Stratabound Ore Deposits In The Andes

Based on an international seminar, held Sept. 1986 in Cuzco, Peru, sponsored by Multiciencias (Peru) and Unesco.

The present volume Stratabound Ore Deposits in the Andes has its roots in an international seminar on stratabound ore deposits which took place in September 1986 in Cusco, Peru, sponsored by Multi ciencias (Peru) and UNESCO. During this seminar it became clear that the amount and quality of research done on stratabound ore deposits in the Andes required a synthesis. Researchers in industry and government as well as in academia, including many which had participated at the Cusco Seminar, were invited to contribute. The answer was extremely positive, confirming the idea that a book expressing the state of the art of the study of stratabound ore deposits in the Andes was long overdue. As editors we sought to give maximum coverage to the present knowledge, yet keeping the length, and thereby the price, within rea sonable limits. The book contains three types of contributions. In the first part the reader will find review papers focusing on ( 1) the geologic framework (Frutos), (2) the metallogenesis in Andean countries including also types of deposits differing from those of stratabound nature (Cardozo and Cedillo, Oyarzun), and (3) an in troductory overview of the stratabound ore deposits in the Andes, emphasizing their geotectonic position as a classification tool (Font bote).

The Joint 6th Biennial SGA-SEG Meeting was held in Krakow in August 2001. This volume contains 274 extended abstracts, grouped thematically under 18 session titles covering topics such as lead-zinc deposits; metamorphism affecting mineral deposits; and the environmental aspects of mining.

Geophysical data relating the dynamic processes of plate motion and subduction to Andean orogenesis are interpreted in terms of a new model for magmatic and tectonic development of the central Andes. The model is based on changing subduction geometry - from normal to flat to normal - and the attendant magmatic and tectonic effects of slab dewatering, continental lithospheric hydration, and asthenospheric flow during closing and opening of the subduction zone mantle wedge.

The problem of time-and strata-bound formation of ore deposits has during the past decade become one of the most debated topics in cur rent international discussion. Due to the amazing results of modern mineral exploration and world-wide geophysical research, the mutual relationship between the complex geological history pf a crustal seg ment and the development of distinct metallogenic provinces (ore belts) has received much interest. Reviewing the earth's history in this light one can now recognize metallogenic epochs even of global range which document the existence of world-wide time-bound ore enrich ments. The knowledge of these metallogenetic processes has been growing step by step for several decades. It began with simple observations and sceptic interpretations, which at first threw heretical spot lights on to the edifices of the prevailing theories on granitic differentiation as the favoured source of ore deposits. It was obvious that the new ideas at first referred to ore enrichments in sedimentary sequences, nowadays summarized under the term strata-bound, and mainly interpreted as stratiform or sedimentary ore deposits. Moreover, the modern term "strata-bound" also includes ore mineralizations which are bound to distinct units of layered (intrusive or extrusive) igneous complexes as a general descriptive term without genetical restriction! Albert Maucher is one of the representatives of the initial era who discussed these genetical questions critically in the decade before the 2nd World War.