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Almost Quasi Clean Rings, Tufan Özdi̇n Jan 2021

Almost Quasi Clean Rings, Tufan Özdi̇n

Turkish Journal of Mathematics

The element $q$ of a ring $R$ is called quasi-idempotent element if $q^2=uq$ for some central unit $u$ of $R$, or equivalently $q=ue$, where $u$ is a central unit and $e$ is an idempotent of $R$. In this paper, we define that the ring $R$ is almost quasi-clean if each element of $R$ is the sum of a regular element and a quasi-idempotent element. Several properties of almost-quasi clean rings are investigated. We prove that every quasi-continuous and nonsingular ring is almost quasi-clean. Finally, it is determined that the conditions under which the idealization of an $R$-module $M$ is almost …


Some Properties Of Second-Order Weak Subdifferentials, Gonca İnceoğlu Jan 2021

Some Properties Of Second-Order Weak Subdifferentials, Gonca İnceoğlu

Turkish Journal of Mathematics

This article deals with second-order weak subdifferential. Firstly, the concept of second-order weak subdifferential is defined. Next, some of its properties are investigated. The necessary and sufficient condition for a second-order weakly subdifferentiable function to have a global minimum has been proved. It has been proved that a second-order weakly subdifferentiable function is both lower semicontinuous and lower Lipschitz.


On The Spectral And Scattering Properties Of Eigenparameter Dependent Discrete Impulsive Sturm-Liouville Equations, Yelda Aygar Küçükevci̇li̇oğlu, Elgi̇z Bayram, Güher Gülçehre Özbey Jan 2021

On The Spectral And Scattering Properties Of Eigenparameter Dependent Discrete Impulsive Sturm-Liouville Equations, Yelda Aygar Küçükevci̇li̇oğlu, Elgi̇z Bayram, Güher Gülçehre Özbey

Turkish Journal of Mathematics

This work develops scattering and spectral analysis of a discrete impulsive Sturm-Liouville equation with spectral parameter in boundary condition. Giving the Jost solution and scattering solutions of this problem, we find scattering function of the problem. Discussing the properties of scattering function, scattering solutions, and asymptotic behavior of the Jost solution, we find the Green function, resolvent operator, continuous and point spectrum of the problem. Finally, we give an example in which the main results are made explicit.


Operators Between Different Weighted Frechet And (Lb)-Spaces Of Analytic Functions, Ersi̇n Kizgut Jan 2021

Operators Between Different Weighted Frechet And (Lb)-Spaces Of Analytic Functions, Ersi̇n Kizgut

Turkish Journal of Mathematics

We study some classical operators defined on the weighted Bergman Frechet space $A^p_{\alpha+}$ (resp. weighted Bergman (LB)-space $A^p_{\alpha-}$) arising as the projective limit (resp. inductive limit) of the standard weighted Bergman spaces into the growth Frechet space $H^\infty_{\alpha+}$ (resp. growth (LB)-space $H^\infty_{\alpha-}$), which is the projective limit (resp. inductive limit) of the growth Banach spaces. We show that, for an analytic self map $\varphi$ of the unit disc $\mathbb{D}$, the continuities of the weighted composition operator $W_{g,\varphi}$, the Volterra integral operator $T_g$, and the pointwise multiplication operator $M_g$ defined via the identical symbol function are characterized by the same condition …


Preservers Of The Local Spectral Radius Zero Of Jordan Product Of Operators, Mhamed Elhodaibi, Somaya Saber Jan 2021

Preservers Of The Local Spectral Radius Zero Of Jordan Product Of Operators, Mhamed Elhodaibi, Somaya Saber

Turkish Journal of Mathematics

Let $\mathscr{B}(X)$ be the algebra of all bounded linear operators on an infinite-dimensional complex Banach space $X$, and denote by $r_{T}(x)$ the local spectral radius of any operator $T \in \mathscr{B}(X)$ at any vector $x \in X$. In this paper, we characterize surjective maps $\phi$ on $ \mathscr{B}(X)$ satisfying $ r_{\phi(T)\phi(A) + \phi(A)\phi(T)}(x)=0$ if and only if $ r_{TA+AT}(x)=0 $


