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Major strike-slip fault systems on Earth, like the North Anatolian Fault (NAF), play an important role in accommodating plate motion, but surprisingly little is known about how such structures evolve through space and time. Along the central sector of the NAF in the Central Pontides, transpression and crustal thickening along the northward restraining bend of the fault are thought to have generated rock-uplift rates of 0.2–0.3 km/Myr since at least 400 ka based on Quaternary marine and river terraces, while data from low-temperature thermochronology suggest that an enhanced exhumation phase occurred within the last 11 Myr. However, the precise onset of this faster uplift phase, which likely reflects deformation associated with the development of the central sector of the NAF, is poorly constrained. Here we define the spatiotemporal pattern of rock-uplift rates within the Central Pontides over the last ∼10 Myr by performing linear inversions of 19 river profiles that drain the northern margin of the Central Pontides, from the Sinop Range to the Black Sea. We use 21 new 10Be-derived basin-average denudation rates to calibrate an erodibility parameter, which we use to convert our χ -transformed river profiles into rock-uplift histories. Our results document an increase in rock-uplift rates after 10 Ma, with peak rates of ∼0.15–0.25 km/Myr occurring between 4 and 2 Ma. Moreover, the spatiotemporal pattern of uplift suggests that faster rock uplift started in the eastern part of the Sinop Range and migrated westward over a period of ca. 2 to 2.5 Myr, which we relate to the westward propagation of the NAF through this sector at a rate of 74 ± 13 km/Myr. In the context of previously published constraints on the westward propagation of the NAF starting in eastern Turkey at ∼12 Ma, our results suggest differences in fault-propagation rates that coincide with differences in the orientation of the NAF relative to plate-convergence velocity vectors. Fault segments with higher obliquity appear to have propagated at rates up to 2-fold slower than those oriented more parallel to the plate-convergence vector. • Rock-uplift history of Central Pontides from river linear inversions. • The uplift event after 10 Ma dates the arrival of the North Anatolian Fault (NAF). • The uplift migration provides the propagation rate of the NAF central segment. • New insights about the propagation history of all the NAF segments. • Linkage between NAF propagation rates and plate convergence directions. [ABSTRACT FROM AUTHOR]

The goal of this study is to establish a workflow for the re-interpretation of almost depleted fields targeting the long-term sustainable oil production; in particular, for the oil fields in Turkey and the neighboring Middle Eastern countries located on the fold and thrust belts of the Zagros Mountains. It also fills some of the gaps in our understanding of the northern part of the Arabian Platform by describing the seismic characteristics of the Cretaceous reservoirs that were deposited during the Aptian to Turonian. The Katin-Barbes oil field (KBOF) in SE-Turkey was used as a case study. In this area, 3D seismic data were used for structural interpretation and re-modeling of Cretaceous carbonates sedimented in the complex tectonic region. The well logs from 55 wells in the field were used to create a compilation of formation tops and were used as reference points for two separate sets of 3-D seismic data, acquired in 1991 and 2017. The quality of seismic data was improved with interpretation filters. The structural model was obtained by using various qualifiers from the seismic cubes and seismic facies changes were identified by analyzing a number of seismic attributes. Therefore, seismic data and velocities from the borehole measurements were combined to form a velocity model in building a structural model. Seismic attributes and well logs were used to create a porosity model. Consequently, top and base of two reservoir units; the Derdere and Sabunsuyu Formations have been clarified and re-defined, and potential new well locations were identified. Depending on the results of this investigation, 9 new wells were drilled in the potential areas in the KBOF, recently. Except the last one drilled on the NE boundary of the northern block, all wells have been completed as the "oil producing wells" and top of the reservoir units were encountered at almost the same depths in our depth model. Therefore, results and proposed methods in this research are confirmed by the real, borehole data. This research will be an examplary study for the re-evaluation of older and/or almost depleted oil fields, either in Turkey or in the other Middle Eastern countries. • This study indicates the seismic characteristics of Aptian to Turonian units on the N of Arabian Platform. • Some innovative steps were indicated in an old HC field after new seismic data. • New drillable locations were determined in this old oil field, KBOF. • The goal of this preliminary study is to establish a framework for long-term oil production in the almost depleted fields. [ABSTRACT FROM AUTHOR]

