Revista Brasileira de Geofísica
Print version ISSN 0102-261X
DIAS, Marcelo S. and BRAGA, Luiz F. S.. Gravity and magnetics in marine mineral exploration. Rev. Bras. Geof. [online]. 2000, vol.18, n.3, pp. 257-268. ISSN 0102-261X. http://dx.doi.org/10.1590/S0102-261X2000000300005.
The potential field methods have been widely used for exploration geophysics since the beginning of the last century. In general, their applications were for preliminary regional mapping of large geological structures related to mineral resources such as: basin boundary faults, grabens and horsts, salt diapirs, basement geometry and heat flow estimates. However, during the last decade, a new branch of equipment (satellite altimeter, gravity and magnetic gradiometers, cesium magnetometers, DGPS and powerful computers) made available an enormous volume of high-resolution data for marine mineral resources exploration. Nowadays, these data are being used for calibrating small density and magnetic susceptibility contrasts that are fundamental for investigating a number of exploration issues: i) velocity correction for 3D and 4D seismic reflection; ii) micro-gravity and micro-magnetic for core geophysics, iii) high resolution density and porosity for pore fluids; iv) potential hazards structures and v) sulfides and polimetallic nodules in oceanic crust. A new vision of these applications is already in use by the mineral exploration industry. The main goal of this paper is to make a brief review and also give some background on those applications.
Keywords : Potential methods; Gravity; Magnetics; Marine mineral resources.