title: Radioactivity and gamma-dose rates observed at the Morungaba granites, Southeastern Brazil.
abstract: A ground gamma-ray survey was conducted over part of a large granitic body located near the city of Campinas, eastern São Paulo State, Brazil. The dominant rock types are K-feldspar porphyries-rich granites, porphyritic biotite and hornblend-bearing granites, fine to medium-grained monzogranites and medium to gross grained, biotite and muscovite-bearing monzogranites. The radioactive element distribution reflects local geology, in part re-worked by weathering, and the most radioactive rocks are the K-feldspar-rich granites. The rate of the absorbed dose by the air reflects the integrated effects of the radioactive elements distribution. Most of the observed values vary between 67 and 130 nGy h(-1) and with localised spots with the absorbed dose rate values up to 193 nGy h(-1) and low values of ∼25 nGy h(-1). The mean air absorbed dose rate for the studied area is 77 nGy h(-1).
authors.affiliation: Departamento de Geofísica do Instituto de Astronomia, Geofísica e Ciências Atmosféricas da Universidade de São Paulo, Rua do Matão, 1226, Butantã, São Paulo, SP 05508-090, Brazil.
authors.forename: Fabio de Oliveira
authors.initials: Fde O
authors.lastname: Lucas
authors.forename: Fernando Brenha
authors.initials: FB
authors.lastname: Ribeiro
mesh_terms: D000398:Air Pollution, Radioactive / Q000032:analysis*; D001938:Brazil; D005720:Gamma Rays; D011829:Radiation Dosage; D011834:Radiation Monitoring; D012822:Silicon Dioxide / Q000032:analysis* / Q000528:radiation effects*; D012990:Soil Pollutants, Radioactive / Q000032:analysis*
chemical_list: D012990:Soil Pollutants, Radioactive; C007886:granite; D012822:Silicon Dioxide