Skip to Main Content
Skip Nav Destination


The Bouguer gravity-anomaly and total-intensity magnetic-anomaly maps covering large areas of central and eastern Brazil define many major structures of the Precambrian basement. Archean granite-gneiss terranes with intervening greenstone belts and high-grade metamorphic zones occur in a series of crustal blocks separated by major discontinuities. This structural pattern essentially was not modified by the Pro-terozoic polycyclic thermo-tectonic processes and Upper Jurassic-Tertiary reactivation of the area. Rather, the Archean block structure greatly influenced the deformation involved in these later events. The magnetic-anomaly data are especially useful in mapping regional fault systems with lengths measured in hundreds of kilometers and mapping of mafic-ultramafic and alkaline intrusions. The distribution of many major mineral deposits is closely related to the major regional crustal structure interpreted from the geophysical data, and thus the regional geophysical data can be used to delimit regional mineralized domains.

You do not currently have access to this chapter.

Figures & Tables





Citing Books via

Close Modal

or Create an Account

Close Modal
Close Modal