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We have restored the geometries of suture zones that involved various continental blocks in central Anatolia during the Neogene, using palaeomagnetic data. Previously, the Kırşehir Block was proposed to be an NNE-SSW striking tectonic block broken into three fragments that they underwent clockwise rotations in the north and counter-clockwise rotations in the south during the Palaeogene, due to collision and N-S shortening of the Kırşehir Block between Tauride-Menderes Block in the south and the Pontides in the north. Our new results point out five distinct Neogene tectonic domains with distinct rotation patterns that indicate the rotational deformation of Central Anatolia is far more complex than generally presumed. Among these, 1) Kırıkkale-Bala Domain is rotated ~18° clockwise, 2) the Tuz Gölü Domain underwent ~14° counter-clockwise rotation, 3) the Alcı-Orhaniye Domain rotated ~35° counter-clockwise sense, 4) the Northern Haymana Domain underwent ~12° counter-clockwise rotation while 5) the Southern Haymana Domain underwent very small (~5° clockwise) net rotation since the early Miocene. The results also indicated that pre-Neogene configuration of the Izmir-Ankara Suture Zone was striking almost E-W while Inner-Tauride and Ankara-Erzincan suture zones were almost N-S in the study area. In addition, the fault zones that define the these domains extend from the Kırşehir Block into the over-riding blocks (Pontides) continuously without any deflection indicating that they were active during the Neogene and fragmented and dislocated the suture zones in the region. [ABSTRACT FROM AUTHOR]

Due to the increasing number of vehicles in the world, the confusion and congestion problems observed at signalized intersections in undeveloped and developing countries caused an increase in interest for rearrangement. The design of intersection geometries is very important to develop delay and queue length calculation methods considering conditions. In this study, the situation in Antalya/Turkey, which has geometric problems at urban intersections, has been examined for six signalized intersections. Additionally, HCM (2010) and Australia (Akçelik) methods, which are widely used delay and queue length methods, are examined for the calculation problems at intersections for undeveloped and developing countries considering their traffic culture. According to the results, when the intersection-based MAPE values are averaged for six intersections, the method with the lowest average error (64.5%) for delay is found in HCM 2010, and the method with the lowest average error (40.9%) for queue length is found HCM 2010 again. It is seen that selected queue length methods measure the current situation at intersections with less error than used delay methods, but the fact that value of errors are quite high. It indicates that the selected methods are not directly applicable for intersections. Results clearly reveal the necessity to develop specific delay and queue length methods for undeveloped and developing countries where there are geometric indisciplines at intersection legs. [ABSTRACT FROM AUTHOR]

Introduction: This study examines the spatial abilities of middle school students with visual impairments (i.e., blindness and low vision) in the context of spatial visualization. The study also aims to examine the strategies used by such students in solving questions requiring spatial ability. Methods: Participants comprised eight students with visual impairments attending the 8th grade of a school in Ankara, Turkey, which teaches students with visual impairments. The data collection tool is composed of eight questions under the guidance of the definition for spatial visualization. Question types belonging to the spatial visualization subcomponent were organized in four topics: 2D rotation, 3D rotation, paper folding, and cube folding. Results: It was observed that students with visual impairments used mental rotation and key feature strategies for 2D rotation questions. They used the key feature strategy for 3D rotation questions and the mental manipulation strategy for cube folding and paper folding questions. Discussion: In this study, it was identified that strategies used by students with visual impairments show similarities with spatial strategies defined in the literature as used by students without visual impairments. Of all the other types of questions, the most successful question of students with visual impairments is the paper folding question. Implications for practitioners: The results of this article can help teachers become aware of the kind of difficulties that students with visual impairments encounter when they try to solve questions that require spatial ability. [ABSTRACT FROM AUTHOR]

