DOCSLIB.ORG

Depletion and Decline Curve Analysis in Crude Oil Production

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Depletion and Decline Curve Analysis in Crude Oil Production Depletion and Decline Curve Analysis in Crude Oil Production Licentiate thesis Mikael Höök Global Energy Systems Department for Physics and Astronomy, Uppsala University May 2009 2 Abstract Oil is the black blood that runs through the veins of the modern global energy system. While being the dominant source of energy, oil has also brought wealth and power to the western world. Future supply for oil is unsure or even expected to decrease due to limitations imposed by peak oil. Energy is fundamental to all parts of society. The enormous growth and development of society in the last two-hundred years has been driven by rapid increase in the extraction of fossil fuels. In the foresee- able future, the majority of energy will still come from fossil fuels. Consequently, reliable methods for forecasting their production, especially crude oil, are crucial. Forecasting crude oil production can be done in many different ways, but in order to provide realistic outlooks, one must be mindful of the physical laws that affect extraction of hydrocarbons from a reser- voir. Decline curve analysis is a long established tool for developing future outlooks for oil production from an individual well or an entire oilfield. Depletion has a fundamental role in the extraction of finite resources and is one of the driving mechanisms for oil flows within a reservoir. Depletion rate also can be connected to decline curves. Consequently, depletion analysis is a useful tool for analysis and forecasting crude oil production. Based on comprehensive databases with reserve and production data for hundreds of oil fields, it has been possible to identify typical behaviours and properties. Using a combination of depletion and decline rate analysis gives a better tool for describing future oil production on a field-by-field level. Reliable and reasonable forecasts are essential for planning and nec- essary in order to understand likely future world oil production. 3 4 nam et ipsa scientia potestas est 5 6 List of Papers This thesis is based on the following papers, which are referred to in the text by their Roman numerals. I Höök, M., Aleklett, K. (2008) A decline rate study of Norwegian Oil Production. Energy Policy, 36(11):4262–4271 II Höök, M. Söderbergh, B., Jakobsson, K., Aleklett, K. (2009) The evolution of giant oil field production behaviour. Natural Resources Research, 18(1):39-56 III Höök, M., Hirsch, R., Aleklett, K. (2009) Giant oil field decline rates and their influence on world oil production. Energy Policy, 37(6):2262-2272 Reprints were made with permission from the respective publishers. The papers are listed chronologically by date of publication. Authors comments regarding the papers All three papers are published in scientific journals, subjected to a peer-review process with one or more reviewers. Papers I and III are published in Energy Policy, Elsevier’s authoritative journal addressing those issues of energy supply, demand and utilization that confront decision makers, managers, consult- ants, politicians, planners and researchers. The scope of Energy Policy embraces economics, planning, politics, pricing, forecasting, investment, conservation, substitution and environment. Paper II is published in Natural Resources Research, an international journal of the International Asso- ciation of Mathematical Geosciences and American Association of Petroleum Geologists – Energy Min- erals Division devoted to promoting quantitative approaches to mineral resource exploration, assessment, extraction and utilization. Natural Resources Research publishes peer-reviewed, quantitative geoscientific studies on the search for and development of natural resources, including associated environmental, eco- nomical, and risk-related aspects. Natural Resources Research reports cover a wide variety of resources, including coal, water, vegetation, and heavy oil. 7 8 Contents 1. Introduction ............................................................................................................................................. 13 1.1 Thesis disposition ............................................................................................................................. 13 1.2 Introduction to papers....................................................................................................................... 14 2. Theoretical background .......................................................................................................................... 15 2.1 Methodology .................................................................................................................................... 15 2.2 Oil classification ............................................................................................................................... 16 3. The formation of oil ................................................................................................................................ 17 3.1 Development of oil formation theories ............................................................................................ 17 3.2 Oil field formation ............................................................................................................................ 20 3.3 Reservoir fundamentals .................................................................................................................... 21 3.4 Reserves in oil fields ........................................................................................................................ 23 3.5 Ultimate recovery and reserve classifications .................................................................................. 24 3.6 Production fundamentals .................................................................................................................. 24 3.7 Reservoir flow relations ................................................................................................................... 25 4. Oil production modelling ........................................................................................................................ 26 4.1 Decline rate analysis......................................................................................................................... 27 4.1.1 Decline curves .......................................................................................................................... 30 4.2 Depletion rate analysis ..................................................................................................................... 33 4.3 Combining decline and depletion rate analysis ................................................................................ 40 5. Conclusions and outlook ......................................................................................................................... 43 Acknowledgements ..................................................................................................................................... 44 References ................................................................................................................................................... 46 Paper I: A decline rate study of Norwegian oil production ........................................................................ 51 Introduction ............................................................................................................................................ 52 Aim of this study .................................................................................................................................... 52 Methodology .......................................................................................................................................... 52 Distribution of oil ................................................................................................................................... 53 Norwegian giant oil fields ...................................................................................................................... 55 Norwegian dwarf oil fields ..................................................................................................................... 57 Condensate production ........................................................................................................................... 58 Natural Gas Liquids (NGL).................................................................................................................... 58 New field developments ......................................................................................................................... 59 Undiscovered oil .................................................................................................................................... 60 Forecast .................................................................................................................................................. 63 The oil fund of Norway .......................................................................................................................... 64 Conclusion.............................................................................................................................................. 65 Acknowledgments .................................................................................................................................. 66 References .............................................................................................................................................
