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arXiv · 1109.3635

Avanços na caracterização das estruturas geológicas em subsuperfície da provincia uranífera lagoa real (ba) a partir de dados aerogeofísicos

Suze Nei Pereira Guiamarães·Valiya Mannathal Hamza
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Abstract

In this work we present results of a recent re-evaluation of airborne magnetometric and gamma spectrometric data of the uranium province of Lagoa Real (BA), acquired under the project São Timoteo. The main purpose is to provide new insights into the magnetic and radiometric characteristics of the structural units in this region, derived from a careful analysis of the aeromagnetic and radiometric data of the study area. We provide details of the correction and interpretation procedures employed in data processing. A remarkable feature of the present work has been the judicious use of such interpretation techniques as the vertical derivative, analytic signal and Euler de-convolution, which have lead to identification of a large number of lineaments and basement features in the study area, not identified in previous studies. Prominent among these are the NW-SE trending lineaments in the northern parts, arc shaped features in the west-central parts and circular features in the south and south-western parts of the Lagoa Real province. There are indications that changes in direction of the lineaments are associated with fracture zones, associated with Uranium mineralization processes. Most of the bodies with magnetic contrasts are located at depths less than 500 meters, but there also a number of bodies at depths extending up to depths of 1500m. The results have also allowed determination of a number of structural features not identified in geologic studies as well as in previous interpretations of aeromagnetic data. Joint interpretation of magnetic and gamma spectrometric data have allowed identification of uranium mineralization zones, associated with local metasomatic processes. We conclude that the results obtained are in good agreement with the local structural framework inferred from geologic studies, but significantly different from those reported in earlier studies.

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Suze Nei Pereira Guiamarães, Valiya Mannathal Hamza. 2011-09-16. Avanços na caracterização das estruturas geológicas em subsuperfície da provincia uranífera lagoa real (ba) a partir de dados aerogeofísicos. https://arxiv.org/abs/1109.3635

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