Department of Engineering Geology (TEGE)

Engineering Geology is a multidisciplinary branch of the geosciences that brings together geology and engineering. According to the definition of the International Association for Engineering Geology and the Environment (IAEG, 1992), engineering geology is the science that “deals with the investigation, study, and solution of technical and environmental problems that may arise from the interaction between geology and human works/activities, as well as the forecasting and development of measures to prevent or address geohazards.”

Today, the need for more comprehensive engineering-geological and geotechnical studies is more pressing than ever, due to the continuously increasing volume of construction and higher safety requirements. An additional modern imperative is the conservation and protection of the natural environment from human activities, as well as from the rising geohazards associated with climate change.

The impacts of natural disasters (landslides, earthquakes, floods, etc.) are critical for the preservation and safety of infrastructure and settlements. In Greece, numerous settlements have been relocated after being designated as landslide-affected. Natural disasters frequently damage infrastructure (roads, utilities, etc.), with significant economic and social consequences.

The Department of Engineering Geology of H.S.G.M.E.—reporting to the Directorate of General and Applied Geology (DIGEGE)—has specialized scientific staff to address these issues through a range of field and laboratory investigations. Over its long history, it has conducted numerous investigations and specialized studies and has formulated recommendations that support sound decision-making for managing geologically driven natural disasters and for the safe construction of major engineering works.

Engineering Geology as a research field has been covered by the Hellenic Geological Service (IGEY – ETHIGME – IGME – H.S.G.M.E.) since the 1950s. The activities of the Department of Engineering Geology can be summarized as follows:

Scope / Activities

The Department of Engineering Geology of H.S.G.M.E. carries out “Engineering-Geological & Geotechnical Investigations and Studies” to meet the needs of its research scope.

Investigation of Destructive Geological Phenomena

Mass movements

The investigation and study of mass-movement phenomena—mainly in residential areas and along the road network—is one of the core activities of the Department of Engineering Geology. From the founding of IGEY (1952) to the present, more than 5,000 mass-movement incidents have been investigated across Greece. Mass movements include all forms of displacement of soil or rock masses, in particular:

• Landslides of all types
• Rockfalls
• Subsidence
• Ground settlement

Within these investigations, both the dynamics and the triggering mechanisms are examined, while appropriate qualitative prevention or mitigation measures are proposed.

An important activity of TEGE in recent years has been delineation studies of areas already affected—or at risk (threatened)—by potential expansion of landslides in residential zones (e.g., the Municipalities of Zagora–Mouresi, Meteora, Pyli, Karpenisi, Platanias, etc.). Detailed delineation of affected areas is necessary for the issuance of Joint Ministerial Decisions (JMD) by DAEFK (General Directorate for the Rehabilitation of Natural Disaster Effects), which grant housing assistance to those affected for the repair of their buildings.

Seismogeological, macroseismic, and microzonation studies (in collaboration with other institutions)

Numerous macroseismic investigations have been carried out in earthquake-affected areas, and seismic hazard maps have been compiled. In the field of earthquake-disaster prevention, the Department participates in microzonation studies (e.g., Kozani, Konitsa, Anthoupoli–Peristeri, etc.). At the national level, the seismotectonic map of Greece at 1:500,000 scale has been produced.

 

Design Studies and Construction of Major Engineering Works such as:

Dams & reservoirs

Numerous investigations and studies have been completed to assess the geological, engineering-geological, and geotechnical factors that determine suitable locations for water-storage reservoirs (e.g., Ag. Dimitrios–Evinos Dam, Iasios–Komotini Dam, dams in Western Macedonia, etc.).

Natural Gas Pipeline

For the pipeline, engineering-geological and geotechnical reconnaissance and studies were conducted to determine foundation conditions and slope stability along the alignment of the Natural Gas Transmission Pipeline—on the main route and its branches—with a total length of approximately 1,200 km. During operation of the pipeline and its main branches, H.S.G.M.E. (IGME) provides consultancy services, participating in a rapid response team in the event of earthquakes or landslide occurrences.