Load more

Recommended publications
  • Coal and Oil: the Dark Monarchs of Global Energy – Understanding Supply and Extraction Patterns and Their Importance for Futur
    nam et ipsa scientia potestas est List of Papers This thesis is based on the following papers, which are referred to in the text by their Roman numerals. I Höök, M., Aleklett, K. (2008) A decline rate study of Norwe- gian oil production. Energy Policy, 36(11):4262–4271 II Höök, M., Söderbergh, B., Jakobsson, K., Aleklett, K. (2009) The evolution of giant oil field production behaviour. Natural Resources Research, 18(1):39–56 III Höök, M., Hirsch, R., Aleklett, K. (2009) Giant oil field decline rates and their influence on world oil production. Energy Pol- icy, 37(6):2262–2272 IV Jakobsson, K., Söderbergh, B., Höök, M., Aleklett, K. (2009) How reasonable are oil production scenarios from public agen- cies? Energy Policy, 37(11):4809–4818 V Höök M, Söderbergh, B., Aleklett, K. (2009) Future Danish oil and gas export. Energy, 34(11):1826–1834 VI Aleklett K., Höök, M., Jakobsson, K., Lardelli, M., Snowden, S., Söderbergh, B. (2010) The Peak of the Oil Age - analyzing the world oil production Reference Scenario in World Energy Outlook 2008. Energy Policy, 38(3):1398–1414 VII Höök M, Tang, X., Pang, X., Aleklett K. (2010) Development journey and outlook for the Chinese giant oilfields. Petroleum Development and Exploration, 37(2):237–249 VIII Höök, M., Aleklett, K. (2009) Historical trends in American coal production and a possible future outlook. International Journal of Coal Geology, 78(3):201–216 IX Höök, M., Aleklett, K. (2010) Trends in U.S. recoverable coal supply estimates and future production outlooks. Natural Re- sources Research, 19(3):189–208 X Höök, M., Zittel, W., Schindler, J., Aleklett, K.
    [Show full text]
  • Op-Ed Contributor - ‘Peak Oil’ Is a Wa…
    9/4/2009 Op-Ed Contributor - ‘Peak Oil’ Is a Wa… August 25, 2009 OP-ED CONT RIBUT OR ‘Peak Oil’ Is a Waste of Energy By MICHAEL LYNCH Amherst, Mass. REMEMBER “peak oil”? It’s the theory that geological scarcity will at some point make it impossible for global petroleum production to avoid falling, heralding the end of the oil age and, potentially, economic catastrophe. Well, just when we thought that the collapse in oil prices since last summer had put an end to such talk, along comes Fatih Birol, the top economist at the International Energy Agency, to insist that we’ll reach the peak moment in 10 years, a decade sooner than most previous predictions (although a few ardent pessimists believe the moment of no return has already come and gone). Like many Malthusian beliefs, peak oil theory has been promoted by a motivated group of scientists and laymen who base their conclusions on poor analyses of data and misinterpretations of technical material. But because the news media and prominent figures like James Schlesinger, a former secretary of energy, and the oilman T. Boone Pickens have taken peak oil seriously, the public is understandably alarmed. A careful examination of the facts shows that most arguments about peak oil are based on anecdotal information, vague references and ignorance of how the oil industry goes about finding fields and extracting petroleum. And this has been demonstrated over and over again: the founder of the Association for the Study of Peak Oil first claimed in 1989 that the peak had already been reached, and Mr.
