geo-resources and geo-hazards · andreas hoppe served as chief-editor of the “zeitschrift der...

Annual Report 2012, Faculty of Materials- and Geo-Sciences, Technische Universität Darmstadt

Institute of Applied Geosciences – Geo-Resources & Geo-Hazards 1

Geo-Resources and Geo-Hazards In times of rapid population growth and the resulting strain of the resilience of natural systems, geosciences in particular have become an increasingly important research area. However, geoscientific knowledge about material flows from and back into the environment and about the prevention of catastrophic consequences of big natural phenomena is often not understood by decision makers, who were not able to spend long years on understanding the four-dimensional space-time-development of our earth. On the other hand, the metabolism of cities, its growing needs for clean water and raw material for constructions while simultaneously egesting waste into its neigh-bourhood, require a thorough understanding of its undergrounds and peripheries as well as safe construction sites. Computer based Geo Information Systems and 3 to 4D-techniques are powerful tools to qualify and to quantify resources and hazards in the peripheries of urban areas. They enable the aggregation of complex geological and spatial data to thematic maps for a better understanding and interpretation by local decision makers. Staff Members Head Prof. Dr. Andreas Hoppe Research Associates Dipl.-Geoökol. Monika Hofmann Dr. Rouwen Lehné Dipl.-Geol. Ina Lewin Technical Personnel Dipl.-Kartogr. (FH) Ulrike Simons Holger Scheibner Secretaries Pia Cazzonelli PhD students Dipl.-Ing. Dirk Arndt Hannah Budde (MSc Geowiss.) Dipl.-Geogr. Constanze Bückner Dipl.-Geol. Marie Luise Mayer Students Filipe Lopes Chaves (BSc Belo Horizonte), Marie Mohr

(BSc), Bastian Neef (BSc), Obinna Nzekwe (MSc), Steven Owuor (MSc), Narmada Rathnayake (MSc), Nicole Schmuck (BSc Frankfurt a.M.)

Student apprentices Alexandra Knicker (Iowa State Univ., 8 weeks), John Wall (North Carolina State Univ., 4 weeks) Guest Scientist Prof. Dr. Prem B. Thapa (Georg Forster Research Fellow, Alexander von Humboldt Foundation)



Research Projects Constanze Bückner and Andreas Hoppe reported their first results within an interdis-ciplinary project about the “Intrinsic Logic of Cities” (funded by a Hessian initiative for excellence, LOEWE program) in a book comparing the cities of Mainz and Wiesba-den. Constanze Bückner won with an essay about „City and Countryside – Two Envi-ronments“ 2nd price in a competition „The Future World“ offered by the German Min-istry of Science (BMBF) together with the newspaper “Die Welt”. Prem Thapa from Tribhuvan University of Nepal continued with modelling of mass movements, wrote books about “Geo-informatics/-modelling” and “Landslide and De-bris Flow Hazard” and supervised two MSc theses dealing with landslide hazards in Nepal. Rouwen Lehné developed in cooperation with the Hessian Geological Survey (HLUG) a GIS and gOcad based 3D model of the Quaternary in the northern Upper Rhine Gra-ben. Outcomes of the ongoing project have been presented at several national and in-ternational conferences. He served as speaker of the Section Geoinformatics within the German Geological Society (DGG), has been re-elected for another 2 years and chaired a scientific session during the annual meeting of the DGG in Hannover. Fur-thermore he settled a co-operation with the Estonian Land Board in order to realize the first gOcad based geological 3D model for the northeastern part of the country by the use of well information, especially to deepen understanding of distribution and quality of resources (i.e. oil shale and black shale) as well as the shape of the pre Quaternary surface. Hannah Budde joined the group in autumn. In the frame of a cooperation with the HLUG she will elaborate a computer based 3D-visualisation especially of the Tertiary and Quaternary units of the “Lower Main Plain”, the area south of the Rhenish Massif which covers huge parts of the metropolitan region Rhein-Main. Hannah Budde has been elected to the board of the section Geoinformatics of the DGG. Ina Lewin analysed the specific sedimentary conditions for a small area in the Neo-gene Hanau-Seligenstadt Basin between the Odenwald and Spessart Mts three-dimen-sionally (gOcad) and estimated the groundwater flow with the help of a tracer test in cooperation with the “Zweckverband Gruppenwasserwerk Dieburg”. Dirk Arndt finished a goCad based geological 3D model of the Federal State of Hesse in an approx. 1:300.000 scale and successfully defended it as a doctoral-thesis (http://tuprints.ulb.tu-darmstadt.de/3082/). The evaluation of geopotentials in the surroundings of the fast growing capital of Mi-nas Gerais (Brazil) by Monika Hofmann led to a first draft of her doctoral thesis. Andreas Hoppe, Rouwen Lehné and Ulrike Simons continued in cooperation with the German Archeological Institute (DAI) the investigations about Olympia (Greece) to decipher the Holocene evolution of landscape and presented the first results in a mul-timedia presentation within an exhibition of the DAI “Mythos Olympia” in Martin-Gro-pius-Bau in Berlin (which will move to Athens and Doha in 2013). Andreas Hoppe served as chief-editor of the “Zeitschrift der Deutschen Gesellschaft für Geowissenschaften” (German Journal of Geosciences). As speaker of the Evenarí



