This study focuses on the morphotectonic evolution of the Kaş–Demre Karst Plateau in the Western Taurus Mountains. The data were obtained through detailed mapping of faults, lithological units, and geomorphic features. An erosional surface developed in this area under compressional tectonic regime between the Langhian and the late Pliocene. Since the late Pliocene, and particularly from the beginning of the Quaternary, an extensional tectonic regime became dominant, leading to the formation of a series of horst–graben structures. During this period, while the region continued to undergo tectonic uplift, the antecedent Demre Stream began downcutting into the plateau. At the same time, cascade-type poljes developed within graben structures, and consequently, some section of the early Pliocene valleys were transformed into wind gaps on the horsts. The floors of the two youngest poljes located to the south of the cascade system subsided due to vertical displacement along the bounding faults, and therefore became submerged under the waters of Kekova and Kaleüçağız bays as a result of Holocene transgression. Submerged archaeological remains belonging to the ancient city of Dolchiste in Kekova Bay, together with a corrosional surface identified at a depth of −131 m within the Kekova polje, provide clear evidence for relative sea-level changes. The sediments (22 m thick) deposited on this corrosional surface indicate that the polje was submerged during the Last Interglacial Period and regained its polje characteristics during the Last Glacial Period.

The study area is located near the apex of the north-facing and V-shaped Konya-Niğde Graben. Its south-southeast margin is defined and controlled by the NE-trending Karaman-Niğde Fault Zone. It also forms the geographic boundary between the central Tauride in the south and central Anatolia in the north. This study aimed to determine the Latest Pliocene–Quaternary uplift rate of the central Tauride and the evolutionary history of the Kızıllar Canyon located on the uplifting southern footwall block of the Karaman Niğde Fault Zone. Both the geological and geomorphological field data, which were obtained within the framework of this study, revealed the following: (1) the Kızıllar River drainage system developed as a result of several capture events; (2) Lithological and hydrological characteristics of the valley reveal the reason for the lack of gradation in the river's longitudinal profile; (3) the Kızıllar Canyon reflects the incision process of the Kızıllar River; (4) the Kızıllar River cut vertically into its bed up to 230 m, which corresponds to the minimum Latest Pliocene–Quaternary uplift rate of the central Tauride (~0.06 mm/yr); and (5) the Kızıllar Canyon developed as a natural response of the river to the uplift of the Konya-Niğde Fault Zone footwall block.

As a result of the interaction between the Anatolian Plate and the African Plate to the south, and the Aegean microplate to the west, a complex extensional regime has developed across Western Anatolia. This dynamic tectonic framework causes significant crustal deformation and temporal strain accumulation, particularly along the active Fethiye–Burdur and Gökova fault zones. The Aegean region is considered one of the most seismically active areas worldwide. The Mw 6.7 earthquake that occurred within the Gulf of Gökova on 21 July 2017 represents one of the most recent destructive earthquakes in the region. Despite the pronounced seismic activity in this area, no active fault zones are mapped in this section of the Turkish Active Fault Map. The absence of mapped active structures has highlighted the necessity of detailed investigations into the region’s present-day tectonic deformation characteristics. Within the scope of this study, the aim is to determine crustal deformation and temporal strain accumulation based on Global Navigation Satellite System (GNSS) observations. For this purpose, the region has been monitored since 2021 through campaign-based GNSS measurements and data obtained from continuously operating GNSS stations.In the study, GNSS data has been collected from 6 CORS-TR (Turkey National Permanent GNSS Network- Active) stations, 7 Turkey National Fundamental GNSS Network (TNFGN) sites, and 16 campaign GNSS sites. Four GNSS campaign measurements were carried out between 2021 and 2024 .The GNSS data were processed to generate coordinate time series and estimate station velocities using with Bernese GNSS Software version 5.4. Based on these results, a statistically significant velocity field was identified across the region, with horizontal southwest-directed velocities ranging from a maximum of 41.67 ± 1.76 mm/yr to a minimum of 22.05 ± 2.95 mm/yr. Also, temporal strain accumulation in the region was computed using a finite element method . The results indicate that the eastern and western parts of the region are characterized by different strain fields, and that the amount of strain has increased and expanded spatially over the observations.This work is supported by TUBITAK CAYDAG Project Number 121Y3

