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    Antroposen ve Antropojenik Kirlilik Sayısı, Önsöz
    (TMMOB Jeoloji Mühendisleri Odası, 2020) Sümer, Ökmen; Yücel, Deniz Şanlıyüksel; Baba, Alper
    1947 yılından beri düzenlenen Türkiye Jeoloji Kurultayları, her yıl değişen temaları ile ulusal ve uluslararası platformlarda, ülkemizin en saygın bilimsel etkinliklerinden biridir. Yetmiş ikinci Türkiye Jeoloji Kurultayı, 28 Ocak - 1 Şubat 2019 tarihleri arasında Ankara’da “Kent Jeolojisi” teması ile gerçekleştirilmiştir. Türkiye Jeoloji Kurultayları kapsamında ilk defa düzenlenen “Antroposen ve Antropojenik Kirlilik” oturumu, farklı disiplinlere sahip araştırmacıların sunduğu çalışmalarla ilgi toplayan oturumlardan birisi olmayı başarmıştır. Gösterilen bu ilgi sonucunda; oturumda sunulan seçilmiş bildirilerin Türkiye Jeoloji Bülteni’nde hazırlanacak olan bir sayıda hakemli makale olarak yayınlanması fikri gündeme gelmiştir. Bu bağlamda, ana çatısı “Antroposen ve Antropojenik Kirlilik” oturumu olmak üzere aynı bilimsel konu üzerinde yoğunlaşan ve çoğunluğu 72. Türkiye Jeoloji Kurultayı’nda sunulmuş bildirilerden üretilen bu sayı oluşturulmuştur.Sanayi Devrimi’nden günümüze küreselleşen Dünya’da insanoğlu doğayı değiştirmektedir. Her geçen gün artan sanayileşme, kentleşme, fosil yakıtların kullanımı, kontrolsüz tarım ve madencilik faaliyetleri, atık suların çevreye deşarjı gibi antropojenik etmenler sonucunda ortaya çıkan organik ve inorganik kirleticilerin cins ve miktarları artarak çevrenin doğal yapısı bozulmaktadır. Endüstrileşme ve yaşam biçimlerindeki değişmeye paralel olarak ortaya çıkan atıklar zaman içinde logaritmik bir artış göstererek bu atıklardan kaynaklanan çevre sorunları küresel bir boyut kazanmıştır. Küresel ısınma, asit yağmurları gibi faktörler antropojenik etki ile oluşan çevre sorunlarından sadece birkaç tanesidir. Özellikle As, Al, Fe ve Mn gibi metal(loid)ler yerüstü ve yeraltı sularına karışarak insan sağlığında olumsuz etkilere sebep olmaktadır. Gelecek nesillere yaşanabilir bir Dünya bırakmak için bilinçli çevresel sürdürülebilirliğin ön plana çıkarılması gerekmektedir.Antropojenik kirlilik çalışmaları dünyada ilk kez 19. yüzyılın ortalarında, ülkemizde ise 20. yüzyıldan itibaren yoğun olarak çalışılan bir araştırma alanı olmuştur. Özellikle 2000’li yılların başlarından itibaren antropojenik etkilerin, jeolojik kayaçlar veya olaylarda gözlenebilir ve ölçülebilir olmasından yola çıkarak, içinde bulunduğumuz jeolojik seri olan Holosen’in zamansal olarak ayrılması ve Antroposen şeklinde yeni bir jeolojik seriye girilmesi gerektiği fikri bilim camiasında yeniden gündeme getirilmiş ve kısa zamanda çok tartışılan bir bilimsel konu haline gelmiştir. Bu noktada, antropojenik kirlilik ve Antroposen’in zamansal olarak ayrılması çalışmaları disiplinler arası bir araştırma alanı olup, yer, deniz ve atmosfer bilimlerini kapsayan geniş bir etki alanına sahiptir. İlginize sunduğumuz bu sayı farklı disiplinlerden bilim insanları tarafından titizlikle üretilmiş, konusunda uzman hakemler tarafından değerlendirilen nitelikli çalışmaların sonuçlarını içermektedir