• The first 3-D Neogene velocity-depth model of the Gulf of İzmir obtained up to 1.7 km depth. • The Miocene acoustic basement displays asymmetrical upper surface morphology with ridges and basins. • Four Plio-Quaternary stratigraphic units fill the basement with varying thicknesses. • Lateral and vertical velocity anomalies documented within the Plio-Quaternary deposits. • The low-velocity zones are interrupted laterally by the high-velocity zones corresponding to squeezed sediments of the Karaburun Fault Zone. • The fault-controlled velocity anomalies suggest gas/fluid and heat transfer along faults from a deeper source. There are basins with proven hydrocarbon and geothermal sources across western Anatolia. Only a few moderate-scale tomography studies investigate their velocity structure and stratigraphical architecture. We present the first 3-D Neogene velocity-depth model of the Gulf of İzmir down to ∼1.7 km. The aim is displaying a better portrait of the 3-D stratigraphical architecture, velocity structure of the Gulf of İzmir, and constitute a solid foundation for future studies. We provide the first 3-D view of the complex Late-Miocene basement topography representing an unconformity surface. It consists of basins and ridges separating the Miocene basement (SSU3) and overlying Plio-Quaternary deposits (SSU2 and SSU1). Four N S oriented volcanic ridges accommodate offshore Uzun Island, Karaburun, and Foça. They border a basin with a thickness of ∼720 m in the mid-central and a deeper one with ∼1400 m in the northernmost sector of the gulf. The 3-D P-wave traveltime tomography results indicate prominent lateral and vertical velocity variations at different depths (∼300–800 m). The low-velocity zones (1600 ≤ Vp ≤ 1850 m/s) are interrupted laterally by the high-velocity zones (2150 ≤ Vp ≤ 2350 m/s) that corresponds to the squeezed sediments within Plio-Quaternary basins deformed by the N S trending strike-slip faults of Karaburun Fault Zone. The same faults also deform the volcanic basement highs identified by the high velocities (>2600 m/s). The thick depocenter with low-velocity anomalies in the outer gulf suggests the gas/fluid containing sediments. Their controlling faults are likely responsible for the circulation of gas/fluid and heat transfer from a deeper source making the region target for exploration activities. [ABSTRACT FROM AUTHOR]

• Focus on reflection amplitudes for studying the effect of a CO 2 -saturated fracture. • S-wave velocity is more sensitive to changes in pore pressure than P -wave velocity. • Stress-dependency of the P-wave velocity increases with temperature. • Temperature-dependency of the P-wave velocity increases with reducing stress. As part of a seismic monitoring project in a geothermal field, where the feasibility of re-injection and storage of produced CO 2 is being investigated, a P- and S-wave seismic velocity characterisation study was carried out. The effect of axial and radial (up to 42 MPa) stress, pore pressure (up to 17 MPa), pore fluid (100% brine or supercritical CO 2) and temperature (21–100 °C) on seismic properties were studied in the laboratory for the two main reservoir formations at the Kızıldere geothermal reservoir. Each (un)confined compressive strength test performed revealed a similar trend: rapidly increasing velocity at low stresses followed by a more moderate increase at higher stresses. The data implied that the stress-dependency of the velocity increased with temperature. Increasing temperatures resulted in decreasing P-wave velocities due to mineral thermal expansion. This temperature-dependency increased with reducing stress levels. The S-wave velocity seems to be more sensitive to changes in pore pressure than the P-wave velocity. On the other hand, the S-wave velocity is less affected by an increasing axial stress compared to the P-wave velocity. By performing multiple nonlinear regression on the velocity dataset, related to a brine-saturated fractured marble, second-degree polynomial trends were found for the P- and S-wave velocity, as a function of temperature, axial stress, and pore pressure, that can potentially be used for predicting velocities at Kızıldere, or other similar, geothermal site(s). For distinguishing between a 100% brine-saturated versus a fully supercritical CO 2 -saturated fracture, the arrival times of the first arrivals were too close to each other to allow their utilization. The fracture aperture was too small compared to the wavelength of the source signal. However, differences in P- and S-wave amplitudes of the first arrivals were seen, where the supercritical CO 2 -saturated crack revealed consistently lower peak and trough amplitudes compared to the brine-saturated scenario. [ABSTRACT FROM AUTHOR]

In this study, two-dimensional electrical resistivity tomography (ERT) and one-dimensional multi-channel surface waves analysis (MASW) methods conducted on the surface were used to examine the location of a creek drainage tunnel constructed for the campus road and its relationship with the surrounding geological units in the Kocaeli University campus site results are presented. As it is known, geophysical studies conducted from the surface are generally applied in terms of feasibility and to determine the geological problems in the route of tunnels before the tunnel construction. Geophysical studies revealing the tunnel and associated underground characteristics in a completed tunnel are very limited. Therefore, this study aims to describe the general character of the tunnel and its surroundings in the subsurface, with measurements made by using surface geophysical methods (ERT and MASW) over the tunnel. In the ERT studies, four different arrays were examined to resolve this problem. These are, respectively; Wenner-alpha, −beta, −gamma and Schlumberger. On the tunnel problem here, a possible model similar to the geological structure dominated by the marl layers in the region was synthetically designed with these arrays. In this study, the effectiveness of all these arrays against the problem was tested. Then, by evaluating the data collected from the field, the appropriate array testing was examined for the real problem. In the context of these studies, the results of the MASW studies conducted between 24 and 46 m of the ERT line were compared with the ERT data to reveal the geological phenomena in the tunnel and its vicinity. The resistivity values (ρ) in the 2D electrical resistivity models obtained from ERT have values of ρ > 80 Ωm in the tunnel section and ρ < 55 Ωm in the materials surrounding the tunnel. The medium-high resistivity values characterize the earthfill layer. In MASW studies, it was revealed that shear wave velocity (Vs) values in the tunnel were lower (<250 m/s) and higher (250 and 500 m/s) in the materials surrounding the tunnel. Deep below the tunnel and in the northeastern part of the field, the ground has relatively higher shear wave velocities (Vs > 400 m/s). Because of the comparison of ERT and MASW results, it was revealed that both methods showed good agreement in terms of tunnel depth and size. While the different sequences used in the ERT study generally provided successful results in identifying the tunnel, different model results were revealed in the surrounding earthfill, weathered and intact marl layers. The MASW results, on the other hand, gave more successful results than expected in determining the location of the tunnel. Because of the comparison of both methods, it has been shown that the use of the ERT and MASW methods together can provide more effective results in examining the location of buried tunnels and their relationship with the surrounding geological units. • Application of geophysical methods on the tunnel with known overall properties. • Combined application of electrical resistivity tomography and multichannel analysis of surface waves methods. • Determining a tunnel buried at a depth close to the surface in terms of location, shape, shear velocity and resistivity. • Application on both synthetic and field data set. [ABSTRACT FROM AUTHOR]