Forum for German-Jewish Studies at Technische Universität Darmstadt he guided an interdisciplinary group of students to an excursion to Israel and the Occupied Territo-ries under the topic of “water within natural and cultural development and politics”, and he organized for the winter term 2012/2013 a series of interdisciplinary lectures on “Catastrophes”. In Bologna, he was chairman of a “Urban Geology” session during an international meeting about Geo Information Systems. Publications Bückner, C. & Hoppe, A. (2012): Kartierte Städte – Mainz und Wiesbaden im Span-

nungsfeld von Naturraum und Vergesellschaftung. - 226 S., Frankfurt/M. (Campus) [ISBN 978-3-593-39573-9].

Hoppe, A., Lehné, R., Hecht, S. & Vött, A. (2012): Olympia im Kontext der jüngsten Erd- und Landschaftsgeschichte. – In Heilmeyer, W.-D., Klatsas, N., Gehrke, H.-J., Hatzi, G.E. & Bocher, S., Mythos Olympia – Kult und Spiele, 232-235, München (Prestel) [ISBN 978-3-7913-5212-1].

Lamelas, M.T., Marinoni, O., de la Riva, J. & Hoppe, A. (2012): Comparison of multicrite-ria analysis techniques for environmental decision making on industrial location. – In Chiang Jao (ed.), Decision Support Systems, 15 pp., Rijeka-Shanghai-New York (Intech) [ISBN 978-953-51-0799-6] doi 10.5772/51222.

Lang, S. & Seidenschwann, G. (2012): Die pliozäne Entwicklung der Hanau-Seligenstäd-ter Senke, des Kinziggebietes und des Vorspessarts. – Jber. Wett. Ges. ges. Natur-kunde 165: 79-132, Hanau.

Schumann, A., Arndt, D., Wiatr, T., Götz, A.E. & Hoppe, A. (2012): Extraction manage-ment optimisation with TLS and 3D modelling / Optimierung des Abraummanage-ments mit TLS und 3D-Modellierung. – ZKG International (Zement Kalk Gips) 7: 47-53, Gütersloh.

Thapa, P.B. (2012): Geo-informatics/-modelling - “Landslide Hazard and Risk”. Mahesh Printing Publisher, First Edition, Kathmandu, Nepal, 147 p [ISBN 978-9937-2-5348-2].

Thapa, P.B. (2012): Landslide and Debris Flow Hazard - “Modelling/simulation & miti-gation”. ST Publisher, First Edition, Kathmandu, Nepal, 163 p [ISBN 978-9937-2-5544-8].

