Article
Geochemistry & Geophysics
M. Ersen Aksoy, Mustapha Meghraoui, Alina Polonia, M. Namik Cagatay, Asli Zeynep Yavuzoglu, Sebnem Onder, Umut B. Ulgen, Luca Gasperini
Summary: This study focused on the westernmost segment of the North Anatolian fault in NW Turkey and found that the western termination of the 1912 earthquakes' surface ruptures ends about 37 km offshore in the Gulf of Saros. The research suggests that the eastern extension of the 9 August earthquake reached the Central Marmara Basin, with implications for seismic hazard in the Marmara coastal area.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Geosciences, Multidisciplinary
L. Jiao, Y. Klinger, L. Scholtes
Summary: Through numerical modeling, this study demonstrates that during shearing of a layer of brittle material, oblique Riedel fractures nucleate with a regular spacing controlled by the layer's thickness, which then influences the spatial structuration of the entire fault system. An analysis of horizontal stress distribution reveals a threshold at a ratio of 1.5 between inter-Riedel distance and material thickness, beyond which new fractures nucleate due to a switch from compressional to tensional stress.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Engineering, Environmental
George Papathanassiou, Sotiris Valkaniotis, Athanassios Ganas
Summary: This research focuses on the island of Lefkada, Greece, analyzing landslide data from two shallow strike-slip faulting earthquakes in 2003 and 2015. The study finds that landslide patterns are not controlled by a single parameter, but result from a combination and interaction of seismic, morphological, and geological factors. Specifically, parameters such as slope angle, geology, and fault rupture/asperities are closely related to the highest landslide densities.
BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
(2021)
Article
Geosciences, Multidisciplinary
Yann Klinger
Summary: This study investigates the origin of unexpected high frequency emissions during earthquakes and finds that the most likely source is the interaction between nearby misaligned faults. This finding highlights the discrete nature of strike-slip fault segments at seismogenic crustal scale and adds new constraints to earthquake rupture scenarios.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Environmental Sciences
Yuqing He, Teng Wang, Li Zhao
Summary: In transtensional regions, the slip distribution of earthquakes can be influenced by the oblique motion of faults and the presence of fault segmentations. By studying the slip distribution of the Lake Hovsgol earthquake in Mongolia, researchers found that the slip directions at different depths were controlled by the left-lateral motion of the Mondy Fault, which also shaped the asymmetric graben structure in the region.
Article
Geosciences, Multidisciplinary
Qing Bian, Shang Deng, Huixi Lin, Jun Han
Summary: The connection between source rock and reservoir separated by salt strata is a global problem. This paper focuses on the No. 5 strike-slip fault passing through salt layers in the Tarim Basin. The seismic data reveals different structural styles in the salt layer, including transpression, transtension, and pure strikeslip. The impact of deep strike-slip salt tectonics on petroleum exploration is discussed using data from seven wells, showing that thicker salt layers result in poorer production.
MARINE AND PETROLEUM GEOLOGY
(2022)
Article
Environmental Sciences
Jiuyuan Yang, Caijun Xu, Yangmao Wen
Summary: On January 23 and March 25, 2022, two right-lateral strike-slip earthquakes with magnitudes larger than 5.5 occurred near Hala Lake in northeastern Tibet. These two events are the largest since the 1927 Hala Lake earthquake. The lack of surface rupture makes it difficult to determine the seismogenic faults and coseismic rupture behaviors of the two events. However, studying these events can provide valuable insights into the seismic hazard of the region.
Article
Geology
Ehsan Kosari, Matthias Rosenau, Sabrina Metzger, Onno Oncken
Summary: Understanding the seismogenic behavior of megathrusts is crucial for predicting seismic hazards in subduction zones. However, the relationship between frictional heterogeneity at depth and upper-plate deformation is not fully understood. Using a seismotectonic model, we found that the frictional locking heterogeneity generates segmented along-strike strain patterns in the short term but less pronounced permanent strain patterns in the long term. Our results suggest that along-strike upper-plate strain patterns can help interpret lateral variations in seismogenic behavior.
