Journal of Geological Society of India (Online archive from Vol 1 to Vol 78)

M. Celik ¹, A. Sari ¹

Affiliations
1 Ankara University, Geological Engg. Dept., Tandogan/Ankara, 06100, TR

Abstract

Hydrochemical and isotopic study of groundwaters of Adiyaman region in Turkey is undertaken to classify groundwaters on the basis of their chemical characteristics, and examine their origin. The compositions of groundwaters in the calcareous rocks of the Adiyaman region reflect different combinations of fresh and saline groundwaters. The chemistry of the shallow groundwaters of Komur Municipality Spring(KS)and well of General Directorate of Adiyaman District (FG), and, especially of the major cations, is controlled by local rock compositions. While these are immature groundwaters geochemically, formation waters are generally mature groundwaters.

Based on TDS classification, FG, KS and, Atatiirk Dam Lake (ADL) samples are of fresh water (0-1000 ppm), Adiyaman (A44) and Cemberlita? (C14) formation water samples are of brackish water (1000-10000 ppm), and other formation waters are of connate water (10000-30000 ppm). Adiyaman formation waters (A32 and A44) have a sequence of rCl>rHCO₃>rSO₄ and are undersaturated with respect to CaSO₄. Formation waters of other oil fields have a sequence of rCl>rSO₄>rHCO₃ and are oversaturated with respect to CaSO₄. Conservative ions in formation waters, such as Cl and Br, were used together with total dissolved solids in determining the evolution of waters and in the evaluation of mixing. In this respect, there is a transition between fresh and connate waters. It is concluded that Adiyaman and Cemberlitas formation waters show greater mixing with fresh groundwaters than other formation waters of the Adiyaman region.

Keywords

Formation Waters, Calcareous Rocks, Geochemistry, Isotopes, Upper Cretaceous, Turkey.

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S. Aliyev ¹, A. Sari ², M. Ergin ²

Affiliations
1 Ankara University, Department of Geological Engineering, 061 OO,Tandogan, Ankara, IN
2 Ankara University,Department of Geological Engineering, 06 100,Tandogan, Ankara, TR

Abstract

The samples used in this study are mollusc shells that were obtained from core sediments taken at 60 m water depths from the Southern Marmara Sea, close to the Kapidag Peninsula. The ages of samples ranged from Late Pleistocene to Early Holocene. In two cores, analysis were carried out on mollusc fossils for δ¹⁸O and δ¹³C isotopes. The δ¹⁸O and δ¹³C values of mollusc shells ranged between 0.20 %O and -3.0 %O and 0.08 %O and 0.8 1 %o, respectively. δ¹⁸O and δ¹³C display independent and different values that are inversely related with each other. The lowest δ¹⁸O values are associated with highest δ¹³C values. The variations in oxygen and carbon isotopic values are independent from each other and reflect changes in palaeogeographic environment. The varying isotopic temperature values between 1 3.0°C and 27.6°C proves changing palaeoenvironmental conditions in the basin. The isotopic temperature and δ¹⁸O and δ¹³C data for the Late Quaternary times (for W2-H L1) in the Marmara Sea are obtained in this study for the first time.

Keywords

Stable Isotopes, Carbon And Oxygen, Palaeotemperatures, Mollusc Shells, Marmara Sea.

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