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Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ege Journal of Fisheries & Aquatic Sciences (EgeJFAS) / Su Ürünleri Dergisi is the property of Ege Journal of Fisheries & Aquatic Sciences (EgeJFAS) / Su Urunleri Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective:Aedes cretinus, a white and black stripped Aedes species, shares morphological similarities with Aedes albopictus and Aedes aegypti which are among the most important vectors and invasive species in the world. Due to its limited distribution and low population density, information on the biology and ecology of the species has been limited so far. This study aimed to determine distribution of Ae. cretinus in Türkiye.Methods:Field works have been carried out in the Mediterranean, Aegean and Marmara Regions of Türkiye. Larval samples were collected by larval dippers while adult mosquito catches were performed using the human landing catch method and CDC-light traps.Results:A total of 44 different Ae. cretinus populations were identified in the Mediterranean, Aegean and Marmara Regions of Türkiye. The larval specimen collected from small containers, tires, tree holes and natural small habitats. A plane (Platanus orientalis), walnut (Juglans regia), Türkiye oak (Quercus cerris), chestnut (Castenea sativa) and cedar (Cedrus libani) tree holes are the main larval habitats in which the specimen collected. In some localities, larvae were found together with Anopheles plumbeus, Anopheles claviger and Aedes geniculatus larvae in tree holes. Human landing catch method captured a greater number of females than CDC-light traps.Conclusion:This study determined the distribution of Ae. cretinus in Türkiye for the first time. Information on respective geographic distribution of Ae. cretinus is fundamental for effective control programmes. Further studies are needed to understand the biology and ecology of these species.

This overview presents the different water masses present in the various primary and secondary marine regions of the Mediterranean Sea and Black Sea, providing information on their main physical characteristics (i.e., temperature, salinity, density), the water depths at which they have been observed and the processes involved in their formation. There is a characteristic difference in the overall hydrology of the Mediterranean Sea compared to the Black Sea, in terms of the number and characteristics of water masses and their formation processes, although they form a single (integrated) marine system. This difference is explained by the limited communication between the two seas through the Sea of Marmara and its straits (the Dardanelles and Bosporus) and by the fact that the Mediterranean Sea is a condensation basin while the Black Sea is a dilution basin; therefore, the deficit of water in the former is compensated by the inflow of Atlantic waters, while the surplus in the latter outflows to the Aegean Sea. In total, 21 different water masses have been identified in the Mediterranean Sea (excluding the Straits of Gibraltar and the Sea of Marmara) compared to the 5 water masses identified in the Black Sea (excluding the Sea of Azov). This large number of water masses is attributed to coastal morphology (i.e., presence of straits) and submarine relief (i.e., deep basin separated by shallow sills) and different formation processes. [ABSTRACT FROM AUTHOR]

The Ganos fault that ruptured on 9 August 1912 (Mw: 7.4) is the westernmost inland segment of the North Anatolian fault (NAF). Here, the Ganos fault is bounded at its two tips with offshore faults segments, in the Sea of Marmara to the east and the Gulf of Saros to the west in the North Aegean Trough. Therefore, the paleoseismology of the 45-km-long inland fault is of importance to the seismic hazard analysis related to offshore active faults and in particular for the seismic gap in the Marmara Region. Earlier studies have established an earthquake chronology for the western and eastern inland tips of the Ganos fault. Here, we extend the paleoseismic studies toward the central segment. Three trenches at Yörgüç have revealed evidence for two faulting events, possibly post-1669 CE ±30 years, which can be correlated to the 1659 or 1766, and the 1912 historical earthquakes. At Yeniköy, we determined an offset of 46 ± 1 m and 47 ± 1 m on a stream channel and a ridge-crest, respectively. In two trenches we determined two faulting events for the last 1000 years and seven events for the last 3500 years. In trench T5, the base of the displaced stream channel provides a calibrated date of 829-591 BCE. Using the 46 ± 1 m right-lateral displacement, we calculate a slip rate of 16.9 ± 0.7 mm/year for the last 2732 ± 119 years. A combined analysis with earlier paleoseismic studies on the Ganos fault suggests that the historical earthquakes of 1912, 1766b or 1659, 1354 or 1343a, and 1063 ruptured the entire inland fault section. In such a case, the recurrence interval for this section of the NAF corresponds to 283 ± 81 years. Combining earlier estimations, we suggest an average slip rate of 17.1 ± 0.9 mm/year for the last 2700 years and observe a characteristic slip behavior of 4.5 to 5 m per event for this section of the North Anatolian plate boundary fault. [ABSTRACT FROM AUTHOR]

The coccolithophorid Ochrosphaera neapolitana was reported for the first time from samples obtained during a large-scale mucilage event in the Sea of Marmara in May 2022 in a previous study. We also found this species in our samples obtained about a year ago (i.e., in June 2021). In our study, O. neapolitana was further isolated and produced in the laboratory as a monoculture for further investigations using electron microscopy and molecular methods. Ochrosphaera neapolitana was identified using a small sub-unit (SSU) rRNA sequence and subsequent phylogenetic analysis. During the laboratory experiments, O. neapolitana was surprisingly observed to produce conspicuous levels of mucilage as a skim layer in mono- or multi-species cultures, mainly comprising other diatom species. This observation could be a significant milestone in understanding the reasons and mechanisms of mucilage events that occur in the Sea of Marmara. [ABSTRACT FROM AUTHOR]

Copyright of TÜBA-AR: Turkish Academy of Sciences, Journal of Archaeology is the property of Turkish Academy of Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purse seiners generally try to maximize their revenues by targeting multiple species, starting with the most valuable ones available. The technology and capacity of purse seiners can be exceptionally high for the stocks found in the Marmara Sea, Turkey's only inland sea, due to its small size and nearly totally enclosed nature. Due to their large capabilities, they are responsible for the majority of catches and hence declines from this sea and thus should be held responsible for the poor state of marine stocks in the region. This study examines the catch compositions, expenses, and revenue sharing of purse seiners by using one representative vessel class for each of the four vessel length categories in the Marmara Sea. Surveys were also conducted with purse seine fishers to assess their perceptions related to fisheries management strategies along with their ideas for transitioning towards sustainable fisheries. As purse seiners are prominent stakeholders in the Marmara Sea fisheries, they should be incorporated into management guidance for effectiveness, along with other stakeholders. This study provides novel socio-economic data along with their perspectives, which may assist in improving policy decisions and capabilities. Our results demonstrate that purse seiners do not consider that their actions are a contributing factor to the current state of the fisheries, they trust in their amassed historical local knowledge, and seem to want to rebuild the resources, however only with minimal rules imposed on their sector. [ABSTRACT FROM AUTHOR]

