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This paper deals with the use of satellite Quick- Bird images to find traces of past human activity in the ancient territory of Hierapolis (Turkey). This is one of the most important archaeological sites in Turkey, and in 1988 it was inscribed in the UNESCO World Heritage list. Although over the years the archaeological site of Hierapolis has been excavated, restored and well documented, up to now the territory around the ancient urban area is still largely unknown. The current research project, still in progress, aims to search the area neighbouring Hierapolis believed to have been under the control of the city for a long time and, therefore, expected to be very rich in archaeological evidence. In order to investigate a large area around the ancient Hierapolis and discover potential archaeological remains, QuickBird images were adopted. Results from satellite-based analysis allowed us to find several unknown rural settlements dating back to early Imperial Roman and the Byzantine age. Two significant test sites were focused on in this paper in order to characterize the different spectral responses observed for different types of archaeological features (shadow and soil marks). Principal Component Analysis and spectral indices were computed to enhance archaeological marks and make identification easier. The capability of the QuickBird data set (panchromatic, multispectral channel, PCA and spectral indices) in searching for archaeological marks was assessed in a quantitative way by using a specific indicator. [ABSTRACT FROM AUTHOR]

This paper presents one of the most comprehensive tests conducted about the real-time kinematics (RTK) and continuously operating reference stations (CORS) network using instruments from three global positioning system (GPS) manufacturers (Leica, Topcon, and Trimble). The test was carried out between August and October 2006 in the Marmara Region of Turkey as part of the research project for establishing RTK CORS network covering all of Turkey. Three GPS networks (NET-120, NET-90, and NET-60) were designed, each consisting of six CORS points: with interstation distances of 120, 90, and 60 km, respectively. Leica, Trimble, and Topcon directly participated in the tests, each company contributing a 2 week effort. RTK surveys were compiled at check points (previously known points) and new points were generally selected in built-up areas. Flachen Korrectur parameter—Spatial correction parameters, virtual reference stations, pseudoreference stations, and master auxiliary concept techniques were used for RTK positioning. Postprocessing by network solution software was also used at check points. The results of network-based RTK and postprocessing were found to be successful at each net, the main exception being the difficulties encountered by one of the firms participating at NET-120. Results are discussed in the paper. [ABSTRACT FROM AUTHOR]

An evapotranspiration method comparison was carried out by the International Water Management Institute (IWMI, Sri Lanka), at two locations in the Gediz Basin, Turkey, in the period from May to September 1998. In the IWMI study a number of ground-based techniques were compared with results obtained by remote sensing methods. Recently, a search of the satellite active archive yielded over 70 high quality level 1b images from NOAA/AVHRR over the same time period. The processing of these images with the SEBAL algorithm enabled us to build up a detailed time series of sensible and latent heat fluxes for a period of 120 days. In this paper a comparison is made between the sensible and latent heat fluxes determined from the present series of NOAA-14/AVHRR images and the results obtained earlier from various other prediction methods applied during the 1998 IWMI project. Specifically, the NOAA/SEBAL results are assessed against the scintillometer and temperature fluctuation methods. The results show that the NOAA derived evapotranspiration values follow the seasonal irrigation cycle quite well and correspond closely to the Landsat derived values, although they are lower than the results obtained with the traditional crop factor and Penman–Monteith methods. [ABSTRACT FROM AUTHOR]

As the number of Earth geopotential models (EGM) grows with the increasing number of data collected by dedicated satellite gravity missions, CHAMP, GRACE and GOCE, measuring the differences among the models and monitoring the improvements in gravity field recovery are required. This study assesses the performance of recent EGMs derived from CHAMP, GRACE, and other data in comparison to the earlier two models in Turkish territory. Also the improvement capacities of these EGMs using local terrestrial data are inspected with two different approaches. In the first approach, the spherical harmonic coefficients of EGMs are modified depending on the local gravity data. In the second part, the original EGMs with their maximum harmonic expansions are employed in Remove Compute Restore algorithm for high resolution local geoid modelling. The assessment results with the local terrestrial data exhibited large disagreements among the models in Turkey. The outputs from regional improvements of EGMs using the gravity observations clarified the important role of the ground truth data contribution in geopotential models. The validations of the computed high resolution geoids rely on the EGMs at the GNSS/levelling networks, having 451 and 309 benchmarks, provided an absolute accuracy by means of standard deviations of the geoid height differences around 20 cm. These results from the final stage of the case study provide a comparison among the EGMs by means of their fit to the local gravity field. [ABSTRACT FROM AUTHOR]