Underground works and geotechnical studies for special structures

The engineering-geological conditions and geomechanical properties of soil and rock formations encountered at depths affecting the foundation are assessed to guide designers toward the most suitable construction and operational solutions (Evinos–Mornos tunnel, Ancient Dodoni bypass, etc.).

Geological Suitability for Urban Development

The engineering-geological conditions and geomechanical properties of soils and rocks at depths influencing foundation design are evaluated to assist engineers in selecting optimal solutions for construction and operation (cost–safety). H.S.G.M.E. (IGME) has carried out—and continues to carry out—a large number of such studies related to urban and town-plan expansions, as well as the re-designation of landslide-affected settlements.

Environmental Protection and Landscape Restoration Works

Participation in environmental protection projects through engineering-geological and geotechnical studies aimed at limiting environmental impacts from high-risk facilities such as landfills, cemeteries, and tailings ponds (e.g., Kozani Wastewater Treatment Plant, Salamina sewer pipeline, Rethymno landfill, etc.). Under the 3rd CSF, studies were prepared on methods for rehabilitating abandoned quarries and mines, with pilot applications in the regional units of Achaia, Drama, Ioannina, and Kozani.

Protection of Cultural Heritage Monuments

 

Within this framework, investigations and studies have been conducted on the stability conditions of foundations for historical and cultural monuments, as well as on identifying the causes that threaten structures and their surroundings, such as:

• Geological
• Geotechnical study of the Acropolis of Athens
• Geotechnical study of the area around the Temple of Apollo Epicurius
• Geotechnical studies on the historic walls of Heraklion, Rethymno, and Chania (Crete)
• Engineering-geological investigation of Platamon Castle
• Engineering-geological investigation of the Castle of Pythagoreion, Samos
• Geotechnical investigation of the METRO tunnel at Kerameikos
• Geotechnical studies of Venetian castles in Amfissa, Lemnos, and Corfu; of Byzantine churches in Western Macedonia and the Peloponnese; and of monuments in many other regions of Greece

 

Research Methodology

Engineering Geology projects include field and laboratory work, followed by data analysis/processing and the preparation of technical reports. Technical reports are delivered to the commissioning authorities, while copies are filed in H.S.G.M.E.’s Central Library and TEGE’s report archive; related databases are updated accordingly.

Field Work

1. Engineering-geological and geotechnical mapping

• Engineering-geological and geotechnical maps are compiled at various scales, depending on project needs and requirements. Representative examples include:
• The geotechnical map of Greece at 1:500,000 scale
• The engineering-geological map of central Rhodope at 1:50,000 scale
• Engineering-geological maps of urban areas at 1:10,000 scale (e.g., the former Prefecture of Athens area; the greater Thessaloniki area; and the cities of Grevena, Kastoria, Florina, Ptolemaida, Nafplio, Sparta, Drama, Volos, and Igoumenitsa)
• The engineering-geological map of the greater Kozani area at 1:5,000 scale, as part of a microzonation study

 

2. Geotechnical boreholes – trial pits – sampling

Geotechnical investigations include drilling geotechnical boreholes with in-situ testing and/or trial pits, along with appropriate sampling for laboratory determination of the physico-mechanical properties of the engineering-geological units composing the study area.

3. Inclinometer measurements

Inclinometer surveys are used to detect ground movements (sliding), determine the depth of their occurrence, and monitor their evolution. For field measurements, the Department of Engineering Geology at H.S.G.M.E. uses specialized SISGEO equipment for borehole inclinometry. Measurements are performed in accordance with ASTM D4622–86 (Reapproved 1993).

