Article
Geology
Volkan Karabacak, Taylan Sancar, Gokhan Yildirim, I. Tonguc Uysal
Summary: This study used U-Th geochronology to date syntectonic calcites on fault planes in the southern branch of the western North Anatolian fault in northern Turkey. The isotopic ages clustered around different periods during the past 700,000 years. The most significant cluster peak at 510.5 +/- 9.5 ka is consistent with maximum cumulative strike-slip offset data and GPS measurements of tectonic plate motions, indicating that the current configuration of the fault began around 500,000 years ago or earlier in the southern Marmara region.
Article
Engineering, Geological
Luca Gasperini, Filippo Zaniboni, Alberto Armigliato, Stefano Tinti, Gianluca Pagnoni, Mehmet Sinan Ozeren, Marco Ligi, Francesca Natali, Alina Polonia
Summary: Based on morphobathymetric and seismic reflection data, this study examines a large landslide body in the eastern Sea of Marmara and its potential to cause tsunamis along the North Anatolian Fault. The results suggest that the sliding of the landslide mass could generate tsunamis exceeding 15-20 m in the eastern Sea of Marmara. The study emphasizes the need for more marine geological/geophysical data to better understand the hazards and develop emergency plans.
Article
Geosciences, Multidisciplinary
Denizhan Vardar, Hakan Alp, Sinan Demirel, Hande Aykurt Vardar, Bedri Alpar
Summary: New high-resolution seismic reflection and magnetic data collected offshore of the Ganos Fault in NW Turkey reveal a complex fault pattern. A new tectonic model connecting onshore fault patterns to transtensional basins in the Sea of Marmara has been proposed based on these data, highlighting the presence of three main faults controlling the deformation pattern in the region.
Article
Geosciences, Multidisciplinary
Murat Sahin, Cenk Yaltirak, Fatih Bulut, Asli Garagon
Summary: The North Anatolian Fault Zone in northern Turkey is a dextral system operating between the Eurasian and Anatolian plates. It deforms at a slip rate of about 18 mm/year across the Marmara Sea south of Istanbul. Historical earthquake data suggests that M7+ earthquakes occur every approximately 250 years, but there have been none in this section since the 1766 and 1754 earthquakes. Identifying the stress change caused by the 2019 M5.8 Istanbul-Silivri earthquake is crucial for understanding its impact on the critically stressed Marmara Sea segments of the North Anatolian Fault Zone. The analysis shows that the mainshock occurred on a SW-NE striking splay fault, generating a stress increase of up to three bars, which has the potential to generate an M7+ earthquake.
EARTH PLANETS AND SPACE
(2022)
Article
Geochemistry & Geophysics
Y. Benjelloun, J. de Sigoyer, S. Garambois, J. Carcaillet, Y. Klinger
Summary: The study investigates the Holocene paleoseismic activity of the North Anatolian Fault (NAF) in the Marmara region, using high-resolution satellite imagery and terrestrial cosmogenic nuclide dating to map the middle strand. The research found evidence of multiple major ruptures and determined the horizontal slip rate in the area, suggesting that the last large earthquakes occurred between 1065 CE and the 14th-18th centuries CE, indicating a potential for future destructive seismic activity.
Article
Geochemistry & Geophysics
Seda Okay Gunaydin, Christopher C. Sorlien, Marie-Helene Cormier, Burcu Barin, Leonardo Seeber, Michael S. Steckler, Gunay Cifci, Derman Dondurur, Hulya Kurt, H. Mert Kucuk, Orhan Atgin, Ozkan Ozel
Summary: Geodetic monitoring and seismicity patterns indicate that the Northern Branch of the North Anatolian Fault (NAF) absorbs most of the relative motion between the Eurasia and Anatolia plates in the northern Marmara Sea. However, historical seismicity suggests that the Central Branch of the NAF is also hazardous, with earthquakes occurring diffusely in the southern Marmara Sea. Recent geophysical data collection along the adjacent shelf revealed the presence of three long faults and several shorter, discontinuous faults, highlighting the significant seismic hazard for southern coastal cities.
