Observation of the Continental Crust through Drilling I: Proceedings of the International Symposium held in Tarrytown, May 20–25, 1984 (Exploration of the Deep Continental Crust)

Drilling deep into the earth holds a fascination for earth scientists derived in part from the fact that the drill hole is the ultimate test of a hypothesis. When surface exploration methods have been fully uti­ lized and all the geological inferences drawn about the structure be­ neath the surface, we must finally drill to sample directly the third dimension of the crust of the earth. The drill is thus the tool of choice of the energy and minerals re­ sources industry. Because of high cost, drilling has been only sparing­ ly used for solving fundamental problems in the earth sciences. But now, having used the quite sophisticated methodology of exploration geophysics, the exciting structural detail emerging from seismic re­ flection profiling in particular has led several nations to begin a major program of scientific drilling to solve some of the major prGb­ lems in the earth sciences. Hhat is described in this volume are the blueprints for national re­ search programs in France, the Federal Republic of Germany, Japan and the United States. The Soviet Union has already embarked on a major drilling effort, the results of which are soon to be published. Results, of course, are still few, and this first volume is more concerned with the problems to be solved. Front Matter....Pages I-IX Front Matter....Pages 1-1 A U. S. National Continental Scientific Drilling Program....Pages 2-5 German Approaches to Continental Deep Drilling....Pages 6-15 Programme on the Deep Geology of France First Year’s Results....Pages 16-27 Deep Drilling Programs in Belgium....Pages 28-38 Scientific Continental Drilling Project in Japan and Scientific Goals....Pages 39-55 Programme for Deep Drilling in Sweden....Pages 56-65 Front Matter....Pages 67-67 Characterizing Thermal Energy and Mass Transport in Volcanic Caldera Complexes; The Role of Scientific Drilling....Pages 68-87 Models for Volcanic Processes in Long Valley California: Testing by Continental Drilling....Pages 88-96 Front Matter....Pages 97-97 Continental Scientific Drilling to Investigate Brine Evolution and Fluid Circulation in Active Hydrothermal Systems....Pages 98-122 Scientific Drilling to Study the Roots and Margins of Hydrothermal Mineral Systems....Pages 123-129 Front Matter....Pages 131-131 Scientific Drilling to Study Physical Properties and the State of Stress in the Earth’s Crust: An Opportunity for Mid-Crustal Measurements Near the San Andreas Fault....Pages 132-140 Deep-Borehole Techniques for Continuous Monitoring of Crustal Activity and In-Situ Stress Measurement in Japan....Pages 141-152 Front Matter....Pages 153-153 Deep Drilling for Science Constraints/Challenge....Pages 154-155 Geoscience Experiments in Boreholes: Instrumentation....Pages 156-173 Logging Technology for High-Temperature Geothermal Boreholes....Pages 174-181 Use of Geophysical Logs for Quantitative Determination of Fracturing, Alteration, and Lithology in the Upper Oceanic Crust....Pages 182-234 Research and Development Activities in Geothermal Drilling, Completion, and Logging....Pages 235-238 Vertical Electromagnetic Profiling (VEMP)....Pages 239-249 Front Matter....Pages 251-251 Results of Deep Drilling in Austria....Pages 252-272 Deep Drilling Technology for Hot Crystalline Rock....Pages 273-307 Front Matter....Pages 251-251 Observations in an Active Hydrothermal System Through Deep Drilling: Valles Caldera, New Mexico....Pages 308-322 Front Matter....Pages 323-323 Rationale for a Deep Drill Hole Into the Seismically Active Area of the Hohenzollerngraben, Southwestern Germany....Pages 324-342 Rationale for Selecting a Site for an Ultra-Deep Dedicated Scientific Drill Hole in the Southern Appalachians....Pages 343-354 Discovery of Two Proterozoic Granite-Rhyolite Terranes in the Buried Midcontinent Basement: The Case for Shallow Drill Holes....Pages 355-364