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    Assessment of the water quality of Troia for the multipurpose usages
    (Springer, 2007) Ozcan, Hasan; Ekinci, Huseyin; Baba, Alper; Kavdir, Yasemin; Yuksel, Orhan; Yigini, Yusuf
    The aim of this study was to determine the origin and quality of waters in Troia. For this purpose total of 25 water samples including 2 springs, 14 surfaces and 9 groundwaters, were collected at eight different times. Global positioning system (GPS) was used to determine to coordinates of sampling points. The concentration of 6 minor elements (B, Cu, F, Fe, Pb and Zn), 9 major anions and cations (Na(+), Ca(2+), K(+), Mg(2+), SO(4)(2-), PO(4)(3-), HCO(3)(-), Cl(-) and, CO(3)(2-)) were determined by spectrometric, colorimetric and volumetric methods. Water pH, EC, DO, ORP and TDS were measured in situ using probes. The data showed that the concentrations of most of minor elements were below the EPA and TSE limits except Pb which ranged between 0.001 and 4.832 mg L(-1). Statistically significant relationships (P < 0.01 and r > 0.70) were observed between Fe and Cu, Cu and K(+), Cu and Ca(2+), B and Na(+), Na(+) and K(+). Assessing the water based on irrigation using Wilcox model showed that some well waters were not suitable for irrigation. Troia water was found to be highly corrosive and the average corrosion coefficients varied from 0.5 to 4.6. According to the Piper and Schoeller diagrams results, the water in Troia was classified as mixed water type.
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    Çan jeotermal alanı’nın hidrojeokimyasal ve hidrojeolojik incelenmesi
    (2010) Deniz, Ozan; Baba, Alper; Tarcan, Gültekin
    Çan Jeotermal Alanı, Türkiye’nin kuzeybatısında bulunan Biga Yarımadası’nın orta bölümünde yeralır. Çan çevresinde gözlenen baskın kaya tipi volkanitlerden oluşur. Bu kayaçlarda ayrışma zonları ve kil mineralleri oldukça yaygındır. Bunun yanında bölgede gözlenen diğer jeolojik birimler tortul kayaçlar, düşük dereceli metamorfitler ve alüvyondan oluşur. Jeolojik birimler bölgedeki tektonik aktivite nedeniyle yaygın olarak kırık zonları içerir. Termal sular yüzeye bu kırık zonları yoluyla ulaşır. Çalışma alanında gözlenen litolojiler arasında alüvyon en verimli akiferdir. Bu birimdeki sondajların verimleri 5-30 L/s arasındadır. Bu birimin transmissibilitesi ve geçirimlilik katsayısı sırasıyla 50-421 m2/gün ve 1.01-16.8 m/gün arasındadır. Yeraltı suyu derinliği 0.1-8.3 m arasında değişmektedir. IAH (1979)’da verilen su sınıflandırma yöntemine göre termal sular Na-Ca-SO4 tipinde, soğuk sular Ca-Mg-HCO3 tipinde ve kar örnekleri karışık tipte sulardır. Sıcak suların sıcaklık, elektriksel iletkenlik ve pH değerleri ortalamaları sırasıyla 44.4°C, 2941 µS/cm ve 6.9’dur. Jeotermal sistemin rezervuar akışkan sıcaklığını tahmin etmek için jeotermometre eşitlikleri kullanılmış ve 46-203°C arasında değişen sıcaklıklar elde edilmiştir. ?D, ?T ve ?18O izotop analizleri Çan bölgesindeki termal suların meteorik kökenli ve en az 45-50 yıllık olduğunu göstermiştir.
