A. Arda Özacar

A. Arda Özacar

Orta Dogu Teknik Üniversitesi

H-index: 22

Asia-Turkey

Professor Information

University

Orta Dogu Teknik Üniversitesi

Position

Geological Engineering Department

Citations(all)

2121

Citations(since 2016)

1009

Cited By

1511

hIndex(all)

22

hIndex(since 2016)

19

i10Index(all)

30

i10Index(since 2016)

24

Email

University Profile Page

Orta Dogu Teknik Üniversitesi

Research & Interests List

Seismology

Geophysics

Geology

Top articles of A. Arda Özacar

Ege Denizi Kıyıları İçin Sismik Tsunami Tehlike Analizi: Olasılıksal Yaklaşım

Ege Denizi Kıyıları İçin Sismik Tsunami Tehlike Analizi: Olasılıksal Yaklaşım Show/Hide Menu Hide/Show Apps Logout Türkçe Türkçe Search Search Login Login OpenMETU OpenMETU About About Open Science Policy Open Science Policy Communities & Collections Communities & Collections Help Help Frequently Asked Questions Frequently Asked Questions Guides Guides Thesis submission Thesis submission MS without thesis term project submission MS without thesis term project submission Publication submission with DOI Publication submission with DOI Publication submission Publication submission Supporting Information Supporting Information General Information General Information Copyright, Embargo and License Copyright, Embargo and License Contact us Contact us Ege Denizi Kıyıları İçin Sismik Tsunami Tehlike Analizi: Olasılıksal Yaklaşım Date 2023-11-17 Author DOĞAN, GÖZDE GÜNEY …

Authors

GÖZDE GÜNEY DOĞAN,Ahmet Cevdet Yalçıner,Atilla Arda Özacar,Zeynep Gülerce,Duygu Tüfekçi Enginar,Mehmet Lütfi Süzen,BİLGE KARAKÜTÜK,Hakan Bora Okay,ONUR KANUN,Onur Pekcan,MEHMET SEMİH YÜCEMEN

Publish Date

2023/11/17

Simulation of Large Earthquake Synchronization and Implications On North Anatolian Fault Zone

The North Anatolian Fault (NAF) has a history of large quasi-periodic large earthquake clusters. This study investigates the phenomenon with a model consisting of three strong velocity-weakening (VW) asperities separated by velocity-strengthening VS barriers in a 2.5D model governed by rate-and-state friction. The results show that the after-slips at the VS barrier control the stress interaction and synchronization; hence, the barrier strength and size are the most important parameters. The static stress transfer can lead to immature ruptures that arrest within the VW asperity, adding complexity to failure times. The asperity size appears insignificant, challenging previous theories linking barrier efficiency to the asperity-barrier size ratios. Such discrepancy suggests that slip type, e.g., slip-pulse or crack-growth, influences the long-term failure time distribution. Even though the state evolution (aging and slip laws) for …

Authors

Eyüp Sopaci,Atilla Arda Ozacar

Journal

Authorea Preprints

Publish By

Authorea

Publish Date

2023/9/11

Impact of 2019 Mw 5.8 Marmara Sea Earthquake on the seismic cycle of locked North Anatolian Fault segment

The Mw5. 8 earthquake in the Marmara Sea west of the locked segment of the North Anatolian Fault sparked a debate on whether this event may trigger or advance the expected large (Mw> 7) earthquake close to Istanbul in time. Its potential effect on the major earthquake cycle is analyzed using rate-and-state friction (RSF) dependent spring-slider models by considering miscellaneous views of friction and different simulation strategies. Dynamic and static effects are simulated using recorded seismic waveforms and computed static stress change. Results indicated that this moderate earthquake cannot produce instant triggering on the locked fault segment but can advance the failure time noticeably. Simulations display no sensitivity to the inertial damping term; thus, quasi-dynamic and full-dynamic approaches agree. On the other hand, strong brittle-ductile coupling, smaller asperity size, and reduced clamping due …

Authors

Eyüp Sopacı,A Arda Özacar

Journal

Tectonophysics

Publish By

Elsevier

Publish Date

2023/7/20

Fault Based Tsunami Generation and Hazard Analysis: A Probabilistic Study for Aegean Coasts of Türkiye

The coasts of Türkiye are vulnerable to tsunami hazards due to the intensive use of coastal areas and the activity of faults in the surrounding seas. The Samos-İzmir earthquake occurred on October 30, 2020, followed by a tsunami that affected the Sığacık Bay revealed this fact once again, demonstrating the importance of accurately modeling the tsunami hazard across the country. Probabilistic Tsunami Hazard Assessment (PTHA) results for various coastal engineering parameters (ie, tsunami wave height, tsunami inundation distance) constitute one of the essential inputs of performance-based tsunami risk analysis. The TSUMAPS-NEAM project that ended in 2018 was one of the studies following the probabilistic approach for the Northeast Atlantic, Mediterranean, and connected seas (Basili et al. 2021). The primary objective of this study which is constructed within the TUBITAK (Scientific and Technological …

