Geophysical characterization of soil contamination - field and laboratory studies for an investigation program in Nepal.
Research output: Thesis › Doctoral Thesis
Widespread pollution of vadose and saturated zones worldwide raised a concern to find an efficient and sustainable noninvasive methodology for pollution characterization. Geophysical field and laboratory methods including available well logging techniques have been tested in order to develop a methodology for noninvasive characterization; tests are combined with laboratory measurements and model calculations in order to demonstrate the sensitivity. Induced polarization (IP), chargeability soundings and 2d resistivity imaging results were indicative, if the contaminated layer introduces a resistivity anomaly. Spectral Induced Polarization (SIP) imaging combined with the laboratory investigations of soil samples can apparently distinguishes a contaminated body. In addition, soil samples were artificially contaminated and their electrical behavior was studied in the low frequency range 10-3 to 103 Hz. Due to the effect of organic contamination, the real part of conductivity increases immediately after the mixing with the contaminants. The imaginary part decreased due to contamination. As a new result it was observed, that the clay organic reaction process is controlled directly by the organic carbon content. Thus, a combination of conventional field investigation and sample analysis with a methodic set of complex resistivity or conductivity measurements gives a more detailed picture of the contamination and the contamination controlling processes.
|Translated title of the contribution||Geophysikalische Charakterisierung von Schadstoffkontaminationen des Untergrundes - Feld- und Laborstudien für ein Untersuchungsprogramm in Nepal|
|Publication status||Published - 2006|