Determining why earthquake ruptures stop is a central challenge in earthquake science and seismic hazard assessment. The P & uuml;t & uuml;rge segment of the East Anatolian Fault Zone, T & uuml;rkiye, exhibits shallow creep ( 6.5 earthquake ruptures at greater depth. Here, we evaluate whether variations in frictional stability along this segment aided arrest of the 2020 M 6.7 Elazi & gbreve; and 2023 M 7.8 Pazarc & imath;k earthquake ruptures. Analysis of Sentinel-1 Synthetic Aperture Radar imagery indicates the 2023 M 7.8 rupture propagated laterally into a metamorphic massif within the P & uuml;t & uuml;rge segment, where slip rapidly decayed below detection limits. Creepmeters along this segment recorded no significant surface afterslip (<3 mm) in the following year. To investigate this fault-slip behavior, we conducted triaxial friction experiments on P & uuml;t & uuml;rge fault gouge sampled from an outcrop exposure. The gouge, composed primarily of muscovite, quartz, and calcite, is velocity strengthening at conditions approximating 0-2.5 km depth and velocity weakening at 4-5 km depth. This transition to velocity-weakening friction is associated with enhanced comminution and shear localization observed microstructurally. Our results suggest that depth-dependent frictional stability of the P & uuml;t & uuml;rge fault segment facilitates rupture nucleation and propagation at depth while maintaining rupture-arresting behavior near Earth's surface.

Recent studies have shown that large earthquakes can induce deformation at distances significantly greater than those predicted by simple elastic half-space models. This observation indicates that regional-scale effects must be considered when assessing post-earthquake deformation and seismic hazard. Several studies have demonstrated that the 6 February 2023 Kahramanmaraş earthquake doublet (Mw 7.8 and Mw 7.6) affected distant regions in addition to the immediately ruptured faults.Within the scope of our project, supported by TÜBİTAK 1001 (Project No. 123Y350), we investigate the current fault activity and seismic hazard of fault segments located north of the 2020 Mw 6.8 Sivrice earthquake and the 2023 Mw 7.8–7.6 Kahramanmaraş earthquakes. Our approach integrates multidisciplinary datasets, including seismology, geodesy (GNSS, InSAR, and creepmeters), and geology (morphometric analyses). The study area comprises the East Anatolian Fault (EAF)–Palu segment, the North Anatolian Fault (NAF)–Yedisu segment, and the Karlıova Triple Junction (KTJ).Following the 2020 Mw 6.8 Sivrice earthquake, seismicity increased along several sections of the EAF. Initially, aftershocks were concentrated within the rupture zone and subsequently migrated southwestward, while no significant increase in seismicity was observed along the Palu segment to the north. Approximately three years later, the Kahramanmaraş earthquake sequence (Mw 7.8 and Mw 7.6) occurred on 6 February 2023, after which seismic activity expanded over a broad region along the EAF. Compared to the ruptured areas and their immediate surroundings, seismicity remained relatively sparse along the northern sections of the EAF, where our study area is located.The Palu segment lies adjacent to the NE the Sivrice earthquake rupture zone and forms part of the EAF, whereas the Yedisu segment, located on the NAF, is characterized by a long-term slip deficit and is considered a seismic gap. The Karlıova Triple Junction represents the intersection of the North and East Anatolian faults and exhibits a complex faulting system resulting from active continental collision. Each of these fault segments displays distinct kinematic characteristics and has been affected by the 2020 and 2023 earthquakes to varying degrees.The current seismicity distribution within the study area (Palu, Yedisu, and KTJ) indicates that earthquake clusters observed prior to these large events remain active, with no anomalous seismic behavior identified to date. Despite the relatively low level of seismicity along the Palu segment compared to the main rupture zones, geodetic observations suggest that its well-known creep velocity has accelerated following the 2020 and 2023 earthquakes. In addition, we investigate the relationship between long-term and present-day geodetic deformation rates, morphological indicators, and slip deficits along active fault branches using continuous and campaign GNSS measurements together with InSAR data. These multidisciplinary datasets, currently under preparation, will be integrated intofault interaction modeling and seismic hazard assessments for the region at the conclusion of the project.