Solving Fractional Differential Equations Using Collocation Method Based On Hybrid Of Block-Pulse Functions And Taylor Polynomials, Yao Lu, Yinggan Tang Jan 2021

Solving Fractional Differential Equations Using Collocation Method Based On Hybrid Of Block-Pulse Functions And Taylor Polynomials, Yao Lu, Yinggan Tang

Turkish Journal of Mathematics

In this paper, a novel approach is proposed to solve fractional differential equations (FDEs) based on hybrid functions. The hybrid functions consist of block-pulse functions and Taylor polynomials. The exact formula for the Riemann--Liouville fractional integral of the hybrid functions is derived via Laplace transform. The FDE under consideration is converted into an algebraic equation with undetermined coefficients by using this formula. A set of linear or nonlinear equations are obtained through collocating the algebraic equation at Newton-Cotes nodes. The numerical solution of the FDE is achieved by solving the linear or nonlinear equations. Error analysis is performed on the …


Soft $\Beta$-Rough Sets And Their Application To Determine Covid-19, Mostafa K. El Bably, Abd El Fattah A. El Atik Jan 2021

Soft $\Beta$-Rough Sets And Their Application To Determine Covid-19, Mostafa K. El Bably, Abd El Fattah A. El Atik

Turkish Journal of Mathematics

Soft rough set theory has been presented as a basic mathematical model for decision-making for many real-life data. However, soft rough sets are based on a possible fusion of rough sets and soft sets which were proposed by Feng et al. [20]. The main contribution of the present article is to introduce a modification and a generalization for Feng's approximations, namely, soft $\beta$-rough approximations, and some of their properties will be studied. A comparison between the suggested approximations and the previous one [20] will be discussed. Some examples are prepared to display the validness of these proposals. Finally, we put …


Existence Results For A Class Of Boundary Value Problems For Fractional Differential Equations, Abdülkadi̇r Doğan Jan 2021

Existence Results For A Class Of Boundary Value Problems For Fractional Differential Equations, Abdülkadi̇r Doğan

Turkish Journal of Mathematics

By application of some fixed point theorems, that is, the Banach fixed point theorem, Schaefer's and the Leray-Schauder fixed point theorem, we establish new existence results of solutions to boundary value problems of fractional differential equations. This paper is motivated by Agarwal et al. (Georgian Math. J. 16 (2009) No.3, 401-411).


Repdigits As Sums Of Two Generalized Lucas Numbers, Sai Gopal Rayaguru, Jhon Jairo Bravo Jan 2021

Repdigits As Sums Of Two Generalized Lucas Numbers, Sai Gopal Rayaguru, Jhon Jairo Bravo

Turkish Journal of Mathematics

A generalization of the well-known Lucas sequence is the $k$-Lucas sequence with some fixed integer $k \geq 2$. The first $k$ terms of this sequence are $0,\ldots,0,2,1$, and each term afterwards is the sum of the preceding $k$ terms. In this paper, we determine all repdigits, which are expressible as sums of two $k$-Lucas numbers. This work generalizes a prior result of Şiar and Keskin who dealt with the above problem for the particular case of Lucas numbers and a result of Bravo and Luca who searched for repdigits that are $k$-Lucas numbers.


Yau-Type Ternary Hom-Lie Bialgebras, Elkadri Abdaoui, Sami Mabrouk, Abdenacer Makhlouf, Sonia Massoud Jan 2021

Yau-Type Ternary Hom-Lie Bialgebras, Elkadri Abdaoui, Sami Mabrouk, Abdenacer Makhlouf, Sonia Massoud

Turkish Journal of Mathematics

The purpose of this paper is to introduce and study $3$-Hom-Lie bialgebras, which are a ternary version of Hom-Lie bialgebras introduced by Yau (2015). We provide their properties, some key constructions and their 3-dimensional classification. Moreover we discuss their representation theory and their generalized derivations and coderivations. Furthermore, a more generalized notion called generalized $3$-Hom-Lie bialgebra is also considered.


