The Lourenço region, located in the north-central portion of the state of
Amapá, is inserted into the geological context of the Guianense Complex border,
where many mineral deposits occur. It is characterized as a gold province, with few
detailed geological studies. The objective of the study is to present the results
relative to geological mapping, with emphasis in the structural data, to increase the
knowledge of the geometry and kinematics in the exposed rocks, as well as correlate
the main tectonic events in the region with the structures found in this work. The area
that was chosen for this work is located on the border of the cities: Oiapoque
(northwest) and Calçoene (southeast), nearby the Lourenço Village, northeast of
Sierra Lombarda. The study used several remote sensing products in this mapping,
including: satellite, radar and aerogeophysical images, allowing through analyzing
visual, interpretations at different scales, which had as main objective the
visualization and the location of the macrostructures (lineations and structural
lineaments), aiming to better characterize the deformation behavior of the area. Were
recognized five main groups of rocks: gneisses, amphibolites, granites (TTG suite),
granitoids and mafic rocks, whose geological context is characteristic of high-grade
terrains, and later the inclusion of Cassiporé Mafic Dikes that originated the mafic
rocks. Structurally, the area is embedded in Shear Belt Tumucumaque, which shows
similar features to Itacaiúnas Belt, with general NW-SE direction, which predominate
transcurrent systems outlined by asymmetric and symmetric duplexes, also showing
deformation with NE-SW direction, attributed to events subsequent to formation of
the general direction.
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