The effect of Global Navigation Satellite System (GNSS)-based tropospheric corrections on Interferometric Synthetic Aperture Radar (InSAR)-derived surface deformation estimates was evaluated for the 24 January 2020 Mw 6.8 Elazığ–Sivrice earthquake. Tropospheric delay is a major source of error in InSAR processing and may affect the interpretation of earthquake-induced deformation fields. To assess this effect, ascending and descending Sentinel-1A images were processed using the Sentinel Application Platform (SNAP) within a standard Differential InSAR (DInSAR) workflow. Phase filtering was applied to reduce noise, and phase unwrapping was performed using the Statistical-Cost, Network-Flow Algorithm for Phase Unwrapping (SNAPHU). Tropospheric delays estimated from GNSS observations were applied to the interferometric displacement products and compared with corrections from the Generic Atmospheric Correction Online Service for InSAR (GACOS). The results show that both GNSS- and GACOS-based corrections influence the spatial distribution of line-of-sight (LOS) displacement fields. However, their effects are not spatially uniform across the study area. Local discrepancies between the corrected products are likely related to regional atmospheric variability, topography, acquisition geometry, and the distribution of GNSS stations. Neither correction strategy produced a spatially uniform improvement across all interferometric pairs; instead, the results highlight the need to carefully evaluate atmospheric correction performance using spatial statistics, profile comparisons, and displacement-difference analyses. This study demonstrates that GNSS- and GACOS-based corrections do not uniformly improve displacement products but provide complementary information for identifying atmospheric contributions and assessing uncertainty in InSAR-derived earthquake deformation fields.

The aim of this study is to determine the vertical land motion (VLM) and horizontal land motion (HLM) at the tide gauge stations located along the coast of the Black Sea using ground-based (GNSS and tide gauge) and satellite-based (satellite altimetry and InSAR) data. In this context, the tide gauge data were initially obtained from the Turkish Sea Level Monitoring System (TUDES) and Permanent Service for Mean Sea Level (PSMSL) data archive. The XTRACK data set, adopting the coastal altimetry approach, was selected as the satellite altimetry data, and sea level data from both methods were subjected to the Least Squares Parameter Estimation to determine sea level trends. The trends in sea level during the time period of 1993-2022 have been estimated based on the installation dates of tide gauge stations, using data from both tide gauge stations and satellite altimetry. In the analyses based on sea level data, subsidence trends were determined between the years 1993-2022 at the AMSR, TRAB, and POTI tide gauge stations, while an uplifting trend in VLM was observed at the other stations. These values were compared with the results obtained from GNSS observations at the tide gauge stations using the GAMIT/GLOBK software, yielding consistent outcomes. Furthermore, through the evaluation of GNSS data, the HLM at all tide gauge stations in the Black Sea region was estimated to be 1.4 +/- 1.7 mm/yr in the northeast direction (approximately 63 degrees).Additionally, a regional sea level trend map was generated using XTRACK satellite altimetry data from 1993 to 2022, revealing a sea level rise trend of 1.3 +/- 0.6 mm/yr in the Black Sea.

