Türkiye Jeoloji Bülteni

Abstract: Beachrocks, which rapidly form along intertidal zones by early carbonate cementation, can be used inHolocene sea level change and neotectonic studies, as their formation requires vertical stabilization ofthe shoreline. In this paper, three generations of beachrocks at different depths between Finike and theSyrian border are 14C dated and a mid-Holocene to recent sea level change history is tentativelyproposed.The beachrocks and raised shorelines in the study area are geographically subdivided in fiveareas: I) The westernmost beachrock in Finike Bay and Roman ruins of Andriake and Batıkşehir whichare found submerged -1.5 m to - 4 m below after post-Roman earthquakes. II) Three beachrocks levelsobserved between Finike-Antalya and Çimtur, the uppermost beachrock indicating sea levelstabilization at c. AD 400-700. III) Between İncekum and Karataş-Osmaniye Fault Zone wherebeachrocks above sea level are also observed. In İncekum surf benches between 0.5 m and 1.2 m werepreviously dated as 1815 BP to 1545 BP. IV) The southern and northern part of İskenderun Bay limitsthis area. Two generations of beachrocks, corresponding to two fossil intertidal zones are distinguishedhere: the first between 0.3 m and -0.8 m (c. AD 400-700) and the second between -0.7 m and -1.7 m. V)No beachrocks are present along the Levant coast of Turkey. However two erosional notches were previously dated as 2500 ± 100 BP (2.9 m) and c. AD 500-600 (0.8 m). A possible third notch at 1.4 m isundated.Four relative sea level stands are recognized in the study area: 1) The earliest sea level (?midHolocene) is represented by beachrocks at -3 m (±0.5 m). 2) The second stabilization of the sea leveloccurred c. AD 500-700 and is represented by beachrocks at -2 m (±0.5 m). The raised shorelinerepresented by an erosional notch at 2 m and 3 m near Samandağ (Area V) also belongs to this period.3) The third stabilization of sea level and the formation of beachrocks at -0.4 m (±0.5 m) as in Kemer(Area II) and Gözcüler (Area IV) date back to c. AD 400-600. Several Roman ruins (Area I) and a notchat 0.8 m (Area V) are known to have been raised to their present positions between c. AD 400-600. Thebench at 0.5 m (Area III) is known to have developed around AD 200-600. 4) The sea level reached itspresent position at the latest after the Selchukid era (c. AD 1200) and most probably after the EarlyByzantine period (c. AD 400-700). Our data indicate that the major causes of sea level changesobserved along the Turkish Mediterranean coast during the last 5000 years can be attributed to localtectonics rather than to climate and/or glacio-eustacy.

Abstract: Thermal hot waters are known in the terrestrial areas in the vicinity of Gülbahçe Bay. The main targetof this study is to examine the presence of these hot water sources. A high-resolution shallow seismicstudy (3.5 kHz) was used to determine the high potential hydrothermal area in Gülbahçe Bay andsediment samples were collected by gravity corer at 14 points for palynological analysis. Thepalynological findings obtained from these core samples were confronted with a "Reference sample",which came from outside the study area and is thought to be able to change with the thermal features ofenvironment. . Concerning the seismic profiles obtained from Gülbahçe Bay, it has been suggested that the highson the sea bottom were formed from clustered corals, and this has been observed to be common in hotwater conditions. In the bay these highs cover an area of approcimately 16km². The palynologicalresults obtained from the sediment samples in Gülbahçe Bay determined terrestrial and marinepaleoenvironmental conditions for the Late Holocene period. High palaeotopographic and lowlandareas surrounding the Gülbahçe Bay are covered by Pinus, Castanea, Quercus and Oleaeceae, Ulmus,and Cyrillaceae. Nyssa, Taxodiaceae and Cupressaceae are grown in the narrow areas of freshwatermarsh, and between these areas there are constricted open vegetation areas which are characterized byAsteraceae, Cichorioideae, Greniaceae, Artemisia, Ephedraceae and Chenopodiaceae. Due to the rarepresence of the some dinoflagellat cyst (Lingulodinium machaerophorum, Cymatiosphaera globulosa,Spiniferites ramosus and Spiniferites spp.), the Late Holocene period dating is supported. Additionally,these palynomorphs are accompanied by Pseudoschizaea (seldom) and microforaminiferal test(abundantly), and this cooperation could suggest the presence of a hot water outlet in Gülbahçe Bayduring the Late Holocene period. It can be said that the iron oxide that formed on the microforaminiferal test and variouspalynomorphs is related to the thermal activity in Gülbahçe Bay. According to the palynoflora definedin this study, there could have been humid and hot palaeoclimatic conditions in the study area.Additionally, the “coexistence approach” analysis was used on the palynoflora of the Late Holocene,and numerical palaeoclimatic values were obtained. These results are compared with results from somepalynoflora of the Late Holocene.

Abstract: The study area is located on the southern rim of the Gediz Graben and to the west of Salihli town. In thestudy reported here, the hydrochemical characteristics of these geothermal fields were determined bychemical and isotopic data.The Menderes Massif rocks, which are formed by highly fractured karstic marbles, granodiorite,gneiss and guartz-schist units, are aquifers of the geothermal systems in the study area. The Neogeneterrestrial sediments, which are made up of alluvial deposits, act as cap rocks for the geothermalsystems. Alluvium is the most important unit for cold ground water production. The thermal springs inthe Sart-Çamur Spa have an outlet temperature of 52 °C and a 5 l/s discharge. Thermal fluid with atemperature of 155 ºC and a 2 l/s discharge was recorded at the drilling well, a well 1189 m deep, in theCaferbey geothermal field. The circulation of thermal fluid in the subsurface is along the fault andfracture zones.Results of environmental isotope and chemical analyses show that the thermal waters in thestudy area are of meteoric origin and generally have water-rock interactions. According to AIHchemical classifications, these thermal waters reflect the water types Na-Ca-HCO3 and Na-HCO3 in theSart-Camur and Caferbey geothermal fields, respectively. Cold waters are mainly dominated by HCO3¯and SO4¯ ions, with Na+2, Ca+2 and Mg+2 cations. High boron and arsenic contents are among thecontaminants when it comes to irrigation and drinking water sources in area. Because of these,reinjection of the thermal waters in the geothermal aquifer after use them is important, not only torecharge the reservoir but also to prevent harmful effects on the environment. According to variousgeothermometers, reservoir temperatures are calculated as varying between 8 oC and 290 ºC. Thethermal waters in the study area are oversaturated with respect to carbonate minerals (calcite andaragonite). These are most likely to cause scaling problems during extraction and use.

Abstract: In the last years some eminent earthscientists have been proposing to discard the Quaternary from theGeological Time Table, adding the Pleistocene and Holocene to the period Neogene as new Series.However, in May 2009 the International Stratigraphy Commission decided that the Quaternary Periodwould be preserved in the time table, what is more, it enlarged the Neogene-Quaternary boundary from1.8 to 2.6 ma. Such a change or regulation in the Geological Time Table would affect directly theinternal geological studies. Here, recent and possible developments are presented in this subject withadding some comments and suggestions.