References and examples for projects


References

National and international references

Selected clients
National

  • GVV - Gesellschaft zur Verwahrung und Verwertung von stillgelegten Bergwerksbetrieben mbH
  • LMBV - Lausitzer und Mitteldeutsche Bergbauverwaltungsgesellschaft mbH
  • NDH-E - NDH Entsorgungsbetreibergesellschaft mbH
  • Forschungszentrum Karlsruhe in der Helmholzgemeinschaft
  • Rheinkalk GmbH - Lhoist Group
  • BfS - Bundesamt für Strahlenschutz
  • DBE - Deutsche Gesellschaft zum Bau und Betrieb von Endlagern für Abfallstoffe mbH
  • GSES - Glückauf Sondershausen Entwicklungs- und Sicherungsgesellschaft mbH
  • K+S AG
  • esco - european salt company GmbH & Co. KG

International

  • ICL Fertilizers Europe, United Kingdom - Great Britain and Northern Ireland
  • Cementos Pacasmayo S.A.A, Republic of Peru
  • SALSUD - Salmueras Sudamericanas, Republic of Peru
  • North American Salt Company, United States of America
  • Kopalnia Soli Klodawa S.A., Republic of Poland

Selected clients of K-UTEC in the field of geophysical exploration

  • Bundesamt für Strahlenschutz (BfS), Salzgitter
  • Bundesanstalt für Geowissenschaften und Rohstoffe (BGR), Hannover
  • C & E Consulting und Engineering GmbH, Chemnitz
  • Cleveland Potash Limited, Boulby, Great Britain
  • Cementos Pacasmayo, Peru
  • Dr. H. Marx GmbH, Spiesen-Elversberg
  • Fraunhofer Institut: Einrichtung für akustische Diagnose und Qualitätssicherung EADQ, Dresden
  • Gesellschaft zur Verwahrung und Verwertung von stillgelegten Bergwerksbetrieben mbH (GVV), Sondershausen
  • Leibnitz Institute, Hannover
  • Glückauf Sondershausen Entwicklungs- und Sicherungsgesellschaft mbH (GSES), Sondershausen
  • Grube Teutschenthal Sicherungsgesellschaft mbH & Co. KG (GTS), Teutschenthal
  • Grundwasser- und Geoforschung, Neunkirchen
  • Ingenieurbüro Dipl.-Ing. Herold, Weimar 
  • Ingenieurbüro Dr. Rey & Spillmann GmbH, Sangerhausen
  • Ingenieurbüro Peter, Quedlinburg
  • K + S Kali GmbH, Kassel
  • LAGB Landesamt für Geologie und Bergwesen Sachsen-Anhalt, Halle
  • LMBV
  • Menteroda Recycling GmbH, Menteroda 
  • Mitteldeutsches Zentrum für geomechanische Dienste und Forschung GmbH (MZGF), Espenhain
  • Nordhäuser Entsorgungsbetreibergesellschaft (NDH-E), Bleicherode
  • Premogovnik Velenje, Slovenia
  • Rheinkalk GmbH, Wülfrath
  • Salt Union Limited, Winsford, Great Britain
  • Solvay Salz GmbH, Borth
  • Stadtverwaltung Bad Frankenhausen
  • Stadtverwaltung Sondershausen
  • Südwestdeutsche Salzwerke AG, Heilbronn
  • Terra Data GmbH, Sangerhausen
  • Universität Leipzig, Institut für Geophysik und Geologie, Leipzig
  • VNG Verbundnetz Gas AG, Kirchheiligen
  • Wacker-Chemie GmbH, Salzbergwerk Stetten, Stetten

Examples for projects

VELGASPREVENT

Development of a geophysical borehole measurement technology for the preventive exploration of the blowout hazard in the mining forefront of lignite mine "Premogovnik Velenje" (Slovenia)

The aim of this international R&D project is the creation of a measurement and interpretation technology for prospection of rock mechanical hazard areas in the form of unpredicted coal blowouts. The prospection is supposed to be carried out by surveying with the help of long horizontal exploration boreholes that go into the undeveloped forefront of the mine. The research project is supported by the Federal Ministry of Economy and Labour in the framework of a program called "Promotion for the increase of the INNOvation competence of midsize companies" (PRO INNO II).

Cooperation Partners

  • Bo-Ra-tec GmbH, Weimar, Germany
  • Brunnen- und Bohrlochinspektion GmbH, Gommern, Germany
  • Kali-Umwelttechnik GmbH, Sondershausen, Germany
  • Premogovnik Velenje, Velenje, Slowenia
  • Technische Universität Clausthal, Department of Geophysics, Clausthal-Zellerfeld, Germany
  • Geophysik Support Klaus Lorenz, Steinbach, Germany
  • Fraunhofer Institut Zerstörungsfreie Prüfverfahren, Dresden, Germany

Background
The Slovenian lignite mine "Premogovnik Velenje" excavates hard brown coal from seams 20 to 160 m high by longwall mining. The lens-shaped coal seam is 8.3 km long, 1.5 to 2.5 km wide and lies in a depth of 200 to 500 m. The mine provides the nearby caloric power plant Šoštanj with an annual amount of about 4 million tons of raw brown coal. Having a 30 % portion of the electric energy supply for Slovenia this power plant is of strategic importance for the economic stability of Slovenia as an EU accession country.
Because of various tectonic faults that cross the deposit the mining situation is complex. Especially in tectonically modified areas a hazard of sudden and not predictable gas and coal dust blowouts exists. Since the start of excavation in the mine more than 100 years ago many serious accidents have occured. These accidents resulted in deaths and considerable and irreversible damages to the mine and the equipment in the mine.

