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The Tuzla Fault (TF), considered one of the most important seismic sources in İzmir province, is defined as a strike–slip fault with N10E–N60E striking between Gaziemir and Doğanbey districts. A 50-km-long fault consists of three segments which are, from north to south Çatalca, Orhanlı, and Doğanbey segments. Recent studies claim that the part of the TF extending to Kuşadası Bay is also in a kinematic relationship with the Samos Fault that caused an earthquake on 30 October 2020 (Mw = 6.9). In this study, in order to analyse the historical behaviour of the fault, three trench-based palaeoseismology studies across the fault scarp were conducted on three geometric segments of the TF. Palaeoseismology findings show that seven historic/prehistoric earthquakes were generated by TF. According to Oxcal distribution using the Bayesian methods, the time of the events lie between 46.2 ± 6.1 and 1.6 ± 0.3 ka. When the events are compared with the historical earthquakes, the last event is correlated with the earthquakes of 47 AD and/or 177/178 AD on the Doğanbey segment. Moreover, the other events can be attributed to the late Pleistocene–Holocene earthquakes that are prehistorical periods. Our results provide a recurrence interval of an earthquake along the TF to between 0.7 and 4.3 ka for the Holocene period. The elapsed time since the most recent surface faulting earthquake on the TF is 1844 years. It is suggested that it is predicted that TF has the potential to produce destructive earthquakes in the near future, especially in Orhanlı and Çatalca segments which may be considered as a seismic gap. [ABSTRACT FROM AUTHOR]

The 45-km-long, E-W to NW-SE-striking Manisa Fault Zone, which constitutes the western section of the Gediz Graben, is characterized by a pure normal sense of motion with a minor strike-slip component. Even though there are numerous historical earthquakes have been listed in Western Anatolia Graben System, a few studies have been addressed on seismic sources of the earthquakes so far. According to existing literature, the western segment of the Manisa Fault Zone is well known characterized; however, the eastern segment of it has rarely been addressed. To decipher the Holocene seismotectonic behavior of the eastern segment of Manisa Fault Zone, trench-based paleoseismological analyses for the first time were performed along with it. To constrain the timing and frequency of past earthquakes, and elapse time from the last activation using the optically stimulated luminescence (OSL) and radiocarbon (14C) dating, we collected twenty-six colluvial and paleosol samples from the trenches. The obtained paleoseismic data show that (i) Manisa Fault Zone is responsible for six surface rupturing earthquakes since late Pleistocene-Holocene, which is occurred at 30.6 ± 8.8 ka (E1), 15.0 ± 5.0 ka (E2), 6.6 ± 1.3 ka (E3), 2.9 ± 1.3 ka (E4), 0.8 ± 0.4 ka (E5), and 0.1 ± 0.1 ka (E6), (ii) the recurrences interval of destructive earthquakes on Manisa Fault Zone was found between 0.95 kyr to 3.8 kyr for Holocene, and (iii) the elapsed time since the most recent surface ruptured earthquake on the Manisa Fault Zone is 159 year. [ABSTRACT FROM AUTHOR]

In this study, the thermoluminesce (TL) properties of natural onyx were determined after β-irradiation ( 9 0 Sr/ 90 Y) at room temperature. The effect of the additive dose and variable heating rate for TL glow peaks of the sample were investigated. Computerized glow curve deconvolution (CGCD) methods were used to determine the number of peaks and kinetic parameters related to the TL glow peaks in natural onyx from Turkey. It was also determined kinetic parameters of onyx by means of the variable heating rate (VHR) method. The sample was exposed to β-irradiation between 2.4 Gy and 2.457 kGy. The CGCD methods showed that the glow curve of sample is the superposition of at least six first order components which were ascribed as P1-P6. The dose responses of some peaks have similar patterns and they follow linearity. The effect of heating rates on the response of dosimetric glow peaks of sample was studied. The maximum TL peak intensities of glow curve are decreasing with increasing heating rate and maximum TL peak intensities at 1 °C/s drops to 20% of the initial value when the sample is read at 6 °C/s. [ABSTRACT FROM AUTHOR]

Dolomite is a carbonate mineral of calcium and magnesium having the chemical formula CaMg(CO 3) 2. It is a reservoir for significant petroleum reserves and mainly used as building and ceramic material. Thermoluminescence (TL) emission of this mineral has been examined in the literature, especially collected from Egypt, India, and Brazil. In this study, the aim is to investigate TL properties of dolomite mineral which has a wide reserve in Mersin/Turkey. Structural, morphological, and elemental analyzes were performed by X-ray Diffraction (XRD) Spectroscopy, Scanning Electron Microscope equipped with Energy Dispersive X-ray Spectrometer (SEM-EDS), and Inductively Coupled Plasma Mass Spectrometer (ICP/MS), respectively. TL measurements were carried out using a TL/OSL reader with a90Sr/90Y beta source. The natural TL (NTL) curve of the sample showed two peaks at around 255 and 345 °C by the wideband blue filter whereas an additional peak at 115 °C was observed under the beta irradiation. In addition, at high doses from 50 Gy, a shoulder at around 402 °C occurred. The optimum annealing temperature and duration of the sample were determined as 500 °C and 30 min. In order to remove the low-temperature peak, a preheating process at 200 °C with 23 s duration was applied before each TL readout. TL response to absorbed dose showed good linearity over the 0.1–1200 Gy dose range and the sample was observed to be reusable with only 1.7% change up to 10 cycles under a dose of 100 Gy. The kinetic parameters (activation energy E (eV), frequency factor s (s−1), kinetic order b) of the evident glow peaks were estimated using Peak Shape (PS), Various Heating Rate (VHR), Initial Rise (IR), and Computerized Glow Curve Deconvolution (CGCD) methods. The kinetic analysis indicated that the TL glow curve of the preheated sample consists of four individual peaks having activation energies of ∼1.56, 1.60, 1.78, and 1.73 eV, and these peaks obey second and general-order kinetics. • TL character of natural dolomite mineral originating in Turkey was investigated. • TL glow curve of the β-irradiated sample exhibited three peaks at 110, 255, and 345 °C and a shoulder at 402 °C at high doses. • The sample shows a good linear TL response in the 0.1–1200 Gy β-dose range. • The sample can be reused up to 10 sequential cycles with the deviation of 1.7%. • TL kinetic analyses revealed the decomposed peaks have second- and general-order kinetics. [ABSTRACT FROM AUTHOR]