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    Çan kömür havzasındaki madencilik faaliyetlerinin tıbbi jeoloji açısından değerlendirilmesi
    (2008) Baba, Alper; Save, Dilşad; Gündüz, Orhan; Gürdal, Gülbin; Bozcu, Mustafa; Sülün, Serdar; Özcan, Hasan
    [Abstract Not Available]
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    Change detection and visualization of acid mine lakes using time series satellite image data in geographic information systems (GIS): Can (Canakkale) County, NW Turkey
    (Springer, 2014) Yucel, Deniz Sanliyuksel; Yucel, Mehmet Ali; Baba, Alper
    Can, a county in the province of Canakkale, is one of the most prominent coal mining districts in Turkey. Many mining companies have been operating coal deposits for power generation and district heating in this region since 1980. Generally, small and medium-scale mining companies operate for short periods and abandon the operational land without providing any rehabilitation. Human intervention in the natural structure and topography of the earth surface causes large holes and deterioration in these areas. Artificial lakes occur because of surface discharge and underground leakage into abandoned open pit mines with high lignite sulfur content (0.21-14.36 wt %). Furthermore, these lakes gain acidic character due to acid generation from pyrite oxidation. Acid mine lakes are highly acidic (pH < 3.05) and have elevated concentrations of , Fe and some metals. The main objective of this study is to evaluate the environmental conditions and demonstrate the development of a monitoring system for their possible changes in the acid mine lakes of the open cast lignite mining area on a regional scale. For this purpose, the data received from remote sensing satellites were used. Areal change detection and perimeter changes of nine acid mine lakes caused by coal mining companies in Can from 1977 to 2011, were determined using Landsat, Quickbird and Worldview satellite images. As a case study, an area of 9 km(2) was chosen for the variety of acid mine lakes. Using GIS software, satellite images were analyzed in time series, borders of acid mine lakes were digitized and converted into vector data format. At this stage, prior to the digitization, in order to create contrast on the satellite images, stretch type and stretch values were changed. The areal and perimeter changes were computed and presented via tables and graphics. In addition, thematic maps of the acid mine lakes were created and visualized. The results show that the number of acid mine lakes increased and these caused environmental risks due to their hydrochemical properties and areal increments.
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    Determining water and sediment quality related to lead-zinc mining activity
    (Polska Akad Nauk, Polish Acad Sciences, Inst Environ Eng Pas, 2018) Yucel, Deniz Sanliyuksel; Baba, Alper
    This study focuses on the Koru and Tesbihdere Pb-Zn mining districts. located at the upstream areas of the Umurbey dam basin. Mining activities in Koru, one of the longest operated mines in NW Turkey, date back to the beginning of the 1900s. The purpose of the study is to (1) determine the hydrochemical properties of the water resources and to assess the potential environmental consequences of mining activities in the Koru and Tesbihdere mining districts, and (2) investigate the effects caused by mining activities on the water resources and sediment quality in the Umurbey dam basin. Concentrations of As, Cd. Cu, Fe. Mn, Pb, and Zn in river sediments downstream of the Tesbihdere and Koru mining district, and in the Umurbey darn sediments were higher than the world average for river sediments. The geoaccumulation index and enrichment factor revealed that sediments were strongly polluted with Pb and Zn, moderately to strongly polluted with Cd and moderately polluted with Cu. The chemical analyses of water resources revealed that the maximum Fe, Zn, Pb, Mn, and Cu concentrations reached 2890 mu g/l, 1785 mu g/l, 1180 mu g/l, 984 mu g/l. and 419 mu g/l, respectively. The Koru River is classified as polluted water according to Turkish inland water quality regulations. The environmental contamination problems in the local drainage system are caused by leakage from past and current tailing ponds into the Koru River.
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    Direct Quantitative Determination of Total Arsenic in Natural Hotwaters by Anodic Stripping Voltammetry at the Rotating Lateral Gold Electrode
    (Bentham Science Publ Ltd, 2009) Yilmaz, Selehattin; Baba, Baris; Baba, Alper; Yagmur, Sultan; Citak, Meryem
    A simple, rapid, selective and sensitive differential pulse anodic stripping voltammetric (DPASV) technique for the direct quantitative determination of inorganic total arsenic in natural hotwater was developed. The electrochemical determination of total arsenic has been carried out at the novel rotating lateral gold electrode in hydrochloric acid solution (37 % w/w). The analysis was performed with a special gold electrode whose active surface was located on the side. Reproductivity of measurement was achieved by the conditioning of the gold electrode. This was done every day before the measurements as well as when the background current varied strongly from measurement to measurement. The determination limit of 0.5 mu g L-1 was achieved with 10 mL sample solution. The total arsenic concentration was made by appropriate selection of the deposition potential. During the deposition step, the total arsenic content was reduced at -1200 mV by nascent hydogen to As degrees. During the subsequent voltammetric determination, the preconcentration As degrees was again oxidized to determine the level. The method was applied successfully to the direct quantitative determination of total inorganic arsenic in hotwater. In order to show the accuracy of the results developed from voltammetric technique, the values obtained were compared with those obtained from inductively coupled plasma mass spectrometry (ICP-MS).
