Banca de QUALIFICAÇÃO: LUANNY BÁRBARA DE MEDEIROS FERNANDES

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : LUANNY BÁRBARA DE MEDEIROS FERNANDES
DATA : 02/07/2018
HORA: 14:30
LOCAL: Auditório do LGGP I
TÍTULO:

STRUCTURAL CONTROLS OF BASIC DIKE SWARMS IN THE CENTRAL-EASTERN PORTION OF THE PARNAIBA BASIN

PALAVRAS-CHAVES:

Parnaiba Basin; Structural analysis;Dike swarms

PÁGINAS: 30
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Geociências
RESUMO:

The Parnaiba Basin contains basic magmatic suites of different ages, whose origins are related to the Pangea breakup events and the formation of the Atlantic Ocean. In this tectonic context, intrusive (mainly dikes and sills) and extrusive rocks were emplaced along two activity peaks, recognized from a chronostratigraphic point of view as Mosquito (Early Jurassic) and Sardinha (Early Cretaceous) suites. In the southeastern and central-eastern portions of the basin, we highlight the occurrence of basic dike swarms with different orientations, whose ages are still little known. To contribute to the knowledge of these bodies, remote sensing and field data were analysed to define the geometry and structural controls of these intrusions, their thermal effects on their sedimentary country rocks and their correlation with regional tectonic events. The analysis of remote sensing images allowed to characterize a family of NE-SW-trending dominant lineaments, in the southeast border of the basin, and two others, ENE-WSW and NWSW-trending sets, in the central-east region. Field data show that mapped photolineaments generally correspond to basalt and/or diabase dikes associated with fractures systems and normal faults affecting the basin rock units. Considering the dispersion in the orientation of the dike systems, two hypotheses are considered to structural controls and age of these swarms. In the first, the different dike systems are ascribed to the Sardinha Suite, formed during the South Atlantic rift event; the different orientations of the sets are explained by the reactivation of preexisting structures in the basin, plus new fractures formed in this event. In a second hypothesis, to be tested by geochronological data, the dike swarms are formed in different tectonic phases, such as the Early Cretaceous event, older reactivations of the Transbrasilian Lineament or younger events, such as the opening of the Brazilian Equatorial Margin.

MEMBROS DA BANCA:
Presidente - 346469 - EMANUEL FERRAZ JARDIM DE SA
Interno - 1217847 - FERNANDO CESAR ALVES DA SILVA
Interno - 350630 - ZORANO SERGIO DE SOUZA