The numerical method presented here is simple, fast and designed to determine automatically the depth, shape, polarization angle and electric dipole moment from residual self-potential (SP) anomalies due to ore bodies of simple geometry. The calculation needs only four characteristic points defining the anomaly and their corresponding distances on the anomaly profile. The inverse problem of depth determination from residual SP anomaly is solved by a linear equation for each shape factor. Using all successful combinations of the four characteristic points and their corresponding distances, a procedure is developed and practiced for automated determination of the best shape factor and depth of the buried body from SP data. The procedure is based on calculating the standard deviation of depths at each shape factor. Knowing the optimum depth and shape of the buried structure, formulas and procedures are also given for estimating the best polarization angle and the electric dipole moment. Because the present method uses all successful combinations of data points, it has the capability of enhancing the interpretation results. The method is tested on three noisy synthetic examples and applied on two field examples from Indonesia and Turkey. The estimated model parameters are always found to be in good agreement with proposed or actual values. [ABSTRACT FROM AUTHOR]

When we look at the theoretical relationships between the three types of geometry, we find that the most primitive type is topology and that both Euclidean and projective geometry are derived from this earlier type. Therefore, Piaget described the first stage or level of understanding geometry as topological understanding. In this study, the geometric thinking conditions of mathematics teacher candidates were examined and what they think about the topology course was determined by surveying their opinions about the undergraduate courses. The participants of the study consisted of 36 teacher candidates studying in the Mathematics Department of the Faculty of Science attached to a university in Turkey. The findings of the study revealed that none of the teacher candidates used topological thinking to solve the questions in the data collection instrument. Those candidates who considered topology as an abstract course did not associate topology with geometry. A thorough understanding of the meaning of topology and topological thought is an advantage to young children as well as college‐age students; improving mathematics curricula on this topic, particularly at the graduate level, will ensure that all future teachers are appropriately trained for their future responsibility of educating others. We believe that it is necessary to give Topology and topological thought the place they deserve in the educational process. [ABSTRACT FROM AUTHOR]

The 2017 July 20, M w6.6 Bodrum–Kos earthquake occurred in the Gulf of Gökova in the SE Aegean, a region characterized by N–S extension in the backarc of the easternmost Hellenic Trench. The dip direction of the fault that ruptured during the earthquake has been a matter of controversy where both north- and south-dipping fault planes were used to model the coseismic slip in previous studies. Here, we use seismic (seismicity, main shock modelling, aftershock relocations and aftershock mechanisms using regional body and surface waves), geodetic (GPS, InSAR) and structural observations to estimate the location, and the dip direction of the fault that ruptured during the 2017 earthquake, and the relationship of this event to regional tectonics. We consider both dip directions and systematically search for the best-fitting locations for the north- and south-dipping fault planes. Comparing the best-fitting planes for both dip directions in terms of their misfit to the geodetic data, proximity to the hypocenter location and Coulomb stress changes at the aftershock locations, we conclude that the 2017 earthquake ruptured a north-dipping fault. We find that the earthquake occurred on a 20–25 km long, ∼E–W striking, 40° north-dipping, pure normal fault with slip primarily confined between 3 and 15 km depth, and the largest slip exceeding 2 m between depths of 4 and 10 km. The coseismic fault, not mapped previously, projects to the surface within the western Gulf, and partly serves both to widen the Gulf and separate Kos Island from the Bodrum Peninsula of SW Anatolia. The coseismic fault may be an extension of a mapped, north-dipping normal fault along the south side of the Gulf of Gökova. While all of the larger aftershocks are consistent with N–S extension, their spatially dispersed pattern attests to the high degree of crustal fracturing within the basin, due to rapid trenchward extension and anticlockwise rotation within the southeastern Aegean. [ABSTRACT FROM AUTHOR]