    [Show full text]
  • The Oil Depletion Protocol
    1 THE RIMINI PROTOCOL an Oil Depletion Protocol ~ Heading Off Economic Chaos and Political Conflict During the Second Half of the Age of Oil As proposed at the 2003 Pio Manzu Conference, and to be the central theme of the next Pio Manzu Conference, Rimini, Italy on October 28-30, 2005 2 INTRODUCTION Soaring oil prices have drawn attention to the issue of the relative supply and demand for crude oil, which is the World’s premier fuel, having a central place in the modern economy. Knowledge of petroleum geology has made great advances in recent years, such that the conditions under which this resource was formed in Nature are now well understood. In fact, it transpires that the bulk of the World’s current production comes from deposits formed in two brief and exceptional epochs, 90 and 150 million years ago. This fact alone tells us that oil is a finite resource, which in turn means that it is subject to depletion. People ask: Are we running out of oil ? The simple answer is: Yes, we started doing that when we produced the first barrel. But Running Out is not the main issue as the resource will not be finally exhausted for very many years. The much more relevant question is: When will production reach a peak and begin to decline? Depletion: Growth, Peak and Decline Much debate and study has focused on the calculation of the date of peak, but this too misses the main point. It is not an isolated or pronounced peak but merely the highest point on a long and gentle production curve.
    [Show full text]
  • Peak Oil, Peak Energy Mother Nature Bats Last
    Peak Oil, Peak Energy Mother Nature Bats Last Martin Sereno 1 Feb 2011 (orig. talk: Nov 2004) Oil is the Lifeblood of Industrial Civilization • 80 million barrels/day, 1000 barrels/sec, 1 cubic mile/year • highly energy-dense • easy to transport, store • moves goods and people • allows us to fly (there will never be a battery-operated jet plane) • digs huge holes and puts up huge buildings • ballooned our food supply (fertilize, cultivate, irrigate, transport) • our 'stuff' is made from it (iPods to the roads themselves) • we're not "addicted to oil" -- that's like saying a person has an "addiction to blood" Where Oil Comes From • raw organic material for oil (e.g., from plankton) is present in low concentrations in ‘all’ sedimentary rocks, but esp. from two warm periods 90 million and 140 million years ago • temperature rises with depth (radioactivity, Kelvin’s mistake) • oil is generated in rocks heated to 60-120 deg Celsius • rocks at this temp. occur at different depths in different places (N.B.: water depth doesn't count) • oil is ‘cracked’ to natural gas at higher temps (deeper) • abiotic oil from “crystalline basement” is negligible, if it exists • exhausted oil fields do not refill Recoverable Oil • oil must collect in a “trap” to be practically recoverable • a trap is a permeable layer capped by an impermeable one • obvious traps: anticlines, domes (“oil in those hills”) • less obvious traps found by seismic imaging: turned up edges of salt domes, near buried meteorite crater (Mexico) • harder-to-get-at traps: shallow continental shelf (GOM) • even-harder-to-get-at traps: edge continental slope (Macondo, resevoir pressure: 12,000 pounds [6 tons] per sq inch) • essentially no oil in basaltic ocean floor or granitic basement (Used to be!) Second Largest Oilfield Cantarell used to supply 2% of world oil (water) Guzman, A.E.