Vertical movements of the solid Earth surface reflect crustal deformation and deep mantle related phenomena. For Holocene times, coastlines displaced from the present mean sea-level are often used together with past relative sea-level (RSL) prediction models to decipher the vertical deformational field. Along the coastline from southwest Turkey eastward to Israel and Cyprus, field data that constrain Holocene vertical movements are already published, leaving a gap only along the Mediterranean coast of the Central Anatolian Plateau (CAP). Based on new field observations between Alanya and Adana (Mersin, southern Turkey), together with AMS 14C dating, we fill that gap, allowing for the construction of a continuous overview of Holocene vertical differential movements along the Eastern Mediterranean coast. We apply the most recent Glacial Isostatic Adjustment (GIA) models to correct for the glacio-hydro isostatic component of the RSL. Different solutions from the ICE-6G(VM5a) and ICE-7G(VM7) models (developed by W.R. Peltier and co-workers at the Toronto University), and a GIA model developed by K. Lambeck and collaborators at the Australian National University, have been applied to 200 middle-to-late Holocene RSL markers. Starting from southwest Turkey, we find subsidence between −0.9 mm/yr and − 2.3 mm/yr, corroborating estimates from previous studies. Velocities from the new markers along the CAP Mediterranean coast are positive, ranging between 0.9 and 1.5 mm/yr. These two first blocks are separated by a sharp velocity jump, occurring along the Isparta Angle Fault System one. Such high vertical velocities for the CAP southern margin were predicted by recently published papers that report a rapid uplift phase that peaked during themiddle to late Pleistocene. Moving to the east, velocities are also positive, from 0.2 to 0.6 mm/yr along the coast between the Hatay Gulf and southern Lebanon. The highly variable velocity along the Lebanese sector is likely due to co-seismic deformation along the Lebanese Restraining Bend (LRB) faults. To the south, in contrast, the Israeli coast shows stability, according to some unique archaeological RSL markers named piscinae, whereas other markers indicate slow subsidence (−0.2 mm/yr on average). Hence, another velocity jump of at least 0.5 mm/yr is recognizable between Israel and Lebanon. This jump is probably associated with mapped, active tectonic structures. In Northern Cyprus, the only Holocene sea-level marker confirms the near zero vertical velocity values already obtained for the MIS 5e marine terrace. Therefore, a vertical velocity jump occurs between stable Northern Cyprus and the uplifting CAP southern margin, although they occur on the same overriding plate of the Eastern Mediterranean subduction system. High-angle normal faults at the northern margin of the Adana-Cilicia Basin could explain these strongly distinct late Holocene vertical velocity fields. These results depict a complex framework of independently moving crustal blocks, with kinematic separation along well-known regional fault zones. The drivers of the block movements could be related either to regional tectonics, as it is probably the case for the LRB coast, or to mantle dynamics, such as for the uplifting Turkish sector, where deeper processes should be considered. [ABSTRACT FROM AUTHOR]

Multi-frequency P- and S- wave attenuation tomography models of Lake Van area (East Anatolia) have been obtained by estimating coda-normalized wave spectra of 3027 local earthquakes (2.0 < Mw < 7.1). The 6998 waveforms sampled from surface to a depth of 25 km, and were recorded from 2004 to 2020 at seven broadband, three-component digital seismic stations operated by Kandilli Observatory and Earthquake Research Institute (KOERI). We adopted a two-point ray-bending method to trace rays in a 3-D velocity model. We applied the coda normalization (CN) method to P - and S -wave data sets. We inverted the spectral data with a multiple resolution seismic attenuation (MuRAT) approach to obtain final tomographic models. On average, high (low) attenuation corresponds to low (high) velocity anomalies. The P- and S- wave attenuation contrasts delimit four well-known geological zones. High frequency-short wavelength attenuation contrasts constrain the 5-km-deep zone of interaction between magma and sediments within the Lake Van basin. Low frequency-long wavelength attenuation anomalies mark the central section of Lake Van between depths of 10 km and 20 km. This zone coincides with a rigid stable shear zone overlying a possible weak-ductile lower crust, interpreted as a detachment. Both low (5–15 km depth) and high attenuation (>20 km) anomalies mark the area of maximum seismic energy release during the Van event. Their contrast highlights the maximum seismogenetic depth above weak-warm, unstable materials. High attenuation in the SE-part of the Lake Van area coincides with a large hydrothermal and/or magmatic folding-overthrusting, interpreted as a suture-metamorphic complex between depths of 10–15 km. Other minor high-attenuation zones deeper than 5 km focus on complex shear zones in the area damaged by the Van event. The paired attenuation structure of the Lake Van area appears linked to multiple tectonic processes of crust-magma interaction better constrains subsurface segmentation structures and differential deformation types at upper-middle crustal depths. [Display omitted] • The attenuation contrasts at Lake Van delimit distinct geological units. • Shallower short wavelength attenuation revealed weak unstable shear zones. • Deeper long wavelength attenuation marked rigid stable shear zones. • This study better constrained crustal segmentation and differential deformation types. [ABSTRACT FROM AUTHOR]