Article
Environmental Sciences
Nikos Svigkas, Anastasia Kiratzi, Andrea Antonioli, Simone Atzori, Cristiano Tolomei, Stefano Salvi, Marco Polcari, Christian Bignami
Summary: The tectonics of the Epirus region in northwestern Greece is characterized by the active collision of the Apulian continental lithosphere with the Eurasian plate, resulting in frequent seismic activity and significant surface deformation. The 2020 earthquake sequence near Kanallaki village showed reverse faulting with two slip events and one slip patch, indicating distinct active fault geometries in the area. The seismic activity near the triple junction of western Greece differs from the Kanallaki 2020 activity in terms of acting stresses.
Article
Geosciences, Multidisciplinary
Rakesh K. Dumka, Sandip Prajapati, Donupudi SuriBabu, Kandadai Swamy, Girish Ch Kothyari, Kapil Malik
Summary: Based on nearly a decade of GPS data, the geodetic investigation of the Kachchh Rift Basin (KRB) in western India reveals regional compressive stress and the existence of strike-slip and thrust motion. The geological observations corroborate the measurement model.
GEOLOGICAL JOURNAL
(2023)
Article
Geochemistry & Geophysics
Tae-Kyung Hong, Junhyung Lee, Jeongin Lee, Seongjun Park, Byeongwoo Kim, Sungchan Choi
Summary: Earthquakes in the Korean Peninsula often occur in subsurface hidden faults that are difficult to identify before seismic activity. In this study, a midcrustal subsurface hidden fault in a seismically quiet region of the central Korean Peninsula was investigated, which caused the M-L 4.1 earthquake on October 28, 2022. Combined analysis of seismicity, geophysical properties, and geological features provided constraints on the geometry of this hidden fault. The fault extends to the surface where a lineament with low gravity anomalies is present.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Article
Geochemistry & Geophysics
Nienke Brinkman, Simon C. Stahler, Domenico Giardini, Cedric Schmelzbach, Amir Khan, Alice Jacob, Nobuaki Fuji, Clement Perrin, Philippe Lognonne, Eric Beucler, Maren Bose, Savas Ceylan, Constantinos Charalambous, John F. Clinton, Martin van Driel, Fabian Euchner, Anna Horleston, Taichi Kawamura, Brigitte Knapmeyer-Endrun, Guenole Mainsant, Mark P. Panning, William T. Pike, John-Robert Scholz, Johan O. A. Robertsson, William B. Banerdt
Summary: This study uses geophysical methods to observe ongoing tectonic processes on Mars, finding that the Marsquakes indicate a predominantly extensional setting, with normal faulting in the Cerberus Fossae region and uncertainty in the fault regime in the Orcus Patera region. The single-station limitation is explored, showing that even data recorded by one station can reasonably constrain the mechanisms.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2021)
Article
Multidisciplinary Sciences
Laurent Bollinger, Yann Klinger, Steven L. Forman, Odonbaatar Chimed, Amgalan Bayasgalan, Ulziibat Munkhuu, Ganzorig Davaasuren, Tulga Dolgorsuren, Bayarsaikhan Enkhee, Demberel Sodnomsambuu
Summary: The spatial distribution of large earthquakes in slowly deforming continental regions is not random, as seismic activity concentrates on specific structures. However, the long return time for large earthquakes along these structures may lead to the misconception that earthquakes in slowly deforming regions are randomly located.
SCIENTIFIC REPORTS
(2021)
Article
Geochemistry & Geophysics
Charu Kamra, Sumer Chopra, R. B. S. Yadav
Summary: The study determines the focal mechanism solutions and source parameters of recent earthquakes in the northeastern region of India. The tectonics in the region are complex due to compressional forces from all sides caused by the collision of plates. The focal mechanisms are used to understand the stress field in the region, revealing different tectonic regimes in different subregions. The stress drop of the earthquakes is found to be dependent on the focal mechanism type, seismic moment, and hypocentral depths, and the results are compared with another region in western India.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Article
Geochemistry & Geophysics
Mathilde Marchandon, James Hollingsworth, Mathilde Radiguet
Summary: This study investigates the potential artifact of Shallow Slip Deficit (SSD) in fault slip models for large strike-slip earthquakes. Results show that neglecting topography, variations in elastic properties, and lack of data coverage around the fault can significantly bias the slip model, leading to artificial SSD. Additionally, correlated data noise with low amplitude can also produce significant artificial SSD, highlighting the importance of systematic estimation of model uncertainty in inversion studies.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Environmental Sciences
Varvara Tsironi, Athanassios Ganas, Ioannis Karamitros, Eirini Efstathiou, Ioannis Koukouvelas, Efthimios Sokos
Summary: Kinematic behavior of active landslides in the area of Panachaikon Mountain was studied. The maximum displacement rate of each landslide was found to be located at its center. There is a correlation between rainfall and landslide motion, with the increase in total seasonal rainfall controlling the increase in displacement rate.