Article
Geochemistry & Geophysics
Wenyuan Fan, Andrew J. Barbour, Elizabeth S. Cochran, Guoqing Lin
Summary: Studies have found that in the past decade, earthquake catalogs in Southern California can help systematically evaluate dynamic triggering patterns. It was discovered that approximately 1 out of every 5 global M-w >= 6 earthquakes can dynamically trigger microearthquakes in Southern California, showing both instantaneous and delayed triggering responses.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Geochemistry & Geophysics
Zeynep Yilmaz, Ali Ozgun Konca, Semih Ergintav
Summary: This study builds a 3-D model of the region, including the basins and the 3-D fault geometry, to study the competing effects of deep basins and the interseismic locking distribution using the observed Global Navigation Satellite System velocities. The study concludes that the basins along the fault localize the interseismic strain, leading to slightly deeper-estimated locking depths.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Geochemistry & Geophysics
Eyup Sopaci, A. Arda Ozacar
Summary: The analysis of the Mw5.8 earthquake in the Marmara Sea raises the question of whether it can trigger or advance the expected larger earthquake near Istanbul. Different simulation strategies were used to analyze its potential effect on the seismic cycle, considering various views of friction. The results show that while the moderate earthquake cannot instantly trigger the locked fault segment, it can significantly advance the failure time. The long-term effect on the seismic cycle is static when failure is far in time, but dynamic effects become more significant when failure is imminent.
Article
Geochemistry & Geophysics
Denizhan Vardar, Hakan Alp, Sinan Demirel, Hande Vardar, Bedri Alpar
Summary: The study used high-resolution seismic data to differentiate sedimentary successions on both sides of the Ganos Fault, identifying distinct stratigraphic patterns and depositional characteristics. The findings highlight significant differences in sedimentary structures between the two sides of the fault, providing insights into the tectonic controls on sediment distribution and thickness.
ANNALS OF GEOPHYSICS
(2021)
Article
Geosciences, Multidisciplinary
Pierre Henry, M. Sinan Ozeren, Nurettin Yakupoglu, Ziyadin Cakir, Emmanuel de Saint-Leger, Olivier Desprez de Gesincourt, Anders Tengberg, Cristele Chevalier, Christos Papoutsellis, Nazmi Postacioglu, Ugur Dogan, Hayrullah Karabulut, Gulsen Ucarku, M. Namik Cagatay
Summary: This study provides insights into the hydrodynamic processes associated with earthquake-induced submarine slope destabilization. It reveals that smaller earthquakes cause sediment resuspension and weak currents, while larger earthquakes trigger debris flows and turbidity currents with variable velocities. The study also highlights the occurrence of delayed turbidity currents after earthquakes.
NATURAL HAZARDS AND EARTH SYSTEM SCIENCES
(2022)
Article
Geochemistry & Geophysics
Jaime E. Delano, Rich W. Briggs, Christopher B. DuRoss, Ryan D. Gold
Summary: The study compares the use of physical scale bars with total station or GNSS control points to constrain SfM models for paleoseismic trench mapping. Despite slightly decreased accuracy, scale bars significantly simplify the workflow and eliminate the need for specialized survey equipment.
SEISMOLOGICAL RESEARCH LETTERS
(2021)
Article
Geosciences, Multidisciplinary
Zachary D. Smith, W. Ashley Griffith
Summary: This study investigates the development of off-fault damage through successive tensile loading. The results show that fracture density increases during each earthquake cycle, and pulverized rock can be produced at low strain rates.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geochemistry & Geophysics
Eric Beauce, Robert D. van der Hilst, Michel Campillo
Summary: This study used data from the Dense Array for North Anatolia (DANA) seismic network in 2012 to build a new catalog of microseismicity and analyzed its statistical properties. The study found that microseismicity mainly occurs off the main fault, with the most active regions being the Lake Sapanca step-over and near the Akyazi fault. Based on previous research, these microseismic activities are believed to be driven by residual stresses from the Izmit earthquake.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Geochemistry & Geophysics
R. Gastineau, J. de Sigoyer, P. Sabatier, S. C. Fabbri, F. S. Anselmetti, A. L. Develle, M. Sahin, S. Gunduz, F. Niessen, A. C. Gebhardt
Summary: The study reveals 14 earthquake-induced turbidites in Lake Iznik since the past two millennia, providing valuable insights into the historical seismic activity of the region. The discovery of two previously unknown underwater fault structures using geophysical methods sheds light on the seismic hazard in the area. Additionally, the interpretation of sediments on both sides of the southernmost fault suggests co-seismic displacement linked to the 1065 CE historical earthquake, emphasizing the importance of understanding past seismic events for seismic risk assessment.