Thapa, P.B. & Hoppe, A. (2012): 3D modeling of geological features. – Bulletin of Nepal Geological Society 29: 67-72, Kathmandu, Nepal.



Sonnenenergie aus Baggerseen im Ballungsraum Rhein-Main-Neckar?

Andreas Hoppe1, Alexandra Knicker2, Rouwen Lehné1, Christian Lerch3 & Marie Mohr1 1Inst. Angew. Geowiss. TU Darmstadt, 2Iowa State University, 3Viernheim

Mit der „Energiewende“ in der Bundesrepublik Deutschland, ausgelöst durch ein Erd-

beben in Japan am 11.3.2011 und dadurch ausgelösten Folgekatastrophen (Tsunami,

Kernschmelzen im Atomkraftwerk Fukushima) stieg und steigt immer noch die Nach-

frage nach „alternativer Energie“. Dazu gibt es bereits Ideen und auch schon Umset-

zungen von Großprojekten wie „Desertec“ (zur Gewinnung von Solarstrom in sonnen-

reichen Wüsten) und Windanlagen in der Nordsee. Diese Ansätze erfordern jedoch

lange Transportstrecken für den produzierten Strom bis zum Kunden und „verbrau-

chen“ dabei neben Investitionsmitteln auch große Flächen für die notwendigen

Infrastrukturen. Dezentrale Stromgewinnung nahe am Verbraucher wäre die ökono-

misch und ökologisch günstigere Lösung, zumal wenn sie aus regenerativen Energie-

quellen käme und zudem zu „intelligenten Netzen“ der Stromgewinnung und Speiche

rung verknüpft würde und außerdem eine „Wertschöpfung vor Ort“ ermöglichen

könnte.

Für den Ballungsraum Rhein-Main-Neckar, einem der finanzstärksten Räume Europas,

bietet das geologische Senkungsgebiet des Oberrheingrabens sehr günstige natur-

räumliche Voraussetzungen: Es befriedigt u.a. den Bedarf an Grundwasser und Mas-

senrohstoffen und erlaubt hohe landwirtschaftliche Erträge. Allerdings ist das Gebiet

inzwischen zu einem großen Teil mit Siedlungen und Verkehrsinfrastruktur versiegelt

(Abb. 1) und Flächennutzungskonflikte nehmen zu. Fläche ist also knapp. Wir haben

daher einen Gedanken bayerischer Kollegen (Gillhuber & Poschlod, 7th Euregeo 2012:

566-7, Bologna) aufgenommen, die in aufgelassenen Kiesgruben und Steinbrüchen

nutzbare Flächen für die Energiegewinnung sehen.

Flächen für die Gewinnung oberflächennaher Rohstoffe werden von Vielen vor einer

Abbaubewilligung heftig verteidigt und als „Flächenverbrauch“ gewertet, während

nach einem erfolgten Abbau von Sand und Kies der dann offen liegende Grundwasser-

spiegel oder Baggersee von wiederum Vielen als „Flächengewinn“ für die Freizeitge-

staltung oder den Naturschutz betrachtet wird. Angesichts des Rohstoffhungers unse-

rer Gesellschaft sind es im nördlichen Oberrheingraben inzwischen große Flächen,

deren potenzielle Nutzung für Solaranlagen also untersucht werden sollte. Dazu haben



wir die Möglichkeiten Geographischer Informationssysteme (GIS) genutzt und die

potenziellen Wasserflächen betrachtet:

Abb. 1: Die nördliche Oberrheinebene (rechts mit Blick auf den Melibokus) ist bereits

zu fast einem Viertel mit Siedlungen und Gewerbeflächen (rot) sowie Verkehrswegen

überbaut. Die restliche Fläche wird intensiv für landwirtschaftliche Sonderkulturen,

den Abbau von Sand und Kies, die Gewinnung von Grundwasser und geothermischer

Energie sowie den Naturschutz und Freizeitaktivitäten genutzt.

