PROTEROZOIC SEDIMENT-HOSTED BASE METAL DEPOSITS OF AFRICAN AND SOUTH AMERICAN CONTINENTS: GEOLOGICAL CORRELATIONS AND METALOGENIC EVOLUTION

WORKSHOP IGCP 450

XI SIMPÓSIO DE GEOLOGIA DE MINAS GERAIS

Belo Horizonte, Brazil, September 27-October 3, 2001

UNESCO/IUGS - SBG-MG

1st CIRCULAR

INTRODUCTION

A Field Workshop is planned to bring together scientists, geologists and other professionals from mineral exploration/mining companies, geological surveys, research institutions and universities around the world, with major participation of professionals working on African and South American sediment hosted base metal deposits. The focus is on the Proterozoic sediment-hosted base metals deposits in general and those of Africa and South America in particular.

OBJECTIVES

In several continental areas, including Africa, the exploration of world class reserves of copper, zinc and lead along with their by-products, e.g. Au, Ag, Pt-Pd, Co, is mainly confined to Meso- and Neoproterozoic basins. Yet a great enigma, namely the paucity of giant base metal deposits in the vast Proterozoic sedimentary basins of South America exists that needs to be addressed. This is all the more intriguing when recent studies on either side of the Atlantic suggest the existence of several common attributes, like sedimentological, structural, geochemical and isotopic characteristics, probably arising form a common geological evolution. We believe that the proposed field workshop should serve as a suitable platform where the leaders in academic institutions, government and mining companies will discuss the many aspects of the Proterozoic sediment-hosted base metals deposits of Western Gondwana. The discussions will not resolve all the outstanding questions but will certainly help identify key problems and suggest the mode of actions that need to be undertaken. Furthermore, the field workshop should help launch national and international collaboration program among people working on similar problems related to base metal deposits, with the active participation of the future leaders, namely post-graduate students.

Four main questions are posed for discussion at this workshop:

1. Which common geological and geotectonical processes can be identified in the Proterozoic metallogenic evolution of the continental areas of Africa and South America?
2. What is the origin of the Proterozoic sediment-hosted base metal deposits in Africa and South America?
3. How appropriate are current criteria in prioritizing potential targets when searching for giant base metal deposits?
4. What strategies should be established to develop adequate exploration models?

VENUE

The Workshop will be held in the historic city of Belo Horizonte, in the State Minas Gerais, Brazil. Belo Horizonte, the first modern Brazilian City to spring from an architect's drawing board, was especially designed for its role as the capital of the state of Minas Gerais. The State of Minas Gerais (may be roughly translated as "'widespread mines") is a geologist's delight and tourist haven.

The field excursion will cover well exposed sections of the Bambuí and Vazante Groups. The mines of Vazante and Morro Agudo are the only Zn-Pb mines hosted by Proterozoic sediments now in production in South America, and the only Zn-Pb mines in Brazil. They have at present about 3.8 million tons of total metal reserves.

THEME AND ORGANIZATION

The general theme is the metallogeny of copper, cobalt, zinc, lead, uranium and the byproducts Au, Ag, Pt-Pd, in the Proterozoic basins of Western Gondwana (Africa and South America).

The agenda is as follows:

1. Oral presentation (including key-note speeches) and poster session followed by discussion (September 24 and September 25, 2001).
2. Five days for field work (September 26 to September 30, 2001).

The invited key-note speakers will review and summarize the present state of knowledge on regions of high exploratory potential in Africa and in South America. The possible metallogenic models will be presented and discussed. Poster presentations should conform to the theme of the meeting and topics covering specific deposits are welcome.

The field excursion will consist of a traverse across geological sections of the Bambuí and Vazante Groups with visits to the Vazante and Morro Agudo Zn-Pb mines.

The official language will be English and no translation services will be made available.

ABSTRACTS

Participants are requested to provide extended abstracts (3 to 5 pages long). A special volume will be published containing full length papers, discussions and conclusions of the meeting.

REGISTRATION

A pre-registration form (attached) should be completed and sent for further information.

FINANCIAL SUPPORT

We are exploring the possibility of offering partial financial support to deserving candidates, especially to students whose abstracts are accepted for presentation.

SPONSORS

ADDRESS FOR CORRESPONDENCE

Prof. Aroldo Misi.

Universidade Federal da Bahia

Centro de Pesquisa em Geofísica e Geologia (CPGG)

Instituto de Geociências

Rua Caetano Moura, 123 (Federação)

40210-340 Salvador-Bahia BRASIL

Fax: 55-71-247-3004

Tel.: 55-71-235-6789/237-0408/9961-8303