CHAPTER 2: ADVANCES IN APPLICATIONS
H.O. Seigel, A. W. Howland-Rose, Ian M. Johnson, William Frangos, R. Ehrat, I. Brcic, W.H. Meyer, J.E. Hanneson, Gerald W. Hohmann*, A.C. Tripp, J.D. Klein, M.O. Halverson, J. Kingman, T.W. Grant, 1990. "ADVANCES IN APPLICATIONS", Induced Polarization: Applications and Case Histories, James B. Fink, Ben K. Sternberg, Edgar O. McAlister, W. Gordon Wieduwilt, Stanley H. Ward
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The magnetic induced polarization (MIP) method determines the variation of the induced polarization and resistivity of the earth through measurements of the magnetic field associated with galvanic current flow in the earth, rather than the electric field, as in the traditional induced polarization (IP) or electrical induced polarization (EIP) method. Important differences between the MIP and EIP methods are evident in field practice, mathematical theory, and field results. For example, the MIP method is insensitive to horizontal layering in the earth and reflects only lateral variations in its electrical properties. MIP also provides an enhanced ability to detect the presence of bodies of anomalous electrical properties even through a highly conducting surface layer. For this reason the MIP methods primary application is in regions of highly conducting (e.g., saline) overburden or weathered rock, such as in Australia. MIP responses tend to be more complex and varied in pattern than responses normally encountered in EIP measurements. For example, polarity reversals are the rule in MIP but are rarely encountered in EIP. MIP employs high-sensitivity component magnetometers as basic sensors. These are small relative to the length of the electric dipole sensors normally employed in EIP, and, therefore, provide relatively higher geometric resolving power.
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A monograph describing the state-of-the-art of the induced polarization (IP) method appropriately records the evolution of its development and mention of those who were involved. Electrical polarization effects in soils and rocks were first recognized by Dr. Conrad Schlumberger about 1911 in France at a time when geophysics was first being considered as an aid to mineral prospecting. World War I intervened and Schlumberger's work in IP investigations was sidetracked. During the 1920s Schlumberger began to work on borehole logging methods for petroleum exploration. After 1929, the U.S.S.R. embarked upon an extensive geophysical program for exploring for petroleum in the Grozny region north of the Caucasus. Experimentation with IP logging for formation evaluation was investigated but failed due to poor instrumentation. During the 1930s, there were a number of attempts to use the polarization technique for the detection of oil and ore bodies.
During World War II, the U.S. Naval Ordnance Laboratory worked on an electrical polarization technique for detecting explosive mines in water. After the war Dr. D.F. Bleil, with assistance of the U.S. Geological Survey, field tested the technique in two mineralized areas. The idea was brought to the attention of Newmont Mining Corporation by Radio Frequency Laboratories located in Boonton, New Jersey, and Dr. Arthur Brant, University of Toronto, was brought in as a consultant. In the fall of 1948, Dr. H.O. Seigel demonstrated that the IP method was reliable. In 1949 Newmont Exploration Ltd. Was quickly established in Jerome, Arizona under the leadership of Dr. Brant to investigate and exploit the IP method. In the fall of 1952, a group at Massachusetts Institute of Technology headed by Dr. Ted Madden began to investigate the IP phenomenon and work was carried out in association with several mining companies. At the New Mexico Institute of Mining and Technology, Dr. V. Vacquier and his group attempted in 1953 to apply IP techniques to groundwater exploration. Between 1955 and 1960, several universities in the United States began to investigate the IP phenomenon and a few mining companies started their own research groups.