Dabei zeigt sich, dass theoretisch eine Wasserfläche von etwa 45.000.000 Quadratme-

tern bzw. gut 4.500 Hektar zu Verfügung stünde. Geht man davon aus, dass eine Solar-

zelle pro Quadratmeter derzeit maximal 108 Watt pro Stunde erzeugen kann und dass

die mittlere Sonnenscheindauer zwischen Karlsruhe und Frankfurt bei etwa 1.840

Stunden pro Jahr liegt, so ließe sich eine theoretische Ausbeute von mehr als 10 Millio-

nen Kilowattstunden pro Jahr abschätzen (108 W/h x 45.000.000 m2 / 1 m2 x 1840 h/a =

8.942.400.000 kWh/a). Setzt man dies ins Verhältnis zu dem von der Weltbank 2009 für

Deutschland angegebenen durchschnittlichen Jahresverbrauch von 6.779 Kilowattstun-

den pro Person, so ließe sich damit theoretisch der Energiebedarf von mehr als 1,3

Millionen Menschen oder der doppelten Einwohnerzahl von Frankfurt a.M. befriedi-

gen.

Selbstverständlich sind dies rein theoretische Überschlagsrechnungen: Die Wasser-

fläche ließe sich nicht zu 100% nutzen, da andere Nutzungsansprüche dem entgegen-

stehen, und sicher käme die Energieausbeute in dem geschätzten Umfang nicht ohne

Verluste beim Verbraucher an. Andererseits scheinen selbst bei einer Nutzung von nur



einem Drittel der Wasserfläche in der Oberrheinebene erhebliche Energieausbeuten

möglich.

Schwimmende Solaranlagen auf Baggerseen ließen sich in ihrer Ausrichtung einfach

dem täglichen Sonnengang anpassen. Die durch die Abdunkelung der Wasserfläche

entstehenden unterschiedlichen Temperaturen an der Wasseroberfläche würden

vermutlich außerdem eine Zirkulation im Wasserkörper in Gang setzen, die zur Sauer-

stoffanreicherung führen könnte.

Ein Problem von Solaranlagen ist der nicht immer kongruente Zeitraum von Stromge-

winnung und -verbrauch. Neben den hier nicht diskutierten technischen Möglichkeiten

zur Speicherung von Solarenergie sei auf die Vorteile des Naturraumes für den nördli-

chen Oberrheingraben zumindest hingewiesen: die mögliche Nutzung von Wasser-

speichern. Dazu bietet sich das Rheinische Schiefergebirge am Nordrand des Bal-

lungsraumes an. Die geologischen Voraussetzungen sind hier günstig, und ausgearbei-

tete Pläne für eine Talsperre liegen vor – etwa seit den 1980er Jahren für das nur we-

nige Kilometer westlich von Mainz und Wiesbaden gelegene Ernstbachtal.



What buried Olympia?

Andreas Hoppe, Rouwen Lehné, Marie Mohr & Ulrike Simons

Institute of Applied Geosciences, Technische Universität Darmstadt

In ancient Greece, in the Holy District of Altis (see the descriptions of the Greek histo-

rian Pausanias, written in 2nd century BC; cf. Sinn 2004, Heilmeyer et al. 2012), men met

every four years at Olympia for the ancient Olympic tournaments. It is a place at the

confluence of two rivers: the turbulent Alpheios and the Kladeos (a tributary of the Al-

pheios). Receiving its waters from a large catchment area, the Alpheios is 110 km long

and the main river of the northern Peloponnese.

Fig. 1: The north-western part of the Peloponnese, with the Alpheios as the main river,

is an active neotectonic-seismic area due to (see inset) eastward subduction along the

Hellenian Arc against a movement of the Anatolian Plate to the west which results in a

north-south dilatation of the Gulf of Corinth.