This overview presents the different water masses present in the various primary and secondary marine regions of the Mediterranean Sea and Black Sea, providing information on their main physical characteristics (i.e., temperature, salinity, density), the water depths at which they have been observed and the processes involved in their formation. There is a characteristic difference in the overall hydrology of the Mediterranean Sea compared to the Black Sea, in terms of the number and characteristics of water masses and their formation processes, although they form a single (integrated) marine system. This difference is explained by the limited communication between the two seas through the Sea of Marmara and its straits (the Dardanelles and Bosporus) and by the fact that the Mediterranean Sea is a condensation basin while the Black Sea is a dilution basin; therefore, the deficit of water in the former is compensated by the inflow of Atlantic waters, while the surplus in the latter outflows to the Aegean Sea. In total, 21 different water masses have been identified in the Mediterranean Sea (excluding the Straits of Gibraltar and the Sea of Marmara) compared to the 5 water masses identified in the Black Sea (excluding the Sea of Azov). This large number of water masses is attributed to coastal morphology (i.e., presence of straits) and submarine relief (i.e., deep basin separated by shallow sills) and different formation processes.

An MW 4.5 earthquake took place on September 24, 2019 in the Marmara Sea. Two days after, on September 26, 2019, Marmara region was rattled by an MW5.7 earthquake. With the intention of compiling an ample strong ground motion data set of recordings, we have utilized the stations of Istanbul Earthquake Rapid Response and Early Warning System operated by the Department of Earthquake Engineering of Boğaziçi University and of the National Strong Motion Network operated by AFAD. Altogether 438 individual records are used to calculate the source parameters of events; namely, corner frequency, radius, rupture area, average source dislocation, source duration and stress drop. Some of these parameters are compared with empirical relationships and discussed extensively. Duration characteristics are analysed in two steps; first, by making use of the time difference between P-wave and S-wave onsets and then, by considering S-wave durations and significant durations. It is observed that they yield similar trends with global models. PGA, PGV and SA values are compared with three commonly used ground motion prediction models. At distances closer than about 60 km, observed intensity measures mostly conform with the GMPE predictions. Beyond 60 km, their attenuation is clearly faster than those of GMPEs. A frequency-dependent Q model is developed by using both events. Its consistency with existing regional models is confirmed. [ABSTRACT FROM AUTHOR]

The study area, Derince town, is one of the most densely industrialized (oil refineries, ports, etc.) and, therefore, populated urban areas located on the North Anatolian Fault Zone in Turkey. The study area is one of the areas that was most affected by the August 17, 1999 Kocaeli Earthquake (Mw = 7.4). A total of 10,984 buildings were heavily damaged, 6131 buildings were moderately damaged, 6803 buildings were slightly damaged and 5239 people were killed during the earthquake. The study area is located on thick sediments and therefore new settlements and industrial facilities have high earthquake hazard. The consequences of any possible earthquake will be very significant for the study area. Therefore, it is important to determine soil properties in earthquake hazard mitigation studies. The seismic vulnerability index (Kg), which depends on resonant frequency, amplification and Vs30 velocity, is a simple but powerful parameter that reflects local soil conditions which affect damage caused by an earthquake. The Kg value shows weak areas of the ground and therefore Kg can be considered to be a vulnerability index for the soil. To obtain Kg characteristics of the study area, the microtremor horizontal-to-vertical spectral ratio (HVSR) method was applied to single site measurements at 43 stations over an area of 40 km2. Calculated seismic vulnerability indices were compared with structural damage occurring during the August 17, 1999 Kocaeli Earthquake (Mw = 7.4). The results indicate that the Kg values are in good agreement with damage distribution. Large Kg values indicate weak points in the study area and most of the damage occurred in areas with large Kg values. The areas with Kg values greater than 10 seem to be the most vulnerable locations in the study. Ground conditions should be taken into account during the planning and design of urban areas. The results obtained by considering ground conditions can be used as a quick method to identify risky areas for urban planning. [ABSTRACT FROM AUTHOR]

The 150‐km seismic gap in the Sea of Marmara is the longest section of the North Anatolian Fault that has not ruptured in the last century. Recent geodetic studies suggest that the interseismic coupling along the Main Marmara Fault (MMF) is heterogeneous with locked and creeping segments. Alternatively, the MMF is fully locked, but the strain is localized asymmetrically around the fault due to the deep basins. In this study, we build 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. We conclude that the basins along the fault localize the interseismic strain, leading to slightly deeper‐estimated locking depths. The on‐land data are too far to constrain the full interseismic coupling, especially in the Central Marmara. The Western Marmara is better resolved, where we infer a ∼50‐km creeping zone. The transition from the creeping to the locked behavior in Western Marmara is around the Ganos Bend. The creeping zone correlates well with a higher rate of diffuse seismicity and repeating earthquakes, implying that the seismicity could be an indicator of interseismic behavior. Variations of earthquake focal mechanisms and associated regional stresses are also consistent with compressional and dilatational quadrants due to the creeping segment. The significant thrust components observed in the 2019 Silivri earthquake sequence north of the MMF can also be explained by the compressional loading due to the interseismic creep further west. Plain Language Summary: The Sea of Marmara, on the western extension of the North Anatolian Fault, is the only part of the fault that has not ruptured in the last century. Recent studies suggest that the interseismic locking or coupling, which is the ratio of interseismic slip rate deficit to the long‐term plate velocity, changes along the fault. Another suggestion is that the Main Marmara Fault is fully locked, and the deep basins cause strain localization and asymmetrical strain accumulation around the fault. In this study, we build a 3‐D model of the region to understand the fault locking and the basin effects on the deformation by using geodetic data. When the basin effects are considered, the estimated best‐fitting locking depths increase slightly. Especially in the Central and Kumburgaz Basin segments, the on‐land data are too far to constrain the full interseismic coupling behavior. Western Marmara is better resolved, where a transition from the 50‐km‐long creeping segment to the locked segment is well‐constrained to be located at the Ganos Bend. This unlocked segment correlates well with a high rate of earthquake activity and repeating earthquakes. We suggest that the heterogeneous interseismic coupling pattern is consistent with off‐fault focal mechanisms. Key Points: We consider the competing effects of the heterogeneous structure and interseismic behavior along the Main Marmara FaultThe basins that surround the fault lead to a more localized strain and slightly deeper locking depth estimatesThe existing data show creep in Western Marmara, which correlates well with the focal mechanisms, distribution of seismicity and repeaters [ABSTRACT FROM AUTHOR]