Space-time TIR anomalies, observed from months to weeks before earthquake occurrence, have been suggested by several authors as pre-seismic signals. Up to now, such a claimed connection of TIR emission with seismic activity has been considered with some caution by scientific community mainly for the insufficiency of the validation data-sets and the scarce importance attached by those authors to other causes (e.g. meteorological) that, rather than seismic activity, could be responsible for the observed TIR signal fluctuations. A robust satellite data analysis technique (RAT) has been recently proposed which, thanks to a well-founded definition of TIR anomaly, seems to be able to identify anomalous spacetime TIR signal transients even in very variable observational (satellite view angle, land topography and coverage, etc.) and natural (e.g. meteorological) conditions. Its possible application to satellite TIR surveys in seismically active regions has been already tested in the case of several earthquakes (Irpinia: 23 November 1980, Athens: 7 September 1999, Izmit: 17 August 1999) of magnitude higher than 5.5 by using a validation/confutation approach, devoted to verify the presence/absence of anomalous spacetime TIR transients in the presence/absence of seismic activity. In these cases, a magnitude threshold (generally M <5) was arbitrarily chosen in order to identify seismically unperturbed periods for confutation purposes. In this work, 9 medium-low magnitude (4 < Mb <5.5) earthquakes which occurred in Greece and Turkey have been analyzed in order to verify if, even in these cases, anomalous TIR transients can be observed. The analysis, which was performed using 8 years of Meteosat TIR observations, demonstrated that anomalous TIR transients can be observed even in the presence of medium-low magnitude earthquakes (4b < 5.5). As far as the research (just started) of possible correlation among TIR anomalies and earthquake occurrence is concerned, such a result suggests that: a) in order to identify seismically unperturbed periods for confutation purposes, a magnitude threshold (at least) lower than 4 should be used; b) the proposed validation/confutation approach should be applied in low-seismicity areas in order to find suitably long seismically quiescent periods. [ABSTRACT FROM AUTHOR]

We use the strong motion data recorded at near-fault accelerometers combined with Global Positioning System (GPS) measurements to infer the space and time evolution of the1999 November 12 Düzce (Turkey) earthquake. We confirm that the rupture is subshear towards the west whereas it overpassed the shear speed towards the east. The mechanism of the earthquake is predominantly right lateral on a 65° north-dipping fault. The strike-slip we infer represents at least 75% of the total seismic moment. We stress that the use of strong motion data allows us to constrain a strong spatial variation of the slip direction during faulting: to the west of the hypocentral region, the slip is oblique accompanied by a significant normal component. In the central and eastern part of the activated fault the slip is almost pure right lateral. This result is consistent both with the surface offset observations and with the long-term morphology of the fault. Neither strong motion data nor GPS data can resolve the complexity of the eastern termination of the Düzce rupture. [ABSTRACT FROM AUTHOR]

Mining activities are important for the country's economy, but they cause serious threats to the environment. The geology of SW Turkey comprises Southern (Çine) Submassif of Menderes Metamorphic Massif and the Lycian Nappes. These geological units are unconformably overlain by lignite-bearing Miocene deposits, Upper Miocene–Pliocene conglomerates and Quaternary alluvial deposits. The aim of this study is to determine the geospatial change of mining activities in the Muğla-Aydın provinces, SW Turkey. For this purpose, Landsat-5 TM, Landsat-7 ETM, Landsat-8 OLI and Google Earth satellite image data for 1984, 1994, 2004, 2014 and 2018 have been used for change detection analysis. In 1984, only a Miocene lignite quarry was excavated. Then, in 1994, operations for the excavation of feldspar–quartz and marble quarries were started, and from 2004 to 2014, mining activities significantly accelerated. An aerial image of 2018 shows that an area of about 3800 ha has been exploited by mining at 149 quarries. Considering access roads to quarries, plants and dam reservoirs, the human impact extends over 3800 ha. The study area is home to several archaeological sites and endemic biota. Thus, there is an urgent need for the relocation and protection of archaeological heritages and endemic biota by creating special zones. Additionally, the rich geomorphologic features in the study area that require millions of years to form are at risk of totally disappearing. [ABSTRACT FROM AUTHOR]