The $2$-Rank Of The Class Group Of Some Real Cyclic Quartic Number Fields Ii, Abdelmalek Azizi, Mohammed Tamimi, Abdelkader Zekhnini Jan 2021

The $2$-Rank Of The Class Group Of Some Real Cyclic Quartic Number Fields Ii, Abdelmalek Azizi, Mohammed Tamimi, Abdelkader Zekhnini

Turkish Journal of Mathematics

In this paper, we determine the $2$-rank of the class group of certain classes of real cyclic quartic number fields. Precisely, we consider the case in which the quadratic subfield is $\mathbb{Q}(\sqrt{\ell})$ with $\ell=2$ or a prime congruent to $1\,\pmod8$.


Second Hankel Determinant For Mocanu Type Bi-Starlike Functionsrelated To Shell-Shaped Region, Ni̇zami̇ Mustafa, Gangadharan Murungusundaramoorthy Jan 2021

Second Hankel Determinant For Mocanu Type Bi-Starlike Functionsrelated To Shell-Shaped Region, Ni̇zami̇ Mustafa, Gangadharan Murungusundaramoorthy

Turkish Journal of Mathematics

In this paper, we investigate the coefficient bound estimates, second Hankel determinant, and Fekete-Szegö inequality for the analytic bi-univalent function class, which we call Mocanu type bi-starlike functions, related to a shell-shaped region in the open unit disk in the complex plane. Some interesting special cases of the results are also discussed.


General Rotational $\Xi -$Surfaces In Euclidean Spaces, Kadri̇ Arslan, Yilmaz Aydin, Betül Bulca Jan 2021

General Rotational $\Xi -$Surfaces In Euclidean Spaces, Kadri̇ Arslan, Yilmaz Aydin, Betül Bulca

Turkish Journal of Mathematics

The general rotational surfaces in the Euclidean 4-space $\mathbb{R}^{4}$ was first studied by Moore (1919). The Vranceanu surfaces are the special examples of these kind of surfaces. Self-shrinker flows arise as special solution of the mean curvature flow that preserves the shape of the evolving submanifold. In addition, $\xi -$surfaces are the generalization of self-shrinker surfaces. In the present article we consider $\xi -$surfaces in Euclidean spaces. We obtained some results related with rotational surfaces in Euclidean $4-$space $\mathbb{R}^{4}$ to become self-shrinkers. Furthermore, we classify the general rotational $\xi -$surfaces with constant mean curvature. As an application, we give some …


A Class Of Operators Related To $M$-Symmetric Operators, Fei Zuo, Salah Mecheri Jan 2021

A Class Of Operators Related To $M$-Symmetric Operators, Fei Zuo, Salah Mecheri

Turkish Journal of Mathematics

$m$-symmetric operator plays a crucial role in the development of operator theory and has been widely studied due to unexpected intimate connections with differential equations, particularly conjugate point theory and disconjugacy. For positive integers $m$ and $k$, an operator $T$ is said to be a $k$-quasi-$m$-symmetric operator if $T^{*k}(\sum\limits_{j=0}^{m}(-1)^{j}(^{m}_{j})T^{*m-j}T^{j})T^{k}=0$, which is a generalization of $m$-symmetric operator. In this paper, some basic structural properties of $k$-quasi-$m$-symmetric operators are established with the help of operator matrix representation. In particular, we also show that every $k$-quasi-$3$-symmetric operator has a scalar extension. Finally, we prove that generalized Weyl's theorem holds for $k$-quasi-$3$-symmetric operators.


On 2-Algebras: Crossed R-Modules And Categorical R-Algebras, Zekeri̇ya Arvasi̇, Eli̇f Ilgaz Çağlayan Jan 2021

On 2-Algebras: Crossed R-Modules And Categorical R-Algebras, Zekeri̇ya Arvasi̇, Eli̇f Ilgaz Çağlayan

Turkish Journal of Mathematics

In this work, we describe the category of categorical $R$-algebras and show that a categorical $R$-algebra is a category object in $\mathcal{C=}A\lg _{R}$. By using this property of categorical $R$-algebras, we can give an equivalency between the category of categorical $R$-algebras and the category of crossed $R$-modules and also the category of simplicial $R$-algebras.


