@PhDThesis{AlmeidaFo:1983:CoMe,
author = "Almeida Filho, Raimundo",
title = "Sensoriamento remoto orbital aplicado {\`a}
prospec{\c{c}}{\~a}o mineral nas prov{\'{\i}}ncias
estan{\'{\i}}feras de Goi{\'a}s e Rond{\^o}nia: uma
contribui{\c{c}}{\~a}o metodol{\'o}gica",
school = "Universidade de S{\~a}o Paulo",
year = "1983",
address = "S{\~a}o Paulo",
month = "1983",
keywords = "geologia, Goi{\'a}s (estado), Rond{\^o}nia (estado),
prospec{\c{c}}{\~a}o mineral, geology, estanho, mineral
prospection, tin.",
abstract = "Discute-se neste trabalho uma linha metodol{\'o}gica de
utiliza{\c{c}}{\~a}o de dados de sensoriamento remoto orbital,
como ferramenta de auxilio a campanhas de prospec{\c{c}}{\~a}o
mineral, exemplificada no estudo de corpos gran{\'{\i}}ticos das
Prov{\'{\i}}ncias Estan{\'{\i}}feras de Goi{\'a}s e de
Rond{\^o}nia. Inicialmente faz-se uma discuss{\~a}o do papel de
diversos par{\^a}metros que interagem para compor o sinal gravado
pelos sistemas sensores. S{\~a}o par{\^a}metros fundamentais no
processo de an{\'a}lise e interpreta{\c{c}}{\~a}o de dados
multispectrais em geologia: as caracter{\'{\i}}sticas
fisiogr{\'a}ficas da regi{\~a}o; as caracter{\'{\i}}sticas
geol{\'o}gicas do {"}alvo{"} pesquisado; o papel das
vari{\'a}veis sazonais (cobertura vegetal e condi{\c{c}}{\~o}es
de ilumina{\c{c}}{\~a}o); as caracter{\'{\i}}sticas do sistema
sensor (resolu{\c{c}}{\~o}es); e as t{\'e}cnicas de realce de
imagens digitais atrav{\'e}s do emprego de computadores. A
utiliza{\c{c}}{\~a}o de imagens digitais/multispectrais do
sensor MSS-LANDSAT, levando em considera{\c{c}}{\~a}o todos os
aspectos acima, permitiu a discrimina{\c{c}}{\~a}o de {\'a}reas
de ocorr{\^e}ncias de f{\'a}ceis greisenizadas ({"}lato
sensu{"}) associadas a corpos gran{\'{\i}}ticos da
Prov{\'{\i}}ncia Estan{\'{\i}}fera de Goi{\'a}s, as quais
s{\~a}o controles litol{\'o}gicos de mineraliza{\c{c}}{\~o}es
de Sn, W, Nb-Ta, Li, F, etc. O par{\^a}metro b{\'a}sico que
permitiu a discrimina{\c{c}}{\~a}o destas areas atrav{\'e}s de
imagens orbitais foi o comportamento espectral destes tipos
litol{\'o}gicos e/ou de suas associa{\c{c}}{\~o}es
espec{\'{\i}}ficas de rocha-solo-vegeta{\c{c}}{\~a}o. Em
Rond{\^o}nia, dadas as caracter{\'{\i}}sticas da regi{\~a}o
(profundo manto de intemperismo, coberturas sedimentares
quatern{\'a}rias e floresta tropical), n{\~a}o {\'e}
poss{\'{\i}}vel a discrimina{\c{c}}{\~a}o espectral de
litotipos espec{\'{\i}}ficos. No entanto, mesmo sob essas
condi{\c{c}}{\~o}es, a imagem LANDSAT real{\c{c}}ada por
computador, mostrou os tra{\c{c}}os geol{\'o}gicos principais e
a estrutura{\c{c}}{\~a}o do maci{\c{c}}o gran{\'{\i}}tico
estudado, fei{\c{c}}{\~o}es estas n{\~a}o observadas
atrav{\'e}s de fotografias a{\'e}reas ou de imagens de RADAR. Os
resultados obtidos em Goi{\'a}s e em Rond{\^o}nia mostram que a
utiliza{\c{c}}{\~a}o adequada de imagens de sensoriamento remoto
orbital pode contribuir de maneira efetiva na
orienta{\c{c}}{\~a}o a trabalhos de prospec{\c{c}}{\~a}o
mineral, propiciando economias razo{\'a}veis de tempo e de
recursos na etapa de levantamentos de campo. ABSTRACT: This study
presents a line of procedures for the utilization of orbital
remote sensing data as supporting tools in mineral prospecting
campaigns, exemplified here by studies in granitic bodies of the
Tin Provinces of Goi{\'a}s and Rond{\^o}nia. Initially, a
discussion is made on the role of several interacting parameters
that compose the recorded signal in sensor systems. The
fundamental parameters in the processes of analysis and
interpretation of multispectral data in geology are: the
physiographic characteristics of the region; the geological
characteristics of the target investigated; the role of the
seasonal variables (vegetation cover and illumination conditions);
the characteristics of the sensor system (resolutions); and the
use of computer enhancement techniques applied to digital images.
Taking into consideration the above aspects, the utilization of
LANDSAT multispectral/digital images has allowed the
discrimination of areas with occurrences of greisenized facies
({"}lato sensu{"}) associated to the granitic massifs in the
Goi{\'a}s Tin Province. The greisens are lithological controls of
mineralizations in Sn, W, Nb-Ta, Li, F, and others. The basic
parameter that allowed the discrimination of these areas in
orbital images was the spectral behaviour of these lithological
types and/or of their specific rock-soil-vegetation associations.
In Rond{\^o}nia, due to the particular characteristics of the
region (deep weathering, Quaternary sedimentary covers, and
Tropical Forest), a spectral discrimination of specific lithotypes
is not possible. However, even under these adverse conditions,
computer enhanced LANDSAT images showed the main geological and
structural features of the studied granitic massif. These were not
observed in aerial photography or RADAR images. The results
obtained in Goi{\'a}s and Rond{\^o}nia show that an adequate
utilization of orbital remote sensing images can contribute for
the orientation of field work, yielding reasonable saving in time
and resources during mineral prospecting campaigns.",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)}",
committee = "Amaral, Gilberto and Damasceno, Eduardo Camilher and Bettencourt,
Jorge Silva and Vitorello, Icaro and Ribeiro Filho, Evaristo",
copyholder = "SID/SCD",
englishtitle = "Mineral prospecting bodies in granitic of estaniferas provincial
in Goi{\'a}s and Rond{\^o}nia: a methodological contribution",
label = "1075",
language = "pt",
pages = "171",
targetfile = "publicacao.pdf",
urlaccessdate = "07 maio 2024"
}