Assessment of potential seismic risk and losses in urban environments is necessary for several purposes ranging from risk mitigation to city and regional planning. It is well known that loss estimation should be performed within an interdisciplinary setting involving earth sciences and engineering. Field experience from recent events worldwide shows that the spatial variability of seismic damage is due to the combined effects of earthquake source properties, local site conditions and structural characteristics. In this study, a scenario-based multi-input damage estimation framework in an urban region was utilized for the Gaziantep city center (southeastern Turkey) that is located in a region of high seismic hazard with no large events in the instrumental era. Initially, a thorough geological and seismo-tectonic assessment of the area was performed followed by estimation of two critical scenario events with moment magnitude (Mw) of 6.5 and 6.6 on nearby active faults. Then, a regional velocity model was compiled from regressions of existing regional geotechnical and seismic data in terms of the V S30 parameter. As the next step, field surveys for the assessment and classification of buildings in the study area were performed followed by vulnerability analyses. As the last step, the mean damage ratios were computed at 198 neighborhoods within the city center. The results indicate not only a high hazard but also high risk in the Gaziantep area due to the combination of close proximity to the faults along with local site effects and building fragilities. • Identification of seismic source characteristics of Gaziantep city, Turkey. • Development of regional seismic velocity model. • Simulation of ground motion records for the selected scenario earthquakes. • Identification of building stock characteristics in the study area and derivation of seismic fragility curves for each building typology. • Estimation of regional seismic damage. [ABSTRACT FROM AUTHOR]

Abstract: Atmospheric deposition is a significant pollution source leading to contamination of remote and clean sites, surface waters and soils. Since persistent organic pollutants (POPs) stay in atmosphere without any degradation, they can be transported and deposited to clean surfaces. Organochlorine pesticides are an important group of POPs which have toxic and harmful effects to living organisms and environment. Therefore, atmospheric deposition levels and characteristics are of importance to determine the pollution quantity of water and soil surfaces in terms of POPs. This study reports the distribution quantities of atmospheric deposition including bulk, dry, wet and air–water exchange of particle and gas phase OCPs as a result of 1-year sampling campaign. Atmospheric deposition distribution showed that the main mechanism for OCPs deposition is wet processes with percentage of 69 of total deposition. OCP compounds' deposition varied according to atmospheric concentration and deposition mechanism. HCH compounds were dominant pesticide species for all deposition mechanisms. HCH deposition constituted the 65% of Σ10OCPs. [Copyright &y& Elsevier]

Highlights: [•] New Moho depth map is presented. [•] Crustal thickness is varying between 24 and 48km. [•] The thinnest crust observed at the western coast of Anatolia. [•] The thickest crust observed at the eastern Anatolia. [•] Uppermost mantle S-wave speed is lower than world average. [ABSTRACT FROM AUTHOR]

Abstract: Space-based tectonic studies on the western part of the North Anatolian Fault Zone (NAFZ) have been conducted over two decades. After the August 17, 1999, Izmit earthquake (M w =7.4), this region attracted greater scientific interest, and the collected data became more valuable. The Geodesy Department of the Kandilli Observatory and Earthquake Research Institute (KOERI) at Bogazici University established three micro-geodetic networks to the east of Akyazi, east of Iznik, and west of Lake Sapanca in the eastern part of the Marmara region; GPS data have been continually collected at these locations since 1994. The NAFZ branches out in the western part of the Marmara region and extends up to the Aegean Sea. Segments of the fault passing through the Marmara Sea are considered active, and this has increased concern regarding imminent earthquakes. Conventional geodetic measurements made between 1990 and 1994 are not sufficient for monitoring small movements. However, GPS has played a very important role in detecting such deformations in the area after 1994. The Iznik network, with 10 points, is bilaterally located on the Iznik-Mekece fault. Six years of GPS data for 2004–2010 collected for the monitoring of crustal deformation showed that the Iznik-Mekece fault segment moves westward at about 22±1mm/yr with respect to the Eurasia fixed reference frame. The GPS observations show that there is no strain accumulation in the area. [Copyright &y& Elsevier]

Abstract: We present results on imaging contrast of seismic velocities across the Mudurnu segment of the North Anatolian Fault Zone (NAFZ) in northwestern Turkey with polarization analysis of early P waveforms generated by near-fault seismicity and recorded by near-fault stations. The analysis uses changes in motion polarity from fault–normal to source–receiver directions to identify early-arriving fault zone head waves on the slow side of the fault, and measure the arrival times of the head and direct P waves. The moveout between the head and direct waves with increasing source–receiver distance along the fault provides an estimate of the average contrast of seismic velocities across the fault. The results indicate that the average contrast of P wave velocities across the Mudurnu segment of the NAFZ is at least 6%, with the south block being the faster side. The findings provide a basis for deriving improved event locations, focal mechanisms and estimated shaking hazard associated with earthquakes on the fault. The analysis technique can be used in other fault zones monitored with sparse seismic instrumentation. [Copyright &y& Elsevier]

