report geothermal resources - TU Bergakademie Freiberg · Geothermal resources 2 The high...

Doreen Ebert, Katarina Borowski

1

Doreen Ebert, & Katarina Borowski

Field trip: Hydrogeology and environmental geology of middle Europe 2007

Subject: Geothermal resources of Czech Republic and Hungary

Geothermal energy Geothermal energy is defined as “power saved as heat beneath the earth’s surface” (Sanner, 2005). It

is mainly produced by radioactive decay in mantle and crust and less by volcanic activity.

Furthermore, convective and conductive processes support the heat flow in the subsurface. Geothermal

energy is the “most extensively used renewable energy worldwide apart from hydropower” (Hurter

and Schellschmidt, 2003).The amount of electricity produced by geothermal energy ranges from

7,16ct/kWh (electrical power > 20MW) to 8.95ct/kWh (electrical power < 20MW) (3*). In

comparison, electricity produced by water energy is about 7.67ct/kWh at maximum and electricity by

wind power is about 6,16 ct/kWh after having reached the reference yield (3*). Referring to an

average geothermal gradient of 30°C/km, the German geothermal use is upgradable. Focusing on

potential geothermic heat production, the generated electricity would cover 600 times the recent

demand produced by 95% from crystalline basement, 4% from fractured zones and 1% from thermal

aquifers (Paschen et al., 2003).

Introduction Geothermal heat flow in Europe

The surface geothermal heat flow of Europe (see Fig.2.) is typically related to active plate boundaries.

Exceptions are regions affected by intra-plate volcanisms. Focusing on Czech Republic and Hungary,

the heat flow regime is marked by middle scale values. In the Czech Republic, the Eger basin is one of

the regions showing elevated heat flow of 50 to 70 mW/m2 (see Fig.3.). In comparison, the Hungarian

heat flow regime is obviously higher ranging from 90 to 140 mW/m2 (see Fig.4.). The highest values

can be found in the north eastern part of Eger and Miskolc. There, the heat flow distribution is

commonly about 100 mW/m2.

Geothermal reservoirs

Geothermal waters are used in cure tourism and balneology. Related to the temperature and their ionic

content, they are qualified for improvement of several illnesses

In addition, geothermal reservoirs are used in energy production. There are three different types of

reservoirs related to depth and temperature. But one assumption has to be fulfilled to achieve

economic interest. The recharge of the reservoir waters has to be persistent.

Geothermal resources

2

The high temperature reservoirs are bound to active magmas in volcanic settings. There the

temperatures reach more than 150°C (Meinhold, 1984). By conduction, the magma heats up reservoir

waters close by. Typical reservoirs are permeable deposits on the one hand or fracture zones in

impermeable rocks on the other hand (Meinhold, 1984). Especially, fractured zone may reach up to the

earth’s surface forming thermal springs (Meinhold, 1984). During migration upward, the reservoir

waters partly become degassed by pressure relaxation. The waters and gases derived from high

temperate realms are used for power generation in turbine power plants. A special case of high

temperature reservoirs are dry reservoirs which lack in water. Their economic use depends on

minimum temperature at a maximum depth and the present stress field consitions (Genter et al., 2003).

The technique is known as Hot Dry Rock or Hot Fractured Rock method. By fact, the term “hot”

refers to a minimum temperature of 200° in five kilometres depth (Genter et al., 2003). According to

Genter et al. (2003), these conditions are the most efficient for electricity generation although

temperatures of more than 100 °C are adequate for economic production as well (Burchardt et al.,

2005). The method bases on injection of high pressured water into the “hot” rock zone. Reactivating

old fractures and creating new ones, the waters travels trough the rock. The initial high pressure is

calculated so that the fractures stay open after pressure decrease as well (Meinhold, 1984). The

injected water heats up by conductional processes in the rock until it is forced out a second borehole.

Then the produced hot water is transformed into electricity by turbines. In Europe, the most promising

resources for HFR are related to the Alpine region (Genter et al., 2003). Peri-Alpine and inner-Alpine

basins are of major economic interest (Genter et al., 2003).

