•Journal• ISSN: 2624-795X
GeoHazards
Multidisciplinary Digital Publishing Institute
About: GeoHazards is an academic journal published by Multidisciplinary Digital Publishing Institute. The journal publishes majorly in the area(s): Geology & Computer science. It has an ISSN identifier of 2624-795X. It is also open access. Over the lifetime, 39 publications have been published receiving 28 citations.
Topics: Geology, Computer science, Landslide, Environmental science, Flood myth
Papers
TL;DR: In this paper , the authors proposed the existence of a buried Kastelli Fault (KF) segment at the SSW-wards prolongation of the emerged at the surface segment.
Abstract: The 27 September 2021 damaging mainshock (Mw6.0) is the first known strong earthquake that ruptured the Arkalochori area, Crete Isl., Greece, during the entire historical period, making it an unexpected event in the long-term sense. The area is characterized by the presence of the normal active Kastelli Fault (KF) striking NNE-SSW and dipping towards ~WNW. The KF, of surface exposure only ~6 km, at its southern tip is truncated by the nearly perpendicular active Nipiditos fault. The main shock was preceded by foreshock activity lasting for ~3.9 months, thus the mainshock turned out to be an expected event in the short-term sense. Maximum ground subsidence of ~20 cm was estimated from InSAR images, but this also incorporates deformation that may have been caused by the largest aftershock (Mw5.1) of 28 September 2021. The fault model produced from the inversion of InSAR observations indicated strike 216°, dip towards ~NW at angle 53°, rake −95°, and is consistent with fault-plane solutions obtained from routine moment tensor analysis. The geodetic seismic moment calculated from the Okada’s formalism is 1.14 × 1018 N·m (Mw6.0), while a maximum slip of 1.03 m was found at depths from 3.5 km to 5 km. The entire aftershock epicenters cloud strikes a ~SW-NE direction but is distributed in two clusters, the southern and the northern ones. The foreshock cloud, the main slip patch, the deformation area, and the strongest aftershocks all fall within the southern cluster. The foreshocks concentration at the deepest edge of the main slip patch was a foreshadow of the mainshock nucleation area. The northern cluster, which is very likely due to the gradual expansion of aftershocks, is situated in the KF hanging wall block. To interpret the main seismic slip in the southern cluster area we propose the existence of a buried KF segment at the SSW-wards prolongation of the emerged at the surface segment. Assuming a rectangular seismic fault stress drop Δσ~7 bars was found. However, for a circular fault area, which in this case is more realistic, we get Δσ = 55 bars. This is a relatively large value for Greek earthquakes but is explainable by increased fault rigidity as a result of the long repeat time of strong earthquakes in KF.
15 citations
TL;DR: In this paper , the authors evaluate the possible correlation between the correlation dimension and the seismic moment rate for different late Quaternary active fault data, shallow crustal earthquakes, and GPS on the island of Sumatra Probabilistic Seismic Hazard Analysis (PSHA).
Abstract: This study intends to evaluate the possible correlation between the correlation dimension (DC) and the seismic moment rate for different late Quaternary active fault data, shallow crustal earthquakes, and GPS on the island of Sumatra Probabilistic Seismic Hazard Analysis (PSHA). The seismicity smoothing was applied to estimate the DC of active faults (DF) and earthquake data (DE) and then to correlate that with the b-value, which will be used to identify seismic hazard functions (SHF) along with the Sumatra Fault Zone (SFZ). The seismicity based on GPS data was calculated by the seismic moment rate that is estimated based on pre-seismic horizontal surface displacement data. The correlation between DF, DE, and the b-value was analyzed, and a reasonable correlation between the two seismotectonic parameters, DF-b, and DE-b, respectively, could be found. The relatively high DC coincides with the high seismic moment rate model derived from the pre-seismic GPS data. Furthermore, the SHF curve of total probability of exceedance versus the mean of each observation point’s peak ground acceleration (PGA) shows that the relatively high correlation dimension coincides with the high SHF. The results of this study might be very beneficial for seismic mitigation in the future.
11 citations
TL;DR: In this paper , a set of qualitative methods were used to derive and articulate an inventory and analysis of hazards/disasters in Cameroon, and the hazards have been structured along four profiles: a classification of all hazard types plaguing Cameroon into natural, potentially socio-natural, technological, and social and anthropogenic hazards.
