The Buritizal meteorite: classification of a new Brazilian chondrite

Rogerio Nogueira Salaverry,Julio Cezar Mendes,Jérôme Gattacceca,Fernando De Souza Gonçalves Vasques,Maria Elizabeth Zucolotto,Klaus Keil

doi:10.1590/0370-44672016700081

Abstract

Abstract On August 14, 1967, the reporter Saulo Gomes, working at TV Tupi, went to a small city in the State of Sao Paulo called Buritizal to investigate reports of a meteorite fall and write a newspaper report. He actually recovered three fragments of the meteorite at a small farm. In 2014, he donated one of the fragments to the Museu Nacional of the Universidade Federal do Rio de Janeiro (MN/UFRJ). We named this meteorite Buritizal and studied its petrology, geochemistry, magnetic properties and cathodoluminescence with the intent to determine the petrologic classification of the meteorite. In this manner, the Buritizal meteorite is classified as an ordinary chondrite LL 3.2 breccia (as indicated by lithic fragments). The meteorite consists of ~ 2% of metallic Fe,Ni and many well-defined chondrules with ~ 0.8 mm in average diameter. An ultramafic ferromagnesian mineralogy is predominant in the meteorite, represented by olivine, orthopyroxene, clinopyroxene, Fe-Ni alloy, troilite and glass. The total iron content was calculated as 20.88 wt%. Furthermore, the meteorite was classified as weathering grade W1 and shock stage S3. Buritizal is the 25th observed meteorite fall recovered in Brazil, of 70 meteorites known from Brazil. Thus, the study of the Buritizal meteorite is very important and relevant for the Brazilian scientific community.

Highlights

The detailed study of chondrites and their chondrules enables a better understanding of the genesis of the primordial solids in the solar system and their chemical variations and initial dynamic conditions
The meteorite was previously nominated Saulo Gomes meteorite by Zanardo et al (2011), but in this work, the meteorite received a name based on the Nomenclature Committee of the Meteoritical Society regulation, being called Buritizal meteorite
Petrologic, chemical, magnetic and cathodoluminescence studies show that the Buritizal meteorite, from Brazil, is an unequilibrated ordinary chondrite that presents a S3 shock stage and a W1 weathering grade

Summary

Introduction

The detailed study of chondrites and their chondrules enables a better understanding of the genesis of the primordial solids in the solar system and their chemical variations and initial dynamic conditions. Study of chondritic meteorites provides important information on the origin and evolution of the first solids that formed from the solar nebula ~4.56 Ga ago and on the formation and evolution of their asteroidal parent bodies. On August 14, 1967, the reporter Saulo Gomes, working at TV Tupi, went to a small city in the State of São Paulo called Buritizal to investigate a meteorite fall and write a newspaper report. He recovered three fragments of the meteorite at a small farm. The main goal of this paper concerns the Buritizal meteorite classification through analytical methods like petrology, geochemistry, magnetic and cathodoluminescence techniques to classify the meteorite into its chemical and petrologic groups and to determine its weathering grade and shock classification

Methods

Results

Discussion

Conclusion