The sinistral Malatya-Ovacık Fault Zone (MOFZ) is one of the outstanding intraplate deformation belts within Anatolia. The 165-km-long, NE-SW-striking Malatya Fault (MF), which constitutes the southern section of the MOFZ, is separated into five segments according to its surface geometry. These segments have evident morphotectonic features that reflect long- and short-term fault activity, such as morphologic structures offset by as little as 7 m and as much as 7.3 km. This study provides results from the first paleoseismological investigations on the MF. We find that the last earthquake occurred between 965 and 549 BCE and calculate a recurrence interval of 2275 ± 605 years from evidence for four paleo-events over the last 10 ka. Considering fault segmentation and our paleoseismological data, we propose that the accumulated strain on the MF may cause a destructive earthquake (M = 7.4) in the near future. Our results support the hypotheses that the MF and other NW-striking dextral and NE-striking sinistral strike-slip faults within the eastern part of Anatolia are plate boundary-related, active deformational structures. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate the effect of teaching activities focused on the inclusive and exclusive definition of quadrilaterals on the associative skills of 7th grade students. The sample of the study consists of 31, 7th grade students; 16 students in the experimental group and 15 students in the control group. The study conducted in a public school in Middle Black Sea Region in Turkey. The design of the study was pretest - post-test control group week experimental design. As a data collection tool, an achievement test developed by the researchers under the guidance of expert opinion based on the literature. This test used as pre-test and post-test. The study lasted in 5 weeks. Instruction focused on inclusive definition of quadrilaterals in experimental group while exclusive definition of quadrilaterals in control group. T-test analysis was used to find the difference between pre-test and post-test scores via SPSS program. According to findings, there was no statistically significant difference between the pre-test scores of the experimental group and the control group, but there was a statistically significant difference between the test group and the control group in favor of the experimental group at the end. As a result, it can be said that associative instruction has positive effects on student achievement in quadrilaterals. [ABSTRACT FROM AUTHOR]

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]

The western termination of the 1999 İzmit earthquake still remains as an intriguing problem for researchers and the people residing around the Sea of Marmara. There have been numerous of shore mapping and modelling studies performed in the Gulf of İzmit. However, the main debate about the western termination of the 1999 İzmit surface rupture is linked to the Hersek Peninsula and corresponding fault geometry. We focused our efforts at resolving the fault geometry on the Hersek Peninsula by applying geological mapping, geomorphic analyses, palaeoseismic trenching and geophysical surveys. Our studies reveal that the North Anatolian Fault forms a restraining stepover and did not experience surface rupture during 1999 İzmit earthquake in the vicinity of Hersek Peninsula. We tested this fault geometry with a finite element model in half elastic space and correlated the results successfully with the existing topography. In addition, we ran a simple Coulomb model to explain the possible cause of surface rupture termination at this specific location. Our studies, combined with detailed of shore bathymetry data, suggest that the restraining step of the North Anatolian Fault on the Hersek Peninsula is capable of creating an efficient earthquake rupture barrier. [ABSTRACT FROM AUTHOR]

In this study, it is aimed to investigate buildings' solar exposure in the existing urban texture in Elazig city center. For this purpose we implemented an application study on some specific points which exist on Gazi Street and some branch streets which have remarkable structural density. It is established that there is an inappropriate proportion between building height and street width in Elazig. So that building facades exposure less solar radiation. It is also determined that SVF values that depends to the proportion between street width and building height changes between 0.574 and 0.287. SVF can only be used to compare solar exposure of the same oriented canyons or a point in the canyon. Surface temperature measurements changing between 22.3 °C and 8.9 °C depending to direction of the canyons have also been done. Results of the measurements for surface temperatures show that badly proportioned street geometry affects surface temperatures in a canyon. Moreover, energy consumption to achieve indoor comfort conditions in buildings can change significantly related to street geometry. Therefore, solar radiation effects should be taken into consideration at the design stage of new settlements. [ABSTRACT FROM AUTHOR]

ABSTRACT The structural evolution of the Miocene to Recent Gediz Graben is intimately related to the evolution of its southern margin. This margin is shaped by a time-transgressive, composite structure that possesses flat-ramp geometry with three separate dip domains: a low-angle shallow segment; a steeper middle segment; and a low-angle deeper segment. This geometry was probably produced by one of two mechanisms, which operated perpendicular to the general trend of the graben, resulting in gradual back-rotation followed by abandonment of the shallow segment as it was dissected by the high-angle normal fault(s). The geometry of the southern margin structure is not simple along-strike. It includes broad undulations and discrete fault segments, developed by large-scale fault growth processes through segment linkage. The along-strike growth of the southern margin-bounding structure is responsible for the composite character of the Gediz Graben and controls the observed stratigraphic variability. Two sub-basins aligned with the major segments of the southern graben margin structure have been investigated. The Salihli and Alaşehir sub-basins comprising 3000 m sedimentary thickness are separated by an intervening basement high, that is covered by a thin veneer of post-Miocene sediments. The two sub-basins, which evolved as isolated basins during most of the graben history, amalgamated during post-Miocene time to form the composite configuration of the graben. There is a general east to west trend of growth for the Gediz Graben. [ABSTRACT FROM AUTHOR]