But why was it necessary to excavate this area, done systematically since the 19th cen-

tury, after it was rediscovered a century earlier? It was previously hidden under a con-

ical alluvial fan of the Kladeos, the so called Olympia Terrace (Fig. 2), comprising

mainly of silty sediments up to 6 m thick. Now, the top of the flat lying terrace, in the

bed of the Alpheios south of Olympia, is approx. 33 m above sea-level with sharp



ridges up to 7 m high in some places. A narrow valley, between 8 and 10 m deep, was

incised through the Olympia Terrace by the Kladeos.

Fig. 2: Recent extent of the Olympia Terrace (yellow) around Olympia (left). Catchment

area for the Kladeos (right) composed of marine Pliocene (dark yellow), younger Plio-

cene continental sediments (green), Pleistocene conglomerates (light brown) and the

Holocene Olympia Terrace (yellow) which was later incised and filled by alluvial de-

posits of the Kladeos (dark brown).

Hypotheses to explain the burial of Olympia are manifold (cf. Hoppe et al. 2012): (i)

flooding by episodic outburst of karst lakes in the higher hinterland of the Alpheios, (ii)

settlement of the area and the resulting changes in land use (e.g. deforestation) that

caused higher rates of soil erosion, (iii) climatic fluctuation with phases of higher pre-

cipitation and soil erosion and (iv) earthquakes in 521 and 551 BC that destroyed

Olympia and resulted in flooding and sedimentation of the Altis. However, as of yet,

there is no evidence to support the theories of higher erosion induced by land use

changes or climatic change. Nor may episodic flooding alone explain a thick alluvial

cone of the Kladeos.

Recent investigations by a joint group from Darmstadt and Mainz Universities (Vött et

al. 2010) generated a fifth hypothesis: a tsunamigenic origin of the burial of Olympia,

which is supported by the presence of marine gastropods found in drill cores from the

Olympia Terrace. Thus, Vött el al. (2012) postulate that a tsunami wave, which followed

the wide valley of the lower Alpheios, passed through a morphologic saddle north of

Olympia (labelled “Pass” in Fig. 2a) at an altitude of more than 60 m and then ran down



the Kladeos bed, bringing with it the observed marine fauna as well as the sediments

hiding the Altis.

However, a Kladeos cone generated by a tsunami seems unlikely because it would

have required a runup of almost 20 km inland with a height of 60 m above sea level as

well as large amounts of sediment to cover the ancient Olympia. As is known from re-

cent observations, the top of a tsunami consists in the majority of water (cf. Bahlburg &

Spiske 2012). So, even if autochthonous marine sediments were mobilized by a tsunami

running down the valley of the Kladeos, the thick sedimentary pile hiding the Altis

cannot be explained by the small catchment area that lies between the “pass” and

Olympia (Fig. 2b).

A more likely interpretation, which combines existing information on the regional ge-

ology (Streif & IGME 1982) and geomorphology, new field investigations (drilling,

dating, component and grain size analysis) and geomorphological analysis using IKO-

NOS-data (1x1 m resolution) as well as a digital elevation model (based on topographic

maps 1:5,000 and 1:50,000) is:

The surroundings of Olympia are composed mainly of fine grained marine sediments

of the Pliocene age which are overlain by younger continental sediments including

Pleistocene conglomerates which form, on the east and west of Olympia, a hard ridge

or a barrier for the Alpheios 6 km west of Olympia. This can be seen by a sudden

northward bend of the river (Fig. 2). The estimated volume of the Holocene Olympia

Terrace, calculated using a GIS-based analysis, is approx. 15,000,000 m3. The catch-

ment area of the Kladeos is almost 33 km2.

The accumulation of the Kladeos cone and the Olympia Terrace respectively is as-

sumed to have begun in ancient Greece due to the presence of a man-made wall west

of the Altis. This wall was very likely built to avoid flooding of the Holy District by the

Kladeos (cf. Heilmeyer et al. 2012). The rising levels of the Kladeos, accompanied by

sedimentation, continued for several centuries. This is indicated by remnants of or-

ganic material found 2.35 m below the today´s surface which, when dated, revealed a 14C age of 1875±30 years.