Abstract: Wet and dry deposition samples were collected along with the ambient air samples between September 2008 and June 2009 in an urban site, BUTAL, Turkey. A modified deposition sampler was used for dry and wet periods. Average dissolved and particle phase wet deposition flux values were determined to be 7.4±7.3μg/m2 day and 21±30μg/m2 day, respectively. The highest PAH wet fluxes were observed in the winter and fall seasons. Dissolved and particle phase rainwater concentrations of PAHs were 290ng/L and 665ng/L. The average of total (particle+gas) atmospheric concentration of ∑12PAH was 130±160ng/m3. In general, percentages of PAHs with five or more aromatic rings were bigger in particle phase in air. Average washout ratios of PAH compounds were determined 8.97×105 and 8.52×105 for gas and particle phase, respectively. Gas phase washout ratios of high molecular weight PAHs were greater than the lower molecular weight PAHs. [Copyright &y& Elsevier]

Abstract: The seismicity of the northern part of Turkey is mainly controlled by the North Anatolian Fault zone (NAFZ). The NAFZ is one of the world''s most active seismic zones, and has produced destructive earthquakes and related hazards in the northern region of Turkey. Several earthquakes and earthquake-related hazards have occurred along different segments of this fault zone in the recent past. The study area, Erbaa town, is located along the eastern segment of North Anatolian Fault Zone (NAFZ) and is one of the largest towns of Tokat Province in the Middle Black Sea Region of Turkey. The center of Erbaa is located on the left embankment of the Kelkit River. After the disastrous 1942 (Ms =7.2) and 1943 (Ms =7.6) earthquakes, the settlement was shifted southwards. As a part of a seismic microzonation study of the Erbaa area, shear wave velocity (Vs) values of the geological units exposed in this area were required for site response analyses. The geological units in the study area consist mainly of alluvial and Pliocene units. These layers were evaluated on the basis of drilling, in-situ (SPT, SCPTU and SPT-based uphole) and laboratory testing. In this study, empirical correlations between shear wave velocity (Vs) and standard penetration test blow counts (SPT-N) were considered in order to define shear wave velocity profiles for the study area. The relationships between shear wave velocity, Standard Penetration Test (SPT) blow-counts and the soil properties were evaluated as functions of depth. SPT-based uphole tests were performed to measure shear wave velocity during drilling operations in some of the borings. The SPT-based Vs values were computed with different empirical formulas and compared with the measured SPT–based uphole Vs measurements. The empirical correlations were found to require modification to provide the best correlation for this site. The depth factor was considered during the development of new empirical equations. Therefore, a site-specific formula was proposed in order to obtain Vs profiles for all layers in the study area. [Copyright &y& Elsevier]

Abstract: The atmospheric concentrations and dry deposition of carbazole were measured to present the temporal changes, gas/particle partitioning and magnitude of fluxes. Atmospheric samples were collected from July 2004 to May 2005 at four different sites in Bursa, Turkey. The average total (gas and particulate) carbazole concentrations were 7.6±9.9ngm−3 in Gulbahce (Residential), 1.1±1.2ngm−3 in BUTAL (Traffic), 3.3±5.0ngm−3 in BOID (Industrial), and 1.2±0.7ngm−3 in the Uludag University Campus (UU) (Suburban). Experimental gas/particle partition coefficient (K p) was determined using the study results and compared with K p values calculated from octanol–air and soot–air+octanol partitioning models. Total dry deposition fluxes of carbazole were 290±484ngm−2 d−1 in BUTAL and 72±67ngm−2 d−1 in the UU Campus. Particulate phase dry deposition velocities were 0.81±0.78cms−1 and 0.90±1.53cms−1 for BUTAL and the UU Campus, respectively. On the other hand, gas-phase mass transfer coefficients were calculated to be 0.34±0.29cms−1 and 0.26±0.17cms−1 for BUTAL and the UU Campus, respectively. [Copyright &y& Elsevier]

Abstract: Regional site conditions relevant for seismic hazard studies can be derived from various geologic, seismologic, and geotechnical sources. In this study, site conditions are derived for the Ankara Basin in Turkey by merging in-situ seismic measurements of dynamic properties, geologic information, and some geotechnical boring information. Field seismic refraction surveys were performed at 259 sites in the project area to classify and characterize Plio–Pleistocene fluvial deposits and Quaternary alluvial and terrace deposits. The shear-wave velocity profiles of the near-surface geologic units are used to characterize site classes according to the International Building Code [International Code Council, ICC. International Building Code. Structural and fire- and life-safety provisions (seismic, wind, accessibility, egress, occupancy and roof codes), 2006. Whittier, CA.] and the Turkish Seismic Code [Ministry of Public Works and Settlement, 1998. Turkish Seismic Code, Specification for Structures to be Built in Disaster Areas, Ankara, Turkey], and to develop a regional model for the average shear-wave velocity in the top 30m. The resulting maps of site class indicate that the classification system for the Turkish Seismic Code results in a significant portion of the Ankara Basin being classified as Z4, the softest site class. The International Building Code site classification system results in most of the Ankara Basin being classified as D, stiff soil. These differences are caused by the Turkish Seismic Code incorporating information from only the surface layer, while the International Building Code incorporates information from the top 30m. [Copyright &y& Elsevier]