Medium temperature reservoirs refer to aquifers located at depth down to two kilometres (4*). There,

the reservoir waters reach temperatures between 100 and 150°C (Meinhold, 1984). The geothermal

energy is delivered by deep hydrothermal convectional systems (Meinhold, 1984). The convective

processes are forced by the temperature-based expansion of water and its decrease in kinematic

viscosity and density (Meinhold, 1984). According to Meinhold (1984), medium temperate reservoirs

produce more liquid than gaseous pore fluids. In these hydrothermal system, the volumetric extant and

the direction of the permeable zone of is difficult to predict. Therefore any artificial recharge of the

reservoir water is complicated (Meinhold, 1984).

The Low temperature reservoirs refer to more shallow aquifers. They are characterized by porous and

high permeable deposits in depth of 400 metres at maximum (Meinhold, 1984, 4*). The use of low

temperate hydrothermal reservoirs bases on water circulation, too (4*). The energy exchange between

warm ground waters and injected water is a major component of this system (4*). Returning to

surface, the received thermal energy of the water can be transformed into electricity. Commonly, the

low temperate reservoirs are active recharge system which will hold balance in respect to economic

treatment (Meinhold, 1984).


3

Origin of reservoir water

In hydrothermal reservoirs, the natural water level is stationary although water is constantly removed

(Elder, 1981). Therefore, there has to be a sufficient recharge system (Elder, 1981). The waters may be

derived from meteoric systems, from juvenile waters or represent mixed systems (Elder, 1981). Any

differentiation bases on isotopic composition of oxygen and hydrogen.

Meteoric waters are depleted in the lighter 16O isotopes by evaporation processes and therefore the

δ18O increases. Simultaneously, the amount of 1H-isotopes decreases and the fluid becomes enriched

in Deuterium. According to isotopic analyzes, 95% of the thermal springs in the USA are supplied by

meteoric waters (Meinhold, 1984).

Neutral ground waters have higher δ18O values than meteoric waters (Elder, 1981). Commonly, they

show a positive oxygen shift about five units which is caused by ionic exchange between percolating

water and rock (Elder, 1981).Therefore, the reservoir fluid is enriched in 18O- isotopes (Elder, 1981).

The δ D values do not change significantly due to little amount of hydrogen present in the rocks

(Elder, 1981). Acidic ground waters (e.g. thermal waters of Yellowstone park) are enriched in both

18O- and D-isotopes (Elder, 1981).

Having been in compositional equilibrium with magmas, juvenile waters theoretically record the δ18O-

values of igneous rocks (Elder, 1981). Commonly, lacking in characteristic isotopic values,

geothermal waters are mixtures of juvenile and meteoric waters (Elder, 1981).

Another possibility to distinguish mantle and crust derived waters is the isotopic composition of

helium. Waters marked by increased He-4 values are formed in the earth crust by decay of uranium

and thorium whereas He-3-isotopes are exclusively produced in the mantle. The ratio of both isotopes

gives indication on origin of the waters.

Regional geology of the Eger basin, Czech Republic The Eger basin is composed of the partial basins of Cheb (Eger), Sokolov and the northbohemian

basin. The Cheb basin is bordered by an NNW-SSW striking fault in the west and an crystalline which

is called Cheb-Domazlice-Trench in the south. In the North East, the subsidence was reached about

300 - 400 meters which shows the maximum content. This causes the up to 32 m mighty lignite layer

that was deposited in the lower Miocene (Burdigalian till lower Helvete). The lignite layers passed

upward into lower sands of the Stare-Sedlo-formation and are overlain by the mudstones of the upper

lower Miocene Cypris-formation and the mighty Pliocene sediments. Towards the top, the fireproof

mudstone of the late Pliocene Vildstein-formation, Pliocene tuff cones of Zelezna Hurka (1-5 Ma) and

Komorni Hurka (0.26-0.85 Ma) follow. The cheb basin belongs to the most seismic active area in the

bohemian massif.

The Sokolov-basin is bordered by fault which predominantly strikes WSW-ESE. The late Eocene

Stare-Sedlo-Formation is overlain by the early Josef-layer-formation. Towards the top, material from


4

the Duppauer Mountains was deposited as volcanic interface layer and is followed by the main lignite

formation with the Anezka (5-12 m thick) und Antonin (20-30 m thick, reach up to 62 m in the SW).

The Duppauer Mountains are a volcanic complex which is up to 400 m thick. After the Vogelberg, it is

the second volcanic complex in Europe related to the dimension. There are many eruptive centres

which have different ages. At the beginning of the early Oligocene, leucite, tephrite and basalt are

deposited. At times, tuffs are interstratified. Dyke Basalts derive from the lower Miocene main

eruptive phase which is the second volcanic phase.