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    Effect of High Aluminum Concentration in Water Resources on Human Health, Case Study: Biga Peninsula, Northwest Part of Turkey
    (Springer, 2010) Bakar, Coskun; Karaman, Handan Isin Oezisik; Baba, Alper; Sengunalp, Fatma
    Widespread and intense zones of silicified, propylitic, and argillic alteration exist as outcrop around the Biga Peninsula, NW Turkey. Most of the springs in the study area surface out from these altered volcanic rocks. The concentrations of aluminum (Al) in these springs ranged from 13.17 to 15.70 ppm in this region. These high levels of Al were found to exceed the maximum allowable limits (0.2 ppm) depicted in national and international standards of drinking water quality. Therefore, the effect of high Al in water resources on human health was evaluated in this research. A total of 273 people aged above 18 years and living in the Kirazli region (whose water supply is from springs emerging from these alteration zones) and in the Ciplak-Halileli region (whose water supply is provided from an alluvium aquifer) were selected as the research group. For this group, a questionnaire was completed that contained questions on descriptive characteristics of humans and a Mini-Mental State Examination (MMSE) was administered by the authors using the face-to-face interview technique. A neurological examination was then performed by the neurology specialist as a second-stage investigation. Finally, 10 ml of venous blood samples were obtained from these people as a third-stage analysis to determine the serum Al levels together with vitamin B-12, folic acid, and thyroid-stimulating hormone parameters. The result typically revealed that the MMSE score was less in 31.9% and there was no statistically significant difference between the two regions. However, the result also showed that neuropathy in the history (including a careful past medical history) was significantly higher in the Kirazli region.
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    Effects of fly ash from coal-burning electrical utilities on ecosystem and utilization of fly ash
    (Springer, 2006) Baba, Alper; Usmen, Mumtaz A.
    Electric power plants that bum fossil fuels emit several pollutants linked to the environmental problems of acid rain, urban ozone, and the possibility of global climate change. Not only are gaseous and particulate emissions from coal-fired power plants of environmental concern, but also their. byproduct, fly ash may lead to contamination because of the possible release of both major and trace elements. Although there are serious efforts to use fly ashes as construction materials or soil amendments, the amount of the stocked waste ash keeps increasing because production exceeds the amount that can be used in the construction industry. Waste ash that cannot be used in above-mentioned industries needs to be disposed of. The safe disposal of waste ashes requires adequate identification and classification of their heavy metals as well as their toxicity levels. This paper summarizes the effects of the fly ash from coal-burning electrical utilities on ecosystems and provides information about how to beneficially use this kind of ash.
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    Effects of leachant temperature and pH on leachability of metals from fly ash. A case study: Can thermal power plant, province of Canakkale, Turkey
    (Springer, 2008) Baba, Alper; Gurdal, Gulbin; Sengunalp, Fatma; Özay, Özgür
    Lignite powered electric generation plants result in increasing environmental problems associated with gaseous emissions and the disposal of ash residues. Especially, low quality coals with high ash content cause enormous quantities of both gaseous and solid fly ash emissions. The main problem is related to the disposal of fly ash, which, in many cases, contains heavy metals. It is known that toxic trace metals may leach when fly ash is in contact with water. In this study, fly ash samples obtained from the thermal power plant in the town of Can in Turkey were investigated for leachability of metals under different acidic and temperature conditions. The experimental results show that a decrease in pH of the leachant favors the extraction of metal ions from fly ash. A significant increase in the extraction of arsenic, cadmium, chromium, zinc, lead, mercury, and selenium ions from the ash is attributed to the instability of the mineral phases. These heavy metals concentrations increase with respect to increasing acidic conditions and temperature. Peak concentrations, in general, were found at around 30C.
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    Effects of mining activities on water around the Canakkale plain, Turkey
    (Springer, 2007) Baba, Alper; Deniz, O.; Guelen, O.