Global climate change will probably cause intensification of the hydrologic cycle, which can lead to alterations in extreme precipitation properties. In this study, we investigated the trend of 5-, 10-, 15-, and 30-min annual maximum rainfall series at 12 stations in the Marmara Region, Turkey, using quantile regression. The data ranges were from 46 to 71 years long. Five quantiles were used to examine the extreme rainfall series, and their quantile regression parameters were calculated. The results show that quantile regression is a powerful tool to compute trends with a more inferential context, which was validated with the notable differences between the trends at chosen quantiles and the classical ordinary least squares method. Concerning the problem of the analysis of climate trends, the quantile regression method seems to provide a perspective from a more detailed understanding of processes in the climate system in terms of characteristics of climate variability and extremity. [ABSTRACT FROM AUTHOR]

The coccolithophorid Ochrosphaera neapolitana was reported for the first time from samples obtained during a large-scale mucilage event in the Sea of Marmara in May 2022 in a previous study. We also found this species in our samples obtained about a year ago (i.e., in June 2021). In our study, O. neapolitana was further isolated and produced in the laboratory as a monoculture for further investigations using electron microscopy and molecular methods. Ochrosphaera neapolitana was identified using a small sub-unit (SSU) rRNA sequence and subsequent phylogenetic analysis. During the laboratory experiments, O. neapolitana was surprisingly observed to produce conspicuous levels of mucilage as a skim layer in mono- or multi-species cultures, mainly comprising other diatom species. This observation could be a significant milestone in understanding the reasons and mechanisms of mucilage events that occur in the Sea of Marmara.

Purse seiners generally try to maximize their revenues by targeting multiple species, starting with the most valuable ones available. The technology and capacity of purse seiners can be exceptionally high for the stocks found in the Marmara Sea, Turkey’s only inland sea, due to its small size and nearly totally enclosed nature. Due to their large capabilities, they are responsible for the majority of catches and hence declines from this sea and thus should be held responsible for the poor state of marine stocks in the region. This study examines the catch compositions, expenses, and revenue sharing of purse seiners by using one representative vessel class for each of the four vessel length categories in the Marmara Sea. Surveys were also conducted with purse seine fishers to assess their perceptions related to fisheries management strategies along with their ideas for transitioning towards sustainable fisheries. As purse seiners are prominent stakeholders in the Marmara Sea fisheries, they should be incorporated into management guidance for effectiveness, along with other stakeholders. This study provides novel socio-economic data along with their perspectives, which may assist in improving policy decisions and capabilities. Our results demonstrate that purse seiners do not consider that their actions are a contributing factor to the current state of the fisheries, they trust in their amassed historical local knowledge, and seem to want to rebuild the resources, however only with minimal rules imposed on their sector.

Source characterization and slip history were estimated for two moderate-sized earthquakes which occurred on the southern branch of the North Anatolian Fault zone (NAFz): October 20, 2006 (Mw 4.7) Manyas Earthquake and October 24, 2006 (Mw 4.8) Gulf of Gemlik Earthquake. These events are the largest to have occurred in the last 20 years on the southern branch of the NAFz. Multi time-window linear waveform inversion technique (MTWIT) was applied to strong ground motion (SGM) data. Theoretical Green’s functions between subfaults and stations were calculated by a Discrete Wave Number Method (DWNM) using one-dimensional (1-D) velocity structure. The inversion technique used in this study yields a non-unique solution. Therefore, various rupture models were tested until a satisfactory match was obtained between observed and synthetic data. Results showed simple patterns in slip distributions. Max. slips are 0.18 m and 0.12 m and seismic moments are 3.43E+15 Nm and 1.73E+15 Nm for the Gemlik and Manyas Earthquakes, respectively. Results were compared with those of similar sized earthquakes around the world and a new empirical relationship was proposed between seismic moment and rupture area. It was aimed at providing useful information for resolving rupture mechanisms and triggering of the events in Southern Marmara region through the findings of the present study.

This paper presents major hull and rig types among Ottoman-flagged merchant ships from the 1830s to the 1860s and discusses the effects of nautical and climatic conditions on the physical features of merchant ships. The statistics demonstrate that brigs, especially frigate-built brigs, were the most common merchant ships. The article argues that despite the prevalence of Atlantic-origin ships in Ottoman waters, local geographical factors were the primary cause in determining the physical properties of Ottoman-built merchant ships, especially in the Marmara and Black Seas. Due to these nautical and climatic conditions, trehantiri was still the most common traditional ship in the Aegean Sea, and the production of perama was concentrated around Istanbul. However, these ships were mixed with martigo that sailed offshore the Black Sea. Dhow-like ships, which could sail both offshore and in the narrow waterways common in the Straits and Danube River, were also common.

Bu çalışmada, Marmara Temiz Hava Merkezi'ne (MTHM) ait hava kalitesi ölçüm istasyonlarından eş zamanlı olarak PM10 ve PM2.5 örneklemesi yapılan Edirne-Keşan, İstanbul-Silivri, İstanbul-Ümraniye, Kocaeli-Kandıra, Tekirdağ-Çerkezköy, Yalova-Armutlu istasyonlarında 2017 yılında ölçülen PM10 ve PM2.5 kütle konsantrasyonları incelenmiştir. Yapılan değerlendirmelerde kirletici konsantrasyonlarının mevsimsel ve günlük değişimleri izlenmiştir. Çalışmada, PM10 ve PM2.5 konsantrasyonlarının mevsimsel farklılıklarını karşılaştırmak için Mann-Whitney U testi uygulanmıştır. Mevsimsel faklılıkların en belirgin olduğu istasyonlar kentsel Tekirdağ ve Çerkezköy istasyonları ile kırsal Kandıra istasyonudur. Konsantrasyonlar, kentsel istasyonlarda kış mevsiminde artarken kırsal istasyonlarda yaz mevsiminde artmaktadır. Partikül boyutu ile kirletici kaynakları arasındaki ilişkinin anlaşılabilesi için PM2.5/PM10 oranları hesaplanmış ve bu oranlar incelenen istasyonların özelliklerine göre değerlendirilmiştir. Yapılan değerlendirmeler, kış mevsiminde PM2.5, yaz mevsiminde ise PM10 boyutundaki kirleticilerin hakim olduğunu göstermektedir. İncelenen istasyonlar için hesaplanan ortalama konsantrayonlar ve PM2.5/PM10 oranları, farklı ülkelerde farklı özelliklerde şehirlerde yapılan benzer örneklemelerle karşılaştırılarak sonuçların literatür ile uyumlu olduğu belirlenmiştir. Çalışmada, PM10 ve PM2.5 konsantrasyonlarının birbirleri ile ve meteorolojik parametrelerle anlamlı ilişkiler gösterdiği spearman korelasyon katsayıları hesaplanarak belirlenmiştir.