The SW part of the north bohemian basin near Zatec is situated over the magma chamber of the

volcanic complex of the Duppauer Mountains. After the volcanic main phase, the northeast part near

most was lowered. 500 m mighty lower Miocene sediments are layered over lower sand and volcanic

sediments. In the direction of the top, an up to 40 m tick lignite layer was sedimented near Chomutov,

Most and Teplice. In the direction of south, the lignite layer is separated in three parts by sands and

mudstones.

The Bohemian Middle Mountain is bordered by Cretaceous sediments, volcanic Oligocene rocks with

interstratified sediments. Upward, there are grey and red gneiss as well as granitic intrusion, tuff and

volcanic rocks. This unit is up to 400 m thick. Early upper Oligocene basalts and nephelinites are

overlain by tephrite, trachyte and phonolite and simultaneous essexit-lakkolite near below the surface.

At the ending of volcanism in the late Miocene, tuff vent and cone mounts are formed. Between

bohemian Middle Mountain and Jeschken Mountain in the east, there are gang with balsalt, phonolith

and polzenite (Walter, 1995).

Mineral and Thermal waters of the Eger basin Thermal waters arise in the boundary mountain ranges and adjacent basins of the Bohemian massif

(Kakura et al., 1969). They are related to tectonic lines that follow the main tectonic trend of the

Bohemian massif (Krusne Hory und Krkonose-Sudeten) or that are perpendicular to this trend

(Kakura et al., 1969). This joint system is conquering the whole igneous rocks, so that surface waters

migrate down to major depth (Kakura et al., 1969). While passing down, the water is enriched in ions

and carbon dioxide that is ascending from deeper faults (Kakura et al., 1969). Basing on penetration

depth, the waters reach different temperatures (see Terms). The width and distribution of migration

paths strongly vary by geologic background (Kakura et al., 1969). In many places, the waters are

accumulated in artesian aquifers in the lower basin (Kakura et al., 1969). In the Eger basin, the main

water is enriched in sodium hydrocarbon. Partly, it shows dissolved carbon dioxide as well (Kakura et

al., 1969).

Outcrops General information about the geology and industry of the Eger basin were considered at Nové Mesto

– ski station Bourrnak (see Fig.6 way point 001 and Pic.1.). The active Eger basin is and was


5

dominated by coal industry. It was part of the “black triangle” which is located at the cross point of

Czech Republic, Germany and Poland. The landscape of the Eger basin gives evidence of high

environmental pollution (Fig. 5). The dying forest syndrome was induced by the high emission of

sulphur while burning the produced coal. It led to acid rain and mobilization of heavy metals in the

ground. Arsenic and uranium are just two of the well known elements mobilized by the acid rain

which reached pH-values about 2.5. In Teplice, the forced mining resulted in a wide-ranging decrease

of the ground water table. Its known thermal springs of 43°C dried out. But being important for cure

tourism, the construction of deeper wells was a need. They penetrated the deeper aquifers of the Eger

basin and led to reactivation of the cure tourism. Although being still site of mining, the air pollution

decreased in the last years. This improvement on environmental conditions bases on progressing

technology and invention of filter stations.

The major coal production in the Eger basin also influenced the pre-existing infrastructure. The church

of Most is known for its replacement in respect to the open pit mining (see Fig.6, way point 002). In

the 1990ies, the whole building was put on huge steel wheels and replaced some kilometres far (see

Pic. 2). This project was a masterpiece in geological and technical engineering. Relicts of Tertiary

volcanism are frequent in the Eger basin and resemble as basaltic hills (see Pic. 3).

Referring to frequents earth quake swarms in the Vogtland and CO2-bearing thermal springs, the Eger

basin is characterized by recent magmatic activity (see Fig. 5). In the western basin, a north to south

orientated fault is associated by subsequent springs discharging thermal waters of high ionic content.

The springs are alined on 1.5 kilometres and are called “Kollonadenquellen”. In sum, they discharge

500 L/min and the water temperatures range from 43 to 67°C. According to isotopic analysis, the

waters originate from two to three kilometres depth. Their acid character results from interaction with

magmas rich in carbon dioxide. Marked as cure waters, the thermal waters show a high ionic content

as well. It is derived from dissolution of tertiary marine solution residues and meteoric waters.