Multipliers And $\Mathcal{I}$-Core For Sequences, Mustafa Gülfirat, Ni̇lay Şahi̇n Bayram Jan 2021

Multipliers And $\Mathcal{I}$-Core For Sequences, Mustafa Gülfirat, Ni̇lay Şahi̇n Bayram

Turkish Journal of Mathematics

In this paper we mainly deal with $\mathcal{I}_{c}^{\left( q\right) }-$% convergence. In particular we study bounded multipliers of bounded $\mathcal{% I}_{c}^{\left( q\right) }-$convergent sequences. We also give some $\mathcal{% I}-$core results and characterize the inclusion $K-core\left \{ Ax\right \} \subseteq \mathcal{I}-core\left \{ x\right \} $ for bounded sequences $% x=\left( x_{n}\right) $.


Banach Algebra Structure On Strongly Simple Extensions, Sara El Kinani Jan 2021

Banach Algebra Structure On Strongly Simple Extensions, Sara El Kinani

Turkish Journal of Mathematics

We consider strongly simple extensions of unitary commutative Banach algebras. We study these Banach algebra structure without assuming the continuity of the canonical injection. The link of the integrality with these extensions is studied. Several algebraic results are also obtained.


Solvability, Stability, Smoothness And Compactness Of The Set Of Solutions For A Nonlinear Functional Integral Equation, Nguyen Dat Thuc, Le Thi Phuong Ngoc, Nguyen Thanh Long Jan 2021

Solvability, Stability, Smoothness And Compactness Of The Set Of Solutions For A Nonlinear Functional Integral Equation, Nguyen Dat Thuc, Le Thi Phuong Ngoc, Nguyen Thanh Long

Turkish Journal of Mathematics

This paper is devoted to the study of the following nonlinear functional integral equation \begin{equation} f(x)=\sum\limits_{i=1}^{q}\alpha _{i}(x)f(\tau_{i}(x))+\int_{0}^{\sigma_{1}(x)}\Psi \left( x,t,f(\sigma _{2}(t)),\int_{0}^{\sigma_{3}(t)}f(s)ds\right) dt+g(x),\text{ }\forall x\in \lbrack 0,1], \tag{E} \label{E} \end{equation} where $\tau _{i},$ $\sigma _{1},$ $\sigma _{2},$ $\sigma _{3}:[0,1]\rightarrow \lbrack 0,1];$ $\alpha _{i},$ $g:[0,1]\rightarrow \mathbb{R};$ $\Psi :[0,1]\times \lbrack 0,1]\times \mathbb{R}^{2}\rightarrow \mathbb{R}$ are the given continuous functions and $f:[0,1]\,\rightarrow \mathbb{R}$ is an unknown function. First, two sufficient conditions for the existence and some properties of solutions of Eq. (E) are proved. By using Banach's fixed point theorem, we have the first sufficient condition yielding existence, uniqueness and stability of the solution. By applying …


Synergism And Antagonism In Plant Acclimation To Abiotic Stress Combinations, Karl-Josef Dietz Jan 2021

Synergism And Antagonism In Plant Acclimation To Abiotic Stress Combinations, Karl-Josef Dietz

Turkish Journal of Botany

Acclimation of plants to their environment involves mechanisms at all molecular levels and only the complete temporal and spatial pattern adequately describes the acclimation state. The diversity of physiological states realized in plants increases by the essentially infinite combinations of abiotic and biotic stresses, considering duration, impact order, and strength. The interference between stressors involves phenomena of synergism, antagonism, and indifference. This review exemplarily sketches principles of interference considering posttranslational modifications, the formation of molecular assemblies in regulosomes, the regulation of gene expression, and the vast number of other posttranscriptional controls e.g., in RNA processing and recruitment to ribosomes. Small …


Volvopluteus And Pluteus Section Pluteus (Agaricales: Pluteaceae) In Turkey Based Onmorphological And Molecular Data, Oğuzhan Kaygusuz, İbrahi̇m Türkekul, Henning Knudsen, Nelson Menolli Jr. Jan 2021

Volvopluteus And Pluteus Section Pluteus (Agaricales: Pluteaceae) In Turkey Based Onmorphological And Molecular Data, Oğuzhan Kaygusuz, İbrahi̇m Türkekul, Henning Knudsen, Nelson Menolli Jr.