The main aim of this study is to investigate the self-relation and self-similarity of earthquakes in and around the Marmara Sea (NW Turkey) by using these obtained source parameters. With this purpose, spectral source parameters for 77 small to moderate earthquake (3.5 ≤ ML ≤ 5.2) that occurred during 2004–2018 have been determined from P and S wave spectra according to Brune's source model by using regional broadband seismograms. The average ratio of P/S wave corner frequency is found to be 1.3 that suggesting higher corner frequency for P wave. The static stress drops range from 0.1 and 136 MPa with a median value of 9.8 MPa (98 bars). The high stress drops for these events can indicate high frictional strength and low strain-rate of the faults. Similarly, the low values of the stress drop can indicate a general weakness of the faults in the study area. There is no clear dependence between the seismic moment and the static stress drop in the analyzed events but some events which have lower seismic moment value also have lower stress drop. Obtaining results indicated the corner frequency decreases with increasing of the seismic moment. Also, a slight depth dependence of the corner frequency has been observed for the analyzed events. Shallower events have larger corner frequency value than deeper events. Also, a clear depth dependence of the stress drop values has not been observed. However, the depth dependence of the seismic moment is seen more clearly. Our results indicated that the deeper events have larger seismic moment values in the study area. In spite of scattering in small events, a linear relationship between local magnitude (ML) and moment magnitude (MW) could be obtained as MW = 1.4261(± 0.31) + 0.6399(± 0.08)ML from P waves spectra and MW = 0.0136(± 0.21) + 0.9883(± 0.05)ML from S wave spectra and calculated MW values are consistent with waveform inversion (centroid moment tensor — CMT) results. These relationships may be useful for seismic hazard studies in the study area. [ABSTRACT FROM AUTHOR]

The Marmara region in Turkey is an important geological setting, both from a tectonic and a seismic hazard/risk perspective. We present a new map of crustal thickness variation across this complex region to better understand the interplay of past and present tectonic processes that have formed present‐day structure. Maps of crustal thickness are created using Ps converted phases and receiver function (RF) analysis of earthquakes recorded at all publicly available seismic stations and stations in the national monitoring network (run by AFAD Disaster and Emergency Management Authority Turkey). RFs are converted from time to depth using a local 3‐D full‐waveform tomographic model and are combined in multiphase common conversion point stacks. Direct P to S converted arrivals and associated multiples are mapped to produce continuous maps of the Moho discontinuity. Results show Moho depths ranging from 26–41 km with a regional trend of westward thinning reflecting the effects of the extensional regime in western Anatolia and the neighboring Aegean Sea. The thinnest crust is observed beneath the western end of the Sea of Marmara, attributed to transtensional basin opening. A distinct region of increased crustal thickness bounded by the West Black Sea Fault in the west, and the northern strand of the North Anatolian Fault in the south, defines the ancient crustal terrane of the Istanbul Zone. Isostatic arguments indicate that the thickened crust and lower elevation in the Istanbul Zone require it to be underlain by thicker lithosphere, a conclusion that is consistent with its hypothesized origin near the Odessa shelf. Key Points: We present a new regional map of Moho topography in the Marmara region, based on RF CCP stacksWestward crustal thinning reflects the effect of ongoing extension in western Anatolia and the neighbouring Aegean regionAbrupt changes in crustal thickness define the non‐crustally compensated ancient terrane of the Instanbul block [ABSTRACT FROM AUTHOR]

Objective: Fishing has long been known as one of the most dangerous occupational groups. Fishermen are faced with long working hours, difficult weather conditions and a heavy workload, and this poses various health risks. However, fishermen consume high amounts of seafood which are known to be protective against various diseases, compared to the general population. In this study, it was aimed to evaluate the general health status of fishermen in the Marmara region by comparing them with the control group. Methods: This descriptive study was carried out between April 2018-August 2019 in Istanbul, Kocaeli, Tekirdağ and Yalova provinces. The study included 263 fishermen and 89 controls. In the collection of the data, a questionnaire containing questions about the sociodemographic, individual and health characteristics of the participants and the General Health Questionnaire used to determine the level of general psychopathology were used. Student-t test, Mann Whitney U test and chisquare test were used for statistical analysis. Results: Fishermen's smoking and alcohol use rates were found to be higher compared to the control group, but fishermen did not differ from the control group in terms of chronic diseases, medication use and health complaints. There is no difference between fisherman and control groups in terms of General Health Questionnaire scores. General Health Questionnaire scores of people aged 50 and under and those with any health complaints were found to be statistically significantly higher in both groups. General Health Questionnaire scores of those with chronic disease in the fisherman group and smokers in the control group were higher. Conclusion: Fishermen working under stressful conditions in a dangerous profession should be closely monitored for their physical and mental health problems. It should not be forgotten that risky health behaviors such as smoking and alcohol consumption are frequently observed in this group and individuals should be directed to professional support programs to prevent this situation. [ABSTRACT FROM AUTHOR]

It is well known that the mechanical and physical properties of subsoil layers as well as poor construction practices play an important role in determining the level of structural damage sustained from earthquakes. Thus, sufficient knowledge of these properties is essential for estimating the weak points of a region. The ground vulnerability index (Kg), an indicator of the weak points of a region, also has a substantial importance role in mitigating earthquake hazards in multidisciplinary studies. In this context, we have used engineering basement shear wave velocity (vs30), fundamental frequencies and peak amplitude values of the horizontal-to-vertical ratio (H/V) to calculate Kg values for the study area (Kocaeli Province, Turkey). Structural damage was investigated after the August 17, 1999 Kocaeli (Mw = 7.4) Earthquake and compared with the calculated Kg values. The results indicate that the Kg values decrease towards the southern part of the study area, which is in good agreement with damage distribution from this earthquake. Kg values of >10 appear to be indicative of the most vulnerable areas in the study area. Structures built along the coastlines in Değirmendere area were the mostly severely damaged or collapsed entirely; we found that the subsoil beneath them have high Kg values of between 10 and 25 In contrast, Kg values in the southern districts, which sustained little or no damage, are relatively low (Kg < 10). In our study, the Kg values and soil types showed good agreement. Potential vulnerable areas also have poor subsoil conditions. Therefore, it could be important to consider these results for the future planning and designing of urban areas. These results could also be used as a rapid way to detect potential vulnerable areas before the occurrence of a destructive earthquake. [ABSTRACT FROM AUTHOR]

Scolytinae subfamily (Coleoptera: Curculionidae) is represented by 135 species in Turkey including 8 species of the genus Hylastes Ericson and 7 species of the genus Crypturgus Ericson. A total of 79 adult individuals of Hylastes opacus Erichson and 6 adult individuals of Crypturgus hispidulus Thomson, C. G. were obtained from log and pheromone traps in pine stands at twelve localities during 2014. H. opacus and C. hispidulus were recorded for the first time in Turkey. H. opacus were obtained from trap logs of Pinus brutia and Pinus nigra and also pheromone traps in P. brutia stands. Adult individuals of C. hispidulus were observed in association with Orthotomicus erosus and Pityogenes pennidens on P. brutia and P. nigra log traps. [ABSTRACT FROM AUTHOR]