Increased demand on cure waters led to the exaggerated production of 1.7m/min and the dry out of

most of the former artesian springs. To solve the cure tourism, new wells were drilled that penetrated

deeper aquifers and delivered the demanded waters. The waters of these artificial springs reach

temperatures about 73°C. Since several centuries, Karlovy Vary is one of the most famous places for

Czech cure tourism (see Fig. 6., way point 003 and Pic.4). Its thermal waters are used for external and

internal balneologic purposes and are said to improve digestion and articular diseases.

The springs of Bublak and Soos are located close to Frantikovy Lázni, western Bohemia (see Fig. 6,

way points 004, 005, 006, 007).

They are marked by cold water discharge which is associated by CO2-release. According to isotopic

analysis, the gases of Soos and Bublak originate from the mantle down to 30 kilometres (1*). The


6

studied elements Helium and Carbon give evidence. Focusing on Helium-3, the amount is about 60%

and points to mantle derivation. In comparison, middle ocean ridges are characterized by a content of

Helium-3 about 100%. By now, the Cheb basin has the highest amount of mantle helium in middle

Europe (1*). Referring to Bräuer et al. (2003), the Bublak mofettes have a gas flux o more than

20000L/h and the gas mainly consist of CO2. The carbon dioxide is not dissolved in the water. The

mofettes form a two phase system. Besides groundwater, the mantle-derived CO2 migrates upward and

penetrates the shallow aquifers. The rising of mantle carbon dioxide to the surface bases on local

inversion of the MOHO discontinuity induced by a magmatic intrusion. Furthermore, fault systems

form essential migration paths in the crust. On the last seven to eight kilometres beneath earth surface,

the ascent velocity is about 400m/d (1*). At the surface, the waters degas and produce exhalation holes

up to 0.3 metres in diameter (see Pic. 5.). Radiometric dating of the discharged gases delivered ages

ranging from 10000 to 100000 years. In general, the ionic concentration is high. According to medical

studies, the waters of Soos are qualified as cure water enriched in sulphate. The spring “Kaiserquelle”

of Soos has a concentration of 5.9 g/L and is strongly enriched in iron (see Pic. 6). In contrast, the

Vera spring that is close by just has a low ionic concentration of 0.3 g/L. These differences are caused

by different geological store rocks. In conclusion, there are areas of varying geochemical composition

(see Fig. 7). The Bublak mofettes are marked by strong degassing in distinct places (see Pic. 7).

Finally, the mofettes of Soos and Bublak record the persistent magmatic activity of the Eger basin, too

(Fig. 8.). Scientists from the German UFZ and GFZ proclaimed that the known earthquake swarms

from Vogtland are initiated by the ascent of this degassed magma (1*).

Regional geology of the Bükk unit, Hungary The area around Eger and Miskolc is part of the tectonic unit: Bükk which is located in northwestern

Hungary. Moreover, it is part of the Pelso Megaunit and comprises structures of paleoalpine origin

(Haas et al., 1995, see Fig. 9). According to Trunkó (1969), it is the most complex low mountain range

in Hungary. It consists of Palaeozoic to Mesozoic rocks showing at least two metamorphosed

formations (Nemeth and Madai, 2005). Basing on transpressional tectonics, it is marked by strong

faulting and napping (Trunkó, 1969). Most of these folds and faults show southward-directed

vergency und just some features are northward-directed, mainly in the eastern region (Trunkó, 1969).

The deformation and folding resulted from Alpine tectonics during the Mesozoic (Balogh, 1964). It

was accompanied by dynamo-thermal metamorphism (Balogh, 1964). In Bükk, the northern anticline

is the major tectonic structure and is about 26 km in length (Trunkó, 1969). It is west to east striking

and reaches from Bélapátfalva to Miskolc (Trunkó, 1969). The swell dips eastwards and displays

younger deposits of Mesozoic age there (Trunkó, 1969). Its southern flank is regular and complete

whereas the northern region lacks in several tectonic unit (Trunkó, 1969). Passing to the south the

anticline disappears beneath the Pannonian basin. This is caused by huge normal faults (Trunkó,


7

1969). Until the Tertiary, the mountain range acted as unit. In the middle Miocene, the recent

mountain structure developed. It formed by faulting and thrust faulting (Trunkó, 1969). This event was

accompanied by relative sea-level rise and single colds were over-thrusted (Trunkó, 1969). The thick-

bedded reservoir carbonates formed in the Triassic. They record marine deposition.

