Bursa Dümbüldek Termal Suyunun Hidrojeolojisi

Abstract

“Bursa Dümbüldek Termal Suyunun Hidrojeoloji” adlı tez inceleme alanında yer alan sıcak, mineralli ve soğuk suların hidrojeolojik ve hidrokimyasal özelliklerinin belirlenmesine yönelik çalışmalar yapmak amacıyla İstanbul Teknik Üniversitesi Fen Bilimleri Enstitüsü, Uygulamalı Jeoloji Anabilimdalı’nda Yüksek Lisans Tezi olarak hazırlanmıştır. Çalışma alanı 1/25000 ölçekli topografik haritada Bursa İ20 b2 paftasında yer almaktadır. Saha çalışmalarında bölgenin 1/25000 ölçekli jeoloji haritası revize edilmiştir. İnceleme alanı ve çevresi Mesozoyik ve Senozoyik yaşlı birimlerden oluşmaktadır. Birimler yaşlıdan gence doğru Permiyen yaşlı kireçtaşı blokların yer aldığı Triyas yaşlı Orhanlar Grovağı, Oligosen yaşlı Çataldağ Graniti, Miyosen yaşlı Göbel formasyonu ve bu formasyon ile eş yaşlı olan Mudamköy volkanitleri, Pliyosen yaşlı göl sedimentleri ile tüm bu birimleri uyumsuz olarak örten Kuvaterner yaşlı alüvyon ve yamaç molozlarıdır. İnceleme alanında yer alan jeolojik birimler hidrojeolojik özelliklerine göre pekişmemiş formasyonlar, yaygın ve zengin akiferler ile yerel ve ilişkisiz akiferler olmak üzere; pekişmiş formasyonlar ise yerel taneli, çatlaklı zayıf ve çatlaklı çok zayıf formasyonlar olarak sınıflandırılmıştır ve bölgenin hidrojeoloji haritası yapılmıştır. İnceleme alanında yeraltısuyu kalitesini belirlemek amacı ile bu çalışma kapsamında temsili noktalardan alınan su örneklerinin analizlerinden ve diğer sondaj kuyularının açıldıkları tarihlerde yapılan kimyasal analiz sonuçlarından yararlanılmıştır. Kimyasal analiz sonuçları kullanılarak hidrojeokimya haritası oluşturulmuştur. Ayrıca yeraltısuları içilebilirilik ve çeşitli kullanılabilirlik amaçlarına yönelik (Piper, Scholler ve Scholler içilebilirlik diyagramları; Wilcox ve ABD Tuzluluk laboratuvarına göre) sınıflandırılmıştır. Uluslararası Hidrojeoloji Birliğine göre yapılan sınıflamada sıcak ve mineralli sular Na-Ca-HCO3, soğuk sular ise genel olarak CaHCO3 tipinde olduğu belirlenmiştir. Piper diyagramına göre sıcak su Na+K tipli bikarbonatlı su, mineralli su Na-Ca bikarbonatlı su ve soğuk sular ise Ca+Mg bikarbonatlı sular sınıfında olduğu tespit edilmiştir. Bölgede yer alan diğer soğuk sular ile inceleme alanında yer alan suların aynı kimyasal özellikleri göstermesi beslenim alanlarının aynı olduğunu göstermektedir. Dümbüldek Termal alanı için yapılan jeolojik, hidrojeolojik ve hidrojeokimyasal veriler değerlendirilerek Dümbüldek Termal alanının oluşum modeli kullanım alanları, enerji potansiyeli ve kullanımında karşılaşılan sorunlar üzerinde durulmuştur.

