Premium
Gravimetric study of a potential mineral deposit in the Itapororoca region, Brazil
Author(s) -
Mantovani Marta S.M.,
Shukowsky Wladimir,
De Brito Neves B.B.,
Rugenski André
Publication year - 2008
Publication title -
geophysical prospecting
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.735
H-Index - 79
eISSN - 1365-2478
pISSN - 0016-8025
DOI - 10.1111/j.1365-2478.2008.00696.x
Subject(s) - bouguer anomaly , geology , gravity anomaly , outcrop , volcano , levelling , gravimetry , gravimetric analysis , magnetic anomaly , economic geology , hydrothermal circulation , regional geology , gemology , anomaly (physics) , altitude (triangle) , geophysics , geodesy , seismology , geochemistry , engineering geology , volcanism , tectonics , geometry , geotechnical engineering , chemistry , oil field , condensed matter physics , paleontology , reservoir modeling , physics , organic chemistry , mathematics
A semi‐detailed gravity survey was carried out over an area of 650 km 2 localized in the Eo‐Neoproterozoic coastal zone of Paraiba State where 548 new gravity stations were added to the existing database. Gravity measurements were made with a LaCoste and Romberg model G meter with a precision of 0.04 mGal. The altitude was determined by barometric levelling with a fixed base achieving a 1.2 m measure of uncertainty, corresponding to an overall accuracy of 0.24 mGal for the Bouguer anomaly. The residual Bouguer map for a 7th degree regional polynomial showed a circumscribed negative anomaly coincident with a localized aero‐magnetic anomaly and with hydro‐thermally altered outcrops, near the city of Itapororoca. The 3D gravity modelling, constrained by geologic mapping was interpreted as a low density, fractured and/or altered material with a most probable volume of approximately 23 km 3 , extending to about 8,500 m depth. This result is in accordance with a volcanic body associated with hydrothermal processes accompanied by surface mineralization evidence, which may be of interest to the mining industry.