In Neogene times, the Bükk mountains were strongly affected by andesitic and rhyolitic volcanism.

The extrusive material was restricted to the southern to southwestern foreland of the Bükk mountains

(Trunkó, 1969).

Thermal waters of Hungary The elevated heat flow in the Hungarian Pannonian Basin results from the general high position of the

earth mantle at 24 km beneath the earth’s surface (Trunkó, 1996). The total reserves in geothermal

energy are estimated on 26.27x1020 kJ whereas only 1/8 is accessible in depth (Trunkó, 1996). This

refers to a maximum depth of about ten kilometres (Trunkó, 1996). The produced geothermal energy

is stored and transported by subsurface waters. Their temperatures range from 25° in shallow to 100°C

in deeper wells (Trunkó, 1996). Apart from younger clastics of the Upper Pannonian, Triassic and late

Eocene limestones and dolomites are the most important reservoir rocks (Trunkó, 1996). The Miscolsk

carbonates contain fossil but mainly open Karst waters. Therefore, they are irregular and occasionally

orientated on tectonic joints (Trunkó, 1996). The waters are mainly used for balneologic purposes and

in spas. At low geothermal gradients, they are just utilized for greenhouse heating, industrial use and

drinking water (Trunkó, 1996). Basing minor vapour exhalations, electricity production is not

economic (Trunkó, 1996). The composition of the thermal waters is strongly related to the host rock

but they are always enriched in sulphur in the Bükk mountains.

Outcrops In the Zsory Spa is located close to Mezökövesd (see Fig. 10, way point 019). Its waters ask for

complex treatment (see Pic.8). According to the high iron and manganese content, there are often

blockages in filters and fractures. Therefore, new well investigation started. But high drilling costs les

to results that are a long time coming. In sum, the concentration of total dissolved solids is high with

3600 mg/L. The concentration of anions is rarely three-times higher than cationic one. Apart from

smaller important contents of iron and manganese, the Zsory waters are dominated by cationic calcium

and sodium as well as anionic hydrogen carbonate and chloride. Isotope analysis show that the water

originates from the watershed of Bükk Mountains. The initial temperature of the water is about 73 –

78°C. For being used in the spa, the water has to be cooled down. The required cold water comes from

the water work of the city. The outflow system is also connected with the city, but the thermal water

directly flows in the river. This environmental impact causes high salt content in the river. Therefore, a

buffer lake is planed which will store the water until it is cooled down. In average, 3200 L/min flow

out, but it differs from summer to winter. The discharge is higher in summer with about 800 L/min


8

than in the month of the winter with about 300 L/min. This causes also inconstant pressure at the

surface which is commonly 3.5 bars. To control the pressure and keep constant, pumps are used. Every

year, 360 000 people visit the spa, whereas 230 000 people come in the warm months from July till

August.

The Egerszalok Spa is situated close to the city of Eger (see Fig. 10, way point 020). It is related to

thermal waters affected by the geothermal gradient of 50°/km. The spa is still under construction

although a little part is already used. The construction began in 2003 and should be regularly finished

in 2010. There are two springs, one of them was drilled in 1961 and the other in 1987. They are only

ten metres in distance but show major differences in hydrochemistry and content of total dissolved

solids. One of the springs has higher sulphur content than the other one. It is supposed that it results

from distinct fault system separating both wells. Both springs are artesian. The increased carbonate

content lead to precipitation of calcrete at the first spring. Huge platforms of calcrete formed in just

little time of 20 years (see Pic. 9). The initial water temperature is 68°C. Before being used in pools,

these waters are mixed with cooler waters. The first well discharges 300 m3/d whereas the flow rate of

the second well is about 2200 m3/d. According to investigations by the Hungarian health

administration, the second well discharges cure waters.

The central water work of Eger covers 40% of the common water consumption of the city. This is

about 16 700 m3 per day (see Fig. 10, way point 21). Today, the water work is about 80 years old. It

was founded with a 60 metres deep drilling in the 20-ies of the last century. It was an artesian spring.

