Magnetic survey

Keywords plate tectonics, sedimentary basins, source rocks, maturation, migration, reservoir rocks, traps, seismic, gravity survey, magnetic survey, geochemistry, mudlogs, field studies. 

Magnetic survey A directional survey in which the direction is determined by a magnetic compass deflecting the earth s magnetic field. 

Monel (K monel) A permanently nonmagnetic alloy used in making portions of downhole tools in the bottomhole assembly (BHA) where the magnetic survey tools are placed for obtaining magnetic direction information. Monel refers to a family of nickel-copper alloys. 

In Stoddart zone, 2 holes have been drilled to test the historical Au, Mo, Cu soil anomaly, coincident with airborne magnetic survey anomaly. The drill holes revealed for the first time the occurrence of porphyry-style Cu-Mo mineralization in the Freegold Mountain area. Mineralization occurs as either quartz-chalcopyrite-molybdenite veins and microstockworks, or chalcopyrite molybdenite disseminations. 

Numerous volcanic centres occur on the seafloor of the Sicily Channel (Fig. 8.1). Calanchi et al. (1989) recognised at least ten recent submarine volcanoes of various dimensions, mostly located along NW-SE regional faults. Some of these volcanoes have erupted during historical times others are covered by undisturbed Pliocene-Quaternary sediments and have been detected by seismic profiles and magnetic survey (Allan and Morelli 1971). 

Measurements in airborne magnetic surveys are usually taken along the total magnetic field, and can be computed approximately as... 

The results of Dr. Weymouth s magnetic survey are in accordance with the soil chemical analyses (J5). The palisade lines, suspected interior structural features, and parade ground are clearly depicted on the line contour magnetic maps. Furthermore, the 1-m internal grid unit employed in that survey allowed for more accurate definition of the fort boundaries, and the 48-m inside dimension indicated by the magnetic results compares quite favorably with that suggested for the fort by documentary sources. 

Magnetic surveys were tried out after the Askania... 

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