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Hydrogeology and Simulation of Ground-Water Flow in the Thick Regolith-Fractured Crystalline Rock Aquifer System of Indian Creek

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Hydrogeology and Simulation of Ground-Water Flow in the Thick Regolith-Fractured Crystalline Rock Aquifer System of Indian Creek Hydrogeology and Simulation of Ground-Water Flow in the Thick Regolith-Fractured Crystalline Rock Aquifer System of Indian Creek Basin, North Carolina AVAILABILITY OF BOOKS AND MAPS OF THE US. GEOLOGICAL SURVEY Instructions on ordering publications of the U.S. Geological Survey, along with prices of the last offerings, are given in the current- year issues of the monthly catalog "New Publications of the U.S. Geological Survey." Prices of available U.S. Geological Survey publica­ tions released prior to the current year are listed in the most recent annual "Price and Availability List." Publications that may be listed in various U.S. Geological Survey catalogs (see back inside cover) but not listed in the most recent annual "Price and Availability List" may be no longer available. Order U.S. Geological Survey publications by mail or over the counter from the offices given below. BY MAIL OVER THE COUNTER Books Books and Maps Professional Papers, Bulletins, Water-Supply Papers, Tech­ Books and maps of the U.S. Geological Survey are available niques of Water-Resources Investigations, Circulars, publications over the counter at the following U.S. Geological Survey Earth Sci­ of general interest (such as leaflets, pamphlets, booklets), single ence Information Centers (ESIC's), all of which are authorized copies of Preliminary Determination of Epicenters, and some mis­ agents of the Superintendent of Documents: cellaneous reports, including some of the foregoing series that have gone out of print at the Superintendent of Documents, are obtain­ ANCHORAGE, Alaska Rm. 101, 4230 University Dr. able by mail from LAKEWOOD, Colorado Federal Center, Bldg. 810 U.S. Geological Survey, Information Services MENLO PARK, California Bldg. 3, Rm. 3128, 345 Box 25286, Federal Center, Denver, CO 80225 Middlefield Rd. RESTON, Virginia USGS National Center, Rm. 1C402, Subscriptions to Preliminary Determination of Epicenters can 12201 Sunrise Valley Dr. be obtained ONLY from the SALT LAKE CITY, Utah Federal Bldg., Rm. 8105, 125 Superintendent of Documents South State St. Government Printing Office SPOKANE, Washington U.S. Post Office Bldg., Rm. 135, Washington, DC 20402 West 904 Riverside Ave. WASHINGTON, D.C. Main Interior Bldg., Rm. 2650, 18th (Check or money order must be payable to Superintendent of and C Sts., NW. Documents.) Maps Only Maps Maps may be purchased over the counter at the following For maps, address mail orders to U.S. Geological Survey office: U.S. Geological Survey, Information Services Box 25286, Federal Center, Denver, CO 80225 ROLLA, Missouri 1400 Independence Rd. Chapter C Hydrogeology and Simulation of Ground-Water Flow in the Thick Regolith-Fractured Crystalline Rock Aquifer System of Indian Creek Basin, North Carolina By CHARLES C. DANIEL III, DOUGLAS G. SMITH, and JO L. EIMERS Hydrogeologic conditions, aquifer properties, and recharge rates were characterized to develop a digital ground-water flow model of a 69-square-mile watershed underlain by a thick regolith-fractured crystalline rock aquifer system. U.S. GEOLOGICAL SURVEY WATER-SUPPLY PAPER 2341 GROUND-WATER RESOURCES OF THE PIEDMONT-BLUE RIDGE PROVINCES OF NORTH CAROLINA U.S. DEPARTMENT OF THE INTERIOR BRUCE BABBITT, Secretary U.S. GEOLOGICAL SURVEY Gordon P. Eaton, Director Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government. For sale by the U.S. Geological Survey Information Services Box 25286, Federal Center Denver, CO 80225 Library of Congress Cataloging in Publication Data Daniel, Charles C. Hydrogeology and simulation of ground-water flow in the thick regolith-fractured crystalline rock aquifer system of Indian Creek Basin, North Carolina / by Charles C. Daniel III, Douglas G. Smith, and Jo L. Eimers. p. cm. (U.S. Geological Survey water-supply paper; 2341) (Ground-water resources of the Piedmont-Blue Ridge provinces of North Carolina ; ch. C) Includes bibliographical references. 1. Hydrogeology North Carolina Indian Creek Watershed (Lincoln County) 2. Groundwater flow North Carolina Indian Creek Watershed (Lincoln County) 3. Aquifers North Carolina Indian Creek Watershed (Lincoln County) I. Smith, Douglas G. (Douglas Gray), 1961- . II. Eimers, Jo Leslie. III. Title. IV. Series. V. Series: Ground-water resources of the Piedmont-Blue Ridge provinces of North Carolina ; ch. C. GB1025.N8G76 1989ch.C [GB1025.N8] 553.7'9'097565 s dc21 [551.49'09756'782] 97-11158 CIP ISBN 0-607-87028-1 CONTENTS Abstract.............................................................................................................^ Cl Introduction ................................................................................................................................................................^ C2 Approach ................................................................................................................................................................. C3 Purpose and Scope ................................................................................................................................................... C4 Description of the Study Area .................................................................................................................................. C4 Climate ........................................................................................................................................................^ C6 Previous Investigations............................................................................................................................................. C6 Acknowledgments.................................................................................................................................................... C7 Conceptualization of the Aquifer System........................................................................................................................... C7 Hydrogeologic Framework of the Indian Creek Basin............................................................................................. C9 Ground-Water Movement ........................................................................................................................................ Cll Characterization of Topographic Settings................................................................................................................. C12 Conceptual Hydrogeologic Section.......................................................................................................................... C15 Hydrogeology of the Indian Creek Basin........................................................................................................................... C16 Geology ............................................................................................................................................^ C16 Hydrogeologic Units................................................................................................................................................. CIS Geologic Belts ...................................................................................................................................^^ C19 Structural Fabric and Orientation ............................................................................................................................. C21 Faults .................................................................................................................................................... C22 Folds .....................................................................................................................................................^ C24 Soils.......................................................................................................................................................................... C24 Ground-Water Flow System..................................................................................................................................... C26 Ground-Water Levels...................................................................................................................................... C27 Base Flow ...................................................................................................................................................... C30 Springs............................................................................................................................................................ C36 Water Budget ................................................................................................................................................^ C36 Precipitation..................................................................................................................................^ C37 Recharge-Discharge....................................................................................................................................... C37 Ground-Water Storage.................................................................................................................................... C39 Variation in the Water Budget................................................................................................................................... C41 Hydrogeologic Characteristics ................................................................................................................................. C42 Characteristics of Wells .................................................................................................................................
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