The pumped waters were captured in Eocene limestone horst (Fig. 11). Isotopic measurements have

shown that the water is less than 7000 year old. Some meters far away, there is a swimming pool. In

one part of the pool bottom, gravel filters the arising water (Pic. 10) whereas adjacent floors are out of

concrete. The main risk in the Eger region deals with interaction of Karst waters and stream waters

which would impair the quality of drinking and cure waters. But by now, Karst waters only discharge

in the river. Any riverine input in Karst ground-water was excluded.

Next-door, there is the turkey spa. It was built in the 14th century and it represents the first appointment

where thermal waters were used. This water degasses radon and carbon dioxide which is said to help

in medical purposes.

Another known spring is Saint Jozefs (see Pic. 11.). It consist of major calcium with 94mg/L and less,

manganese, sodium and potassium in decreasing content. The anionic composition records major

amount of hydrocarbon, less sulphate and sparse chloride.

Conclusion The studied geothermal resources in the Czech Republic and Hungary are exclusively used for

balneologic and touristy purposes. In recent times, geothermal concepts dealing with energy


9

generation are of minor importance. But increased demand on environmentally-compatible

technologies will lead to progress in geothermal use then. By fact, there are already incipiencies on

new geothermal thinking and usability.

Main differences between Czech und Hungarian thermal waters result from derivation depth,

temperature and dimension of use. The Hungarian water temperatures are mostly higher than the

Czech ones. This results from geological setting and depth. The Hungarian waters are warmed by

general high-standing mantle which causes the high geothermal gradient and water temperature. In the

Czech Republic, the high water temperatures result from mantle pluming. This is defined as regionally

restricted bulging of the mantle. Furthermore, isotope analyzes point to water derivation from different

depth. In the Bükk mountains, the waters are particularly of meteoric origin whereas, the Czech waters

are composed of juvenile waters derived from meteoric waters and the mantle. Studied helium-

isotopes point to gas origin in the mantle. In Hungary, thermal waters are commonly used for touristy

attraction. Therefore, spas are the most popular concept. In contrast, the Czech waters are exclusively

used for balneologic and cure purposes.

Terms Mofette is a subaeric spring where cold subsurface and volcanic gases are discharged. The vapour

predominantly consists of Carbon dioxide but also of methane and hydrogen sulphide. Traces of the

inert gases (e.g. helium) may be abundant too.

Fumarole is a subaeric spring where thermal waters and volcanic gases are discharged. The vapour

predominantly consists of carbondioxid but also of methane and hydrogen sulphide.


10

References BALOGH, K (1964) A Bükkhegység földtani képzödményei (Geologic formations of the Bükk

mountains). MAFI Evk, v. 48/2, p. 245-719.

BRÄUER, K., KÄMPF, H., STRAUCH, G. and WEISE, S.M. (2003) Isotopic evidence (He/He, CCO2)

of fluid-triggered intraplate seismicity. Journal of Geophysical Research, Vol. 108 (B2), p. 2070,

doi:10.1029/2002JB002010.

BURCHARDT, S., KRUMBHOLZ, M., FRIESE, N. and GUDMUNDSSON, A. (2005) Natürliche

geothermische Reservoire in Island: Bedeutung für künstliche geothermische Rservoire in

Deutschland. IN: Geothermische Vereinigung e.V. (eds) Geothermie: Synergie und Effizienz.

Geothermische Jahrestagung 2005, p. 161-162.

ELDER, J. (1981) Geothermal system. Academic Press London, p. 161.

GENTER, A., GUILLOU-FROTTIER, L., FEYBESSE, J-L., NICOL, N., DEZAYES, C. and

SCHWARTZ, S. (2003) Typology of potential Hot Fractured Rock resources in Europe.

Geothermics, Vol. 32, p. 701-710.

HAAS, J., KOVACS, S., KRYSTYN, L. And LEIN, R. (1995) Significance of Late Permian-Triassic

facies zones in terrane reconstructions in the Alpine-North Pannonian domain. Tectonophysics, v.

242, p. 19-40.

HURTER, S. and SCHELLSCHMIDT, R. (2003) Atlas of geothermal resources in Europe.

Geothermics, Vol. 32, p. 779-787.

KACURA, G., FRANKO, O., GAZDA, S. and SILAR, J (1969) Thermal and Mineral Waters of

Czechoslovakia” IN: G. Kakura and J. Jetel (eds) Report of the Twenty-Third Session

Czechoslovakia, International Geological Congress, Academia, Prague, p. 17-29.