 

Detailed investigation of the Sondershausen Castle foundations

Is the ground capable of bearing loads?

The historically significant Sondershausen Castle is structurally unsound. The present condition of the building requires urgent safety and renovation measures to ensure its stability. However, a successful safety and renovation programme requires clarification of the causes for the damage to be able to perform a progress with prospect. The present damage shows itself in the form of cracks, settlements and tilting indicate that the damage is mainly caused by unstable foundations and underground phenomena. In the framework of a complex foundation investigation, Kali-Umwelttechnik was entrusted to determine the causes for the foundation damage through inter-disciplinary work involving geology, geophysics, geomechanics, ground mechanics, statics and architecture and to suggest renovation measures based on the findings.
For the entire investigation project the following geophysical procedures were applied:

  • Seismics: refraction seismics, reflection seismics , ultrasonic seismics (sonar)
  • Seismic tomography
  • Geoelectric tomography: so called pseudo sections
  • Radiometric surveys / surface radar and bore hole radar
  • Radar tomography

Beside surface and bore hole techniques, investigations of the masonry by radar were carried out as well as a geophysical-geotechnical assessment of the exploration drillings. With the help of a versatile measurement program it was possible to make detailed conclusions regarding the state and depth of the loose overburden and the nature of the building grounds (multi-coloured sandstone).

It is possible, for example, to obtain a distribution of the multi-coloured sandstone's velocities in the zone of the castle complex from seismic measurements. The results allow us to make conclusions about the strength of the multi-coloured sandstone and consequently about the strength of the building grounds. Areas with low velocity are interpreted as badly weathered or unstable, while high velocity indicates compact rock.

From the results of the seismic survey of the surface of the sandstone bedrock along with the known topography, one can calculate the thickness of the loose overburden covering the multi-coloured sandstone.

Another example for measurement results origins from electeomagnetic-tomographic survey. With the help of borehole radar the velocity and absorption rates of electromagnetic waves were measured between two boreholes. In this example the boreholes did not run parallel but lied at an angle to each other.

The measurement result produces the shown tomograms of velocity and specific electrical resistance. The zone in the middle of the two boreholes represents an area with increased occurence of crevasses. The results however show that cavities of significant size can be excluded. 

With geophysical investigations at Sondershausen Castle the structure and quality of the building grounds and its foundations could be illustrated plausibly. Along with the proof of crevasses and fractured zones of various dimensions areas could be depicted that show high thicknesses of loose overburden, also in the form of embankments, as well as highly weathered sandstone. These areas have an inadequate building ground. 


Geophysical exploration of a hardrock deposit

Is the excavation of the deposit profitable?

Within the framework of planning of the mining concept of the Rheinischen Kalksteinwerke Wülfrath (limestone works), Kali-Umwelttechnik (K-UTEC) was entrusted with the geophysical prospection to assess the mining profitability of a limestone deposit. The exploration program involved the following tasks: 

  • Proof of the limestone complexes and their differentiation from adjoining rock. Adjoining rocks are mainly silt stone and clay shale.
  • Determination of the depth and the extent of the limestone deposit.
  • Identification of anomalies in the deposit's structure, e.g. tectonically caused dislocations (faults, foldings), phenomena caused by subrosion, discordances, etc.
  • Determination of the inclination of the limestone body.
  • Determination of the overburden's thickness covering the exploitable limestone deposit.
  • Recommendations for borehole sites for the subsequent drilling programme.-

To be able to solve these questions, K-UTEC applied various geophysical exploration methods that complement each other perfectly in this project:

  • Seismics: Refraction seismics (Ra-S) and reflexion seismics (Rx-S)
  • Geoelectrics: Direct current geo electrics (2D with multi electrode arrangement)
  • Borehole radar: Dipole directional and non-directional measurements

The results of seismic surveys make substancial conclusions about the course, the fluctuation and the variation of dip in the limestone body's upper limit possible. At the same time the height of the loose overburden is determined. Additionally the existence of intrusions (in this case clayey inclusions, Iberg lime, sandstone) can easily be recognised in seismograms.

The direct current geoelectricity survey records an underground resistance distribution of the explored bedrock. Various types of rock exhibit characteristic resistance behaviour, which makes it possible to assign measured values to certain rock layers. The geoelectric results support the conclusions attained from a seismic survey.

Using borehole radar the position and extent of karst formation zones can be detected as well as the dip of strata. With the help of the penetration depth of the radar waves a rough estimate of the limestone's quality can be carried out. 

By the combination of all geophysical measurement results as a complex interpretation, reliable statements about the investigated rock body can be obtained:

  • Bedding condition of the limestone deposit
  • Dip of strata depending on their depths
  • Dip direction
  • Degree of weathering
  • Existence, position and extent of fissure systems
  • Boundaries of the limestone deposit