This article explores how the Royal Navy, in light of its highly ambiguous relationship with the submarine, was able to negotiate the image of their own submarines and submariners into their existing concepts of 'the best traditions and customs of the service'. It will consider how British submariners viewed themselves, how the surface fleet felt towards this new breed of naval men, and how their actions were constructed in a public sphere. This article will consider the various constructions of the heroic narratives surrounding campaign and will explore how and why these various narratives were constructed and reconstructed as they were, and what impact 'heroism' had on the prosecution of the campaign itself. [ABSTRACT FROM AUTHOR]

Among the coastal districts of mega city Istanbul, Bakirkoy is one of the most critical one with the importance of air and marine transportation and presence of many other coastal facilities and structures that are prone to suffer from marine hazards. In the history, the Sea of Marmara has experienced numerous earthquake and landslide events and associated tsunamis. Therefore, tsunami risk assessment is essential for all coastal districts of Istanbul, including Bakirkoy district. In this study, a further developed methodology for tsunami human vulnerability and risk assessment Metropolitan Tsunami Human Vulnerability Assessment (MeTHuVA) is applied for Bakirkoy district of Istanbul, considering earthquake generated tsunamis. High-resolution tsunami hazard analysis is performed with the integration of coastal inundation computation with tsunami numerical tool NAMI DANCE and tsunami human vulnerability assessment with GIS-based multi-criteria decision analysis methods (MCDA). Using analytical hierarchy process method of MCDA, a hierarchical structure is established, composed of two main elements of tsunami human vulnerability: Vulnerability at Location and Evacuation Resilience. Tsunami risk assessment for Bakirkoy district is calculated by integrating result of hazard and vulnerability assessments with a risk relation that includes a parameter ( n), which represents the preparedness and awareness level of the community. Tsunami simulations revealed that the maximum inundation distance is over 350 m on land and water penetrates almost 1700 m along Ayamama stream. Inundation is observed in eleven neighborhoods of Bakirkoy district. In the inundation zone, maximum flow depth is found to be over 5.7 m. The inundated area forms 4.2% of whole Bakirkoy district, and 62 buildings are located in the inundation zone. Hazard, vulnerability and risk assessment results for different neighborhoods of Bakirkoy district are presented and discussed. [ABSTRACT FROM AUTHOR]

The diatoms are one of the most important groups of organisms for biomonitoring studies. In Turkey, most previous applications of diatoms to water quality monitoring have focused on the pennate diatoms, with almost no attention given to the centric forms. The paper presents the centric diatoms in some river catchments in Central Anatolia (Konya closed catchment and Kızılırmak) and Western Anatolia (Marmara, Sakarya, Susurluk, Akarçay, Küçük Menderes, and Meriç-Ergene in the Marmara and Aegean regions). The survey of these catchments is based on samples collected between 2009 and 2013 from 33 different locations, including some springs from Türkmen Mountain and Domaniç forest, as well as small streams and big rivers of the Anatolian Peninsula. Altogether 30 taxa were found, of which 14 are new records for the freshwater diatom flora of Turkey. [ABSTRACT FROM AUTHOR]

Güney Marmara Bölgesi’nin (Susurluk drenaj havzası-SDH) suları ve tortulları büyük ölçüde önce Manyas ve Ulubat göllerinde toplanır, sonra tek kanaldan Marmara Denizi’ne ulaşır.Mevcut akaçlama sistemi ile buradaki gözlem istasyonları SDH’ndaki aşınma hızını ve dolayısıyla buradaki büyük ölçekli vadilerin kazınma sürelerini araştırma olanağı vermektedir. Bu yönde veri elde etmek için, Ulubat Gölü’nün eski tortulları ve bunların kimyasal kapsamları sondajlar yardımıyla çalışılmıştır. Karotlarla kesilen göl tortulları içindeki bor iyonu alttan üste doğru 4 m seviyesinde aniden artmakta olup bu değişme Emet Vadisi’ndeki borat yataklarının aşınmaya başlamasıyla ortaya çıkmıştır. Aşınma-depolanma ilişkileri dikkate alınarak Emet Vadisi’ndeki deşilme hızı 1,4 cm/yıl, bu değerin tüm araziye uygulanmasıyla vadinin toplam kazılma süresi 75 bin yıl olarak hesaplanmaktadır. Jeolojik süreçlerin tekdüze olmadığı dikkate alınarak, bu yaşın mutlak olmayacağı, ancak mevcut taşınma ve depolanma hızlarına göre vadilerin kazılma süresinin 300 bin yıldan daha da geriye gitmeyeceği söylenebilir. Öyle anlaşılıyor ki, hızlı aşınmanın önemli nedenlerinden birisi Marmara Denizi’nin son Buzul Çağında göl halinde oluşudur. Alçak taban düzeyi, kaynak alan ile birikim yeri arasında belirgin yükseklik farkı yaratmış ve erozyonun hızlanmasına yol açmıştır..

The North Anatolian Fault (NAF) is a 1200 km long dextral strike-slip fault which is part of an east-west trending dextral shear zone (NAF system) between the Anatolian and Eurasian plates. The North Anatolian shear zone widens to the west, complicating potential earthquake rupture paths and highlighting the importance of understanding the geometry of active fault systems. In the central portion of the NAF system, just west of the town of Bolu, the NAF bifurcates into the northern and southern strands, which converge, then diverge to border the Marmara Sea. At their convergence east of the Marmara Sea, these two faults are linked through the Mudurnu Valley. The westward continuation of these two fault traces is marked by further complexities in potential active fault geometry, particularly in the Marmara Sea for the northern strand, and towards the Biga Peninsula for the southern strand. Potential active fault geometries for both strands of the NAF are evaluated by comparing stress models of various fault geometries in these regions to a record of focal mechanisms and inferred paleostress from a lineament analysis. For the Marmara region, the best-fit active fault geometry consists of the northern and southern bounding faults of the Marmara basin, as the model representing this geometry better replicated primary stress orientations seen in focal mechanism data and stress field interpretations. In the Biga Peninsula region, the active geometry of the southern strand has the southern fault merging with the northern fault through a linking fault in a narrow topographic valley. This geometry was selected over the other two as it best replicated the maximum horizontal stresses determined from focal mechanism data and a lineament analysis. [ABSTRACT FROM AUTHOR]

