Which geophysical methods are utilized to investigate groundwater pollution?

Which geophysical methods are utilized to investigate groundwater pollution?

• A. Seismic waves and sonar
• B. Geomagnetics and electrical resistivity
• C. Ground-penetrating radar and thermal imaging
• D. Magnetic resonance and ultrasonic sensors

Answer: (B)

The selection of geomagnetics and electrical resistivity as the appropriate geophysical methods for investigating groundwater pollution is based on their effectiveness in detecting subtle changes in subsurface materials that may indicate contamination. Geomagnetics measures variations in the Earth's magnetic field which can be influenced by the presence of different minerals or pollutants within the groundwater. This method is beneficial in identifying areas where contaminants may have altered the natural magnetic properties of the soil or underlying materials. Electrical resistivity is particularly useful because different substances, including pollutants, have distinct resistivity values. By applying a current through the ground and measuring the resulting voltage, one can map out resistive and conductive zones. Polluted areas often exhibit different resistivity characteristics compared to clean groundwater due to the presence of dissolved contaminants that change the electrical behavior of the groundwater. These two methods provide vital information about subsurface conditions and are commonly employed in environmental assessments and remediation planning for groundwater protection. This makes them well-suited for investigating groundwater pollution, focusing on the identification and characterization of contaminated zones.

The selection of geomagnetics and electrical resistivity as the appropriate geophysical methods for investigating groundwater pollution is based on their effectiveness in detecting subtle changes in subsurface materials that may indicate contamination.

Geomagnetics measures variations in the Earth's magnetic field which can be influenced by the presence of different minerals or pollutants within the groundwater. This method is beneficial in identifying areas where contaminants may have altered the natural magnetic properties of the soil or underlying materials.

Electrical resistivity is particularly useful because different substances, including pollutants, have distinct resistivity values. By applying a current through the ground and measuring the resulting voltage, one can map out resistive and conductive zones. Polluted areas often exhibit different resistivity characteristics compared to clean groundwater due to the presence of dissolved contaminants that change the electrical behavior of the groundwater.

These two methods provide vital information about subsurface conditions and are commonly employed in environmental assessments and remediation planning for groundwater protection. This makes them well-suited for investigating groundwater pollution, focusing on the identification and characterization of contaminated zones.