    [Show full text]
  • The Commons Revisited: the Tragedy Continues
    ARTICLE IN PRESS Energy Policy 35 (2007) 5806–5818 www.elsevier.com/locate/enpol The Commons revisited: The tragedy continues Bob Lloydà Physics Department, Otago University, PO Box 56, Dunedin, Dunedin, Otago, New Zealand Received 20 April 2007; accepted 11 July 2007 Available online 23 August 2007 Abstract Garrett Hardin’s classic paper ‘‘Tragedy of the Commons’’ published in Science in 1968 struck a chord with scientists and non-scientists alike and has continued to provide a key reference point to how a number of ‘‘Commons’’-related problems can be viewed. Hardin’s paper will be in looked at in view of both anthropogenic global warming and peak oil and some of the solutions he posed for the ‘‘population problem’’ applied to the post-peak era. Possible solutions are compared with the Kyoto Protocol for global warming and the Rimini Protocol for peak oil. A carbon-indexed, universal tax on non-renewable energy resources ‘Unitax’ is mooted as a longer-term possibility to overcoming both global warming and the financing of post-peak oil problems. Alas, the process of dealing with global warming and peak oil seems to be falling into the ‘‘no technical solution’’ category that Hardin identified for population. r 2007 Elsevier Ltd. All rights reserved. Keywords: Commons; Peak oil; Global warming 1. The Commons revisited pogenic global warming has been due to the burning of crude oil, in addition to coal and natural gas. Garrett Hardin’s ‘‘Tragedy of the Commons’’, published For those that are not familiar with the ‘‘Tragedy of the nearly 40 years ago in Science (Hardin, 1968), struck a Commons’’ it should be explained that the paper was put chord with scientists and non-scientists alike and has forward as an attempt to show that long-term growth in a continued to provide a key reference point to how a finite world is impossible and that unless some rather number of Commons-related problems can be viewed.
    [Show full text]
  • FULLTEXT01.Pdf
    http://uu.diva-portal.org This is an author produced version of a paper published in Natural Resources Research. This paper has been peer-reviewed but does not include the final publisher proof-corrections or journal pagination. Citation for the published paper: Höök, M., Söderbergh, B., Jakobsson, K. & Aleklett, K. ”The evolution of giant oil field production behaviour” Natural Resources Research, 2009, Vol. 18, Issue 1: 39-56 URL: http://dx.doi.org/10.1007/s11053-009-9087-z Access to the published version may require subscription. Published in Natural Resources Research Volume 18, Number 1, March 2009, Pages 39-56 http://www.springerlink.com/content/142004322x2885nk/ The evolution of giant oil field production behaviour Mikael Höök*, Bengt Söderbergh*, Kristofer Jakobsson*, Kjell Aleklett* Contact e-mail: [email protected] * Uppsala University, Global Energy Systems, Department of physics and astronomy, Box 535, SE-751 21, Uppsala, Sweden http://www.fysast.uu.se/ges Abstract The giant oil fields of the world are only a small fraction of the total number of fields, but their importance is huge. Over 50% of the world oil production came from giants by 2005 and more than haft of the worlds ultimate reserves are found in giants. Based on this it is reasonable to assume that the future development of the giant oil fields will have a significant impact on the world oil supply. In order to better understand the giant fields and their future behaviour one must first understand their history. This study has used a comprehensive database on giant oil fields in order to determine their typical parameters, such as the average decline rate and life-times of giants.
    [Show full text]
  • Norwegian Petroleum Technology a Success Story ISBN 82-7719-051-4 Printing: 2005
    Norwegian Academy of Technological Sciences Offshore Media Group Norwegian Petroleum Technology A success story ISBN 82-7719-051-4 Printing: 2005 Publisher: Norwegian Academy of Technological Sciences (NTVA) in co-operation with Offshore Media Group and INTSOK. Editor: Helge Keilen Journalists: Åse Pauline Thirud Stein Arve Tjelta Webproducer: Erlend Keilen Graphic production: Merkur-Trykk AS Norwegian Academy of Technological Sciences (NTVA) is an independent academy. The objectives of the academy are to: – promote research, education and development within the technological and natural sciences – stimulate international co-operation within the fields of technology and related fields – promote understanding of technology and natural sciences among authorities and the public to the benefit of the Norwegian society and industrial progress in Norway. Offshore Media Group (OMG) is an independent publishing house specialising in oil and energy. OMG was established in 1982 and publishes the magazine Offshore & Energy, two daily news services (www.offshore.no and www.oilport.net) and arranges several petro- leum and energy based conferences. The entire content of this book can be downloaded from www.oilport.net. No part of this publication may be reproduced in any form, in electronic retrieval systems or otherwise, without the prior written permission of the publisher. Publisher address: NTVA Lerchendahl gaard, NO-7491 TRONDHEIM, Norway. Tel: + (47) 73595463 Fax: + (47) 73590830 e-mail: [email protected] Front page illustration: FMC Technologies. Preface In many ways, the Norwegian petroleum industry is an eco- passing $ 160 billion, and political leaders in resource rich nomic and technological fairy tale. In the course of a little oil countries are looking to Norway for inspiration and more than 30 years Norway has developed a petroleum guidance.
