1. PRINCIPLES OF GEOPHYSICS

2. Introduction • Geophysics is an interdisciplinary physical science concerned with the nature of the earth and its environment • Knowledge and techniques of physics, mathematics and chemistry are applied to understand the structure and dynamic behavior of the earth and its environment

3. Introduction • Geophysics is the science which deals with investigating the Earth, using the methods and techniques of Physics • The physical properties of earth materials (rocks, air, and water masses) such as density, elasticity, magnetization, and electrical conductivity can be retrieve from observational measurements of the corresponding physical fields such as gravity, seismic waves, magnetic fields, and various kinds of electrical fields. • Geophysics is a multidisciplinary physical science; it is an incorporation of Physics, Mathematics, and Geology.

4. Geophysical Exploration Techniques • Geophysical methods are divided into two types : Active and Passive • Passive methods (Natural Sources): Incorporate measurements of natural occurring fields or properties of the earth. Ex. SP, Magnetotelluric (MT), Telluric, Gravity, Magnetic. • Active Methods (Induced Sources) : A signal is injected into the earth and then measure how the earth respond to the signal. Ex. DC. Resistivity, Seismic Refraction, IP, EM, Mise-A-LA-Masse, GPR.

5. Common Applications • Geophysical Exploration Techniques can be used in • oil and gas exploration • mineral exploration • diamond exploration (kimberlites) • Hydrogeology • geotechnical and engineering studies • tectonic studies • earthquake hazard assessment • archaeology

6. Geophysical methods and their applications