This paper discusses the Archimath programme, which was designed to develop awareness of the built environment in elementary school students, and to initiate an effort to improve it. Acknowledging the relationship between education and awareness of the environment, the programme was constructed for use with elementary school students selected from fourth to eighth grades, as an integrated mathematics and architecture programme. It includes topics from an introductory course for architecture majors and from the elementary mathematics curriculum. The programme was implemented in several pilot schools in Istanbul and was evaluated in accordance with activity sheets, pre- and post-perception tests, and the views and comments of the teachers who carried out the programme. It was revised and reorganized in accordance with this feedback and then implemented again on different groups of students in the selected schools. This paper discusses how the programme was conceived and developed. [ABSTRACT FROM AUTHOR]

The article presents information about the third symposium on geometry that was held in Eski&#015F;ehir-Osmangazi University in Turkey from July 3-6, 2005. The Scientific Committee which led the Symposium consisted of K. Arslan, S. Bilir, A. Ergin, R. Kaya and colleagues. Some of the topics discussed at the conference include Ricci-symmetric structures of a K-manifold with Lorentz metric and symmetric structures on a Riemannian manifold.

The article presents information on the Third Symposium on Geometry, held at the Eskişehir-Osmangazi University in Turkey on July 3 to 6, 2005. The symposium was lead by a Scientific Committee consists of K. Arslan, S. Bilir, A. Ergin and R. Kaya and their colleagues. Topics discussed in the symposium include weakly symmetric and weakly Ricci-symmetric K-manifolds with Lorentz metric, weakly and pseudo concircularsymmetric structures on a Riemannian manifold.

A long (∼15 km) and narrow (∼4 km) offshore positive temperature anomaly (∼1.7° C) is observed in the Landsat Thematic Mapper (TM) thermal infrared (TIR) image acquired the day following the large İzmit earthquake (Mw 7.4) of 17 August 1999, in eastern Marmara Sea, Turkey. The earthquake was generated along the North Anatolian Fault, which ruptured for about 150 km, and the anomaly formed at the western termination of this rupture. Discussions of this anomaly may develop by processes different than the seismic activity and considerations on fault geometry and sea bathymetry characteristics suggest that the anomaly may result from aftershock activity near the western end of the earthquake fault. The formation of the anomaly requires the addition of a large quantity of hot waters to the sea. The ascent to the sea bottom of fault-driven hot fluids (seismic pumping) and formation of thermal plumes may be the processes by which the sea surface temperature increased. Recent works and the present study suggest that TIR data analysis may be used as a tool in seismological studies. [ABSTRACT FROM AUTHOR]

Abstract: Gravity anomalies always include the total effects (combination of the structures which have different densities and depths) of the study area and beyond. And the well-known non-uniqueness of potential field modelling may lead to very different interpretation results. The finite element method (FEM), which has been used in potential field interpretation for decades, makes complex problems to be solved easily and accurately. The first step of FEM is to identify the elements and then to decide on the boundary of the solution space. In this step, the solution space is divided into elements. After determination of the geometrical structure of the solution space, the most suitable elements should be chosen for this geometrical structure. The agreement between the geometry and the elements is quite important for the convergence to the best possible solution. In this work, the methods of trend analysis, filtering, analytical continuation and FEM were applied to a theoretical model and to gravity data from western Turkey to produce the regional and the residual anomalies. The results were compared and it was found that the FEM produced more accurate results than other methods did. [Copyright &y& Elsevier]

Weathering processes cause important changes in rock porosity. Besides porosity, distribution of pore sizes is significant for the identification of changes due to rock weathering and its effects on fabric. The formation of secondary porosity in different types of rock taken from different parts of Turkey was examined and the results are presented in this paper. The aim of this study was to observe changes in porosity due to weathering. Effective porosity, mercury intrusion porosimetry, and optical and scanning electron microscopy were used to evaluate the changes in pore geometry of the rocks. Additionally, the dry density, water absorption and uniaxial compressive strength of the rocks at different weathering stages were determined. Analysis of experimental data showed that microstructure of the rocks in relation to weathering is the main feature, which controls their physical and mechanical properties. The study revealed that fabric characteristics, particularly the pore and fracture geometry are very important characteristics for assessment of the behaviour of weathered rock. [Copyright &y& Elsevier]

