COMMISSION OF MARYLAND GEOLOGICAL SURVEY S. JAMES CAMPBELL Towson RICHARD W. COOPER Salisbury JOHN C. GEYER Baltimore ROBERT C. HARVEY Frostburg M. GORDON WOLMAN Baltimore PREFACE In 1906 the Maryland Geological Survey published a report on "The Physical Features of Maryland", which was mainly an account of the geology and min- eral resources of the State. It included a brief outline of the geography, a more extended description of the physiography, and chapters on the soils, climate, hydrography, terrestrial magnetism and forestry. In 1918 the Survey published a report on "The Geography of Maryland", which covered the same fields as the earlier report, but gave only a brief outline of the geology and added chap- ters on the economic geography of the State. Both of these reports are now out of print. Because of the close relationship of geography and geology and the overlap in subject matter, the two reports were revised and combined into a single volume and published in 1957 as Bulletin 19 of the Department of Geology, Mines and Water Resources. The Bulletin has been subsequently reprinted in 1961 and 1966. Some revisions in statistical data were made in the 1961 and 1968 reprints. Certain sections of the Bulletin were extensively revised by Dr. Jona- than Edwards in this 1974 reprint. The Introduction, Mineral Resources, Soils and Agriculture, Seafood Industries, Commerce and Transportation and Manu- facturing chapters of the book have received the most revision and updating. The chapter on Geology and Physiography was not revised. This report has been used extensively in the schools of the State, and the combination of Geology and Geography in one volume allows greater latitude in adapting it to use as a reference or textbook at various school levels. Bulletin 19 is a comprehensive compendium of the physical features, natural resources, and economic geography of Maryland. Many sources of information were used in the initial compilation and the subsequent revisions. Much of the information was extracted from the various publications of the Maryland Geological Survey (or its predecessor organization, the Department of Geology, Mines and Water Resources). Grateful acknowledgement is made to the many federal, state and local government organizations, without whose cooperation this report could not have been made as complete and authentic. Supplementary publications useful to the reader desiring more detailed in- formation are the County Reports, and Bulletins and Reports of Investigations of the Maryland Geological Survey. Particularly useful in better understanding the sections on Geology and Physiography, and Mineral Resources is a colored Geologic Map of Maryland published by the Survey in 1968 at a scale of one inch equals four miles. Larger scale geologic and topographic maps of the individual counties of Maryland are also available. Kenneth N. Weaver, Director Maryland Geological Survey The Johns Hopkins University Baltimore, Maryland 21218 V CONTENTS Preface v Geography and Geology of Maryland 1 Introduction 1 Location 1 Size 1 Boundaries 2 Population 5 Counties 5 History 9 State government 13 The Federal government in Maryland 15 Education 17 Research and development 18 Climate of Maryland 19 Temperature 19 Precipitation 27 Drought 30 Winds 33 Geology and physiography 36 Coastal Plain province 39 Physiography of the Coastal Plain area 39 Geology of the Coastal Plain area 45 Crystalline basement 45 Sedimentary rocks 47 Triassic 47 Cretaceous 47 Paleocene 49 Eocene 49 Oligocene 50 Miocene 51 Pliocene (?) and Pliestocene 53 Piedmont province 56 Physiography of the Piedmont area 56 Eastern division of the Piedmont province 56 Western division of the Piedmont province 56 Geology of the Piedmont area 57 Geologic formations of the eastern division of the Piedmont province 57 Baltimore gneiss 57 Hartley augen gneiss 59 Glenarm series 59 Setters quartzite 59 Cockeysville marble 59 Wissahickon formation 60 Peters Creek formation 60 Cardiff conglomerate and Peach Bottom slate 61 Granitic and gabbroic rocks 61 Gabbro and meta-gabbro 61 vii viii Geography and Geology of Maryland Pyroxcnite, peridotite, serpentine and soapstone 62 Granitic rocks 63 Pegmatite 63 Diabase dikes 63 Geologic formations of the western division of the Piedmont province 64 Wakefield marble 65 Volcanic rocks 65 Sugarloaf Mountain quartzite 65 Wissahickon formation 66 Marburg schist 66 Limestones of the Frederick valley 66 Newark group 66 Diabase dikes 67 Appalachian province 68 Physiography of the Appalachian area 68 Blue Ridge district 68 Greater Appalachian valley 69 Allegheny plateau 71 