Geoquímica do gabro coronítico de Amparo, RJ

Authors

  • Isabel Pereira Ludka Universidade Federal do Rio de Janeiro; Instituto de Geociências; Departamento de Geologia - I; Setor de Geologia de Engenharia e Ambiental
  • Cristina Maria Wiedemann Universidade Federal do Rio de Janeiro; Instituto de Geociências; Departamento de Geologia - I; Setor de Geologia de Engenharia e Ambiental

DOI:

https://doi.org/10.11137/2002_0_44-67

Abstract

The aim of this paper is to present geochemical data and some petrological aspects of the Amparo gabbroic (hyperite) body, located approximately 30 km east of the town, Nova Friburgo, Rio de Janeiro State. Ten samples of these basic rocks were analysed for major, minor and trace elements, and three of these for REE. The data obtained reflect the limited mineralogical range. The contents of the major elements indicate a sub-alkalic tholeiitic magma, as shown by modal analysis, which classified these rocks as an olivine gabbro. Geochemical analysis of the minor, trace and rare-earth elements shows abnormal incompatible enrichment, such as the high LREE, Ba and Sr contents. Similar results for other basic and ultrabasic intrusions are common in this portion of the Ribeira Mobile Belt.

Published

2002-01-01

Issue

Section

Article