Article
Engineering, Geological
V Sarhosis, C. Giarlelis, C. Karakostas, E. Smyrou, I. E. Bal, S. Valkaniotis, A. Ganas
Summary: Two strong earthquakes occurred in the Thessaly region of Greece in March 2021, causing significant damage to masonry buildings but leaving modern reinforced concrete structures relatively unharmed. This highlights the vulnerability of existing masonry building stock constructed using traditional methods and materials, and the need for systematic solutions in the future.
BULLETIN OF EARTHQUAKE ENGINEERING
(2022)
Article
Engineering, Geological
George Papathanassiou, Sotiris Valkaniotis, Athanassios Ganas, Alexandros Stampolidis, Dimitra Rapti, Riccardo Caputo
Summary: This study investigates the secondary effects of liquefaction phenomena during the seismic sequence in March 2021 in Thessaly, Central Greece. By comparing the distribution of liquefaction phenomena with geomorphological conditions, the study highlights the influence of historical evolution on liquefaction, providing a method to reduce liquefaction hazard areas.
ENGINEERING GEOLOGY
(2022)
Article
Geochemistry & Geophysics
Maria Mesimeri, Athanassios Ganas, Kristine L. Pankow
Summary: A seismic crisis occurred in the western Corinth Gulf offshore Marathias from December 23, 2020, lasting several months and generating thousands of small magnitude earthquakes. The seismic activity migrated from west to east, with an increase in Vp/Vs values for each earthquake cluster. The clusters also contained short interevent time, repeating earthquakes, possibly related to aseismic slip or fluid migration.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Geochemistry & Geophysics
Fabrice Hollender, Nikolaos Theodoulidis, Armand Mariscal, Thierry Chaudat, Jamison Steidl, Zafeiria Roumelioti
Summary: Borehole accelerometers are used to record deep ground movements and have become important in seismic and earthquake engineering. Coupling borehole accelerometers with the geological environment presents challenges, but using glass beads as a coupling solution proved effective. Test results showed minimal differences between surface and borehole accelerometer signals, further demonstrating the reversible nature of the installation using glass beads.
SEISMOLOGICAL RESEARCH LETTERS
(2023)
Article
Environmental Studies
Aikaterini Servou, Nikolaos Vagenas, Nikolaos Depountis, Zafeiria Roumelioti, Efthimios Sokos, Nikolaos Sabatakakis
Summary: In this paper, the rockfall susceptibility of three different limestone rock sequences in Lefkada island, Greece, was examined under aseismic and seismic conditions. Through field measurements and engineering geological surveys, a rockfall inventory was prepared. Two-dimensional rockfall simulations were performed, and spatial distribution maps of the intensity were generated, showing significant variation among the rock masses due to their inherent engineering geological characteristics.
Editorial Material
Geosciences, Multidisciplinary
Ioannis Kassaras, Athanassios Ganas, Paolo Pace
Article
Geosciences, Multidisciplinary
Vasiliki Zygouri, Ioannis Koukouvelas, Athanassios Ganas, Christina Tsimi
Summary: The Pidima-Anthia Fault offers insight into the long palaeoseismic records of the Eastern Messinia Fault Zone. Analysis of palaeoseismology and geomorphology reveals the fault's slip rate and earthquake history.
JOURNAL OF STRUCTURAL GEOLOGY
(2023)
Article
Geography, Physical
J. Robertson, G. P. Roberts, A. Ganas, M. Meschis, D. M. Gheorghiu, R. P. Shanks
Summary: This study conducts spatio-temporal analysis on Pleistocene palaeoshorelines in southwestern Crete. By using Cl-36 exposure dating on wave-cut platforms and mapping of palaeoshorelines, it is found that the Late Quaternary uplift rates increase from west to east, suggesting that an offshore extensional fault may also contribute to the uplift.
