Register now or log in to join your professional community.
Exploration geophysics is an applied branch of geophysics, which uses physical methods (such as seismic, gravitational, magnetic, electrical and electromagnetic) at the surface of the Earth to measure the physical properties of the subsurface, along with the anomalies in those properties.
Groundwater exploration is the investigation of underground formations to understand the hydrologic cycle, know the groundwater quality, and identify the nature, number and type of aquifers. There are different groundwater exploration methods. Surface geophysical method is one of the groundwater investigation methods. One of the surface geophysical methods is therefore the vertical electrical sounding method. Vertical electrical sounding (VES) is one to provide valuable information regarding the vertical successions of subsurface geo-materials in terms of their individual thicknesses and corresponding resistivity values. It is rapid and much effective in estimating aquifer thickness of an area and is cost effective technique for groundwater study.
Exploration geophysics is an applied branch of geophysics, which uses physical methods (such as seismic, gravitational, magnetic, electrical and electromagnetic) at the surface of the Earth to measure the physical properties of the subsurface, along with the anomalies in those properties.
Traditional solution: Drill several boreholes & install wells: Expensive Labor Intensive Time If site is contaminated: Disposal of contaminated core Clean equipment
Geophysical Investigations : Geophysical investigations involve simple methods of study made on the surface with the aim of ascertaining subsurface detail. This is achieved by measuring certain physical properties and interpreting them mainly in terms of subsurface geology. Importance of :
eophysical Investigations : These investigations are carried out quickly.
This means large area can be investigated in a reasonable short period and hence time is saved. The geophysical instruments used in the field are simple, portable and can be operated easily.
Importance of Geophysical Investigations Different inferences to suit different purposes can be drawn from the same field data, for example electric resistivity data can be interpreted for knowing subsurface of rock types, geological structures, groundwater conditions, ore deposits depth to the bed rock, etc. Hence the investigations are multipurpose
ELECTRICAL RESISTIVITY METHOD : The electrical resistivity method involves the measurement of the apparent resistivity of soils and rock as a function of depth or position.
It is calculated by dividing the measured potential difference by the input current and multiplying by a geometric factor specific to the array being used and electrode spacing
Electrical Resistivity Method : All geological formations have a property called electrical resistivity which determines the ease with which electric current flows through them. This resistivity is expressed in the units of Ώm ohms meter and is indicated by the symbol ᵖ
Electrical Methods ELECTRICAL RESISTIVITY METHOD :The electrical resistivity of a rock formation limits the amount of current passing through the formation when an electrical potential is applied