    Can region is rich in clay mines and lignite deposits. Results of major anion-cation and some trace elements in groundwater and surface water around the Can Plain, showed that groundwater is very reach with calciurn-magnesium-sulfate (Ca-Mg-SO4). Its aluminum (Al) concentrations are more than the acceptable maximum standard value. The results show that mining activity has contaminated water sources. The heavily polluted water is Currently under the international standard value around the plain. However, if precautions are not taken, these contaminants may spread in surface water and groundwater.
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    Enrichment of trace element concentrations in coal and its combustion residues and their potential environmental and human health impact: Can Coal Basin, NW Turkey as a case study
    (Inderscience Enterprises Ltd, 2016) Baba, Alper; Gurdal, Gulbin; Yucel, Deniz Sanliyuksel
    In this study, the variation of trace element concentrations ( total of 48 trace elements including rare earth elements) in coal, coal ash and fly ash were examined and compared with coal Clarke values. Results showed that the average concentrations of trace elements including As, B, Cu, Ce, Co, Cs, Gd, Hf, La, Lu, Mo, Nd, Nb, Pr, Pb, Sc, Sm, Ta, Tb, Th, U, V, W, Y, Yb, Zn and Zr in the Can Basin coals are higher than their respective Clarke values for world low-rank coals. The elements As, Cu, Co, Cs, Mo, Nb, Sc, Pb, Pr, Th, U, V, Zn and Zr are enriched in coal ashes, whereas As, Co, Nb, Sc, U and V are enriched in fly ashes. Among the elements, maximum enrichment in coal was observed for As, with the average concentration of 253.5 ppm As in the Can Basin coals, while the coal Clarke value is 14 ppm and world average value is 8.3 ppm. From the ecotoxicological point of view, combustion residues formed by indoor combustion of coal and/or in thermal power plants may be a hazard to the environment and to aquatic and terrestrial life including human beings, particularly As, trace elements and released radioactive elements.
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    Environmental impact of the utilization of geothermal areas
    (Taylor & Francis Inc, 2006) Baba, Alper; Armannsson, Halldor
    Turkey is one of the fastest growing power markets in the world and is facing an ever-increasing demand for power in the coming decades. Geothermal is one of its important renewable energy sources; Turkey is rated the 7th country in the world in terms of geothermal potential. The country's installed capacity is 992 MWt for direct use and 20.4 MWe for power production. These are expected to almost triple in the next ten years and more than quadruple in the next twenty years. Geothermal energy is generally accepted as being an environmentally benign energy source. Geothermal development over the last forty years in Turkey has shown that it is not completely free of impacts on the environment. Environmental impacts are projected to limit the use of this needed energy resource. Geothermal waters of Turkey are highly mineralized with elevated levels of arsenic ( As), boron ( B), cadmium (Cd), and lead (Pb), resulting in scaling and corrosion. Because they are not reinjected, geothermal discharges also result in an observed contamination of soil and waterways. Reinjection is recommended to be installed as a standard procedure to avoid these adverse impacts.
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    Generation of Acid Mine Lakes Associated with Abandoned Coal Mines in Northwest Turkey
    (Springer, 2016) Yucel, Deniz Sanliyuksel; Balci, Nurgul; Baba, Alper
    A total of five acid mine lakes (AMLs) located in northwest Turkey were investigated using combined isotope, molecular, and geochemical techniques to identify geochemical processes controlling and promoting acid formation. All of the investigated lakes showed typical characteristics of an AML with low pH (2.59-3.79) and high electrical conductivity values (1040-6430 mu S/cm), in addition to high sulfate (594-5370 mg/l) and metal (aluminum [Al], iron [Fe], manganese [Mn], nickel [Ni], and zinc [Zn]) concentrations. Geochemical and isotope results showed that the acid-generation mechanism and source of sulfate in the lakes can change and depends on the age of the lakes. In the relatively older lakes (AMLs 1 through 3), biogeochemical Fe cycles seem to be the dominant process controlling metal concentration and pH of the water unlike in the younger lakes (AMLs 4 and 5). Bacterial species determined in an older lake (AML 2) indicate that biological oxidation and reduction of Fe and S are the dominant processes in the lakes. Furthermore, O and S isotopes of sulfate indicate that sulfate in the older mine lakes may be a product of much more complex oxidation/dissolution reactions. However, the major source of sulfate in the younger mine lakes is in situ pyrite oxidation catalyzed by Fe(III) produced by way of oxidation of Fe(II). Consistent with this, insignificant fractionation between delta(34) and delta(34) values indicated that the oxidation of pyrite, along with dissolution and precipitation reactions of Fe(III) minerals, is the main reason for acid formation in the region. Overall, the results showed that acid generation during early stage formation of an AML associated with pyrite-rich mine waste is primarily controlled by the oxidation of pyrite with Fe cycles becoming the dominant processes regulating pH and metal cycles in the later stages of mine lake development.