Objective: Aedes cretinus , a white and black stripped Aedes species , shares morphological similarities with Aedes albopictus and Aedes aegypti which are among the most important vectors and invasive species in the world. Due to its limited distribution and low population density, information on the biology and ecology of the species has been limited so far. This study aimed to determine distribution of Ae. cretinus in Türkiye., Methods: Field works have been carried out in the Mediterranean, Aegean and Marmara Regions of Türkiye. Larval samples were collected by larval dippers while adult mosquito catches were performed using the human landing catch method and CDC-light traps., Results: A total of 44 different Ae. cretinus populations were identified in the Mediterranean, Aegean and Marmara Regions of Türkiye. The larval specimen collected from small containers, tires, tree holes and natural small habitats. A plane ( Platanus orientalis ), walnut ( Juglans regia ), Türkiye oak ( Quercus cerris ), chestnut ( Castenea sativa ) and cedar ( Cedrus libani ) tree holes are the main larval habitats in which the specimen collected. In some localities, larvae were found together with Anopheles plumbeus , Anopheles claviger and Aedes geniculatus larvae in tree holes. Human landing catch method captured a greater number of females than CDC-light traps., Conclusion: This study determined the distribution of Ae. cretinus in Türkiye for the first time. Information on respective geographic distribution of Ae. cretinus is fundamental for effective control programmes. Further studies are needed to understand the biology and ecology of these species.

In this study, we analyze the ground motion characteristics of October 20, 2006 Manyas (ML=5.2) and October 24, 2006 Gemlik (ML=5.2) earthquakes. Both earthquakes occurred on the southern branch of the North Anatolian Fault Zone in Marmara region, which has a lower seismic hazard relative to the northern branch. The two events are the largest earthquakes on the southern branch recorded by a modern and vast seismological network; therefore their records are valuable to evaluate seismic risk of the region and the understanding of physics of wave propagation. The analysis show that the attenuation of PGAs is very similar for two earthquakes, but they are not represented by the empirical relation obtained for earthquakes occurred on the northern branch. The waveforms of the Gemlik earthquake recorded by BYTNet array indicate an EW rupture orientation with right-lateral slip which fits to the general character of the southern branch. Ground motions at the stations located within basin are strongly influenced by the presence of locally induced surface waves resulting in lengthening of significant shaking duration with respect to a nearby ridge site. Surface wave characteristics are very similar for the Manyas and Gemlik earthquakes, but variations are observed on components which may be related to 3D basin geometry. Resonance frequencies of the surface waves generated within basin are very close to the 1D site resonances at the stations obtained from H/V ratios of S waves. The resonance frequency is about 0.2 Hz within the large Bursa Plain, whereas it increases to about 0.9 Hz within the smaller Gemlik Plain.

In this study, near-surface geophysical techniques are used to investigate the physical characteristics of the Buyukcekmece landslide (Istanbul, Turkey). The Buyukcekmece landslide has continuous activity at a low velocity and is classified as a complex mechanism. It includes rototranslational parts, several secondary scarps, several landslide terraces, and evidence of two earth flows. It mainly develops in the clayey layers of the Danismen Formation. According to our findings, P-wave velocities ranging from 300 m/s to 2400 m/s do not provide notable discrimination between sliding mass and stable soil. They show variations in blocks reflecting a complex structure. We obtained the S-wave velocity structure of the landslide up to 80 m by combining the analysis of MASW and ReMi. It is clear that S-wave velocities are lower in the landslide compared to those of the stable area. Identical S-wave velocities for the entire area at depths higher than 60 m may point out the maximum thickness of the landslide mass. Resonance frequencies obtained from the H/V analysis of the landslide area are generally higher than those of the stable area. The depths computed by using an empirical relationship between the resonance frequency and the soil thickness point out the failure surfaces from 10 to 50 m moving downslope from the landslide crown area. The resistivity values within the landslide are generally lower than 30 Ω m, i.e., a typical value for remolded clayey debris. The geophysical results reflect an overview of the geological model, but the complexity of the landslide makes it difficult to map the landslide structure in detail. [ABSTRACT FROM AUTHOR]

In this study, marine Pleistocene mollusc faunas from deposits along the southern shores of the Izmit Bay area (Marmara Sea, Turkey) are reviewed. Ten samples from five localities spanning middle and late Pleistocene intervals are assessed and compared to four samples of a Holocene age. For the Pleistocene fauna, a total of 59 mollusc species (33 bivalve and 26 gastropod species) are recorded, some of which are reported for the first time for this region. The middle Pleistocene fauna bears large resemblance to the late Pleistocene faunas, even though marine conditions were lacking during sea-level drops in the Marmara Sea Basin in intervening times. The middle Pleistocene mollusc fauna is dominated by species that typify the so-called Uzunlarian faunas while the late Pleistocene mollusc fauna is indistinguishable from Karangatian faunas of the Black Sea Basin. Several common species (including Bittium reticulatum , Rissoa spp. and Lucinella divaricata ) show that the both Uzunlarian and Karangatian assemblages of Yalova fauna mainly represent seagrass palaeoenvironments. Palaeosalinities estimates for the Yalova area are uppermost mesohaline to polyhaline, typically around or above 20 psu, which is almost similar to the optimum salinity estimates for the middle Pleistocene Uzunlarian. However, it is slightly lower then the Upper Pleistocene Karangatian, representing the location of the Yalova area in an embayment with freshwater input at that time. The Yalova sections are located in the southern flank of the North Anatolian fault system responsible for a strong local uplift of the study area. The sections contain evidence for three marine high stands, separated by terrestrial intervals. When regional uplift rates (approximately 0.2 mm/y) and oceanic sea-levels are considered it is likely that the three highstand intervals correspond to relative sea level high stands of MIS7, MIS5e and possibly MIS5d but further study is required to confirm such a suggestion. [ABSTRACT FROM AUTHOR]

We invert the present day states of stresses for five apparent earthquake clusters in the Northern branch of the North Anatolian Fault in the Sea of Marmara. As the center of the Sea of Marmara is prone to a devastating earthquake within a seismic gap between these selected clusters, sensitive analyses of the understanding of the stress and strain characteristics of the region are all-important. We use high quality P and S phases, and P-wave first motion polarities from 398 earthquakes with ML ≥ 1.5 using at least 10 P-wave first motion polarities (FMPs), and a maximum of 1 inconsistent station, obtained from a total of 105 seismic stations, including 5 continuous OBSs. We report here on large numbers of simultaneously determined individual fault plane solutions (FPSs), and orientations of principal stress axes, which previously have not been determined with any confidence from the basins of the Sea of Marmara and prominent fault branches. We find NE–SW trending transtensional stress structures, predominantly in the earthquake clusters of the Eastern Tekirdağ Basin, Eastern Çınarcık Basin, Yalova and Gemlik areas. We infer that a dextral strike-slip deformation exist in the Eastern Ganos Offshore cluster. Furthermore, we analyze FPSs of four ML ≥ 4.0 earthquakes, occurred in seismically quiet regions after 1999 Izmit earthquake. Stress tensor solutions from a cluster of small events that we have obtained, correlate with FPSs of these moderate size events as a demonstration of the effectiveness of the small earthquakes in the derivation of states of local stresses. Consequently, our analyses of seismicity and large numbers of FPSs using the densest seismic network of Turkey contribute to better understanding of the present states of the stresses and seismotectonics of the Sea of Marmara. [ABSTRACT FROM AUTHOR]