Turkish Journal of Botany

Pluteus and Volvopluteus are two closely related genera of Pluteaceae that comprise saprotrophic fungi. Although the genera have been well-studied in Europe and North and South America, the diversity of Pluteus, mainly Pluteus sect. Pluteus, and Volvopluteus in Turkey is poorly known due to insufficient morphological descriptions and a lack of DNA sequence data. In this study, the diversity of Pluteus sect. Pluteus and Volvopluteus in Turkey is evaluated by employing both morphological features and phylogenetic approaches. A general phylogeny of Pluteus sect. Pluteus based on sequences of nuc rDNA internal transcribed spacer (ITS1-5.8S-ITS2 = ITS) region is presented and …


Running Sigmas Analysis Of Sampled Molecular Paraphyly In Pottiaceae (Bryophyta), Richard Zander Jan 2021

Running Sigmas Analysis Of Sampled Molecular Paraphyly In Pottiaceae (Bryophyta), Richard Zander

Turkish Journal of Botany

A spreadsheet dealing with standard deviations allows statistical examination of continuous variables associated with paraphyly in systematics, with examples in the Pottiaceae (Bryophyta). Outlier values in taxonomic representation of distribution with the structure of (w-)x-y(-z) of continuous variables can be empirically supported. The use of the geometric mean and intuitional estimation is reexamined. Published reports of the distance between maximally distant exemplars of individual paraphyletic species in molecular cladograms in several studies were reevaluated as metadata. Levels of standard deviations were assigned with the Running Sigmas spreadsheet. A spike in width of exemplars of a paraphyletic species of a moss …


Projecting The Course Of Covid-19 In Turkey: A Probabilistic Modeling Approach, Aybar Can Acar, Ahmet Görkem Er, Hüseyi̇n Cahi̇t Burduroğlu, Seher Nur Sülkü, Yeşi̇m Aydin Son, Levent Akin, Serhat Ünal Jan 2021

Projecting The Course Of Covid-19 In Turkey: A Probabilistic Modeling Approach, Aybar Can Acar, Ahmet Görkem Er, Hüseyi̇n Cahi̇t Burduroğlu, Seher Nur Sülkü, Yeşi̇m Aydin Son, Levent Akin, Serhat Ünal

Turkish Journal of Medical Sciences

Background/aim: The COVID-19 pandemic originated in Wuhan, China, in December 2019 and became one of the worst global health crises ever. While struggling with the unknown nature of this novel coronavirus, many researchers and groups attempted to project the progress of the pandemic using empirical or mechanistic models, each one having its drawbacks. The first confirmed cases were announced early in March, and since then, serious containment measures have taken place in Turkey. Materials and methods: Here, we present a different approach, a Bayesian negative binomial multilevel model with mixed effects, for the projection of the COVID-19 pandemic and we …


Current Community Transmission And Future Perspectives On The Covid-19 Process, Seyhan Türk, Can Türk, Ümi̇t Yavuz Malkan, Eli̇f Sena Temi̇rci̇, Mustafa Çağri Peker, İbrahi̇m Celaletti̇n Haznedaroğlu Jan 2021

Current Community Transmission And Future Perspectives On The Covid-19 Process, Seyhan Türk, Can Türk, Ümi̇t Yavuz Malkan, Eli̇f Sena Temi̇rci̇, Mustafa Çağri Peker, İbrahi̇m Celaletti̇n Haznedaroğlu

Turkish Journal of Medical Sciences

Background/aim: COVID-19 syndrome due to the SARS-CoV-2 virus is a currently challenging situation ongoing worldwide. Since the current pandemic of the SARS-CoV-2 virus is a great concern for everybody in the World, the frequently asked question is how and when the COVID-19 process will be concluded. The aim of this paper is to propose hypotheses in order to answer this essential question. As recently demonstrated, SARS-CoV-2 RNAs can be reverse-transcribed and integrated into the human genome. Our main hypothesis is that the ultimate aim of the SARS-CoV-2 virus is the incorporation to human genome and being an element of the …


Electrocardiography Clues In Assessment Of Patients With Premature Ventricularcontractions, Ahmet Akdi̇, Bahar Teki̇n Tak, Eli̇f Hande Özcan Çeti̇n, Mehmet Serkan Çeti̇n, Çağri Yayla Jan 2021

Electrocardiography Clues In Assessment Of Patients With Premature Ventricularcontractions, Ahmet Akdi̇, Bahar Teki̇n Tak, Eli̇f Hande Özcan Çeti̇n, Mehmet Serkan Çeti̇n, Çağri Yayla