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    Geochemical and radionuclide profile of Tuzla geothermal field, Turkey
    (Springer, 2008) Baba, Alper; Deniz, Ozan; Ozcan, Hasan; Erees, Serap F.; Cetiner, S. Ziya
    Tuzla geothermal basin is situated in north-western Turkey on the Biga Peninsula, which is located at the west end of the Northern Anatolian Fault system. Soil and water samples were collected between August 2003 and June 2004 to initiate development of a geochemical profile of surface and subsurface waters in the geothermal basin and radionuclide concentrations in soils. All water samples were found to fall within Turkish Water Quality Class 4, meaning they were remarkably contaminated for any water consumption sector (industrial, human use or agricultural) based on sodium and chloride ions. Such waters could be used only after appropriate water treatment. The water samples are of the chloride type in terms of geochemical evaluation. Preliminary geochemical evidence shows that the N-S flowing part of the Tuzla River acts as a natural barrier within the basin. Heavy metal concentrations in the soil samples show slight elevations, especially those obtained from the east part of the basin where thermal springs are dominant. Geochemical calculations were carried out with PHREEQC (R) software to determine equilibrium concentration of chemical species and saturation indices, by which it is suggested that chloride is the most important ligand to mobilize the heavy metals in the studied system. In addition, the activity concentration and gamma-absorbed dose rates of the terrestrial naturally occurring radionuclides were determined in the soil using gamma-ray spectrometry. The soil activity ranged from 42.77 to 988.66 Bq kg(-1) (averaging 138 Bq kg(-1)) for (238)U, 13.27 to 106.31 Bq kg(-1) (averaging 32.42 Bq kg(-1)) for (232)Th, and 99.28 to 935.36 Bq kg(-1) (averaging 515.44 Bq kg(-1)) for (40)K. The highest value of (238)U was found in the soil samples obtained from an area close to the hot spring.
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    Geochemical Characterization of Acid Mine Lakes in Northwest Turkey and Their Effect on the Environment
    (Springer, 2013) Yucel, Deniz Sanliyuksel; Baba, Alper
    Mining activity generates a large quantity of mine waste. The potential hazard of mine waste depends on the host mineral. The tendency of mine waste to produce acid mine drainage (AMD) containing potentially toxic metals depends on the amounts of sulfide, carbonate minerals, and trace-element concentrations found in ore deposits. The acid mine process is one of the most significant environmental challenges and a major source of water pollution worldwide. AMD and its effects were studied in northwest Turkey where there are several sedimentary and hydrothermal mineral deposits that have been economically extracted. The study area is located in Can county of Canakkale province. Canakkale contains marine, lagoon, and lake sediments precipitated with volcanoclastics that occurred as a result of volcanism, which was active during various periods from the Upper Eocene to Plio-Quaternary. Can county is rich in coal with a total lignite reserve > 100 million tons and contains numerous mines that were operated by private companies and later abandoned without any remediation. As a result, human intervention in the natural structure and topography has resulted in large open pits and deterioration in these areas. Abandoned open pit mines typically fill with water from runoff and groundwater discharge, producing artificial lakes. Acid drainage waters from these mines have resulted in the degradation of surface-water quality around Can County. The average pH and electrical conductivity of acid mine lakes (AMLs) in this study were found to be 3.03 and 3831.33 mu S cm(-1), respectively. Total iron (Fe) and aluminum (Al) levels were also found to be high (329.77 and 360.67 mg L-1, respectively). The results show that the concentration of most elements, such as Fe and Al in particular, exceed national and international water-quality standards.