Authors

Gozde Guney Dogan,Ahmet Cevdet Yalciner,Arda Ozacar,Zeynep Gulerce,Duygu Tufekci-Enginar,Mehmet Lutfi Suzen,Onur Kanun,Onur Pekcan,Semih Yucemen

Journal

EGU General Assembly Conference Abstracts

Publish Date

2023/5

A New Vs30 Prediction Strategy Taking Topography, Geology, Terrain and Water Saturation into Account: Application to Türkiye and California

The time averaged shear wave velocity of the top 30 meters (Vs30) is the most widely used parameter for the geotechnical characterization of site conditions. However, the spatial availability of Vs30 observations are rather limited except specific areas where conducted micro-zonation studies include closely spaced measurements suitable for assessment of earthquake site effects. In order to infer Vs30, global models use slope or morphological terrain classes as proxies. In a regional scale, these proxies are commonly combined with geologic and geotechnical data to improve the accuracy of Vs30 predictions. So far, a region specific Vs30 model that would aid seismic hazard assessments is not yet constructed for Türkiye and its near vicinity. In this study, a new Vs30 prediction strategy is developed using data from Türkiye and California, and its performance is compared with others. At first, Vs30 measurements are …

Authors

Hakan Bora Okay,Atilla Arda Özacar

Journal

EGU General Assembly Conference Abstracts

Publish Date

2023/5

Fault Based Tsunami Generation and Hazard Analysis: A Probabilistic Study for Aegean Coasts of Türkiye

The coasts of Türkiye are vulnerable to tsunami hazards due to the intensive use of coastal areas and the activity of faults in the surrounding seas. The Samos-İzmir earthquake occurred on October 30, 2020, followed by a tsunami that affected the Sığacık Bay revealed this fact once again, demonstrating the importance of accurately modeling the tsunami hazard across the country. Probabilistic Tsunami Hazard Assessment (PTHA) results for various coastal engineering parameters (ie, tsunami wave height, tsunami inundation distance) constitute one of the essential inputs of performance-based tsunami risk analysis. The TSUMAPS-NEAM project that ended in 2018 was one of the studies following the probabilistic approach for the Northeast Atlantic, Mediterranean, and connected seas (Basili et al. 2021). The primary objective of this study which is constructed within the TUBITAK (Scientific and Technological …

Authors

Gozde Guney Dogan,Ahmet Cevdet Yalciner,Arda Ozacar,Zeynep Gulerce,Duygu Tufekci-Enginar,Mehmet Lutfi Suzen,Onur Kanun,Onur Pekcan,Semih Yucemen

Publish By

Copernicus Meetings

Publish Date

2023/2/22

Transient signal-based quantification of earthquake triggering effects on nearby faults using rate and state friction

Both numerical simulations and observational pieces of evidence suggest that the earthquake triggering mechanism depends non-linearly on time. The rate and state friction (RSF) demonstrate these dependencies with a changing weight of healing and weakening terms during its state's evolution. A clock advance due to a nearby rupture using the RSF models either agrees well with the Coulomb's static failure during the fault healing stage or becomes highly susceptible to velocity changes when the failure is imminent. Here we aim to formulate an analytical relation for earthquake triggering effects on nearby faults using transient signals. The dynamic mechanical weakening on the fault interface is quantified as a function of a transient oscillatory signal's peak ground velocity (PGV) and peak spectral frequency (PSF), elastic properties of the fault, and different state weakening terms. So far, the tested numerical …

Authors

Eyüp Sopacı,A Arda Özacar

Journal

EGU General Assembly Conference Abstracts

Publish Date

2023/5

Revealing the Deformation of SW Anatolia (Turkey) by Anisotropy of Magnetic Susceptibility (AMS) Data

Convergence between the Eurasian and the African plates in the West Anatolian-Aegean region results in a trench retreat due to slab roll-back and tearing of the subducted African lithosphere. The upper plate response of this process gave way to back-arc extension in the region. In this context, we have conducted a very rigorous AMS study on the Neogene units in SW Anatolia to unravel the style and amounts of deformation. For this purpose, from 83 sites in 11 structurally homogeneous domains, 1680 paleomagnetic samples were analyzed. Obtained results are used to determine principal strain directions to unravel overall deformation styles and amounts in the region. The results have shown that AMS is related to the tectonic deformation, which facilitated that the AMS directions correspond to cumulative principal strains. Maximum susceptibility is parallel to the major extension (k), minimum susceptibility (k) corresponds to compaction after deposition, almost always normal to the bedding plane. The intermediate axis (k) found to be parallel to a second extension direction that the region has been under the control of multi-directional extension during Neogene. Two mean anisotropy directions are identified. These are Oligocene-Middle Miocene NW-SE, and Late Miocene-Pliocene NE-SW directed extension. The mean anisotropy directions are generally parallel or perpendicular to the general strikes of the normal faults. The results have shown that the deformation in the region resembles to differentially stretched rubber sheet under the influence of SW directed extension exerted by the southwards retreating Eastern Mediterranean subduction …

Authors

Nuretdin Kaymakcı,Murat Özkaptan,Erhan Gülyüz,Bora Uzel,Cor Langereis,A Arda Ozacar

Journal

Authorea Preprints

Publish By

Authorea

Publish Date

2022/11/23

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