Abstract: Soil and atmospheric concentrations, dry deposition and soil-air gas exchange of organochlorine pesticides (OCPs) were investigated at an industrial site in Aliaga, Izmir, Turkey. Current-use pesticides, endosulfan and chlorpyrifos, had the highest atmospheric levels in summer and winter. Summertime total (gas+particle) OCP concentrations in air were higher, probably due to increased volatilization at higher temperatures and seasonal local/regional applications of current-use pesticides. Particle deposition fluxes were generally higher in summer than in winter. Overall average dry particle deposition velocity for all the OCPs was 4.9±4.1cm s−1 (average±SD). ΣDDXs (sum of p,p′-DDT, p,p′-DDD, and p,p′-DDE) were the most abundant OCPs in Aliaga soils (n =48), probably due to their heavy historical use and persistence. Calculated fugacity ratios and average net gas fluxes across the soil-air interface indicated volatilization for α-CHL, γ-CHL, heptachlorepoxide, cis-nonachlor, trans-nonachlor, and p,p′-DDT in summer, and for α-CHL, γ-CHL, trans-nonachlor, endosulfan sulfate, and p,p′-DDT in winter. For the remaining OCPs, soil acted as a sink during both seasons. Comparison of the determined fluxes showed that dry particle, gas-phase, and wet deposition are significant OCP input mechanisms to the soil in the study area. [Copyright &y& Elsevier]

Abstract: This study investigates an application of genetic programming (GP) for the prediction of peak ground acceleration (PGA) using strong-ground-motion data from Turkey. The input variables in the developed GP model are the average shear-wave velocity, earthquake source to site distance and earthquake magnitude, and the output is the PGA values. The proposed GP model is based on the most reliable database compiled for earthquakes in Turkey. The results show that the consistency between the observed PGA values and the predicted ones by the GP model yields relatively high correlation coefficients (R 2=0.75). The proposed model is also compared with an existing attenuation relationship and found to be more accurate. [Copyright &y& Elsevier]

Abstract: Waveforms of 50 teleseismic receiver functions and dispersion curves have been used to invert jointly for the 1D average crust and uppermost mantle seismic structure beneath GEOFON station ISP. The surface wave (Rayleigh and Love) dispersion curves were adopted from an earlier study and greatly help to stabilize the inversions by alleviating the deficiencies of inverting the receiver functions alone. The teleseismic receiver functions had a backazimuth distribution from which three stacks were created. All the stacks resulted in compatible inversions. Nine different influence factors ranging between 0.1 and 0.9 were employed and the influence factors around 0.5 were preferred for producing a reasonable seismic structure to represent the geology under station ISP. Three distinct crustal depth ranges are identified based on the inverted velocity-depth profile. The first corresponds to 0–5km where the velocity-depth profile has a positive gradient with an increase from 2.5kms−1 to 3.0kms−1. The second depth range is 5–10km and the velocity-depth profile shows a positive gradient between 3.0kms−1 and 3.20kms−1. A velocity jump from 3.20kms−1 to 3.62kms−1 tops the third depth range (10–20km), which is characterized by a constant velocity. There is another velocity drop at 20km depth from 3.62kms−1 to 3.40kms−1 and the low velocity therein is persistent down to 27.5km. Below this depth range, the shear velocity increases until 40km depth where the Moho discontinuity is estimated with Sn velocity of 4.4kms−1. In general, seismic velocities under SW Anatolia are considerably slower than those of the Preliminary Reference Earth Model (PREM). [Copyright &y& Elsevier]

Abstract: Single station seismic noise measurements were carried out at 192 sites in the western part of Istanbul, Turkey. This extensive survey allowed the fundamental resonance frequency of the sedimentary cover to be mapped, and identify areas prone to site amplification. The results are in good agreement with the geological distribution of sedimentary units, indicating a progressive decrease of the fundamental resonance frequencies from the northeastern part, where the bedrock outcrops, towards the southwestern side, where a thickness of some hundreds meters for the sedimentary cover is estimated. The particular distribution of fundamental resonance frequencies indicates that local amplification of the ground motion might play a significative role in explaining the anomalous damage distribution after the 17 August 1999 Kocaeli Earthquake. Furthermore, 2D array measurements of seismic noise were performed in the metropolitan area with the aim of obtaining a preliminary geophysical characterization of the different sedimentary covers. These measurements allow the estimation of the shear-wave velocity profile for some representative areas and the identification of the presence of strong impedance contrast responsible of seismic ground motion amplification. Comparison of a theoretical site response from an estimated S-wave velocity profile with an empirical one based on earthquake recordings strongly encourages the use of the low cost seismic noise techniques for the study of seismic site effects. [Copyright &y& Elsevier]