    [Show full text]
  • A Comparative History of Oil and Gas Markets and Prices: Is 2020 Just an Extreme Cyclical Event Or an Acceleration of the Energy Transition?
    April 2020 A Comparative History of Oil and Gas Markets and Prices: is 2020 just an extreme cyclical event or an acceleration of the energy transition? Introduction Natural gas markets have gone through an unprecedented transformation. Demand growth for this relatively clean, plentiful, versatile and now relatively cheap fuel has been increasing faster than for other fossil fuels.1 Historically a `poor relation’ of oil, gas is now taking centre stage. New markets, pricing mechanisms and benchmarks are being developed, and it is only natural to be curious about the direction these developments are taking. The oil industry has had a particularly rich and well recorded history, making it potentially useful for comparison. However, oil and gas are very different fuels and compete in different markets. Their paths of evolution will very much depend on what happens in the markets for energy sources with which they compete. Their history is rich with dominant companies, government intervention and cycles of boom and bust. A common denominator of virtually all energy industries is a tendency towards natural monopoly because they have characteristics that make such monopolies common. 2 Energy projects tend to require multibillion – often tens of billions of - investments with long gestation periods, with assets that can only be used for very specific purposes and usually, for very long-time periods. Natural monopolies are generally resolved either by new entrants breaking their integrated market structures or by government regulation. Historically, both have occurred in oil and gas markets.3 As we shall show, new entrants into the oil market in the 1960s led to increased supply at lower prices, and higher royalties, resulting in the collapse of control by the major oil companies.
    [Show full text]
  • Secure Fuels from Domestic Resources ______Profiles of Companies Engaged in Domestic Oil Shale and Tar Sands Resource and Technology Development
    5th Edition Secure Fuels from Domestic Resources ______________________________________________________________________________ Profiles of Companies Engaged in Domestic Oil Shale and Tar Sands Resource and Technology Development Prepared by INTEK, Inc. For the U.S. Department of Energy • Office of Petroleum Reserves Naval Petroleum and Oil Shale Reserves Fifth Edition: September 2011 Note to Readers Regarding the Revised Edition (September 2011) This report was originally prepared for the U.S. Department of Energy in June 2007. The report and its contents have since been revised and updated to reflect changes and progress that have occurred in the domestic oil shale and tar sands industries since the first release and to include profiles of additional companies engaged in oil shale and tar sands resource and technology development. Each of the companies profiled in the original report has been extended the opportunity to update its profile to reflect progress, current activities and future plans. Acknowledgements This report was prepared by INTEK, Inc. for the U.S. Department of Energy, Office of Petroleum Reserves, Naval Petroleum and Oil Shale Reserves (DOE/NPOSR) as a part of the AOC Petroleum Support Services, LLC (AOC- PSS) Contract Number DE-FE0000175 (Task 30). Mr. Khosrow Biglarbigi of INTEK, Inc. served as the Project Manager. AOC-PSS and INTEK, Inc. wish to acknowledge the efforts of representatives of the companies that provided information, drafted revised or reviewed company profiles, or addressed technical issues associated with their companies, technologies, and project efforts. Special recognition is also due to those who directly performed the work on this report. Mr. Peter M. Crawford, Director at INTEK, Inc., served as the principal author of the report.