Bu araştırmanın temel amacı, jeodezik ağlarda farklı matematiksel modellerin kullanımının dengeleme sonuçları üzerindeki etkilerini incelemektir. Bu kapsamda, 13 noktalı, doğrultu ve kenar ölçüleri gerçekleştirilmiş bir yatay kontrol ağı kullanılmıştır. Analizlerde, kenar-doğrultu, yalnızca doğrultu ve yalnızca kenar ölçüleri olmak üzere üç farklı ölçü grubu tanımlanmış ve serbest ile dayalı ağ dengeleme yöntemleriyle değerlendirilmiştir. Çalışmanın bulguları, tüm ölçü grupları için fazla ölçü paylarını, ölçülerde tespit edilebilen hata sınır değerlerini, belirlenemeyen kaba hataların diğer ölçüler üzerindeki etkisini ve nokta konum hatalarıyla hata ve güven elipslerini kapsamlı bir şekilde ortaya koymuştur. Elde edilen sonuçlar, jeodezik ağların güvenilirliğinin belirlenmesinde matematiksel (fonksiyonel ve stokastik) model seçiminin kritik bir faktör olduğunu ortaya koymaktadır.

We report triggered slip and afterslip following the Mw7.8 and Mw7.6 Kahramanmaraş, Türkiye earthquakes of 6 Feb 2023, as recorded by 13 carbon-rod extensometers installed across surface faults. These extensometers measure 6–54 m long and were installed at 30° to the fault with a resolution of 2 µm and range of 1.5 m. Three creepmeters were operating at the time of these earthquakes: two on the North Anatolian fault near Ismetpasa and a third on the East Anatolian fault near Sivrice. The earthquakes induced 5 mm of triggered slip at Ismetpasa, but only 1 mm of slip on the East Anatolian Fault at Sivrice. Both of these triggered slip events corresponded in amplitude to the release a local creep slip-deficit that had developed prior to the earthquakes. Seven afterslip meters installed along the central segments of the primary ruptures recorded negligible afterslip (<3 mm in 6 months) revealing that the fault in these locations was now locked. The remaining three instruments, at the northwestern and southeastern extremities of the mainshock ruptures revealed significant afterslip. At Goksun near the northwestern end of the Mw 7.6 rupture we recorded surface slip preceding local aftershocks, including a unique record of accelerating slip preceding a local Mw4.7 aftershock. A second region of continued slip occurs at the eastern end of the Mw 7.8 rupture known as the Puturge gap, a segment of the fault that also arrested coseismic slip in the Elazığ-Sivrice 2020 Mw 6.8 earthquake. The initial array of five extensometers here was supplemented by a further two. They reveal that > 3.8 mm/yr of slip continues at depth. In September, three creepmeters here, over a distance of 45 km, recorded what appears to be an eastward propagating creep event in the subsurface. To investigate the evolution of subsurface slip further in the Puturge gap the five creepmeters have been supplemented with a 3-component 1-km-scale cGPS array recording at 5 Hz.

In this study, the effect of model management on performance is analysed by comparing the performance of station-based models and the single model trained with all station data using the Long Short Term Memory (LSTM) and Gated Recurrent Unit (GRU) deep learning algorithms for the North, East and Vertical components of GNSS station data. For Scenario I, where separate models are used for each GNSS station, and Scenario II, where a single combined model is used with aggregated data, model performance is evaluated for the East, North and Vertical components using Root Mean Square Error (RMSE), Mean Absolute Error (MAE) and Coefficient of Determination (R-2). With the GRU algorithm, the average RMSE for the East component is 1.68 and 1.67 mm and the MAE is 1.24 and 1.27 mm for scenarios I and II respectively; for the North component the RMSE is 1.70 and 1.72 and the MAE is 1.32 and 1.33 mm; for the Vertical component the RMSE is 4.50 and 4.43 mm and the MAE is 3.58 and 3.50 mm. The results show that the single model approach can simplify model management and achieve comparable accuracy to separately trained models, especially in regions with more homogeneous data characteristics.

