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A geologic reconnaissance of the Cycladic blueschist belt, Greece A geologic reconnaissance of the Cycladic blueschist belt, Greece

The Cycladic blueschist belt consists of two distinctive segments separated by a broad zone of superposed granitic and high-temperature metamorphic rocks. The northern segment contains early metamorphic fold axes and parallel glaucophane lineations that trend ∼060° with a progressive increase in metamorphism toward the southeast. The southern segment contains similar fold axes and...
Authors
M. Clark Blake, Michel Bonneau, Jacques Geyssant, J.R. Kienast, Claude Lepvrier, Henri Maluski, Dimitrios Papanikolaou

Geologic mapping of Kentucky: A history and evaluation of the Kentucky Geological Survey--U.S. Geological Survey Mapping Program, 1960-1978 Geologic mapping of Kentucky: A history and evaluation of the Kentucky Geological Survey--U.S. Geological Survey Mapping Program, 1960-1978

In 1960, the U.S. Geological Survey and the Kentucky Geological Survey began a program to map the State geologically at a scale of 1:24,000 and to publish the maps as 707 U.S. Geological Survey Geologic Quadrangle Maps. Fieldwork was completed by the spring of 1977, and all maps were published by December 1978. Geologic mapping of the State was proposed by the Kentucky Society of...
Authors
Earle Rupert Cressman, Martin C. Noger

Magnetic effects of maghemitization of oceanic crust Magnetic effects of maghemitization of oceanic crust

Both theoretical considerations and available experimental results indicate that magnetic effects of maghemitization are strongly dependent on the grain size of the originally unoxidized titanomagnetite. Maghemitization of single‐domain titanomagnetite results in a decrease in coercivity, an increase in susceptibility, and a large decrease in Q ratio. Maghemitization of multidomain...
Authors
M. Prevot, A. Lecaille, Edward A. Mankinen

Physical factors that could restrict mineral supply Physical factors that could restrict mineral supply

Stages in the metal supply process are affected by each of the following physical (geologic) factors: (1) geographic distribution of concentrations of potential ore minerals, (2) depth of these concentrations, (3) mineralogy, (4) grain size of the minerals, and (5) grade and (6) tonnages of the concentrations. For mineral deposits of each type in each geologic and political environment...
Authors
John H. DeYoung, Donald A. Singer
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