Question

method that injects very high current into 75, Induond polaniation is an the ground and imcanures A. Acquisition Decay Tie R. Acive Decay Time C Active, Delay Time D. Alhernative, Diurnal Time 76. You have been requested to conduct a geophysical survey over a target area that is suspected to contain disseminated sulphide mineralization in a gabbroic host rock. What would be the best electromagnetic geophysical method to use given the target is disseminated metallie A. Resistivity B. Self-Potential. C. Induced Polarization 77. What is the mechanism of rock polarization which depends on the presence of metallie minerals and is important for mineral exploration? A. Electron Polarization. B. Membrane Polarization. C. Electrolyte Polarization D. Memory Polarization. 78. What are the three main systems used for the Induced A. Frequency Domain, Spectre IP, Decay IP B. Spectral IP, Phase Domain, Amplitude Domain. C. Time Domain, Frequency Domain, Spectral IP. D. None of the above. Geology 2112: Final Exam Page 20 of 30

Answer 1

75. Induced polarization injects direct current into soil, which is result of electrochemical process, it's an active geophysical method. After switching off the current it takes time to induced voltage to decay which is called as decay time.

Hence, the correct option is B.

76. The correct option is C, induced polarisation ,IP.

It's used for sulfur mineralization, gold mineralization undifferentiated with meta sedimentary rocks. It measures PFE and phase angle of signal receiving and transmitted.

77. A. Electric polarization. It is carried out through electric phenomenon under current stimulation of induced polarization and voltage decay processing.

78. C. Time domain, Frequency domain, Spectral IP.

It works on the principle of resistivity measurements. It also uses electromagnetic method to create geophysical images and see overvoltage effect.

The time domain IP is used to measure the potential difference and voltage decay or overvoltage as a function of time.