TITLEY, S.R., and FRIEHAUF, K.C., Dept. of Geosciences, University of
Arizona, Tucson, AZ 85721
In this century, the community studying economic geology grew from a few hundred geologists working on horseback as the century opened, to a culture in which many thousands of geologists, commonly working in corporate teams, rely heavily on electronic technologies and aircraft at its close. In response to population growth and a corresponding increase in societal expectations, the demand for mined commodities increased exponentially, driving extraordinary changes in the notions of exploration targets, advances in mining, metallurgical, and extractive technologies, and the pursuits of geological missions unheard of at the opening of the century.
'Maturation' of many regions in terms of exploration and development drove shifts in search strategies toward a more global approach, looking at very large areas in 'immature' regions and requiring highly sophisticated techniques. Researchers and exploration geologists now integrate their field observations with modern geochemical studies, computer-aided data analysis, hyperaltitude remote sensing technologies, geophysics, and a host of other innovative tools. This integrated approach helped to bring about fundamental changes in the concepts of ore genesis, such as the models for the formation of syngenetic massive sulfide deposits, porphyry copper deposits, and greenstone gold deposits. The focus of fundamental research in both academic and corporate labs shifted in response to the economics of metal production from smaller, high-grade deposits to larger, bulk-tonnage targets and with changing technology to include more microanalytical techniques. In response to the changing role of public opinion, new aspects of mineral development attracted increasing attention, such as the study of the environmental impacts of mining and the advent of the field of mine reclamation.
In spite of these dramatic changes, however, the basic skills of the ore geologist and the essential need of the applied geologist to observe and interpret outcrop remain the same. And in spite of all of these advances, the fact remains that many of the world's great ore districts in mature exploration regions were discovered in the first half of this century.
abstract number 50148