TRANSENERGY - Transboundary Geothermal Energy Resources of Slovenia, Austria, Hungary and Slovakia

Geographical -geological setting

Launch event, May 27, 2010, Geologische Bundesanstalt, Neulinggasse 38, 1030 Wien

Radovan Černák, Balazs KronomeGeological Institute of Dionyz Stur, Bratislava, Slovakia

• Basic overview of the geographical and geological set-up of the area

• Brief description of the geotectonic evolution

• Simplified overview on the geological, lithological content of the geothermal structures

Introduction

Geographical setup Mountain ranges

Basins and planes

Alps

Transdanubian range

Carpathians

Vienna basin

Danube basin

Styria basin

Mura - Zala basin

The Transenergy region - diverse landscape

Geological setup

Paleozoic and older complexes – granitoides, metamorfic rocks,sedimentary formations

Mesozoic rocks – limestones, dolomites, conglomerates, claystones

Paleogene sediments – sandstones, conglomerates, claystones

Neogene sediments – sandstones,conglomerates, claystones

Neogene volcanic rocks

Quaternary sediments

Geological map of Europe 1: 10 million

Project -OneGeology

Colors represent geological formation

Colors – diverse geological environment –complicated geological structure and origin

Mesozoic sedimentation mainly in sea environment (250 Ma to 65 Ma)

Sedimentation on pre-Mesozoic basement (crystalline rocks, paleozoic units)

Sedimentation - couple of 100s of meters - limestones, dolomites, conglomerates and claystones

Alps and Carpathians have similar lithological content, because of sedimentation in the same environment

Result orogenesis, creating fold and nappe stucture

Nappe stacking – repetition of the similar sequenses on top of each other

Note: these Mesozoic nappe structures are important for the later geothermal structures

During Cretaceous convergence and S-N : pressure and closing of the basins sedimentation

Change in sedimentation (start of new „era“)

Geological evolution of Alps and Carpathians very similar in pre-Mesozoic and Mesozoic era

Geotectonic evolution of the area

Horváth et al. 2004

Geotectonic evolution of the area

ALCAPA (the easternmost part of the Alpine system) plate escapes to the area of Silesian-Moldavian basin

Complicated by collision and rotation of the micro plates (Alcapa and Tisza-Dacia)

Starting from Miocene (cca 20 Ma) the tectonic of the Alps and Carpathians starts different story

Horváth et al. 2004

Complicated evolution more processes of different nature happen in the same time:- subduction on the margins (progressing eastward)- volcanism (progressing eastward) – strongly connected to subduction- in the hinterland opening of the basins – thinning of the crust (mantle upwelling)

Geotectonic evolution of the area

– lithospheric plate becoming thinner resulting in higher heat flow

– creation of the basins

Important for geothermal structures

– presence of the fault lines and fault zones

Depth of the pre-neogene basement

Recent tectonic picture shows - elevated areas (mountains) - subsided areas (basins)

Depth of the Pre-tertiary basement

Vienna Basin Geological map with the surface geological formations

Vienna BasinSlovak part

Pull apart type of the basin

Pre tertiary basement:Mesozoic carbonates Central West Carpathians

and Northern Calcareous AlpsPaleogene flysch – sandstones/claystonesNeogene fill – sandstones, conglomerates, claystones

Kováč, 2000

Kováč, 2000

Vienna BasinAustrian part

Danube Basin

Pannonian lake sedimentsMiocene sea sediments Triassic carbonates (limestones, dolomites)

Older paleozoic complexesCrystalline basement

Danube Basin

Pretertiary basement –paleozoic krystaline rocks, Mesozoic carbontes

Quaternary fill – sands gravel

Neogene –sandstones, vulcanoclastics,conglomerates,claystones

Juhász, 1994

Kováč, 2000

Komarno - Sturovo area

Neogene sediments

Mesozoic sediments

Neogene vulcanic formations

Komarno - Sturovo area

Geological built of the area --Slovak part – Palegene and Neogene fill of the basin-On the Crystralline and Mesozoic basement

Mesozoic carbonates

-Hungarian part - Mesozoic structures outcroping on the surface in mountains Gerecse and Pilis-on the top Palegene and Neogene sediments- Neogene vulcanic rocks present

Paleogene sediments

Neogene sediments

Crystralline basement

Important – circulation of geothermal water in mesozoic carbonates

Cretatious sediments

Pre-tertiary basementStyria Basin

Upper Austroalpinenappes

Neogene sediments – breccias, gravels, sands

Styria Basin andMura Zala Basin

Styrian Basin

Neogene sediments –marl, clays, sands, conglomerate

Ljutomer Budafa tectonic half -trench

Neogene sediments –clays, sands, gravel intercalations

Radgona –Vas tectonic half-trench

Mezozoic carbonates

Conclusion

The area of investigation in TRANSENERGY region is, from geological point of view, very complicated.

Though we have good information to have an idea about the geological history and built of the area.

Need for harmonizing of geological information.

Work to be done and outputs

• Make an inventory of existing works – geological maps on national, international level, interpreted geological cross sections, relevant publications and reports;

• Unify terminology, lithostratigraphical units, geological and tectonic interpretations;

• Create geological maps, cross sections;

• Create simplified geological models of the structures, that will show the basic geometry of the geothermal systems.