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    Geomorphological investigation of the excavation-induced Dundar landslide, Bursa, Turkey
    (Taylor & Francis Ltd, 2008) Erginal, Ahmet Evren; Turkes, Murat; Ertek, T. Ahmet; Baba, Alper; Bayrakdar, Cihan
    This paper discusses the occurrence and development of the excavation-induce deep-seated landslide, which took place near Dundar village, located west of Orhaneli town in northwestern Turkey. The event occurred in the Bursa-Orhaneli lignite field, which has been actively operating since 1979. Due to undermining of a gently inclined slope (10 degrees) to extract a coal seam, primary tension cracks, which were precursors of the movement, were first observed in the northern head area in mid- to late October 2003. This movement happened simultaneously with precipitation that was significantly above long-term average measured at a nearby climatology station (Keles). This precipitation amount is characterized statistically by a significant standardized anomaly of 1.6. The majority of the monthly precipitation total in October 2003, which mainly consisted of rain showers and thunderstorms, occurred in the last week of the month. By April 2004, rotational failure continued intermittently. After a relatively wet (rainy and snowy) period from January 2004 to April 2004, the main rotational slump occurred in late April 2004, causing the entire destruction of Dundar village's cemetery. Daily climatic and synoptic meteorological data have proved that heavy showers in late April may had triggered the last slump by producing rain showers of 19.3 mm and 19.9 mm daily total on 27 and 28 April 2004, respectively. Field observations carried out along the main head scarp have shown that the slope failure was facilitated by a pre-existing normal fault with an east- west direction and 80 degrees dip. Grain-size analysis showed that the failure occurred on clayey silt, which forms 55% of the slip surface material. Based on the evidence from X-ray fluorescence and energy dispersive X-ray spectroscopy results, smectite-type clay - a product of the chemical weathering of tuff - was the main constituent of the slip surface material. The landslide occurred over an area of 600 m x 650 m with a total volume of 8775 000 m(3). Approximately 28 hectares of farm land were entirely destroyed and the excavated coal seam was buried. The mining operation was moved to 100 m north of the landslide area near Gumuspinar village. From morphological evidence, it is concluded that excavation activities caused the failure to extend in more than one direction as an enlarging sliding mechanism; this produced a high landslide risk for Gumuspinar village, where the most significant normal fault with a 75 m vertical displacement in a coal-bearing sequence is found in the lignite field.
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    Groundwater quality and hydrogeochemical properties of Torbali Region, Izmir, Turkey
    (Springer, 2008) Tayfur, Gokmen; Kirer, Tugba; Baba, Alper
    The large demand for drinking, irrigation and industrial water in the region of Torbali (Izmir, Turkey) is supplied from groundwater sources. Almost every factory and farm has private wells that are drilled without permission. These cause the depletion of groundwater and limiting the usage of groundwater. This study investigates spatial and temporal change in groundwater quality, relationships between quality parameters, and sources of contamination in Torbali region. For this purpose, samples were collected from 10 different sampling points chosen according to their geological and hydrogeological properties and location relative to factories, between October 2001 and July 2002. Various physical (pH, temperature, EC), chemical (calcium, magnesium, potassium, sodium, chloride, alkalinity, copper, chromium, cadmium, lead, zinc) and organic (nitrate, nitrite, ammonia, COD and cyanide) parameters were monitored. It was observed that the groundwater has bicarbonate alkalinity. Agricultural contamination was determined in the region, especially during the summer. Nitrite and ammonia concentrations were found to be above drinking water standard. Organic matter contamination was also investigated in the study area. COD concentrations were higher than the permissible limits during the summer months of the monitoring period.