Article
Geochemistry & Geophysics
Nicolas Castro-Perdomo, Renier Viltres, Frederic Masson, Yann Klinger, Shaozhuo Liu, Maher Dhahry, Patrice Ulrich, Jean-Daniel Bernard, Remi Matrau, Abdulaziz Alothman, Hani Zahran, Robert Reilinger, P. Martin Mai, Sigurjon Jonsson
Summary: This study presents a new GPS velocity field to investigate the recent seismic dynamics of the southernmost part of the Gulf of Aqaba, revealing a decreasing locking depth from inland towards the southern junction with the Red Sea rift, along with a small systematic left-lateral residual motion. Additionally, estimates suggest elevated seismic hazard in the Gulf area, implying possible end of current interseismic period on main faults.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Geochemistry & Geophysics
Bo Li, Baoning Wu, Han Bao, David D. Oglesby, Abhijit Ghosh, Alice-Agnes Gabriel, Lingsen Meng, Risheng Chu
Summary: This study investigates how earthquake rupture heterogeneity and directivity affect back-projection results using synthetic earthquake models. The experiments show that back-projection can only track heterogeneous rupture processes and the amplitude of beam power depends on the spatial heterogeneity and rupture directivity. The study also provides a theoretical equation to explain the relationship between the wavelength of heterogeneity and synthetic seismogram frequency.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Geochemistry & Geophysics
S. Baize, S. Amoroso, N. Belic, L. Benedetti, P. Boncio, M. Budic, F. R. Cinti, M. Henriquet, P. Jamsek Rupnik, B. Kordic, S. Markusic, L. Minarelli, D. Pantosti, S. Pucci, M. Spelic, A. Testa, S. Valkaniotis, M. Vukovski, J. Atanackov, J. Barbaca, M. Bavec, R. Brajkovic, V Brcic, M. Caciagli, B. Celarc, R. Civico, P. M. De Martini, R. Filjak, F. Iezzi, A. Moulin, T. Kurecic, M. Metois, R. Nappi, A. Novak, M. Novak, B. Pace, D. Palenik, T. Ricci
Summary: On 29 December 2020, a shallow earthquake of magnitude M-w 6.4 struck northern Croatia, causing significant coseismic environmental effects such as surface deformation, liquefaction, and slope failures. The surface rupture, named the Petrinja-Pokupsko Fault, is discontinuous and shows evidence of slip on a right lateral fault. Liquefaction extends over an area of nearly 600 km(2) around the epicentre. The environmental effects of the earthquake are consistent with the usual scaling relationships.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Geochemistry & Geophysics
Zheng Tang, Jordi Julia, P. Martin Mai, Walter D. Mooney, Yanqiang Wu
Summary: A high-resolution 3D crustal and upper-mantle shear-wave velocity model of Northeast China is established through joint inversion of receiver functions and fundamental-mode Rayleigh wave phase velocities, providing insights into the internal structure of the Earth.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Geography, Physical
Irene Puliti, Stefano Pucci, Fabio Villani, Massimiliano Porreca, Lucilla Benedetti, Gaetano Robustelli, Anna Gueli, Giuseppe Stella
Summary: This study investigated the footwall of the Paganica normal fault, the source of the 2009 L'Aquila earthquake in Italy, using integrated geological and geomorphological approaches. The results showed that the fault activity led to long-term fluvial incision and footwall uplift. The research also found an increasing relief growth and suggested that the fault's ongoing activity might trigger larger seismic events.
Article
Geosciences, Multidisciplinary
Jennifer M. Tarnowski, Christodoulos Kyriakopoulos, David D. Oglesby, Michele L. Cooke, Aviel Stern
Summary: This study uses 3-D dynamic finite-element models to investigate the potential rupture paths of earthquakes along the San Gorgonio Pass fault system in southern California. The results suggest that throughgoing rupture from the southeast to northwest is more likely, emphasizing the influence of fault geometry and stress patterns on rupture propagation.
Article
Geochemistry & Geophysics
R. Azzaro, S. Pucci, F. Villani, R. Civico, S. Branca, M. Cantarero, E. De Beni, P. M. De Martini, F. R. Cinti, M. Caciagli, L. Cucci, D. Pantosti
Summary: Volcano-tectonic earthquakes at Mt. Etna in Italy produce impressive surface faulting despite their moderate magnitude. Researchers used field data, high-resolution photogrammetric surveys, and geological-morphological observations to analyze the structure and growth process of the fault. They found a complex pattern of brittle structures and identified a prevailing right-lateral displacement in the northern section of the fault.