    [Show full text]
  • Policy 11.Qxd.Qxd
    1755 Massachusetts Ave., NW Suite 700 Washington, D.C. 20036 – USA T: (+1-202) 332-9312 F: (+1-202) 265-9531 E: [email protected] www.aicgs.org 34 AICGS POLICY REPORT OVERCOMING THE LETHARGY: CLIMATE CHANGE, ENERGY SECURITY, AND THE CASE FOR A THIRD INDUSTRIAL Located in Washington, D.C., the American Institute for Contemporary German Studies is an independent, non-profit public policy organization that works REVOLUTION in Germany and the United States to address current and emerging policy challenges. Founded in 1983, the Institute is affiliated with The Johns Hopkins University. The Institute is governed by its own Board of Trustees, which includes prominent German and American leaders from the business, policy, and academic communities. Alexander Ochs Building Knowledge, Insights, and Networks for German-American Relations AMERICAN INSTITUTE FOR CONTEMPORARY GERMAN STUDIES THE JOHNS HOPKINS UNIVERSITY TABLE OF CONTENTS Foreword 3 About the Author 5 The American Institute for Contemporary German Studies strengthens the German-American relation - Chapter 1: Introduction 7 ship in an evolving Europe and changing world. The Institute produces objective and original analyses of Chapter 2: Climate Change and Energy Security: An Analysis of developments and trends in Germany, Europe, and the United States; creates new transatlantic the Challenge 9 networks; and facilitates dialogue among the busi - ness, political, and academic communities to manage Chapter 3: The Third Industrial Revolution: How It Might Look - differences and define and promote common inter - or Is It Already Happening? 17 ests. Chapter 4: Making the Economic Case for Climate Action 23 ©2008 by the American Institute for Contemporary German Studies Chapter 5: A New Era for Transatlantic Cooperation on Energy ISBN 1-933942-12-6 and Climate Change? 35 ADDITIONAL COPIES: Notes 47 Additional Copies of this Policy Report are available for $5.00 to cover postage and handling from the American Institute for Contemporary German Studies, 1755 Massachusetts Avenue, NW, Suite 700, Washington, DC 20036.
    [Show full text]
  • The Politics of Oil
    SYLLABUS PS 399 (CRN 58533): The Politics of Oil Oregon State University, School of Public Policy Spring 2012 (4 credits) Tue & Thur 4-5:50pm, Gilkey 113 Instructor: Tamas Golya Office: Gilkey 300C Office Hours: Tue & Thur 10-11am Phone (during office hours): 541-737-1352 Email: [email protected] “The American Way of Life is not negotiable.” Dick Cheney, Former US Vice President “The species Homo sapiens is not going to become extinct. But the subspecies Petroleum Man most certainly is.” Colin Campbell, Founder of the Association for the Study of Peak Oil Course Description The world’s economic and political developments of the last century played out against the backdrop of a steadily rising supply of energy, especially oil. There are signs that this period of “easy energy” is coming to an end, turning energy into a major economic and political issue in its own right. Peak Oil is a term used by geologists to describe the point in time at which the world’s annual conventional oil production reaches a maximum after which it inevitably declines. Recent evidence suggests that we may pass this peak in this decade. In a broader sense, Peak Oil also stands for the economic, political, and societal effects of a dramatically changing energy supply. These effects will create unprecedented problems, risks and opportunities for policy makers as well as for consumers and businesses. In part due to higher oil prices, the US has begun to catch up to this issue, as evidenced by the founding of a Peak Oil Caucus in the House of Representatives in 2005 and by the demand of former President Bush to find ways to cure “America’s addiction to oil”.
    [Show full text]
  • Anatomy of the 10-Year Cycle in Crude Oil Prices Philip K. Verleger
    Anatomy of the 10-Year Cycle in Crude Oil Prices Philip K. Verleger, Jr. David Mitchell/EnCana Professor of Strategy and International Management Haskayne School of Business University of Calgary, Calgary, Alberta, Canada March 2009 John Wiley & Sons published Twilight in the Desert in 2005. The book’s author, Mat- thew Simmons, contends the world will confront very high and rising oil prices shortly because the capacity of Saudi Arabia, the world’s largest oil producer, is insufficient to meet the future needs of oil consumers. In 448 pages, Simmons extensively discusses his views regarding Saudi Arabia’s future production levels. He asserts that the Saudis have refused to provide details about their reserves, insinuating at several points that the Kingdom’s leaders withhold information to keep the truth from the public. At its core, Simmons’ book is no more than a long exposition of the peak oil theory first espoused by King Hubbert in 1956. Hubbert, it may be recalled, studied the pattern of discovery of super giant oil fields. His review led him to conclude that world productive capacity would peak and then begin to decline. In 1974, Hubbert suggested the global zenith would occur around 1995. Simmons and other adherents to the “peak oil theory” enjoyed great prominence in the first half of 2008. Again and again, one read or heard that the oil price rise was occurring be- cause the flow from world oil reserves had reached or was approaching the maximum while de- mand was still growing. Here’s what one economist wrote just as prices peaked: Until this decade, the capacity to supply oil had been growing just as fast as de- mand, leaving plenty of room to expand production at the first sign of rising pric- es.
    [Show full text]