MEINHOLD, R. (1984) Energie aus der Tiefe der Erde. 2. Auflage. Teubner Verlagsgesellshaft, p. 46-

61.

NEMETH, N. and MADAI, F. (2005) Early phase ductile deformation elements in the limestone of

the eastern part of the Bükk mountains. Acta Geologica Hungarica, v. 48/3, p. 283-297.

PASCHEN, H., OERTEL, D. and GRÜNWALD, R. (2003) Möglichkeiten geothermischer

Stromerzeugung in Deutschland. Arbeitsbericht 84, TAB, Büro für Technikfolgen – Abschätzung

beim Deutschen Bundestag.

SANNER, B. (2005) Synergie nutzen – Geothermie in Kombination mit anderen Erneuerbaren (und

sonstigen) Energien. IN: Geothermische Vereinigung e.V. (eds) Geothermie: Synergie und

Effizienz. Geothermische Jahrestagung 2005, p. 27-38.

TRUNKO, L. (1996) Geology of Hungary. Beiträge zur regionalen Geologie der Erde. Gebrüder

Bornträger, p. 401-404.

TRUNKO, L. (1961) Geologie von Ungarn. Beiträge zur regionalen Geologie der Erde. p. 13-16, 67-

74.


11

WALTER, R. (1995) Geologie von Mitteleuropa. Schweizerbartsch’sche Verlagsbuchhandlung,

Stuttgart. p.

WORLD WIDE WEB:

1* Helmholtz - Centre for environmental research UFZ:

http://www.ufz.de/index.php?de=6141

2* Helmholtz - Germany's National Research Centre for Geosciences GFZ:

http://www.geo.tu-freiberg.de/hydro/vorl_portal/HydroEx/bublak_mofette.pdf

3* TU Freiberg – Geothermie:

http://www.geo.tu-freiberg.de/hydro/vorl_portal/environ_geol/geothermie.html

4* Concepts in geothermal energy

www.geothermie.ch

International heat flow commission:

http://www.heatflow.und.edu/czech.jpg

http://www.heatflow.und.edu/europe.jpg

http://www.heatflow.und.edu/germany.jpg

http://www.heatflow.und.edu/japan.jpg


12

Appendix

Figures

Fig.1. Map of middle Europe including way points. Green points: geothermal-related springs/ spas, red

points: Moravian Karst, Danube and water distribution Miskolc and Eger

Fig. 2. Geothermal heat flow in Europe


13

Fig. 3. Geothermal heat flow in Czech Republic (for units see Fig. 1.)

Fig. 4. Geothermal heat flow in Hungary (for units see Fig. 1.)


14

Fig. 5. Geological map of northwestern Czech Republic


15

Fig.6. Detail map of northwestern Czech Republic including road points of geothermal

investigation. Green points: geothermal springs/ spas

Fig.7. Areal distribution of Soos spring waters related to their hydrogeochemical composition


16

Fig. 8. Model of spring water generation

Fig. 9. Geotectonic sketch of Hungary focussing on Bükk mountains (Pelso unit), Lined areas:

Restricted basin carbonates


17

Fig.9. Detail map of north-eastern Hungary and the road points of geothermal investigation. Green

points: geothermal springs/ spas, red points: water distribution Miskolc and Eger

Fig. 10. Geological cross-section of Bükk limestone horst showing water migration paths.


18

Pictures

Pic.1. Topographic view on Eger basin and Tertiary volcanic remnants at Nové

Mesto – skistation Bourrnak

Pic.2 Replaced church in Most


19

Pic. 3. Conical Relicts of Tertiary volcanism in the Eger basin

Pic. 4. Articfical thermal spring in Karlovy Vary


20

Pic. 5. Degassing at Soos mofettes

Pic. 6. “Kaiserquelle” enriched in iron at Soos springs


21

Pic. 7. Degassing of cold spring waters at Bublak

Pic.8. Water treatment in Yori spa


22

Pic. 9. Egerszaloki Spa under construction and natural sinter precipitation

Pic. 10. Gravel filter in Eger swimming-pool in Eger


23

Pic. 11. Saint Josefz spring in Eger

report geothermal resources - TU Bergakademie Freiberg · Geothermal resources 2 The high...

Documents

Transcript of report geothermal resources - TU Bergakademie Freiberg · Geothermal resources 2 The high...