QUATERNARY SCIENCE REVIEWS
(2023)
Article
Chemistry, Analytical
Elias Fakiris, George Papatheodorou, Dimitris Christodoulou, Zafeiria Roumelioti, Efthimios Sokos, Maria Geraga, Vasileios Giannakopoulos, Xenophon Dimas, George Ferentinos
Summary: This study conducted long-term monitoring experiments on gas-bearing pockmarks and active faults using a distributed temperature sensor (DTS) system in Patras Gulf pockmark field. The results showed that spectral analysis can separate the temperature footprint of background environmental components from high-frequency temperature residuals, which may be correlated to seismic activity. Although the relationship between seismicity and seabed water temperature changes was not systematic, four thermal events were postulated to have a causative link with local seismic activity. The promising preliminary results suggest that the DTS system is a low-cost monitoring system worth testing for a longer period.
Article
Chemistry, Multidisciplinary
Dimitris Christodoulou, George Papatheodorou, Maria Geraga, Giuseppe Etiope, Nikos Giannopoulos, Sotiris Kokkalas, Xenophon Dimas, Elias Fakiris, Spyros Sergiou, Nikos Georgiou, Efthimios Sokos, George Ferentinos
Summary: This paper provides a complete mapping of the Patras Gulf Pockmark field and generates new knowledge regarding the fluid escape structures, fluid pathways, their origin, and the link with seismic activity. The study shows that the morphometric parameters and spatial distribution patterns of the pockmarks are directly linked to tectonic structures. Methane is the main component of the fluids, and earthquake activity prompts the activation of the field.
APPLIED SCIENCES-BASEL
(2023)
Review
Geosciences, Multidisciplinary
Niki Evelpidou, Athanassios Ganas, Anna Karkani, Evangelos Spyrou, Giannis Saitis
Summary: The investigation of past sea-level changes in the Corinth Gulf provides valuable information for understanding the impacts of earthquakes and tectonic activities in the area. By combining geomorphological and geodetic data, researchers have created a comprehensive geodatabase that reveals the relative sea-level changes in the Gulf. The findings suggest that the southern coast has undergone uplift while the northern coast has experienced subsidence.
Article
Geochemistry & Geophysics
Sotiris Valkaniotis, Vincenzo De Novellis, Athanassios Ganas, Eugenio Sansosti, Vincenzo Convertito, Pierre Briole, Varvara Tsironi, Ilektra Karasante, Ioannis Karamitros
Summary: On December 2, 2020, a moderate earthquake occurred near Kallithea in central Greece, causing local damage. Geodetic analysis and seismological data revealed a permanent subsidence of 7 cm on the ground surface, indicating a rupture on a WNW-ESE striking, SSW-dipping normal fault. The earthquake's effects were disproportionate to its magnitude, possibly due to its shallow depth and high efficiency. The geodetic data analysis also suggested the possibility of a hidden normal fault or a secondary fault branching off the Kallithea fault responsible for the surface deformation.
Proceedings Paper
Engineering, Multidisciplinary
Konstantinos G. Nikolakopoulos, Aggeliki Kyriou, Efthimios Sokos, Stathis Bousias, Elias Strepelias, Peter Groumpos, Vassiliki Mpelogianni, Zafeiria Roumelioti, Anna Serpetsidaki, Dimitrios Paliatsas, Panagiotis Stephanopoulos, Athanassios Ganas, Vassiliki Betty Charalampoulou, Theodoros Athanasopoulos
Summary: Climate change poses a direct threat to infrastructure, highlighting the need for reliable and cost-effective monitoring systems. The PROION project aims to develop a platform for continuous monitoring of high-priority infrastructures and decision-making support through the integration of instrumental and remote sensing measurements.
EARTH RESOURCES AND ENVIRONMENTAL REMOTE SENSING/GIS APPLICATIONS XIII
(2022)
Article
Geosciences, Multidisciplinary
Athanassios Ganas, Yariv Hamiel, Anna Serpetsidaki, Pierre Briole, Sotiris Valkaniotis, Charalampos Fassoulas, Oksana Piatibratova, Haralambos Kranis, Varvara Tsironi, Ioannis Karamitros, Panagiotis Elias, Emmanuel Vassilakis
Summary: A strong and shallow earthquake occurred near Heraklion, Crete, Greece on September 27, 2021. The earthquake resulted in significant ground deformation near the village of Arkalochori, but there were no surface ruptures. By analyzing geodetic data, the researchers were able to map the movements of the Earth's surface during and after the earthquake.