Hydrogeochemical Characteristics of Bursa Thermal Waters in Marmara Region

Proceedings World Geothermal Congress 2010 Bali, Indonesia, 25-29 April 2010

Füsun S. Tut Haklıdır1 and M. Yılmaz Savaşçın2 1Zorlu Energy Group Avcılar - İstanbul, Turkey, 2Dokuz Eylül University Department of Geological Engineering, Buca- İzmir, Turkey [email protected], [email protected]

Keywords: Bursa, thermal waters, hydrogeochemistry The highest mountain of western Anatolia is Mount Uludağ (2543 m.) and it takes place southwest of Bursa city. Mount ABSTRACT Uludağ was represented Paleozoic age high grade metamorphic rocks (Ketin, 1947; Bingöl et al., 1982) such Bursa city is rich with ground waters, mineral waters and as marbles, amphibolite, gneiss and quartzites and low thermal waters is located in the juxtaposition of West grade greenschists, serpantines and marbles in the region. Anatolian Extensional Zone and the southern branch of Oligocene age granite has been observed high altitude of North Anatolian Fault Zone (NAFZ) in north of Turkey. the mountain also. There are a few cold springs discharge at Besides these different tectonic zones, Uludağ massive, different altitudes on the mountain. which is highest mountain of Western Anatolia, is located in this region. Meanwhile thermal springs discharge at low altitudes, near the center of Bursa in two sites. In thermal springs area, Thermal waters discharge in the center of city at the north Neogene sediments such as conglomerate, sandstone, clay, of Uludağ Pluton, the mineral waters reach the surface limestone and Quaternary travertine and alluvium units has along Nilüfer creek in a tectonic valley at the south west of been observed. the pluton. Cold water springs have been discharged different altitudes from Uludağ to Bursa Plain. 3. TECTONICS 1. INTRODUCTION Turkey was strongly affected by the Alpine-Himalayan orogenic belt. The tectonically active areas are concentrated Within the scope of an international project, the aim of along high stress zones like The North Anatolian strike-slip which was to evaluate the geothermal potential of Bursa fault, The East Anatolian transform fault and graben zones region, besides the geothermal sources in the region, the in Western Anatolia. Western Anatolian is such a surface water, groundwater, snow samples and some tectonically active region in Turkey which has large mineral waters in the south of Uludağ have been analyzed grabens (such as Gediz and Menderes Grabens) association within the context of the project. In this study, the part with extensional tectonic. which concerns only thermal waters of the project has been examined. The northwest of Turkey is affected by The North Anatolian Fault Zone (NAFZ). Especially Bursa city and A comprehensive databank has been formed with the anion, surroundings are affected by south segment of NAFZ and cation (Ca+2, Mg+2, Na+, K+, Cl-, SO -2) analysis, pH, 4 Eskisehir Fault Zone (Figure 2). The segment is called temperature (T), electrical conductivity (EC), total Geyve-İznik Fault and runs north of Bursa (Herece, 1990). dissolved suspend (TDS), water soluble oxygen, - 18 bicarbonate (HCO3 ) and δ O, δD isotope analysis on a - -2 daily basis of some water (Cl , SO4 ) and on a weekly or monthly basis of the specially chosen ones.

2. GEOLOGICAL SETTING Bursa city is located northwest of Turkey (Figure 1).

Figure 2: Tectonic lines of Bursa and surroundings (modified Bozkurt, 2001).

4. HYDROGEOCHEMISTRY In Bursa city, two different thermal water types, so called Çekirge thermal waters and Kükürtlü thermal waters can be determined which are different physical, chemical characteristics and geographical positions.

Çekirge main thermal waters are Vakıfbahçe, Zeyninene, Küplüce springs and they discharge from Neogene age conglomerate, sandstone, clay, limestone formation to Figure 1: Bursa city location map. surface.

1 Tut Haklıdır and Savaşçın

Their water temperatures change 36-46ºC, their Vakõfbahçe conductivity change 500-600 µS/cm and their pH values change 7-7.5 dissolved oxygen change 1.5-11 mg/l depend 600,00 on seasonal effects. 550,00 S/cm) Kükürtlü thermal waters discharge from lower altitudes and µ 500,00 Uludağ metamorphic schists and marbles are aquifer in the EC ( region. Travertine precipitations are observed near the 450,00 4 4 4 4 4 4 4 5 5 0 0 /04 /0 200 9/04 2 6 2 1/ discharge of water in Kaynarca springs. 2/26/0 4/1/04 4/25/0 5/31/0 6/28/0 8/2/ 9/2/ 9/ 11/3/04 12/ 01. 10/12/0 0. 2 Dat e

Figure 4c: Seasonal effects on EC values in Vakıfbahçe spring.

Vakõfbahçe

10,00 2

5,00 (mg/l) Figure 3: Travertine precipitation in Kaynarca region. DissolvedO 0,00

4 4 4 4 4 4 4 4 4 Kükürtlü main thermal waters are Kaynarca and 0 0 0 0 0 0 / / / /0 / /05 6 8 /2 /2/0 6 2 4/1/04 /31/0 2 8/2/04 9 /29/0 2 1/ 1.2 2/ 4/25 5 6/ 9 11/3 1 .0 Karamustafapaşa springs in the region. Kaynarca is the 0 2 hottest spring in the city and its maximum annual Date temperature is 80ºC. Karamustafapaşa spring maximum annual temperature is 60ºC. These spring conductivity changes 850-1390 µS/cm and their pH values change 6.5- Figure 4d: Seasonal effects on dissolved Oxygen values 7.8 and dissolved oxygen values change 2.4-10 mg/l. in Vakıfbahçe spring.

