Gamma-ray spectrometry signature of paraná volcanic rocks: Preliminary results

Autor: Nardy, Antonio José Ranalli [UNESP], Moreira, César Augusto [UNESP], Machado, Fábio Braz, Luchetti, Ana Carolina F. [UNESP], Hansen, Marco Antonio Fontoura, Rossini, Adílson José [UNESP], Barbosa, Vladimir [UNESP]
Přispěvatelé: Universidade Estadual Paulista (UNESP), Universidade Federal de São Paulo (UNIFESP), Universidade Federal do Pampa
Jazyk: angličtina
Rok vydání: 2014
Předmět:
Zdroj: Scopus
Repositório Institucional da UNESP
Universidade Estadual Paulista (UNESP)
instacron:UNESP
Popis: Made available in DSpace on 2022-04-29T11:41:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-01-01 The Paraná volcanic rocks (Serra Geral Formation) are characterized by four different types of rocks. The basalts are the most common, and display an integranular texture and dark gray to black color, in massive outcrops. The acid volcanics are represented by aphyric, salt-and-pepper texture, light gray color, named Palmas type (ATP), and by strongly porphyritic, green to brownish gray color, named Chapecó (ATC). The intermediate rocks are represented by light gray, aphyric andesites. Sometimes, it is very difficult to distinguish andesites from ATP rocks or even from basalts, using only petrographic criteria. However, from the geochemical point of view, these rocks are quite different, including the radioactive elements (K, U and Th). In this way the portable gamma-ray spectrometer argued being a useful tool to recognize different rock types with different total gamma-ray signature, such as basalts (4.7 ± 0.8 μRh-1); andesites (7.2 ±1.2 μRh-1), ATC (11.3 ± 1.2 μRh-1) and for ATP (15.4 ± 2.4 μRh-1). Universidade Estadual Paulista, Av. 24A, 1515 Universidade Federal de São Paulo, Rua Prof. Artur Riedel, 275 Universidade Federal do Pampa, Av. Pedro Anunciação s/n Universidade Estadual Paulista, Av. 24A, 1515
Databáze: OpenAIRE