Banca de DEFESA: DIEGO DAVILA BESERRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : DIEGO DAVILA BESERRA
DATA : 21/12/2018
HORA: 09:00
LOCAL: Auditório do CCET
TÍTULO:

São Francisco River Strandplain: coastal line retreat related to bedforms, discharge and climate changes

PALAVRAS-CHAVES:

Costal Dynamics; Bedforms; Side scan sonar; Delta

PÁGINAS: 66
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Geociências
RESUMO:

The São Francisco River is located in the northwest portion of Brazil and is the biggest river located entirely in Brazilian territory. This river had been affected by coastline retreat with times of a severe coast line erosion. Such changes in coastline had been attributed to anthropic changes such as dam’s constructions. The propose of this study is understand what is controlling the short-term changes that the coast line of this river is facing. For that, it was used three satellite images, the coast line was drawn for the periods of each cruise, 2009 and 2012 and for 2017. The drawn lines were made through Landsat 7 ETM+ scenes, for 2009 and 2012, and through Landsat 8 OLI scenes for 2017. It was calculated accretion and erosion as well as the accretion/erosion ratio for the areas of northeast and southwest from the São Francisco River Mouth. It was acquired sonographic and seismic data from 2009 and 2012 in order to identify bedforms changes during that period. The sonographic data was acquired through a Side Scan Sonar model 272-TD from Edgetech, and seismic were acquired from a parametric sub-bottom profiler model SES 2000 from Innomar Technologie. It was acquired hydrodynamic data from 2009 to understand the river behavior in its mouth, the equipament used was an Acoustic doppler current profiler (ADCP). Sediment sample from 2009 was collected with a Van Veen Grab in order to understand the sediment distribution along the area. Additionally, it was acquired historical data of rainfall, river runoff, ONI events and SACZ events to find correlations with coastal changes. The data analyze and process showed that the bed forms had not surfed significantly changes, indicating that the river are still transporting enough sediments to the coast. The SACZ events have more influence in rainfall regime than ONI events. The anthropic interference through rivers dams have more influence in coastline changes than rainfall regimes. We concluded that the São Francisco River is the main sediment provider to the coast, in this way, it will always find a new equilibrium when its discharge is controlled.

MEMBROS DA BANCA:
Presidente - 2218779 - HELENICE VITAL
Externo à Instituição - JOSÉ MARIA LANDIM DOMINGUEZ - UFBA
Interno - 2042405 - MOAB PRAXEDES GOMES
Externo à Instituição - WERNER FARKATT TABOSA - UNI-RN