Electronic Material Properties - und Geowissenschaften ...

Investigation of a Doline in NE-Hesse with GPR (Cooperation with HLUG).
The HLUG investigated a depression area in Bad Soden Allendorf. The geophysical
investigation concentrated on the expansion of a depression caused by carstification
of Permian (Zechstein) evaporite formation. The area is overbuilt with roads and
single housings. The depression is situated right beneath a street. Different
measures for stabilization and rehabilitation were under discussion. The investigation
with GPR helped to determine the expansion of the endangered area. With this
information, the covering was realized by a reinforced concrete plate.
Determination of the Thermal Properties of Soils using Geophysical Methods
especially Ground Penetrating Radar and Geoelectrical Methods
(RELGeotherm)
As the spatial distribution of thermal properties is important for the designing and
monitoring of geothermal installations, a non-invasive, high-resolution geophysical
investigation of the thermal properties is eligible.
The basis for a development of a geophysical investigation of geothermal properties
is the knowledge of the interrelation between geothermal and geophysical properties.
Preliminary investigation started to determine quantitatively the dependence of
geothermal properties on relative dielectric permittivity and electrical conductivity.
Improvement of Infiltration Potential Maps using Ground Penetrating Radar
(GPR)
To generate infiltration potential maps, infiltration tests are performed punctually.
Additionally, the geology and the land use are used to interpolate between these
tests. This information can be extracted from maps and other available geotechnical,
geological and other data and reports. The results of the infiltration tests are often
varying even though the geology and the land use are looking similar. These
variations are generated by small scaled discontinuities of the soils structure and the
composition in the shallow subsurface. To achieve a high resolution spatial
extrapolation of the results from infiltration tests, the structure and composition of the
shallow subsurface must be investigated with a high resolution. Especially the
hydrological properties are important. Therefore, the Infiltration process was
monitored in a natural soil on two test sites, in Darmstadt, TU-Lichtwiese and
Dieburg. The infiltration test was accomplished with a double ring Infiltrometer made
of plastic to minimize the influence on the measurements with GPR.
Determination of Hydraulic Properties of sintered HD-PE well Screens
Sintered High Density Polyethylene well screens are hydrophobic. The sintering
process allows control the pore sizes and tortuosity of pores. Additionally HD-PE
filters offer a large open entrance area for the filtrandum (groundwater). Preliminary
investigations have been accomplished to start an industry financed project in 2007.
In this project the hydraulic properties will be investigated in laboratory scale and in
the field.
Determination of Geothermal Properties of Soils and Rocks
For the dimensioning of Borehole Heat exchangers knowledge of thermal properties
of soil is needed. Presently only few data about these properties are existing.
Therefore, laboratory determination for the soils in the area of Calw (Germany) is
performed and a potential map will be developed.
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