Turkish Journal of Medical Sciences

Background/aim: Some electrocardiography (ECG) parameters such as Tp-e interval, Tp-e / QT ratio, fragmented QRS (fQRS), and heart rate variability (HRV) are related to cardiovascular mortality and morbidity. We aim to investigate the relation between premature ventricular contraction burden and these parameters on 24-h ECG recording. Materials and methods: The study is a retrospective investigation of the 24-h Holter ECG and echocardiography of 199 patients who underwent the procedures due to complaints of palpitation. A frequency of < 10% PVCs / 24 h was classified as seldom group (98 patients), while > 10% PVCs / 24 h was designated as frequent group (101 patients). Results: Tp-e interval was significantly longer (62 [54-78] vs 75 [60-84], …


Earthquake History Of The Yatağan Fault (Muğla, Sw Turkey): Implications For Regionalseismic Hazard Assessment And Paleoseismology In Extensional Provinces, Mehran Basmenji, Hüsnü Serdar Akyüz, Erdem Kirkan, Murat Ersen Aksoy, Gülsen Uçarkuş, Nuretti̇n Yakupoğlu Jan 2021

Earthquake History Of The Yatağan Fault (Muğla, Sw Turkey): Implications For Regionalseismic Hazard Assessment And Paleoseismology In Extensional Provinces, Mehran Basmenji, Hüsnü Serdar Akyüz, Erdem Kirkan, Murat Ersen Aksoy, Gülsen Uçarkuş, Nuretti̇n Yakupoğlu

Turkish Journal of Earth Sciences

The southern part of the Western Anatolia Extensional Province is governed by E-W-trending horst-graben systems and NW-SE-oriented active faults. The NW-striking Yatağan Fault is characterised by an almost pure normal sense of motion with a minor dextral strike slip component. Although the settlements within the area have been affected by several earthquake events since ancient times (~2000 BCE), the earthquake potential and history of the Yatağan Fault has remained unknown until a few years ago. Considering the growing dense population within the area, paleoseismology studies were conducted in order to illuminate the historical earthquake activity on the Yatağan Fault. Two …


Time-Dependent Model For Earthquake Occurrence And Effects Of Design Spectra Onstructural Performance: A Case Study From The North Anatolian Fault Zone, Turkey, Ercan Işik, Yunus Levent Eki̇nci̇, Ni̇lgün Lütfi̇ye Sayil, Aydin Büyüksaraç, Mehmet Ci̇han Aydin Jan 2021

Time-Dependent Model For Earthquake Occurrence And Effects Of Design Spectra Onstructural Performance: A Case Study From The North Anatolian Fault Zone, Turkey, Ercan Işik, Yunus Levent Eki̇nci̇, Ni̇lgün Lütfi̇ye Sayil, Aydin Büyüksaraç, Mehmet Ci̇han Aydin

Turkish Journal of Earth Sciences

We have investigated the time-dependent seismicity model of the earthquake occurrence on a regional basis through the North Anatolian Fault Zone (NAFZ). To that end, the studied region has been subdivided into 7 seismogenic zones considering the seismotectonic criteria, and then regional time and magnitude predictable (RTIMAP) model has been performed. Intervened times and magnitudes of main shocks produced in each zone have predictive properties defined by the RTIMAP. The probabilities of the next main shocks in 5 decades and the magnitudes of the next events have been estimated using the formation time and magnitude of the past events in …


Peritectic Assemblage Entrainment And Mafic-Felsic Magma Interaction In Thelate Oligocene-Early Miocene Karadağ Pluton In The Biga Peninsula, Northwest Turkey:Petrogenesis And Geodynamic Implications, Namik Aysal, Abdullah Si̇nan Öngen, Sabah Yilmaz Şahi̇n, Cem Kasapçi, Nurullah Hani̇lçi̇, Irena Peytcheva Jan 2021

Peritectic Assemblage Entrainment And Mafic-Felsic Magma Interaction In Thelate Oligocene-Early Miocene Karadağ Pluton In The Biga Peninsula, Northwest Turkey:Petrogenesis And Geodynamic Implications, Namik Aysal, Abdullah Si̇nan Öngen, Sabah Yilmaz Şahi̇n, Cem Kasapçi, Nurullah Hani̇lçi̇, Irena Peytcheva

