IntroductionPaleoseismology is a powerful technique to study the earthquake history and potential of active faults. Previous paleoseismology studies along normal fault systems have provided important information regarding the seismotectonic behaviour, timing, slip rates, size, and intervals of past earthquakes (

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<p>The Lake Hazar (Elazığ) is situated as an inter-mountain basin located on the East Anatolian Fault Zone (EAFZ) which is a major continental left-lateral strike-slip fault in Eastern Turkey. Since most of the major cities in the eastern part of Turkey with high populations are located along or near the EAFZ; studies focused on earthquake risk in the near-future have a significant importance of carrying in terms of socio-economic conditions. Relevant with massive earthquakes during different geologic periods due to local and regional tectonic conditions; occurred earthquakes are measured between 6.7-7.8 Mw in Lake Hazar during the last 50 years.</p><p>Therefore, Lake Hazar is considered to be archive as receiving most of the past earthquake records that are considered to be deposited as turbidites along the lake floor. For this reason, this study aims to investigate the earthquake-related turbidites (seismo-turbidites) in Lake Hazar and special interest on their sedimentological parameters. For this purpose; seven sediment cores retrieved from Lake Hazar have been examined by using multi-parameters, including mainly sedimentologic analyses together with physical and geochemical imprints. Grain size parameters of the seismoturbidites such as mean, mode, and median together with sorting and skewness reveal depositional processes during the turbidite deposition along the lake floor. According to lithologic and grain size parameters; deciphered distinct facies variations of seismoturbidites, each of them was indicated various sedimentologic processes related to different depositional dynamics. The geochemical analyses of the seismoturbidite allow us to define the deepwater condition during and after its deposition and the source of the transported sediments.</p><p>The formation of laminated seismoturbidites is characterized by the finest-grain size that was presumably formed by suspended deposition under a strong seiche effect in deep parts of the lake. The coarser seismoturbidites represent massive and graded facies that are mainly deposited by traction carpet along the lake slopes as a result of slumps triggered by the earthquakes. The high fluctuation in grain sizes of the coarser seismoturbidites also indicates the existence of seiche effect during/or after the earthquakes that may have resulted in strong grain segregation of the transported sediments from slope to the basin of the lake. This study is supported and funded by TÜBİTAK Project (Grand Number: 119Y251).</p><p> </p>

<p>Multi-spectral satellite imagery becomes a powerful tool in analyses of the earth’s surface in various aspects, including tectonic studies. There are many worldwide samples of such studies, documenting the distribution of faulting or deformation of lithological units especially in arid, semi-arid regions. The East Anatolian Shear Zone and its most prominent member, the East Anatolian Fault (EAF), is part of such a region, where the modern techniques of remote sensing can provide information on the history of this transform fault system. The EASZ and the EAF, together form the eastern boundary of the Anatolian Block, which in this study, we compare the efficiency of Advanced Space Borne Thermal Emission and Reflection Radiometer (ASTER) and Landsat-8 Operational Land Imager (OLI) images in the discrimination of lithological formations and the Pazarcik Segment of the EAF. First, we used the band combinations of 2/5/1 and 7/3/1, then 4/3-6/2-7/4 and 1/3-1/9-3/9 band ratios were independently selected in order to make an additional evaluation of the lithological discrimination for Landsat 8 OLI and ASTER T1 images, respectively. In the last stage, we used Principal Component Analysis (PCA), which provided a richer colour spectrum than the Band Combination and Band Ratio methods. The preliminary joint-analysis of these three methods allowed us to better understand the basin geometry along this part of the Pazarcik Segment. Accordingly the northern part of the Golbasi basin which hosts the Golbasi Lake, presents a rhomboidal geometry whereas the southern part is divided from the north with a wedge-shaped basin geometry. Towards southwest of the Pazarcik Segment, the Kisik River is left-laterally offset about ~4.8 km which is detectable on the band ratio images. Most critically, the image analysis highlight a geological offset along the Pazarcik Fault Segment at the Golbasi Lake side of the Hoya Formation. A left-lateral cumulative offset of ~11 km is measured along the displaced Hoya formation favouring the hypotheses of either a diachronic origin for the northern and eastern tectonic boundaries of Anatolia, among which the northern one highly exceeds the eastern boundary in terms of total slip, hence the age, or a wider shear zone where the total strain has been shared among parallel/sub-parallel segments.</p>

The sedimentary sequence in Lake Salda has been first documented in detail by analyses of high-resolution seismic profiles and sediment cores together with onshore outcrops along the present coastline of the lake. Such a multi-proxy approach provides a sensitive record of changing lake level and depositional conditions in Lake Salda during the mid-to-late Holocene. The low water level during the middle Holocene is followed by subsequent lake level decrease until 1690 cal year BP due to a drier climate. This prominent climate deterioration induced the coastal regression in the lake as inferred from the progradational deltaic sequences in the high-resolution seismic record. During the same period of a dry climate, oligotrophic lake conditions gave rise to the formation of stromatolite in the lake, timely coinciding with the Roman Warm Period. The following period of the late Holocene is represented by considerable lake level drop due to the enhanced dry climate that is earmarked by prominent erosional truncation surface and channel-incisions in the seismic profiles. This aridification phase is subsequently followed by transgressive lake level during 1690-1050 cal year BP, giving rise to a retreat of the deltaic deposit further inland as documented in the high-resolution seismic profile. The further deepening of the lake by contributions of both climate and tectonics during the last 650 cal year BP produced a transgressive unit with typical of onlapping architecture in the seismic reflection profiles and the formation of Gilbert-type fan deltas along the shoreline.