This study has been prepared as Master of Science thesis to clarify geological and hydrogeological characteristics of Bursa Dümbüldek Thermal Water in Applied Geology Engineering Department of the Institute of Science and Technology of Istanbul Technical University. The study area is located in the South Marmara in the NW Turkey. 1:25000 scaled Bursa İ20 b2 sheet was used. The study area is in the south region of Bursa. In this study, a hydrogeological investigation has been performed for Bursa Dümbüldek Thermal Water and surrounding region. The obtained results were given on related tables and charts. In this study, it has been investigated as detailed geological, hydrological and hydrogeological features of Dümbüldek Water. During the field study, 1/25000 scaled geological map of the region has been revised. In order to prepare the geological map, 1/25000 scaled topographic maps, geological compass, geologist hammer and GPS is used. The geology of the whole region was investigated by field studies. The formation of boundaries were determined, also the photographs of the existing units were taken during this stage and interpreted. Within the scope of this study, the previously-conducted General Geology data of a region including the Mustafakemalpaşa have been transferred to the digital medium by using CorelDrawX5 software. Systematic geological cross-sections of the region were prepared by using field measurements and observations for the Dümbüldek Thermal area. The study area and its surroundings are composed of Mesozoic and Cenozoic units. The units from older to younger are Triassic Orhanlar Greywacke including Permian Limestone blocks, Oligocene Cataldağ Granite, Miocene Göbel formation and Mudamköy volcanics contemporaneous with this formation, Pliocene lake sediments and Quaternary alluvium and slope rubbles unconformably overlying over all these units. According to various parameters and hydrological measurements from Meteorological Stations in the study area, groundwater budget was calculated for Mustafakemalpaşa. The study area has an annual precipitation of 581.70 mm. Taking into consideration lithological and structural characteristics in the study area, the units are divided into different hydrogeological areas according to the characteristics such as pores, pore sizes, voids. Geological units in the study area, based on their physical and hydrological characteristics, are grouped as unconsolidated formations (common - rich aquifers, unrelated to local aquifers), and consolidated formations (localgranular aquifers, aquifers are weak, very weak aquifers) to be evaluated. Hydrogeological map of the region were made in the light of this information. The groundwater quality in the different aquifers was described by chemical analyses of the water obtained from thermal, mineral water and cold waters. Using these data an attempt was made to present a synopsis of the hydrochemical conditions in the investigated area. Water samples from the termal water, mineral water and cold waters were collected at October of 2012. In order to find out the hydrogeochemical features and groundwater quality and all water samples taken from representative locations in the thermal area were analysed. In-situ analyses such as T, pH, and electrical conductivity have been performed during field studies. In order to represent aquifer charactersitic, samples obtained from thermal water, mineral water, stream and springs within the research area from 5 locations, have been examined. Thermal and mineral water show asidic characteristics, cold waters show alkaline characteristics according to samples pH values, having regard to EC values, hot and mineral waters are ranked as “suspicious waters” while cold waters are ranked as “good waters”. According to TDS ingredients hot and mineral waters are ranked as “very salty waters”, while cold waters are ranked as “bitterish water”. Moreover, water samples have been analysed for their anions, cations and some trace element contents. Hydrogeochemical map was constructed by using the results of chemical analysis. Furthermore, hydrochemical map gives an insight in the quality of water in the investigation area. To determine the quality of the groundwater, results of chemical analysis were used by using groundwater samples and boreholes in the studied area. According to the chemical analysis results Wilcox, USA Salinity Laboratory, Piper and Schoeller Diyagram has been used and classified. Hydrochemical analysis results of water are evalatued using Piper diagram and water types are determined. Piper and Schoeller Semi-logaritmic diyagrams are both used in order to specify the dominant lithology in the formation chemical composition, and to classify water samples with respect to their chemical composition. Results indicate that they thermal and natural mineral water have Na+K>Ca>Mg and HCO3>Cl> SO4 anions and cations which show that sedimantery and volcanic rocks are dominant in the formation of chemical composition. Cold waters generally have rCa> r(Na+K)> rMg and r(HCO3)> rCl> rSO4 anions and cations which show that carbonate rocks are dominant in the formation of chemical composition. Classifications are specified according to International Association of Hydrogeology, hereunder types of hot and mineral waters are Na-Ca-HCO3 type and types of cold waters are generally CaHCO3 type. According to Piper Diagram hot waters are ranked as Na+K type bicarbonate water, mineral waters are ranked as Na-Ca type bicarbonate water and cold waters are ranked as Ca+Mg type bicarbonate water classes. According to Schoeller diyagram which was made as a result of the chemical analysis of the samples which were taken from the waters in the investigation area, waters are same origin, same aquifer and same feeding ground. Other cold water sources located in same region shows similar chemical properties with the water sources in study area, indicates that recharge areas of this sources are the same. When Sodium Absorption Rate (SAR) is an important parameter for agriculture activities, SAR values has calculated and categorized. Due to SAR values of all waters are smaller than ten (