Distribution and provenance of heavy minerals from recent sediments of Green Lake, North Brazil, revisited
Ribeiro, Anne Caroline S. (Universidade Federal Oeste do Pará (Brasil))
Santos, Livaldo O. (Universidade Federal Oeste do Pará (Brasil))
Cerqueira Dos Santos Junior, Paulo (Universidade Federal do Pará. Instituto de Ciências Naturais e Exatas (Brasil))
Maduro Almeida, Rodolfo (Universidade Federal Oeste do Pará (Brasil))
Mendes, Rodrigo C. (Pontifícia Universidade Católica. Programa de Pós-Graduação em Matemática (Brasil))
Conceição Mendes, Anderson (Universidade Federal do Pará. Instituto de Geociências (Brasil))

Data:	2022
Resum:	Geostatistical and multivariate statistical analyses were applied to heavy mineral data from an Amazonian fluvial-lake system near the Tapajós River mouth to investigate the spatial distribution and source-area of sediments. Twenty-one points were investigated, and the physical characteristics of the Green Lake deepest point were determined. Sand accumulates in the lake margins and mud quantity increases towards the lake center. Heavy mineral assemblage is composed of zircon, tourmaline, kyanite, rutile, staurolite, anatase, sillimanite, garnet, and spinel. Tourmaline, staurolite, and spinel are more abundant in the southeast area of the lake, while kyanite is dominant in the north area and zircon is in the whole lake except in its southeast area. Zircon - tourmaline and zircon - staurolite pairs are negatively correlated (r= -0. 947 and -0. 775, respectively), while tourmaline - staurolite and sillimanite - anatase pairs have a positive correlation (r= 0. 628 and 0. 675, respectively) which indicate different source rock types. Geostatistical analysis grouped the heavy minerals in three grups: Group 1 (tourmaline - staurolite - spinel - kyanite) and Group 2 (garnet - rutile - sillimanite - anatase) related to metamorphic source rocks ranging from medium to high grade, and Group 3 (zircon) related to acid igneous source rocks. The heavy mineral assemblage of Green Lake is analogous to the assemblage of the Alter do Chão Formation, indicating that this formation is the source of sediments of Green Lake.
Drets:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan aquestes es distribueixin sota la mateixa llicència que regula l'obra original i es reconegui l'autoria de l'obra original.
Llengua:	Català
Document:	Article ; recerca ; Versió publicada
Matèria:	Sediment provenance ; Heavy minerals ; Geostatistical modeling ; Green Lake
Publicat a:	Geologica acta, Vol. 20 (2022) , p. 1-14 (Articles) , ISSN 1696-5728

Adreça original: https://raco.cat/index.php/GeologicaActa/article/view/401820
Adreça alternativa: https://revistes.ub.edu/index.php/GEOACTA/article/view/36898
DOI: 10.1344/GeologicaActa2022.20.5

14 p, 2.6 MB

El registre apareix a les col·leccions:
Articles > Articles publicats > Geologica acta
Articles > Articles de recerca