Banca de QUALIFICAÇÃO: BRENNDA ANDREZZA VIANA DE MENDONÇA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : BRENNDA ANDREZZA VIANA DE MENDONÇA
DATE: 14/09/2021
TIME: 09:30
LOCAL: videoconferência
TITLE:

Tectonic-sedimentary features of siliciclastic sequences in flexural and faulted margins: Examples in the Rio do Peixe basin, NE Brazil.

KEY WORDS:

Interior Basins of Northeast Brazil; Rio do Peixe Basin; Santa Helena Step; arenoconglomeratic units, sinsedimentary deformation.

PAGES: 21
BIG AREA: Ciências Exatas e da Terra
AREA: Geociências
SUMMARY:

The Rio do Peixe Basin is located almost entirely in the state of Paraíba (Brazil) and is part of a set called “Interior Basins of the Brazilian Northeast”. The basin compartment consists of four half-grabens (or sub-basins) – from west to east: Icozinho, Brejo das Freiras, Sousa and Pombal, with larger axes following the trends of the shear zones that cut the Precambrian crystalline basement (Borborema province). The Santa Helena Step includes the connection region of the Brejo das Freiras and Sousa half-grabens, comprising structural trends from different directions (NE-SW and E-W), which gives particular characteristics to the area. Previous maps of the Rio do Peixe Basin indicate that the relay ramp corresponding to the Santa Helena Step is completely or almost completely filled by the Antenor Navarro Formation. In the present proposal, the region occupied by the Rio Piranhas Formation was significantly expanded, with the Antenor Navarro Formation being restricted to the vicinity of the non-conformity with the crystalline basement. Since both units are arenoconglomeratic, some characteristics, if analyzed together, became decisive in the differentiation between them, such as coloration and selection of lithotypes, selection, direction of paleocurrents and features of syndepositional tectonic deformation to sinlitification, The presence of tectonic structures sin-depositional was shown to be an important criterion in the characterization of the lithotypes of the Rio Piranhas Formation. In general, the most common syntectonic structures in the Rio do Peixe Basin are deformation bands. In the study area, it was possible to identify other deformational structures, such as clastic dykes and what was referred to here as “sandstone injection features”. An important fact is the alignment of the points where these structures were identified with the main faults that delimit the relay ramp. This alignment suggests that the activity of these faults actually acted as a triggering agent for the formation of these structures. The study of these structures, in order to list and classify them with terms already referred to in the literature, in addition to describing the possible deformation mechanisms involved, is one of the objectives of this work, in addition to the description of diagenetic aspects of these sandstones, through the thin sections analysis.

BANKING MEMBERS:
Presidente - 346469 - EMANUEL FERRAZ JARDIM DE SA
Externa ao Programa - 277437 - MARCELA MARQUES VIEIRA
Interna - 1149363 - VALERIA CENTURION CORDOBA