Abstract: The paucity of a comprehensive document on Cameroon’s hazard/disaster risk profile is a limitation to the country wide risk assessment and adequate disaster resilience. This article narrows this gap by retrospectively exploring Cameroon’s hazard/disaster profile. This has been achieved through an investigative approach that applies a set of qualitative methods to derive and articulate an inventory and analysis of hazards/disasters in Cameroon. The findings indicate that Cameroon has a wide array and high incidence/frequency of hazards that have had devastating consequences. The hazards have been structured along four profiles: a classification of all hazard types plaguing Cameroon into natural, potentially socio-natural, technological, and social and anthropogenic hazards; occurrence/origin of the hazards; their impacts/effects to the ‘at risk’ communities/populace and potential disaster management or mitigation measures. In-depth analysis indicate that natural hazards have the lowest frequency but the potential to cause the highest fatalities in a single incident; potentially socio-natural hazards affect the largest number of people and the widest geographical areas, technological hazards have the highest frequency of occurrence; while social/anthropogenic hazards are the newest in the country but have caused the highest population displacement. Arguably, the multi-hazard/disaster inventory presented in this article serves as a vital preliminary step to a more comprehensive profile of Cameroon’s disaster risk profile.
11 citations
TL;DR: In this paper , a quantitative risk assessment of the Cascadia basin area was conducted, which involved a detailed characterization of the proposed injection site to understand baseline stress and pressure conditions and identify individual faults or fault zones with the potential to slip and thereby generate seismicity.
Abstract: Offshore basalts, most commonly found as oceanic crust formed at mid-ocean ridges, are estimated to offer an almost unlimited reservoir for CO2 sequestration and are regarded as one of the most durable locations for carbon sequestration since injected CO2 will mineralize, forming carbonate rock. As part of the Solid Carbon project, the potential of the Cascadia Basin, about 200 km off the west coast of Vancouver Island, Canada, is investigated as a site for geological CO2 sequestration. In anticipation of a demonstration proposed to take place, it is essential to assess the tendency of geologic faults in the area to slip in the presence of CO2 injection, potentially causing seismic events. To understand the viability of the reservoir, a quantitative risk assessment of the proposed site area was conducted. This involved a detailed characterization of the proposed injection site to understand baseline stress and pressure conditions and identify individual faults or fault zones with the potential to slip and thereby generate seismicity. The results indicate that fault slip potential is minimal (less than 1%) for a constant injection of up to ~2.5 MT/yr. This is in part due to the thickness of the basalt aquifer and its permeability. The results provide a reference for assessing the potential earthquake risk from CO2 injection in similar ocean basalt basins.
9 citations
TL;DR: In this article , the persistent scatterers InSAR (PSI) method is employed to process the series of Sentinel 1-A/B synthetic aperture radar (SAR) images acquired between 2015 and 2021 along ascending and descending orbits for the selected areas in Gangtok, Sikkim, to detect potentially active, landslide-prone areas.
Abstract: The Himalayan state of Sikkim is prone to some of the world’s largest landslides, which have caused catastrophic damage to lives, properties, and infrastructures in the region. The settlements along the steep valley sides are particularly subject to frequent rainfall-triggered landslide events during the monsoon season. The region has also experienced smaller rock slope failures (RSF) after the 2011 Sikkim earthquake. The surface displacement field is a critical observable for determining landslide depth and constraining failure mechanisms to develop effective mitigation techniques that minimise landslide damage. In the present study, the persistent scatterers InSAR (PSI) method is employed to process the series of Sentinel 1-A/B synthetic aperture radar (SAR) images acquired between 2015 and 2021 along ascending and descending orbits for the selected areas in Gangtok, Sikkim, to detect potentially active, landslide-prone areas. InSAR-derived ground surface displacements and their spatio-temporal evolutions are combined with field investigations to better understand the state of activity and landslide risk assessment. Field investigations confirm the ongoing ground surface displacements revealed by the InSAR results. Some urban areas have been completely abandoned due to the structural damage to residential housing, schools, and office buildings caused by displacement. This paper relates the geotechnical investigations carried out on the ground to the data obtained through interferometric synthetic aperture radar (InSAR), focusing on the triggering mechanisms. A strong correlation between seasonal rainfall and landslide acceleration, as well as predisposing geological-structural setting, suggest a causative mechanism of the landslides.
9 citations
Performance Metrics
| Year | Papers |
|---|---|
| 2026 | 12 |
| 2025 | 82 |
| 2024 | 63 |
| 2023 | 29 |
| 2022 | 27 |