of faults responsible for large earthquakes are fundamental for understanding the evolution of potentially destructive seismic sequences. This is even more challenging in case of buried thrusts located in offshore areas, like those hosting the 9 November 2022 Ml 5.7 (M w 5.5) and M L 5.2 earthquakes that nucleated along the Apennines compressional front, offshore the northern Adriatic Sea. Available on- and offshore (from hydrocarbon platforms) geodetic observations and seismological data provide robust constraints on the rupture of a 15 km long, ca. 24° SSW-dipping fault patch, consistent with seismic reflection data. Stress increase along unruptured portion of the activated thrust front suggests the potential activation of longer portions of the thrust with higher magnitude earthquake and larger surface faulting. This unpleasant scenario needs to be further investigated, also considering their tsunamigenic potential and possible impact on onshore and offshore human communities and infrastructures.

The solution of static elastic deformation of a homogeneous, orthotropic elastic uniform half-space with rigid boundary due to a non-uniform slip along a vertical strike-slip fault of infinite length and finite width has been studied. The results obtained here are the generalisation of the results for an isotropic medium having rigid boundary in the sense that medium of the present work is orthotropic with rigid boundary which is more realistic than isotropic and the results for an isotropic case can be derived from our results. The variations of displacement with distance from the fault due to various slip profiles have been studied to examine the effect of anisotropy on the deformation. Numerically it has been found that for parabolic slip profile, the displacement in magnitude for isotropic elastic medium is greater than that for an orthotropic elastic half-space, but, in case of linear slip, the displacements in magnitude for an orthotropic medium is greater than that for the isotropic medium.

Hydraulic fracturing has been inferred to trigger the majority of injection-induced earthquakes in western Canada, in contrast to the Midwestern United States, where massive saltwater disposal is the dominant triggering mechanism. A template-based earthquake catalog from a seismically active Canadian shale play, combined with comprehensive injection data during a 4-month interval, shows that earthquakes are tightly clustered in space and time near hydraulic fracturing sites. The largest event [moment magnitude (Mw) 3.9] occurred several weeks after injection along a fault that appears to extend from the injection zone into crystalline basement. Patterns of seismicity indicate that stress changes during operations can activate fault slip to an offset distance of >1 km, whereas pressurization by hydraulic fracturing into a fault yields episodic seismicity that can persist for months.

The Pawnee M5.8 earthquake is the largest event in Oklahoma instrument recorded history. It occurred near the edge of active seismic zones, similar to other M5+ earthquakes since 2011. It ruptured a previously unmapped fault and triggered aftershocks along a complex conjugate fault system. With a high-resolution earthquake catalog, we observe propagating foreshocks leading to the mainshock within 0.5 km distance, suggesting existence of precursory aseismic slip. At approximately 100 days before the mainshock, two M ≥ 3.5 earthquakes occurred along a mapped fault that is conjugate to the mainshock fault. At about 40 days before, two earthquakes clusters started, with one M3 earthquake occurred two days before the mainshock. The three M ≥ 3 foreshocks all produced positive Coulomb stress at the mainshock hypocenter. These foreshock activities within the conjugate fault system are near-instantaneously responding to variations in injection rates at 95% confidence. The short time delay between injection and seismicity differs from both the hypothetical expected time scale of diffusion process and the long time delay observed in this region prior to 2016, suggesting a possible role of elastic stress transfer and critical stress state of the fault. Our results suggest that the Pawnee earthquake is a result of interplay among injection, tectonic faults, and foreshocks.

Understanding the main geothermal components such as clay cap, reservoir, heat source and faults structure can reduce the risk at the drilling stage. The role of the faults is very important since it can be a recharge/discharge medium of geothermal fluid. One method that can be used to identify the faults is the gravity method. The combination of the upward continuation and second vertical derivative (ML-SVD) methods is carried out to characterize the geological structure both the slope direction, depth estimation, dip estimation and type of structure. Upward continuation is carried out from a height of 0 - 2000 meters with an interval of 250 meters. SVD filter is applied at each height level. ML-SVD result shows that the fault structures at the study area have a value of dip > 70° with various fault configurations. Some faults are estimated at a certain depth under a layer of rock. ML-SVD shows a circular pattern that indicated as a caldera structure. The fault orientation of the study area tends SW-NE and NW-SE with dip perpendicular to the strike.

Radon (222Rn) is the second most common cause of lung cancer after smoking. As radon poses a significant risk to human health, radon-affected areas should be identified to ensure people’s awareness of risk and remediation. The primary goal of this research was to investigate the local natural radioactivity (in soils, groundwater, and indoors) because of the presence of tuff outcrops (from middle–lower Pleistocene volcanic activity) that naturally produce radioactive gas radon at Cerveteri (Rome, Central Italy). The results of the radon survey highlighted moderate (>16,000 Bq/m3) but localized anomalies in soils in correspondence with a funerary site pertaining to the Etruscan Necropolis of Cerveteri, which extends over a volcanic rock plateau. Indoor radon measurements were performed at several tuff-made dwellings, and the results showed medium-low (<200 Bq/m3) values of indoor radon except for some cases exceeding the reference level (>300 Bq/m3) recommended by the 2013/59 Euratom Directive. Although no clinical data exist regarding the health effects of thoron (220Rn) on humans, the study of 220Rn average activity concentration in the soil gas survey reveals new insights for the interpretation of radon sources that can affect dwellings, even taking into account the considerable difference in the half-lives of 222Rn and 220Rn.