[Display omitted] • Use of measured data on the calculation of underwater acoustic channel capacity. • The effect of seasonal change on underwater acoustic channel capacity. • Effects to the underwater channel by the change in absorption losses and sound velocity with depth. Due to their chaotic nature, underwater communication channels contain many adverse factors affecting the communication link quality and its performance. These adverse effects directly affect the data transfer between the source and the receiver. Absorption loss, which is one of these adverse factors, depends on depth, temperature, salinity, pH, and speed of sound, as well as frequency, and it has direct impact on the bandwidth used by the system and the distance required for reliable communication. In this study, the effects of variation of temperature, salinity, depth, and sound velocity on the channel bandwidth, channel capacity, and transmission power of the channels formed in the underwater environment in Erdek/Turkey were examined. Within the scope of the study, estimations of the bandwidth, capacity and transmission power parameters were conducted by using temperature, salinity, and sound velocity data relative to the depth recorded between July 2018 and December 2018. Cylindrical, spherical, and practical propagation models are used to compute the propagation loss. In contrast to the studies performed in the literature regarding absorption loss calculations, instead of using only the frequency-dependent approach, realistic models were created by including the effect of changes in the underwater environment in the channel estimation calculations using measurement data. Simplified absorption loss parameters for absorption loss calculations are proposed in the study. It was observed that the channel estimated within the scope of the study are compatible with the outputs obtained from the analysis. [ABSTRACT FROM AUTHOR]

The aim of this study is to predict peak particle velocity level at a limestone quarry located in Istanbul, Turkey. The ground vibration components were measured for 73 blast events during the bench blast optimization studies during a long period. In blasting operations; ANFO (blasting agent), gelatine dynamite (priming) and NONEL detonators (firing) were used as explosives at this site. Parameters of scaled distance (charge quantity per delay and the distance between the source and the station) were recorded carefully and the ground vibration components were measured by means of vibration monitors for every event. Then, the data pairs of scaled distance and particle velocity were analyzed. The equation of scaled distance extensively used in the literature was taken into consideration for the prediction of peak particle velocity. At the end of statistical evaluations, an empirical relationship with good correlation was established between peak particle velocity and scale distance for this site. The established relationship and the results of the study are presented. [Copyright &y& Elsevier]

Dry deposition samples were collected using a smooth surrogate surface at the Kaynaklar Campus of the Dokuz Eylul University in Izmir, Turkey. Concurrently ambient aerosol samples were collected. All samples were analyzed for anthropogenic and crustal trace elements. The average trace element concentrations and fluxes measured in this study were generally higher than those reported previously for urban and rural areas. The contribution of local terrestrial and anthropogenic sources were also investigated using enrichment factors (EFs) calculated relative to the local soil. Relatively lower EFs for ambient samples and high ambient concentrations indicated that the local soil was polluted and contributed significantly to ambient trace element concentrations. Deposition samples had higher EFs than the air samples. The EF sequences of trace elements were also different for deposition and ambient samples, probably due to the fact they have different mass median diameters and deposition velocities. The overall dry deposition velocities for trace elements calculated by dividing the particulate fluxes measured with the surrogate surfaces by ambient concentrations ranged from 0.6 (Al) to 6.2 cm s−1 (Fe). The agreement between the experimental dry deposition velocities determined in this study and the previously reported ones using similar techniques for trace elements was good. [Copyright &y& Elsevier]

The northwestern part of Turkey is a significant area for its location on the accretionary region of several micro-continents and blocks. Therefore, there are several suture zones and western segments of the "North Anatolian Fault Zone" are scattered in the study area. Due to trans -tensional stresses, there are several pull-apart basins and/or depressions within the fault zone in the study area. As a consequence, it is also possible to observe magmatic intrusions into the fault segments. All these events and magmatic emplacements in the tectonic framework provide significant magnetic anomalies throughout the region. In this study, geothermal potential of the region is investigated based on the spectral analysis of the magnetic data, together with the seismic velocity (VP) distribution in the area using the log-linear relationship between the seismic velocity and the radiogenic heat production. Although two regions are emerging in the Curie Point Depth (CPD) and geothermal gradient maps, only one anomalous area from Bursa to Tekirdag may be considered as a promising region for the further geothermal energy exploration in the heat-flow maps prepared according to two different thermal conductivity coefficients. Seismic velocities are also low in this anomalous region decreasing down to 6.40 km/s around the shoreline of Tekirdag. Heat-flow values are increasing up to 110 mW/m2 in this particular area where the CPDs are around 14 km. [Display omitted] • CPDs are in the range of 14–16 km between Bursa and Tekirdag, in the Marmara region. • Geothermal gradient anomaly around Tekirdag is represented with 39 °C/km contours. • Seismic velocities decreased down to 6.40 km/s in this thermally anomalous area. • Heat-flows are around 100–110 for thermal conductivity coefficients (2.5 and 2.7). • Radiogenic heat production increases up to 0.36 (μ W m − 3 ) in the anomalous zone. [ABSTRACT FROM AUTHOR]