This study examines long-term sea level changes and their relationship with meteorological parameters at the Antalya, Bodrum, Erdek, and Mentes,tide gauge (TG) stations along the Mediterranean, Aegean, and Marmara coasts of T & uuml;rkiye between 1985 and 2024. Sea level trends were compared using both local TG data (TUDES) and satellite altimetry data from the Copernicus Marine Service (CMEMS). Trends in meteorological parameters were evaluated using parametric (least squares linear model) and non-parametric (Mann-Kendall trend test and Sen's Slope method) statistical analyses. The results indicate that the regional sea level rise rate for the period 1993-2024 was estimated at 3.3 +/- 1.0 mm/yr based on TG data and 3.8 +/- 0.7 mm/yr based on CMEMS data. Significant increases were observed in sea water temperature (0.035-0.051 degrees C/year) and air temperature (0.037-0.060 degrees C/year), while a statistically significant increase in water vapor pressure was only observed in Bodrum. Decreases were detected in atmospheric pressure and relative humidity; however, only the decline in relative humidity at Antalya was statistically significant. Autocorrelation analysis revealed periodic trends in sea level and meteorological observations, and cross-correlation analysis identified the lagged influence of thermal expansion and atmospheric pressure variations on sea level changes. This research is novel in employing the longest observational record for T & uuml;rkiye's coastal regions, combining in-situ and satellite-based data to provide timely insights into the coastal impacts of climate change.

Batı Toroslar’da, Göller Yöresi’nde yer alan göllerin bir kısmı tektono-karstik kökenli çukurluklar içerisinde oluşmuştur. Bu göllerin en büyüklerinden biri de Eğirdir Gölü’dür. Bu gölde son yıllarda meydana gelen seviye alçalması dikkat çekici boyutlara ulaşmıştır. Şimdiye kadar yapılan çalışmalarda da gölün batı kıyısında yer alan düdenler dikkati çekmemiş veya önemli ölçüde göz ardı edilmiştir. Bu çalışma ise Eğirdir Gölü’nün batı kıyısında 2024 yılı Eylül ayında ortaya çıkan Süpürge düdeninin jeomorfolojik-hidrolojik özelliklerini ortaya koymak ve Eğirdir Gölü çanağının göl suları altında kalmış eski bir polye olup olmadığını tartışmak amacıyla yapılmıştır. Tartışmada Göller Yöresi’ndeki polyelerin önemli bir kısmı da ele alınmıştır. Saha çalışmasına ek olarak, uydu ve drone görüntülerinden de faydalanılmıştır. Eğirdir Gölü’nün batı kenarında kireçtaşında gelişmiş yeraltı karst sistemleriyle ilişkili olarak gelişmiş olan düdenlerin faylar üzerinde sıralandığı belirlenmiştir. Göl seviyesinin alçalması sonucunda suların kıyıdaki göl çamurları içerisinde kaybolduğu Süpürge düdenin de bunlardan biri olduğu görülmüştür. Göl çanağının ise eski bir neotektonik-taban seviyesi polyesi olabileceği sonucuna varılmıştır.

In 1999, The North Anatolian Fault (NAF) generated two destructive earthquakes, namely, the Mw 7.4 Izmit earthquake and the Mw 7.1 Düzce earthquake, in the western part of Türkiye and broke more than 180 km of NAF. After 22 years of silence, at the overlapping section of these ruptures, the region produced two earthquakes: one with a magnitude of 5 and another, a year later, with a magnitude of 5.9. In this study, we aim to examine the role of these recent earthquakes in terms of slip deficit between two ruptures.Our primary focus is on the Düzce earthquake (Mw 5.9) that occurred on 23 November 2022. Here we use a novel method to reconstruct the coseismic deformation field by enhancing the signal-to-noise ratio (SNR) from ~3 years of Interferometric Synthetic Aperture Radar (InSAR) Sentinel-1 TOPS data spanning the earthquake. We estimate a coseismic surface displacement of ~2 cm for this event.Furthermore, data from the stations belonging to the Turkish National GNSS Network and data from eight new cGPS sites that we have established in the area have been processed to observe coseismic and postseismic displacement. Postseismic deformations are estimated for one month interval after the earthquake, maximum postseismic deformation is observed on the site named AKSU: 18.6 ± 2.18 mm at east and -1.5 ± 2.28 mm at north direction.A joint inversion model was developed using the aforementioned geodetic and seismological data to estimate the region's final state and was linked to the potential slip deficit of previous major earthquakes in 1999.