Earthquake is a natural hazard associated with geologic events. In Turkey, which is on the Alp’s Mountain belt, people have lost lives and property because of this disaster. Although seismotectonic regions of Turkey are shown in general on Turkish earthquake map, which is made by General Directorate of Disaster Affairs, studies on local areas are needed. Main objective of this study was to put forward neotectonic characteristics and seismicity of the Balıkesir Plain and its surroundings. Firstly, neotectonic features of the region were studied. Secondly, for this paper, earthquake records between 1900 and 2000 years were examined by suitable statistical methods. Earthquakes’ magnitudes and depths were then classified. In first part of the study, earthquakes’ epicenters more than 4.0 Mw on the Southern Marmara-Northwest Aegean regions between 38o50′N-40o50′N latitudes and 26o00′E-29o40′E longitudes and, in the second part, earthquakes’ epicenters on the Balıkesir Plain and its surroundings between 39o77′N-40o50′N latitudes and 27o76′E-28o15′E longitudes were shown and analyzed on the maps. In the study area, probability of earthquake occurrences andrepetitions were calculated from the statistical aspects by using Poisson model. The study concluded with the analyses of values and provided some suggestions.

ABSTRACT In this study, circulation types, their long-term mean occurrence frequencies and relationships with precipitation are investigated for the region Marmara, which is the most populated, agriculturally developed and industrialized area in Turkey. Automated Lamb Weather Types classification method is applied on NCEP/NCAR daily mean sea level pressure data to determine the circulation types. Northeasterly (NE) and easterly (E) types are found to be the most frequent both on the annual basis and during winter (DJF, the wettest season in the region). Circulation types with the highest rainfall potential, namely the cyclonic (C) and the northerly (N), are among the least frequent; therefore they are not the dominant 'rainfall modes'. Instead, NE and E have the greatest contribution to the regionally averaged rainfall amount, although they do not have the highest potential to create precipitation. This shows that Marmara Region receives a substantial amount of precipitation from northerly and easterly maritime trajectories, implying a profound influence of the Black Sea on the rainfall regime in this area. However, rainfall at the stations that are far away or less affected by the Black Sea (especially at the ones in the west) occurs during types with a southerly component (S, SW and SE). Our results reveal that, in Marmara Region, the response of precipitation to atmospheric circulation is rather complex and spatially inhomogeneous; in line with the complex topography of the area. Therefore, water management policies should be adopted accordingly, taking all local characteristics into account. [ABSTRACT FROM AUTHOR]

Ecosystems in the tropics are predicted to have stronger responses to nutrient enrichment, greater diversity, and more intense biotic interactions than in temperate areas. Mangrove forests, which occur across a broad biogeographic range from warm temperate to tropical, provide a unique opportunity to test these hypotheses by investigating the responses of herbivores to nutrient enrichment in temperate versus tropical latitudes. Mangroves are complex intertidal ecosystems with spatial differences in structure and diversity along tidal gradients and are threatened globally by human activities including nutrient over-enrichment. In this study, we used long-term fertilization experiments at the Indian River Lagoon, FL; Twin Cays, Belize; and Bocas del Toro, Panamá to determine how increased nutrients impact herbivore abundance and herbivory of Rhizophora mangle at the tree, forest, and regional scales. At these locations, which span approximately 2185 km and 18.4º of latitude, we fertilized individual trees with one of three treatments (Control, +N, +P) in two zones (fringe, scrub) along transects perpendicular to the shoreline and measured their responses for 4 years. Herbivory was measured as folivory, loss of yield, and tissue mining. Although nutrient enrichment altered plant growth, leaf traits, and nutrient dynamics, these variables had little effect on folivory at any location. Our results did not support the prediction that herbivory and per capita consumption are greatest at the most tropical location. Instead, folivory was highest at the most temperate location and lowest at the intermediate location. Folivory was generally higher in the fringe than in the scrub zone, but the pattern varied by location, herbivore, and nutrient treatment. Folivory by a dominant herbivore, Aratus pisonii, decreased from the highest to the lowest latitude. Our data suggest that factors controlling population dynamics of A. pisonii cascade to the mangrove canopy, linking herbivory to crab densities. [ABSTRACT FROM AUTHOR]

Abstract: In closed marine basins and large lakes, gravity re-depositional processes often result in specific turbidites with two abruptly separated layers: a coarse graded lower term and an upper homogenous fine-grained term. An additional mixed term generally occurs in between, indicating to and from particle displacements. The later ones are related to oscillating bottom currents responsible for a high increase of the fine fraction segregation, within the reworked wasted mass. The whole sedimentary event is the association “homogenite+turbidite” (HmTu), which specific a settling condition area here characterized through Anisotropy of Magnetic Susceptibility (AMS). Homogenites's magnetic foliation appears anomalously high with respect to their expected state of compaction, and strikingly higher than hemipelagites's values. We applied this approach to Late Pleistocene/Holocene sediments from the Sea of Marmara and from the Gulf of Corinth. Grain-size and other magnetic parameters related to mineralogy are added to better assess the granular array influence on AMS. As HmTu is considered as often related to earthquake-triggering and tsunami/seiche effects, AMS appears as a useful tool for subaqueous paleoseismic investigations. First, it may evidence the signature of paleo-earthquakes; second, it permits to decipher hemipelagic intervals which are inferred to represent the time elapsed between two successive reworking events. [Copyright &y& Elsevier]

Copyright of Journal of the Cukurova University Institute of Social Sciences is the property of Cukurova University Institute of Social Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Estimating the spatial distribution of long term precipitation plays a very important role in hydrological models that help us to understand climatic events. Since it is impossible to measure the amount of rainfall and temperature at every point within a geographic area, interpolation methods are used to model the surface of these data as continuous surfaces. The Thiessen method, which is one of the most used interpolation methods, was employed to compute spatially distributed monthly precipitation from long term precipitation data obtained from 35 metrological stations scattered over the Marmara region. The Mann-Kendall non-parametric test and Sen's method were used to determine the presence of temporal trends in monthly aerial precipitation sets within the study area for a period of 32 years (1975-2006). The period was divided into two sections, 1975-2006 and 1985-2006. Trends in precipitation were identified in the 1975-2006 period but the test statistic values were not significant. For the 1985-2006 period, an increasing trend was identified for the months of August, September and February with a significance level of 0.05. [ABSTRACT FROM AUTHOR]