Mt. Hasan (3262 m) is the second highest stratovolcano in Central Anatolia, Turkey, and is considered active based on a ca. 9 ka explosive summit eruption that was arguably depicted in a Neolithic mural at the nearby Çatalhöyük archaeological site. Besides evidence for Holocene activity of Mt. Hasan, its eruptive chronostratigraphy and hazard potential remain poorly constrained. Here, we apply (U–Th)/He thermochronology in combination with U–Th–Pb crystallization ages (zircon double-dating), including a novel population-based approach to disequilibrium correction of (U–Th)/He data, in an attempt to determine the eruption ages of strategically sampled lavas and pyroclastic deposits and to refine the Late Pleistocene chronostratigraphy of Mt. Hasan. During the Late Pleistocene, Mt. Hasan erupted multiple interfingering andesitic lava flows along with block-and-ash-flows. Seven of these lava flows, typically the stratigraphically youngest in a particular segment around the two central vents of the volcano, yielded Late Pleistocene eruption ages between 91.9 ± 3.9 and 18.1 ± 2.4 ka (uncertainties stated at 1σ). An even younger block-and-ash-flow was deposited on the western flank of the volcano at 13.5 ± 1.5 ka, which together with a ca. 9 ka small-volume explosive summit eruption define the youngest activity at the main edifice of Mt. Hasan. Collectively, these data indicate a Late Pleistocene recurrence of at least one eruptive phase every ca. 5–15 ka. New volume estimates for the Quaternary edifice of ~130–180 km3 translate into an integrated long-term eruptive magma flux of ~0.3 km3/ka, which is just slightly higher than Late Pleistocene flux estimates based on lava flow geochronology and volumes determined by analysis of digital elevation models. This long-term eruptive flux estimate is similar to those of stratovolcanoes in continental arcs, indicating that eruptive productivity in post-collisional settings can match that of active continental margins. All Mt. Hasan eruptions, including the Holocene event, sampled zircon which crystallized coeval with earlier eruptive phases, indicating longevity of the magma plumbing system. Along with ongoing fumarole activity and evidence for mid-crustal low seismic velocity zones, this suggests that a subvolcanic magma reservoir remains active to the present day. Unlabelled Image • New population-based disequilibrium corrections improved (U–Th)/He age accuracy. • Late Pleistocene recurrence of at least one eruptive phase every 5–15 ka at Mt. Hasan. • Eruptive fluxes presented as differential volumes vs. ages to accent recent trends. • Long- and short-term fluxes of post-collisional volcanism similar to arc settings. • Protracted zircon crystallization supports Mt. Hasan as an active volcanic center. [ABSTRACT FROM AUTHOR]

Seismic waves are commonly used to investigate how the soils behave during the earthquake. The goal of this study is to predict the porosity of shallow clay soils from seismic wave velocities investigated the dynamic properties of the soil and to develop the porosity graphs depending on geotechnical properties of the soils. The parameters used to determine porosity are compressional (P) and shear (S) wave velocities, seismic velocity ratio, Poisson ratio, bulk modulus, shear modulus. This study calculates bulk modulus, shear modulus and Poisson ratio from P- and S-wave velocities obtained by using the seismic-refraction method, and porosity values using grain and dry densities of core samples obtained from several boreholes within the study area. The study area is located in western Turkey, and has predominantly clay-silt-sand-gravel deposits. The data of the clay soils within the area were separately arranged based on the values of the Poisson ratio, seismic P wave velocity, seismic velocity ratio (Vp/Vs) and the stiffness of the clay soils. Using these parameters, new multi-parameter relationships were established among shear modulus, Poisson ratio, seismic velocities and porosity of clay soils. The errors of the parameters used for each relationship were determined using the error norm technique. According to the results of the error norm technique, the shear wave velocity and shear module have lowest error for estimating porosity. Consequently, the proposed relationships are recommended to estimate porosity of shallow clay soils. These relationships, in addition to estimate the porosity of clay soil, can be interpreted whether the liquid and/or gas saturation of pores of this soil. Also, the experimental results show that if the ratio of Vp/Vs < 1.53, the pores spaces of the clay soil are filled with gas. • P- and S-wave velocities were obtained from the seismic-refraction method. • Elastic parameters and Poisson ratio were calculated from seismic velocities. • Porosity values were obtained from grain and dry unit weights of core samples • Relationships were newly established among shear modulus, Poisson ratio, seismic velocities and porosity of clay soils • The errors of dynamic parameters to estimate the porosity of clay soils were determined depending on error norm technique. [ABSTRACT FROM AUTHOR]

The existence of the inclined bedrock at the basin edges bring about the concentration of the damages at these areas. The graben-like Duzce Basin with a low inclined subsurface topography is prone to exhibit such effects. In this study, at the first, Duzce Basin edge model is extracted from the data obtained from performed microtremor surveys as well as geotechnical investigations. Using these data, the basin stratification and shear wave velocity profile as well as the geotechnical properties of the layers is identified. Based on these data, the idealized Duzce Basin edge model is proposed. Then, to estimate the dynamic behavior of the Duzce Basin, a fully nonlinear method based on explicit finite difference scheme is performed. The basin is subjected to the collection of 16 strong ground motions with different peak ground accelerations (PGA) levels. Using the recorded acceleration at 12 surface points along the basin edge the variation of the maximum spectral amplification factor is reported. The results show that the Duzce Basin edge behavior is greatly affected by inclined bedrock. Also, the sensitivity of the different points of the basin to different periods is investigated. It is seen that in the case of the motions with the PGA of 0.2 g, this band spans between 0.1s to about 1.7s. • Idealized 2D model of the Duzce basin using underground and geological investigations. • The amplification behavior of the basin edge with inclined bedrock. • The effect of motion intensity on amplification of Duzce basin edge. • The sensitivity of the basin edge to lower period and inner parts to higher ones. [ABSTRACT FROM AUTHOR]