The surface expression of the North Anatolian Fault between the Sea of Marmara and the Gulf of Saros, Turkey was determined using Landsat 5 Thematic Mapper (TM) and Système Probatoire de l'Observation de la Terre (SPOT) high resolution visible (HRV) Panchromatic images and a digital elevation model (DEM) based on 1 : 25 000 scale topographic maps. The remotely sensed data had been enhanced to reveal linear details. Between Gaziköy (Marmara Shore) and Saros two small releasing steps were identified, one to the east of Mürseli village and the other between Mürseli and Yayaköy villages. Hitherto, a single straight fault line had been drawn between Gaziköy and Saros on the geological map of this region. Between the Yeniköy and Sofular villages, the fault strike bends ∼7° further to the SE. The course of the fault between the Sea of Marmara and the Gulf of Saros is, therefore, more complicated than formerly believed and this is probably because the fault has utilized the pre-existing structures of the Neo-Tethyan subduction-accretion complex. [ABSTRACT FROM AUTHOR]

Beneath the Marmara Sea, Turkey, the Main Marmara Fault (MMF), the offshore part of the North Anatolian Fault (NAF), is a well-known seismic gap for future M > 7 earthquakes. However, its detailed fault geometry and microearthquake activity have been debated for several decades. Using data acquired from long-term ocean bottom seismograph (OBS) observations, we made precise hypocenter estimations based on 3-D Vp and Vs velocity structures and assessed the fault geometry beneath the western and central parts of the MMF. The results indicate a segmentation boundary between the near-vertical western part and the south-dipping eastern part located around 28.10°E. Enriched OBS locations indicate microseismicity along both the inner and outer boundary faults of the Central Basin, especially on the western side. A comparison with previously published results suggests that the seismicity pattern has not changed for at least two years, between 2014 and 2016. Using a combined dataset of this and previous studies, lateral variations in the dip angle along the MMF fault segment from 27.4°E to 28.8°E were investigated. Based on this, we depicted on-fault seismicity along the MMF and defined three inactive areas of microseismicity. Two are located in the western segment, corresponding to the rupture area of the 1912 Ms. 7.4 earthquake, and the other, the largest, is located on the eastern segment. From a comparison of previous seismic and geodetic studies, it is considered that this area is a fully locked zone and has the potential for large earthquakes. Having compared the difference between hypocenter locations determined from OBSs and land-based stations, it is proposed that the epicentral locations of the mainshock and aftershocks of the September 26, 2019, M 5.7 earthquake are located much closer to the MMF than locations reported from only land-based results. • A segmentation boundary on the Main Marmara Fault is identified beneath the Central Basin. • Both inner and outer boundary faults of the Central Basin are developed in the western Central Basin. • Zones of no seismicity beneath the Kumburgaz Basin have the potential for a large earthquake. • The focal area of the September 2019 M 5.7 event was close to the Main Marmara Fault. [ABSTRACT FROM AUTHOR]

The Neogene succession in the western margin of Çankırı Basin is fragmented by a NNE-trending tectonic sliver having normal faulted western and thrusted eastern margins. This newly recognized E-vergent sliver was created by the NW–SE compression due to the North Anatolian and Kırıkkale–Erbaa Fault zones following late Pliocene, accommodating the internal deformation of the Anatolian plate. Determinations of the Kılçak, Kumartaş and Hançili formations on both sides of this tectonic sliver invalidate the stratigraphical, structural and basin evolution models previously proposed by Kaymakçı. Terra Nova, 00, 1–3, 2004 [ABSTRACT FROM AUTHOR]

As any ordinary person knows, the shortest distance between two points is a straight line. What, then, is the shortest distance between three points? Four points? The study reported in this article deals with the observed actions of Turkish student mathematics teachers as they were working with minimal network problems. Having analysed the mathematization processes of student mathematics teachers in computerized environment, I describe here how new mathematical relationships can be discovered from real-world situations. The results showed that using real world situations in computerized classrooms leaves the doors open for the students for decision making, experimental verification, conjecturing and even for construction of proofs. [ABSTRACT FROM AUTHOR]