Banca de DEFESA: MARISTELA ALMADA GOMES DE OLIVEIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : MARISTELA ALMADA GOMES DE OLIVEIRA
DATE: 14/09/2021
TIME: 09:00
LOCAL: Plataforma RNP
TITLE:

Delimitation of potencial zones and hydrochemical analysis of the underground water in the hydrographic region IV-PIABANHA (RJ)

KEY WORDS:

Fractured aquifer. GIS. Hierarchic Process Analysis. Hydrogeochemistry.

PAGES: 94
BIG AREA: Ciências Exatas e da Terra
AREA: Geociências
SUBÁREA: Geologia
SPECIALTY: Hidrogeologia
SUMMARY:

The complexity of the water behavior in fractured environments, very frequent in Rio de Janeiro, represents a challenge for the management of these resources. The Piabanha Hydrographic Region (RH-IV) is the fourth hydrographic region in the state of Rio de Janeiro that most explores underground water, with constant problems of water rationing and little knowledge of the hydrochemical and hydrodynamic conditions of its aquifers, which are predominantly fractured. The objectives of this work were to delimit the potential zones for the exploration of groundwater and to discuss the hydrochemical behavior in RH-IV, as a model for studies for other regions. The delimitation of potential zones, using remote sensing, Geographic Information System (GIS) and Analytical Hierarchy Process (AHP), constituted an effective and inexpensive tool, if compared to other surveys (geophysical, geological and hydrogeological). The hydrochemical analysis was performed from secondary data evaluated by diagrams, hydrochemical ratios and salinization analysis (RAS - Sodium Adsorption Risk), considering not only the natural but also anthropogenic influence on the groundwater of RH-IV . The groundwater potential map was prepared considering five classes: very high (17.61%), high (35.56%), moderate (28.16%), low (11.05%) and very low (7.61%). The most relevant criteria for groundwater potential in RH-IV were soils, lineament density, geology and precipitation. To provide subsidies for the analysis of hydrochemical data, a preliminary flow model was generated, which pointed the groundwater flow from SE to NW, towards the Paraíba do Sul River. The main recharge of the underground system occurs in the Serra dos Órgãos region , in the municipalities of Petrópolis and Teresópolis, while the discharge in the Três Rios and Carmo region. Six hydrochemical types of groundwater were classified, predominantly calcium bicarbonate water (48%), followed by sodium bicarbonate (29%). Magnesian bicarbonate (10%), sodium chlorinated (10%), mixed bicarbonate (2%) and magnesium sulfate (2%) waters were also identified. Anomalous values of NO3-, Fe, Cd, U and Mn were identified in RH-IV aquifers. As for the risk of salinization, 94% of the samples had zero or low risk. Wells that presented medium or high risk of salinization are under anthropogenic influence from urbanization and/or irrigation. Evidence of salinization of the RH-IV aquifers should be considered in the water resources management model, in view of the uses of groundwater, the remediation difficulties for aquifer systems and the possible evolution of this situation in RH-IV throughout the time.

BANKING MEMBERS:
Externa à Instituição - CARLA SEMIRAMIS SILVEIRA
Interno - 1560386 - ALAN WANDERLEY ALBUQUERQUE MIRANDA
Externa ao Programa - 1767097 - ERIKA CORTINES
Presidente - 1767261 - OLGA VENIMAR DE OLIVEIRA GOMES