FORECASTING DEPLETION CONTENTS Illustrations of depletion Strategic importance of depletion forecasting Major factors in depletion forecasting Definitions of resources, reserves, depletion, and other terms The relation of technology to depletion Economic technology Provident technology Limits of technology Historical sketch of nonrenewable-rescurce use Importance of nonrenewable resources to an industrial society Geologic and geographic factors Evolving efficiencies of nonrenewable-resource exploitation Methods of calculating ultimate availability of nonrenewable resources The problem The economic method The geologic-analogy method Page 1 5 7 8 12 16 16 16 17 18 21 24 28 28 The exploitation-history method Analysis of these methods Recent history of U.S. production, consumption and importation of nonrenewable resources Depletion forecasts for the problem resources Natural gas Petroleum - The alloy metals -- Antimony, chromium, cobalt Manganese Fluorspar 75 Figure 1 2 3 4 TABLE OF ILLUSTRATIONS iii Production of the Comstock Lode, Nevada, showing three Depletion history of Lake Superior district (U.S.) iron Depletion history of crude oil in the United States in- Man's use of energy through the millennia, emphasizing Page 3 4 6 5 Energy input shares, U.S. economy, 1850-1970 6 Relation of energy consumption to GNP for selected 23 7 Net work profit from the natural subsidy in coal depends 26 8 A. Sketch through earth's crust, showing discontinuous B. Upward-branching vein pattern typical of many metallic ore deposits Approximate flow of energy through the United States 38 12 Cost of oil and gas wells drilled in Texas, by total 41 13 Proved and potential natural gas reserves in Texas by |