This study explores the impact of the selected GNSS reference station numbers on determining horizontal and vertical coseismic deformations resulting from the October 23, 2011, Mw 7.1 Van Earthquake in Eastern Anatolia, near Van city center. Leveraging high-precision Global Navigation Satellite System (GNSS) measurements from 14 CORS-TR (Continuously Operating Reference Stations of T & uuml;rkiye) stations and utilizing Bernese v5.2 software for data analysis, the research evaluates the effect of datum selection through various reference station configurations on the accuracy of coseismic displacement measurements. Our findings indicate significant variations in RMS values and coseismic displacements across different datum models. The analysis shows that models incorporating eight or more International GNSS Service (IGS) stations in the datum definition yield more stable and consistent results, with variations in displacement measurements not statistically significant when compared to a model using all available (19 station) IGS stations. This underscores the critical importance of datum definition in geodetic measurements for the assessment of natural disasters and emphasizes the need for a comprehensive and precise selection of reference stations number in the geodetic field. The study contributes to the broader geodetic efforts to develop fault slip models and improve the understanding of seismic events' impact on Earth's surface.

The presented study aims to monitor a potential hydrological drought in Lake & Idot;znik, one of the largest freshwater lakes in T & uuml;rkiye, located in the NW region of the country. In this context, in-situ and satellite altimetry-based water level data, meteorological data such as temperature and precipitation, and high-resolution multispectral satellite images from 2015 to 2024 have been utilized. A linear model was fitted to the water level data acquired from Turkish Directorate General for State Hydraulic Works and the altimetry-based data from HydroWeb data archive, which estimated a decreasing trend of-22.9 +/- 0.6 cm and-22.6 +/- 0.6 cm in lake water levels, respectively. The Mann-Kendall/Sen's slope trend analysis was performed on the series of temperature and precipitation data obtained from Turkish General Directorate of Meteorology, showing that there is a 0.049 degrees C increase in temperature and an annual-0.80 mm decrease in precipitation. According to the calculated temperature and precipitation values, which are increasingly high and low respectively, the hydrological drought indicators SPI and SPEI were determined to be showing an increasingly severe hydrological drought in this region. It then analyzed Sentinel-2 satellite imagery between 2015 and 2024 to determine the water surface area of the lakes with NDWI. According to Sentinel-2 images, the lake water surface area in 2023 went down by 2.7 km2 compared with that in 2015. These findings bring forth crucial implications for regional water resource management and ecosystem sustainability, placing significant emphasis on proactive measures that should be considered in order to mitigate the long-term impacts of hydrological drought in Lake & Idot;znik and its surroundings.

Active faults release part of the elastic strain energy stored in the crust via aseismic slip, either through slow slip events (SSEs) or steady slowly creep. However, spatial and temporal interactions between these different styles of aseismic slip have yet to be quantified especially at depth. Along the central section of the North Anatolian Fault, we apply a Multichannel Singular Spectrum Analysis (MSSA) on GNSS time series of ground motion to detect a 4.8 0.08 shallow SSE (2–5 km depth) lasting for 26 5 days, in agreement with local creepmeter observations. Our observations confirm the recurrence of SSEs next to a steadily creeping section of the fault. Finally, we discuss how steady creep and SSEs interact spatially and temporally along the fault segment.