Office Work

• Processing of field and laboratory data
• Evaluation and analysis using appropriate software
• Preparation of technical reports with data, conclusions, and recommendations
• Archiving of materials
• Database updates

 

Operation of the Rapid Response Team

The Department of Engineering Geology is responsible for the Rapid Response Team (RRT), which is activated after severe landslides, major earthquakes, or other geologically driven natural disasters. RRT crews are deployed immediately to affected areas to assess hazard levels and event dynamics and to provide advisory guidance to the competent authorities for immediate response. In recent years, the Rapid Response Team of H.S.G.M.E. has also supported the needs of the General Secretariat for Civil Protection under a relevant Memorandum of Cooperation.

TEGE Project Categories

For Third Parties

• Engineering-geological and geotechnical investigations and studies (landslides, geological suitability, etc.)
• Delineation of landslide-affected settlements
• Consultancy services to local authorities, public bodies, organizations, or private clients

 

EU Co-funded Programs – 2nd CSF

• “Studies for utilizing surface waters with small dams” (Regional Operational Program of Western Macedonia)
• “Engineering-geological study of destructive phenomena in the central Rhodope mountain range” (ROP of Eastern Macedonia & Thrace) − 3rd CSF (in collaboration with other HAGME units)
• “Investigation of geotechnical data in Western Macedonia” (ROP Western Macedonia) ✓ “Selection of dam sites” (ROP Western Macedonia)
• “Underground works” (National Funding)
• Urban Geology (Sparta, Nafplio, Thrakomakedones, Drama)
• “Development of environmentally friendly techniques for the rehabilitation of abandoned public quarry sites and their by-products” (National Funding). ✓ “Innovative techniques for recording and utilizing waste from the mining/metallurgical industry and abandoned public mines – pilot applications” (National Funding). − NSRF (2007–2013) (in collaboration with other HAGME units)
• Showcasing the ancient marble quarries of Marathi, Paros, aiming to create a geopark (MEOPY PROJECT – SUB-PROJECT 6 – UNIT 3)
• Urban Geology (Volos, Igoumenitsa) − NSRF 2014–2020 (2023)
• Assessment of Landslide Susceptibility across Greece (OPYGEK PROJECT – SUB-PROJECT GEOKA – ACTION 1)
• Urban Geology (Lamia)

 

Competitive Programs

Participation in interdisciplinary European research programs and committees. Some of the projects in which TEGE has participated include Terrafirma, Nemisref, ICOMOS, Ingeoclouds, while it contributes to working groups of EuroGeoSurveys (Earth Observation - GeoHazards, Urban Geology).

International Collaborations

• Greek–British collaboration (2001–2003). Participants included scientists from H.S.G.M.E. (former IGME) (M. Stefouli, Emm. Apostolidis, and P. Skarpelis), EYDAP, and the University of Leicester (UK). Project title: “Study of landslides along aqueducts using remote sensing and Geographic Information Systems.”
• European Program “Enabling access to geological information in support of GMES – PanGeo” (2011–2014)

 

Public Investment Programs

• Destructive phenomena (supports the activity of the Rapid Response Team)
• Geotechnical Data of Greece: Spatial Framework – Visualization (launched in 2021)
• Procurement and adaptation of UAV equipment for engineering geology applications (launched in 2021)

 

TEGE Research Report Archive

• Covers the period from 1930 to the present
• Includes 3,077 technical reports through the end of 2020

 

Databases

Within the Department of Engineering Geology, the following databases are developed and maintained:

• Landslides: Data from analog reports are digitized and entered into a GIS-based database (continuously updated)
• Underground Works (completed under a 3rd CSF project)
• Geotechnical data of Greece (launched in 2021)

 

Within the Department of Engineering Geology (TEGE) of H.S.G.M.E. operates the Soil Mechanics – Rock Mechanics Laboratory.

For more information about the departments of the Directorate of General and Applied Geology (DIGEGE), visit:

Department of General Geology, Geological Mapping and Applications (GE.XA.E.)

Department of Applied Geophysics (TEG)