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    Hydrochemical and Isotopic Composition of Tuzla Geothermal Field (Canakkale-Turkey) and its Environmental Impacts
    (Taylor & Francis Ltd, 2009) Baba, Alper; Yuce, Galip; Deniz, Ozan; Ugurluoglu, Didem Yasin
    Tuzla is an active geothermal area located in northwestern Turkey, 80 km south of the city of Canakkale and 5 km from the Aegean Coast. Geothermal brine, deriving from this area, contains an abundance of NaCl and a water temperature of 173 degrees C (T1 well at 814 m depth) is typically encountered. The aim of this study was to determine the hydrogeochemical properties of the geothermal brine using both chemical and isotopic data, and to investigate the origin of the geothermal brine in the Tuzla area and the environmental impacts of Tuzla Geothermal Field (TGF). Both geothermal brine and shallow groundwater in the area are of meteoric origin. Isotope results indicate that the hot saline waters (brine) in the Tuzla geothermal field originate from connate water along faults. As the saline water rises to the surface, it mixes with shallow groundwaters in various ratios. In addition, the high sodium (Na) and chloride (Cl) content in the Tuzla Stream, fed from the Tuzla geothermal brine during the dry season, cause an increase in sodium and chloride concentrations in the shallow groundwaters by infiltration into the aquifer. Moreover, salt accumulation on the surface is observed due to the uncontrolled artesian flow of geothermal brine, which adversely affects the salinity of shallow groundwater.
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    Öğe
    Hydrogeochemical and Hydrogeological Investigation of the Çan Geothermal Field
    (TMMOB Jeoloji Mühendisleri Odası, 2010) Deniz, Ozan; Baba, Alper; Tarcan, Gültekin
    The Çan Geothermal Field is located on a central part of the Biga Peninsula in northwest Turkey. Volcanics are the dominant rock type in this region. Alteration zones and clay minerals are very common in these rocks. Sedimentary rocks, low-grade metamorphics and alluvium are other geological units observed around Çan. These units include common fracture zones because of the tectonic activity in the region. Thermal waters have reached the surface via these fracture zones. Alluvium is the most productive aquifer in all geological units. Wells drilled in this unit yield between 5-30 L/s. The transmissibility and permeability coefficients of this unit are of 50-421 m2/day and of 1.01-16.8 m/day, respectively. In this aquifer, groundwater depth changes between 0.1 and 8.3m. According to the IAH 1979 water classification, these thermal waters are of the Na-Ca-SO4 type, the cold waters are of the Ca-Mg-HCO3 type and the snow samples are of a mixed water type. Geothermal waters have a meteoric origin. The mean temperature, electrical conductivity and pH of the thermal waters have values of 44.4oC, 2941 S/cm and 6.9, respectively. Geothermometer equations were used for prediction of reservoir fluid temperatures of the geothermal system and temperature values were obtained between 46 and 203oC. δD, δT and δ18O isotope analysis showes that thermal waters in the Çan region have a meteoric origin and are a minimum of 45-50 years old [TR] Çan Jeotermal Alanı, Türkiye’nin kuzeybatısında bulunan Biga Yarımadası’nın orta bölümünde yeralır. Çan çevresinde gözlenen baskın kaya tipi volkanitlerden oluşur. Bu kayaçlarda ayrışma zonları ve kil mineralleri oldukça yaygındır. Bunun yanında bölgede gözlenen diğer jeolojik birimler tortul kayaçlar, düşük dereceli metamorfitler ve alüvyondan oluşur. Jeolojik birimler bölgedeki tektonik aktivite nedeniyle yaygın olarak kırık zonları içerir. Termal sular yüzeye bu kırık zonları yoluyla ulaşır. Çalışma alanında gözlenen litolojiler arasında alüvyon en verimli akiferdir. Bu birimdeki sondajların verimleri 5-30 L/s arasındadır. Bu birimin transmissibilitesi ve geçirimlilik katsayısı sırasıyla 50-421 m2/gün ve 1.01-16.8 m/gün arasındadır. Yeraltı suyu derinliği 0.1-8.3 m arasında değişmektedir. IAH 1979 ’da verilen su sınıflandırma yöntemine göre termal sular Na-Ca-SO4 tipinde, soğuk sular Ca-Mg-HCO3 tipinde ve kar örnekleri karışık tipte sulardır. Sıcak suların sıcaklık, elektriksel iletkenlik ve pH değerleri ortalamaları sırasıyla 44.4oC, 2941 S/cm ve 6.9’dur. Jeotermal sistemin rezervuar akışkan sıcaklığını tahmin etmek için jeotermometre eşitlikleri kullanılmış ve 46-203oC arasında değişen sıcaklıklar elde edilmiştir. δD, δT ve δ18O izotop analizleri Çan bölgesindeki termal suların meteorik kökenli ve en az 45-50 yıllık olduğunu göstermiştir.