George G. Roussas was born in the city of Marmara in central Greece, on June 29, 1933. He received a B.A. with high honors in Mathematics from the University of Athens in 1956, and a Ph.D. in Statistics from the University of California, Berkeley, in 1964. In 1964-1966, he served as Assistant Professor of Mathematics at the California State University, San Jose, and he was a faculty member of the Department of Statistics at the University of Wisconsin, Madison, in 1966-1976, starting as an Assistant Professor in 1966, becoming a Professor in 1972. He was a Professor of Applied Mathematics and Director of the Laboratory of Applied Mathematics at the University of Patras, Greece, in 1972-1984. He was elected Dean of the School of Physical and Mathematical Sciences at the University of Patras in 1978, and Chancellor of the university in 1981. He served for about three years as Vice President-Academic Affairs of the then new University of Crete, Greece, in 1981-1985. In 1984, he was a Visiting Professor in the Intercollege Division of Statistics at the University of California, Davis, and he was appointed Professor, Associate Dean and Chair of the Graduate Group in Statistics in the same university in 1985; he served in the two administrative capacities in 1985-1999. He is an elected member of the International Statistical Institute since 1974, a Fellow of the Royal Statistical Society since 1975, a Fellow of the Institute of Mathematical Statistics since 1983, and a Fellow of the American Statistical Association since 1986. He served as a member of the Council of the Hellenic Mathematical Society, and as President of the Balkan Union of Mathematicians. He is a Distinguished Professor of Statistics at the University of California, Davis, since 2003, the Chair of the Advisory Board of the "Demokritos Society of America" (a Think Tank) since 2007, a Fellow of the American Association for the Advancement of Science since 2008, and a Corresponding Member of the Academy of Athens in the field of Mathematical Statistics, elected by the membership in the plenary session of April 17, 2008. [ABSTRACT FROM AUTHOR]

Copyright of Journal of International Social Research is the property of Journal of International Social Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We develop a data set of aftershock recordings of the 1999, M = 7.4 Izmit and M = 7.2 Duzce (Turkey) earthquakes to study their source parameters. We combined seismograms from 44 stations maintained by several sources (organizations) to obtain a unified data set of events (2.1 ≤ Mw ≤ 5.5). We calculate source parameters of these small earthquakes by two methods that use different techniques to address the difficulty in obtaining source spectra for small earthquakes subject to interference from site response. One method (program NetMoment (NM), H utchings, 2004) uses spectra of direct S waves in a simultaneous inversion of local high-frequency network data to estimate seismic moment, source corner frequency ( f c), site attenuation ( k) and whole-path Q. This approach takes advantage of the source commonality in all recordings for a particular earthquake by fitting a common Brune source spectrum to the data with a and individual k. The second approach (M ayeda et al., 2003) uses the coda method (CM) to obtain “nonmodel-based” source spectra and moment estimates from selected broadband recording sites. We found that both methods do well for events that allow the comparison with seismic moment estimates derived from waveform modeling. Also, source spectra obtained from the two methods are very closely matched for most of the events they have in common. We use an F test to examine the trade-off between k and f c picks identified by the direct S-wave method. About half of the events could be constrained to have less than a 50% average uncertainty in f c and k. We used these source spectra solutions to calculate energy and apparent stress and compare these to estimates from the selected “good quality” source spectra from CM. Both studies have values mutually consistent and show a similar increase in apparent stress with increasing moment. This result has added merit due to the independent approaches to calculate apparent stress. We conclude that both methods are at least partially validated by our study, and they both have usefulness for different circumstances of recording local small earthquakes. CM would work well in studies for which there is a broad magnitude range of events and NM works well for local events recorded by band-limited recorders. [ABSTRACT FROM AUTHOR]

The main aim of this study is to statistically investigate the correlation between TOMS/Aerosol Index (AI) remote sensing particulate data and Ground Level (GL) aerosol concentrations. GL fine and coarse particles are collected from watershed area of Buyukcekmece at Marmara region in Istanbul, Turkey (41°0.04′ N; 28°0.59′ E). Randomly collected, 24 hr GL samples are statistically compared with the two years (2002-2003) TOMS/AI data. It is found that there is a significant relationship (R2 = 0.47, p < 0.001) between TOMS/AI data and wintertime GL aerosols. The relation of TOMS/AI data and GL aerosol data are modelled using curvilinear models. Very good agreements between the data sets are obtained. The obtained models are first level exponential model and third level polynominal model for TOMS/AI versus fine and TOMS/AI versus coarse data. R-square values of the models are calculated as 0.92 and 0.67, respectively. [ABSTRACT FROM AUTHOR]

Knowledge on large earthquakes ( M≥ 7.0), geology and fault kinematics is used to analyse conditions that favour isolated seismicity, clustered earthquakes or propagating sequences along the North Anatolian Fault (NAF) and the Sea of Marmara pull-apart. The overall NAF–Marmara fault system is one of the most appropriate on Earth to document fault interactions because reliable information covers almost completely two seismic cycles (the past ∼500 yr). Coulomb stress analysis is used to characterize loading evolution in well-identified fault segments, including secular loading from below and lateral loading imposed by the occurrence of previous earthquakes. Earthquakes along the NAF tend to occur where previous events have increased the stress, but significant isolated events in the Sea of Marmara region (1894, 1912) have occurred, suggesting the secular loading has been the determining factor. Present-day loading appears to be particularly high along the 70-km-long segment located in the central Marmara Sea, southwest of Istanbul. For the 18th century M≥ 7.0 earthquake clusters, we construct scenarios consistent with the tectonic and historical data. We find that scenarios consistent with slip deficit and secular loading distributions (from below) clearly involve a sequence that propagates westward through the Sea of Marmara, despite the structural complexity. However, the inference of a propagating sequence implies that each event has occurred in a segment previously stressed by lateral Coulomb stress interactions. The most likely scenarios for the propagating sequence are also consistent with Coulomb stress interactions between faults with significant normal slip across the Cinarcik basin. Propagating earthquake sequences do not occur every seismic cycle along the NAF. The loading has to be in a particular state of stress close to failure and uniform all along the fault segments to experience propagating earthquake sequences. Non-uniform stress relief during the 18th century sequence explains the occurrence of isolated events in Marmara in 1894 and 1912. As a consequence, the well-known 20th century sequence along the NAF has not propagated as a sequence across the Sea of Marmara. The most linear part of the NAF across northern Turkey behaves as a single fault segment, accumulating stress during hundreds of years and rupturing entirely during very short periods. The Marmara pull-apart fault system behaves as a major geometric complexity, stopping or delaying the progression of earthquake clustering and propagating sequences. Fault zones interact with each other at a very large scale. [ABSTRACT FROM AUTHOR]