Geodetic GNSS (Global Navigation Satellite Systems) measurement systems play a crucial role in studies aimed at monitoring crustal movements. From the past to the present, GNSS measurement systems have served as active measurement tools within the scope of these studies. In these studies, geodetic GNSS measurement systems can be used as continuous reference stations and are primarily employed in campaign-type measurements. However, the setup and operation of continuous reference stations require a significantly high financial budget. On the other hand, campaign-type measurements necessitate simultaneous data collection using multiple GNSS measurement systems, depending on criteria such as the size of the field and the number of points. This, in turn, increases the overall measurement costs. Today, due to the high expenses associated with geodetic GNSS measurement systems, research is being conducted on the use of low-cost GNSS systems in structural health monitoring, displacement determination, and other applications. Since the studies conducted so far have generally been limited to short-term observations at short baselines, there remain questions about the performance of low-cost GNSS measurement systems in monitoring crustal movements. In this study, the objective is to determine the performance of GNSS measurement systems, whose unit costs are considerably lower compared to geodetic GNSS systems, in monitoring crustal movements. For this purpose, two low-cost GNSS measurement systems will be deployed on the northeastern edge of the surface rupture caused by the earthquakes of Mw7.8 and Mw7.6 that occurred in Kahramanmaraş on 06.02.2023. This will enable the continuous monitoring of the post-earthquake effects in the Çelikhan segment on the East Anatolian Fault (DAF). Furthermore, the performance of low-cost GNSS measurement systems will be assessed. In addition to the measurements taken at permanent stations, campaign-type GNSS measurements will be conducted at four different points using both geodetic and two low-cost GNSS measurement systems throughout the project. By processing the data obtained from geodetic GNSS measurement systems and the data acquired from low-cost GNSS measurement systems in the same region, the results will be analyzed. This analysis aims to determine the performance of low-cost systems in monitoring tectonic structures through continuous measurements and campaign-type measurements. This is work is supported by TUBITAK project number 123Y147.

The increasing availability and affordability of low-cost Global Navigation Satellite System (GNSS) systems have made them a viable alternative for various geospatial applications. However, their performance and positioning accuracy require rigorous evaluation, especially when compared to geodetic-grade GNSS systems. This study investigates the accuracy of low-cost GNSS systems in positioning by comparing their results with those obtained from high-precision geodetic GNSS systems.To evaluate the performance of low-cost GNSS systems, campaign type GNSS measurements were conducted at four points using both low-cost and geodetic GNSS systems. The collected data were processed using the Canadian Spatial Reference System Precise Point Positioning (CSRS-PPP) and the AUSPOS relative positioning services. The positioning results from these services were analyzed to assess the performance of low-cost GNSS systems relative to their geodetic counterparts. Preliminary findings indicate that low-cost GNSS systems exhibit promising accuracy levels in comparison to geodetic systems. The results highlight the potential and limitations of low-cost GNSS technology for scientific and practical applications.This study contributes to the growing body of knowledge on low-cost GNSS technologies and provides insights into their applicability in fields such as tectonic monitoring and geodetic research. Future work will focus on refining processing techniques to further enhance the reliability of low-cost GNSS systems.

Türkiye's geographic position between Europe, Asia, and Africa gives it pivotal importance for understanding the local, interregional, and intercontinental dynamics of Neogene vertebrate evolution. Although rich in vertebrate fossil deposits spanning the Middle and Late Miocene, associated geochronology has been limited by the lack of available volcanic materials that allow radioisotopic dating and geochemical correlation. As a result, calibrating mammalian evolution has been largely restricted to the semicircular application of paleomagnetic inferences combined with temporally ill-constrained and geographically remote biochronological deductions. For example, fossils from three Greek localities and one Anatolian locality assigned to the primate genus Ouranopithecus lack datable samples, leaving its ages poorly constrained. Chronological calibration based on the 40Ar/39Ar results reported here demonstrates how a fauna-focused, precision geochronology can enhance a better understanding of evolving species lineages and the ecosystems they comprise.