Turkish Journal of Earth Sciences

The Hellenic subduction system governs the entire Aegean region through the creation of a migrating magmatic arc that has existed since the beginning of the Early Cenozoic. The Karadağ Pluton is situated in the NW part of Turkey and represents one of the distinct snapshots of this subduction system during the Late Oligocene-Early Miocene Period.iod. It consists of 2 major lithological units, based on their petrographic and geochemical features, comprising: 1) main plutonic facies (SiO2 < 70 wt.%) that are dominated by hornblende- and biotite-bearing monzogranite, quartz monzonite, and granodiorite, and 2) late-stage more felsic facies (SiO2 > 70 wt.%) that are represented by cordierite-free and cordierite-bearing leucogranites. Zircon U-Pb laser ablation inductively-coupled plasma mass spectrometry and K-Ar dating revealed crystallization and cooling …


Alaşehir Type - Rolling Hinge Mechanism In The Northern Margin Of Büyük Menderes Graben: Evidence From Seismic Reflection And Recent Thermochronological Data, Fevzi̇ Mert Türesi̇n, Gürol Seyi̇toğlu Jan 2021

Alaşehir Type - Rolling Hinge Mechanism In The Northern Margin Of Büyük Menderes Graben: Evidence From Seismic Reflection And Recent Thermochronological Data, Fevzi̇ Mert Türesi̇n, Gürol Seyi̇toğlu

Turkish Journal of Earth Sciences

Isotopic and thermochronological data were recently obtained from the footwall of the Büyük Menderes detachment ranges from 29.0 ± 1.9 Ma (ZFT) to 1.6 ± 0.2 Ma (Ap U - Th / He), and they can be grouped in three different time intervals. These results are well explained by the Alaşehir type-rolling hinge mechanism, which suggests active rotated initial normal fault during successive normal fault development of the graben formation. This paper suggests that the Alaşehir type-rolling hinge mechanism is applicable to the Büyük Menderes graben by using field observations, published isotopic / thermochronological and subsurface data. It also contributes …


12th June 2017 Offshore Karaburun-Lesvos Island Earthquake Coseismic Deformation Analysis Using Continuous Gps And Seismological Data, Hasan Yildiz, Ayça Çirmik, Oya Pamukçu, Özkan Cevdet Özdağ, Tolga Gönenç, Muzaffer Kahveci̇ Jan 2021

12th June 2017 Offshore Karaburun-Lesvos Island Earthquake Coseismic Deformation Analysis Using Continuous Gps And Seismological Data, Hasan Yildiz, Ayça Çirmik, Oya Pamukçu, Özkan Cevdet Özdağ, Tolga Gönenç, Muzaffer Kahveci̇

Turkish Journal of Earth Sciences

Understanding the tectonic mechanism generated by the earthquakes and faults is possible only if the preseismic, coseismic and postseismic crustal deformation related to the earthquakes is determined properly. By the analysis of continuous GPS (CGPS) coordinate time series, it is possible to estimate the crustal deformation. Besides, accelerometer records at strong motion stations (SMSs) may support the CGPS-based estimates. In this study, CGPS coordinate time series were analyzed in comparison with the accelerometer records for clarifying the coseismic deformation caused by the earthquake occurred in the surrounding of Lesvos fault located in the northern part of Karaburun within the active …


Classification Of Plutonic Rock Types Using Thin Section Images With Deep Transfer Learning, Özlem Polat, Ali̇ Polat, Taner Eki̇ci̇ Jan 2021

Classification Of Plutonic Rock Types Using Thin Section Images With Deep Transfer Learning, Özlem Polat, Ali̇ Polat, Taner Eki̇ci̇

Turkish Journal of Earth Sciences

Classification of rocks is one of the basic parts of geological research and is a difficult task due to the heterogeneous properties of rocks. This process is time consuming and requires sufficiently knowledgeable and experienced specialists in the field of petrography. This paper has a novelty in classifying plutonic rock types for the first time using thin section images; and proposes an approach that uses the deep learning method for automatic classification of 12 types of plutonic rocks. Convolutional neural network based DenseNet121, which is one of the deep learning architectures, is used to extract the features from thin section …