DEPARTMENT OF APPLIED GEOPHYSICS.
Geophysics is the science that applies the laws of physics to study the structure of the Earth’s crust—especially its near-surface layers—based on measurements of geophysical parameters and the application of fundamental physical principles. The goal of Applied Geophysics is to detect subsurface structures of economic or other interest. The Department of Applied Geophysics of H.S.G.M.E. belongs to the Directorate of General and Applied Geology (DIGEGE) and has the know-how and equipment needed to help address geoscientific problems related to the following areas:
1) Mineral Exploration:
- Detection and spatial assessment of mineral raw materials—metallic and non-metallic—using geophysical methods
- Design of drilling programs
2) Subsurface Structure and Geotechnical Issues:
- Stratigraphic imaging of the subsurface and determination of tectonic features
- Mapping the topography of the bedrock surface
- Detection and qualitative assessment of zones with contrasting geotechnical properties within competent ground (fault zones, landslides, tectonic disturbance, loosened ground)
- Detection and sizing of underground voids (sinkholes, cavities, karst features, galleries, etc.)
- Determination of thicknesses of deposits and weathered layers
- Estimation of dynamic elastic parameters (Young’s modulus, Poisson’s ratio) and P- and S-wave velocities (Vp, Vs)
3) Hydrogeological Investigation:
- Detection and mapping of permeable or impermeable subsurface formations (aquifers, paleochannels, fracture zones, faults, karst formations)
- Determination of seawater intrusion and zones of salinization
- Detection of leakage zones in dams
4) Geothermal Investigation:
- Delineation and mapping of the crystalline basement
- Stratigraphic imaging of the subsurface and determination of tectonic features
- Identification of geothermal reservoirs
4) Environmental Protection:
- Imaging the location, boundaries, and volume of waste
- Assessing the suitability of disposal sites and landfills. These activities are supported by field measurements, data analysis, and interpretation using the following geophysical methods and associated equipment:
- Gravimetry – Scintrex CG5
- Magnetics – Geometrics G858, G856, POS1 Overhauser
- Electrical sounding methods – GF Instruments GEPS 2000
- 2D and 3D Electrical Resistivity Tomography – Iris Instruments Syscal Pro; multichannel cables with 48 electrodes at 5 m, 10 m, 20 m, 50 m spacing
- Induced Polarization (IP) – Syscal Pro, Scintrex IPR12
- Electromagnetics
- VLF – ABEM WADI
- Soil conductivity profiling – CMD Explorer
- Transient Electromagnetics (TEM) – Monarch Geoscope TERRATEM
- Cross-hole seismic measurements – GEOTOMOGRAPHIE Sparker, 3-component geophone
Other Activities
Penteli Geomagnetic Observatory
Operation and maintenance of the Penteli Geomagnetic Station. It supports the study of variations in the geomagnetic field across Greece by recording them on daily, annual, and multi-year timescales. It has operated continuously since 1958 and, since 2010, has been a member of INTERMAGNET ( www.intermagnet.org), which collects measurements from 120 observatories worldwide. Equipment: Inside a 10 m tunnel, there is a triaxial magnetometer that continuously measures the three components of the geomagnetic field, as well as a magnetometer that continuously measures the total geomagnetic field intensity. Both instruments are connected to a digital control and recording system that ensures full measurement reliability. All data are analyzed and processed on annual or multi-year bases to study field variation in the Greek territory, to detect and characterize rapid phenomena (magnetic storms, solar flares), and to compute indices of daily magnetic activity. The data are transmitted to INTERMAGNET daily and at 1-second intervals.
Learn more about the departments of the Directorate of General and Applied Geology (DIGEG):
Department of General Geology, Geological Mapping and Applications (GE.XA.E.)