The blocking of the Alpheios west of Olympia with sediments was likely due to an epi-

sodic flood or mass movement (whether triggered by earthquake and/or heavy preci-

pitation is not known). This in turn lowered the transport energy of the Alpheios east of

the bottleneck, as water levels rose, which then affected the Kladeos, so that the



Kladeos suddenly lost gradient leading to deposition of eroded sediment from its up-

per catchment area. It is known from the classical diagram of Hjulstrom (1935) that

flow speed and grain size determine whether a particle is eroded, transported or de-

posited.

Evidence indicates that during the Plio-/Pleistocene times fine grained marine sedi-

ments were washed through the Kladeos and Alpheios valleys into the Mediterranean.

The blocking of the Alpheios bottleneck, west of Olympia in historical times, reduced

the flow speed of the Kladeos which then led to the deposition of eroded sediments

from upstream thus burying the Altis. Some marine fauna from Pliocene sediments was

obviously included. Opening of the bottleneck, post-Roman times, allowed a “normal”

discharge of the rivers, and the now more rapidly moving waters of the Kladeos in-

cised into its own alluvial fan. Similarly, the rapidly moving waters of the Alpheios

eroded the Olympia Terrace leaving steep and high cliffs south of the Altis.

Very likely (and unfortunately) this recent erosion has taken away remnants of the

Hippodrome as well – the antique place for horse races which has been described in

detail by Pausanias. It is believed that it was situated east of the Altis which is now the

bed of the young, eroding and anastomosing Alpheios.

Acknowledgements: We cordially thank the Deutsches Archäologisches Institut with Hans-Joachim

Gehrke and Reinhard Senff as well as Andreas Vött from Universität Mainz for manifold support in

Olympia.

References: Bahlburg & Spiske, M. (2012): Sedimentology of tsunami inflow and backflow deposits: key

differences revealed in a modern example. – Sedimentology 59: 1063-1086. * Heilmeyer, W.-D., Klatsas,

N., Gehrke, H.-J., Hatzi, G.E. & Bocher, S., Hg. (2012): Mythos Olympia – Kult und Spiele. – 594 pp., Mün-

chen (Prestel) * Hoppe, A., Lehné, R., Hecht, S. & Vött, A. (2012): Olympia im Kontext der jüngsten Erd-

und Landschaftsgeschichte. – In Heilmeyer, W.-D., Klatsas, N., Gehrke, H.-J., Hatzi, G.E. & Bocher, S.,

Mythos Olympia – Kult und Spiele, 232-235, München (Prestel) * Hjulstrom, F. (1935): The morphological

activity of rivers as illustrated by River Fyris. – Bull. Geol. Inst. Uppsala 25: 221-527. * Sinn, U. (2012): Das

antike Olympia – Götter, Spiel und Kunst. – 276 pp., München (Beck). * Streif, H. & Institute of Geology &

Mineral Exploration (1982): Geological Map of Olympia 1:50.000, Athens. * Vött, A., Bareth, G., Brückner,

H., Fountoulis, I., Gehrke, H.-J., Hoppe, A., Lang, F., Lehné, R., Sakellariou. D. (2010): Beachrock-type

deposits document tsunamigenic destruction of Olympia's ancient harbour (Greece). – Schriftenr. Dt.

Ges. Geowiss. 68 (GeoDarmstadt2010): 574-575, Stuttgart. * Vött, A., Fischer, P., Hadler, H., Handl, M.,

Henning, P., Lang, F., Ntageretzis, K., Röbke, B. & Willershäuser, T. (2012): Testing the Olympia Tsunami

Hypothesis (OTH) – new results from tsunami modeling and palaeotsunami studies in the lower Alpheios

River valley (Peloponnese, Greece). – Program Deuqua 2012, 2 pp., Bayreuth.

geo-resources and geo-hazards · andreas hoppe served as chief-editor of the “zeitschrift der...

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