Article
Geochemistry & Geophysics
P. A. Selvadurai, P. Galvez, P. M. Mai, S. D. Glaser
Summary: In this study, numerical models based on the rate-and-state frictional framework were used to investigate earthquake sequences using laboratory driven heterogeneous frictional properties. The fault surface was binarized to simulate frictional heterogeneity, producing a barcode-like pattern. The numerical simulations generated burst-like seismic events and aseismic transients, and the calculations were validated by comparing experimental measurements.
Article
Geochemistry & Geophysics
Yuxiang Tang, P. Martin Mai
Summary: This study uses a stochastic finite-fault simulation approach to simulate ground motions for the 2021 Mw 5.9 Woods Point earthquake in southeastern Australia. The simulations are validated by comparing them with observed ground motions, and the study provides important information for local seismic hazard analysis through investigating attenuation parameters, path parameters, and local site effects.
BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA
(2023)
Article
Geochemistry & Geophysics
Olaf Zielke, Paul Martin Mai
Summary: Multicycle earthquake rupture simulators generate sequences of earthquakes for statistical analysis, providing a deeper understanding of earthquake machine and informing seismic hazard assessment. It works with complex fault geometries, different stress accumulation approximations, elastic signal propagation velocity, and considers various fault conditions. It allows identification of dominant parameters and provides probabilities of future ruptures based on previous behavior.
BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA
(2023)
Article
Geosciences, Multidisciplinary
Baoning Wu, Christodoulos Kyriakopoulos, David D. Oglesby, Kenny J. Ryan
Summary: Earthquake stress drop Delta sigma is related to fault slip via Delta sigma = C·μ·D/Lc, where μ, D, and Lc denote shear modulus, average slip, and fault dimension. C is controlled by the system geometry and characterizes the effective stiffness of the system. We investigated how C is influenced by fault burial depth, dip angle, and slip direction and found that C decreases with smaller burial depth and dip angle. Our results provide insights into the magnitude-dependent stress drops of megathrust earthquakes.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Engineering, Geological
Bora Yalcin, Olaf Zielke, P. Martin Mai
Summary: In this study, we developed a predictive model to quantify the changes in porosity and permeability of porous media caused by accumulated fault slip. By combining deformation modeling with triangular dislocations and linearized poro-elasticity equations, we applied the model to the Ghawar field fault map and rock-types. Results showed that long-term accumulated slip on rough strike-slip fault surfaces can lead to a variation in porosity of +/- 1% and a maximum absolute permeability change of 22.5%. Using these findings, we determined the slip-related permeability changes for every fault on the Ghawar fault map, accounting for their length, location, and orientation. The resulting permeability distribution model can be used as the initial permeability model for porous media in fractured reservoirs.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2023)
Article
Geography
Stefano Pucci, Giuseppe Avellone, Antonio Contino, Alessandro Incarbona, Leonardo Sagnotti, Attilio Sulli, Enrico Di Stefano, Alessandra Smedile, Anna Maria Gueli, Giuseppe Stella
Summary: We have presented a new 1:25,000-scale geological map of the lower Belice River valley, a region that experienced a devastating seismic sequence in 1968. The map provides unprecedented detail and precision on the spatial distribution and growth geometries of the sedimentary sequence. It offers new insights on the long-lasting tectonic forces in the area, which may be related to potential seismic sources.
Article
Geochemistry & Geophysics
A. Testa, P. Boncio, S. Baize, F. Mirabella, S. Pucci, B. Pace, M. Riesner, C. Pauselli, M. Ercoli, L. Benedetti, A. Di Chiara, R. Civico
Summary: The study reveals that the Anghiari fault has experienced seven paleo-earthquakes in the past, with a slip rate of over 0.2 mm/yr averaged over the last 25,000 years and a recurrence interval of about 2,500-3,200 years. Furthermore, paleoseismological analysis indicates the presence of an extensional stress field throughout the sedimentation of the faulted strata.
Article
Geochemistry & Geophysics
Rinhui Kim, Michael Witek, Sung-Joon Chang, Jung-A Lim, P. Martin Mai, Hani Zahran
Summary: We estimated group-velocity dispersion curves for Rayleigh and Love waves in Saudi Arabia and nearby countries. By combining our data with dispersion curves from previous studies, we developed a new S-velocity model for the Arabian plate and nearby regions. Our findings reveal different tectonics between the southern and northern Red Sea regions, as well as the presence of low-velocity anomalies beneath Cenozoic volcanism in the Arabian Peninsula. The observed radial anisotropy suggests the presence of toroidal mantle flow and vertical flow in specific regions.