All these hot springs are using in bath and medical purposes 4.2 Seasonal Effects on Hydrogeochemistry in Kükürtlü in hotels in Bursa city. Thermal Waters The hottest spring of Kükürtlü Thermal Waters is Kaynarca 4.1 Seasonal Effects on Hydrogeochemistry in Çekirge spring. Their T, pH, EC, dissolved oxygen values has Thermal Waters monitored for a year (Figure 5a to 5d). The hottest spring of Çekirge Thermal Waters is

Vakıfbahçe spring. Their T, pH, EC, dissolved oxygen Kaynarca values has monitored for a year (Figure 4a to 4d). 90,00

Vakõfbahçe 85,00

50,00 80,00

75,00 C)

45,00 O

T ( 70,00

40,00 65,00 C) O

T ( 60,00 35,00 4 4 4 4 4 4 5 /04 /04 04 0 0 0 /04 /0 /0 /0 /05 0 /1/ 9 3 /2 /28/ /2 1/ 2 /12/ 1/20 2/26 4 4/25/ 5/31/ 6 8/2 9/2/04 9 1 1 1/6 0 1 30,00 Date 4 4 5

/26/04 /31/04 /28/04 /29/04 1/3/04 2/2/04 4/1/0 8/2/0 9/2/04 1/6/0 0/12/05 2 4/25/04 5 6 9 1 1 1 20.01.2004 Date

Figure 5a: Seasonal effects on temperature values in Kaynarca spring. Figure 4a: Seasonal effects on temperature values in Vakıfbahçe spring. Kaynarca

Vakõfbahçe

10,00 10,00

pH 5,00

pH 5,00 0,00

0,00 4 4 4 4 4 4 4 4 4 4 4 5 5 0 /0 /0 /0 /0 /0 / 0 /0 4 4 4 4 4 5 8 /2 /2 9 /6 04 0 0 0 4/1/ 8 9 1/3 2/2 1 /12/0 0 /04 /0 /04 0 /0 1/20/0 2/26/0 4/25/0 5/31/0 6/2 9/2 1 1 0 2 6 8 /2 9/ /3/ 2 2/ 1 4/1/04 /25/04 /31/04 8 9/2/ 1 1/6/05 1 1. 2/2 4 5 6/2 9/2 1 12/ .0 10/ 0 2 Date Date

Figure 4b: Seasonal effects on Ph values in Vakıfbahçe Figure 5b: Seasonal effects on pH values in Kaynarca spring. spring. 2 Tut Haklıdır and Savaşçın

Kaynarca In the city center, thermal waters temperatures has changed between 36-46°C in Çekirge region and 43-80°C in Kükürtlü, their conductivities has changed between 500- 1400,00 600 µS/cm and 850-1390 µS/cm. 1380,00 1360,00

S/cm) 1340,00 Seasonal changes have monitored for the physical µ 1320,00 compositions during a year. According to monitoring EC ( 1300,00 results, although pH values almost stable both in Çekirge

5 4 4 4 04 04 04 4 4 4 4 4 5 and in Kükürtlü regions; temperature, conductivity and 5/ 1/ / 2/0 /0 2/0 28 /2 1/20/0 2/26/0 4/1/0 4/2 5/3 6/ 8/ 9 9/29/ 0 11/3/0 12/ 1/6/0 10/12/0 dissolved oxygen values have changed during a year. These Date changes look effects of Mounth Uludağ. Winter time, after snowfalls to Mounth Uludağ, spring time melted snows mixed with cold waters and goes to Bursa Plain, this process reach to thermal waters at low altitudes. Figure 5c: Seasonal effects on EC values in Kaynarca spring. It shows that there is a fastly interaction thermal waters and cold waters in Bursa region. Kaynarca

REFERENCES Bingöl, E., Delaloye, M., Ataman, G.: Granitic Intrusions in 10,00 2 Western Anatolia: A Contribution of the Geodynamic Study of This Area, Eclogae Geol. Helv., 75, (1982) 5,00 (mg/l) 437-446 Dissolved O

0,00

4 4 Bozkurt, E.: Neotectonics of Turkey-a synthesis. /04 04 05 /2/04 4/1/0 8/2/0 9 1/6/ 1/20/04 2/26 4/25/04 5/31/04 6/28/04 9/29/04 11/3/ 12/2/04 Geodinam. Acta, 14, (2001), 3-30 Date Herece, E.: 1953 Yenice-Gönen deprem kırığı ve Kuzey Anadolu fay sisteminin Biga Yarımadası’ndaki uzantıları, MTA Dergisi, 111, (1990), 47-59 Figure 5d: Seasonal effects on dissolved oxygen values Ketin, İ. Uludağ Masifinin Tektoniği Hakkında. Bull. Geol. in Kaynarca Spring. Soc. Turk. 1, (1947), 61-88 5. CONCLUSION Tut Haklıdır, F.S.: Bursa İli ve Çevresindeki Termal, Cold water springs have been discharged different altitudes Maden ve Yeraltısularının Jeokimyasal İncelemesi. from Uludağ to Bursa Plain and thermal waters discharge in Dokuz Eylül University, PhD Thesis, (2007) 318 P the center of city at the north of Uludağ Pluton.