Geologic formations of the Appalachian area 71 Pre-Cambrian formations 71 Granitic gneisses 71 Catoctin metavolcanics 72 Loudoun formation 72 We vert on quartzite 72 Harpers formation 73 Age of the Loudoun, Weverton and Harpers formations 73 Cambrian formations 74 Antietam sandstone 74 Tomstown dolomite 74 Waynesboro formation 74 Elbrook limestone 75 Conococheague limestone 75 Ordovician formations 76 Beekmantown group 76 St. Paul group 77 Chambersburg limestone 78 Martinsburg shale 78 Juniata formation 79 Silurian formations 79 Medinan Series 79 Tuscarora sandstone 79 Niagaran series 80 Rose Hill formation 80 Keefer sandstone 80 McKenzie formation 81 Cayugan series 81 Bloomsburg formation 81 Wills Creek formation 81 Tonoloway limestone 82 Keyser limestone 82 Lower Devonian formations 83 Contents ix Helderberg group g j Coeymans formation g3 New Scotland formation g4 Becraft formation Oriskany group g4 Shriver chert g5 Ridgeley sandstone gi; Huntersville chert g5 Middle Devonian formations gg Romney formation g5 Onondaga shale member gg Marcellus black shale member gy Hamilton member gj "Tully" limestone g7 Upper Devonian formations gg Jennings formation gg Burkett shale member g9 Woodmont shale member g9 Parkhead sandstone member gg Chemung sandstone member 90 Hampshire formation 9q Mississippian formations 9] Pocono formation 9] Rockwell member 9j Purslane sandstone member. , 9] Undifferentiated Pocono 92 Greenbrier formation 92 Loyalhanna member 92 Mauch Chunk formation 93 Pennsylvanian formations 93 Pottsville formation 94 Allegheny formation 95 Conemaugh formation 95 Lower member 95 Upper member 97 Monongahela formation 9g Permian formations 9g Dunkard group 9g Geologic history of the Piedmont and Appalachian provinces 98 The Appalachian geosyncline 9g Origin of the present topography ]04 Mineral resources F-is 2 Coal 105 Natural gas 109 Metallic mineral products Uj Iron ores Iron mineral pigments ]]3 Gold and silver j ]3 Copper 114 Lead and zinc x Geography and Geology of Maryland Chromium 115 Manganese, molybdenum, and titanium 115 Non-metallic mineral products 116 Stone 116 Building and ornamental stone 116 Granite 116 Gneiss 118 Gabbro 118 Marble and limestone 118 Limestone breccia 120 Serpentine 120 Quartzite 121 Sandstone 122 Slate 122 Crushed or broken stone 123 Limestone used for cement and lime manufacture 123 Sand and gravel 124 Lightweight aggregate 124 Ceramic mineral products 125 Common brick clay 125 Pottery or ball clay 126 Fire clay 126 Kaolin 127 Feldspar 127 Flint (quartz) 128 Miscellaneous mineral products 128 Talc and soapstone 128 Diatomaceous earth 129 Asbestos 129 Mica 129 Barite 130 Marls 130 Water resources 1^1 Surface-water resources 131 Ground-water resources 134 Occurrence and nature of ground water 134 Ground waters of the Coastal Plain province -37 Ground waters of the Piedmont province 139 Ground waters of the Appalachian province 141 Eastern part 141 Western part 142 Magnitude of Maryland's water resources 142 Soils and Agriculture 145 Origin and types of soils 145 Land capability classification 147 Soil group classification 149 Maryland farms and farm lands 150 Types of farming in Maryland 151 Poultry production 151 Dairying 154 Livestock 154 Contents xi Tobacco 154 Truck crops 156 Grains 157 Soybeans 158 Fruit 158 Trends in Maryland agriculture 159 Flora of Maryland 161 Smaller plants 162 Trees and larger shrubs 163 Forest fires 169 Insects and diseases 169 Grazing 171 Timber Resources 171 Maryland's Wood Industries 172 Forest Policy and Management 173 Fauna of Maryland 174 Game mammals and birds 174 Predatory birds 175 Song birds 175 Reptiles and amphibians 175 Fish : 176 Sea food industries 178 Oyster industry 178 Clam industry 179 Crab industry 179 Fish industry 180 Minor sea-food industries 180 Effect of Tropical Storm Agnes in 1972 181 Commerce and Transportation 182 Port of Baltimore 182 Other Maryland ports 183 Chesapeake and Delaware canal 184 Early intrastate transportation 184 National road 184 Chesapeake and Ohio canal and Baltimore and Ohio railroad 185 Modern roads and highways 185 Railroads 187 Airports 188 Manufacturing 189 Development of manufacturing in Maryland 189 Maryland industrial areas 189 Baltimore metropolitan area 190 Western Maryland 192 Eastern Shore 192 Eastern Piedmont 192 Washington suburban area 193 Southern Maryland 193 Description of plates 1 to 11 194 Plates 199 Index 229 xii Geography and Geology of Maryland TABLES 1. Population of Maryland in 1970 in Basis of Origin 7 2. Growth of Population in Maryland Counties, 1960 to 1970 7 3. Maryland Counties with Date of Formation, Origin of Name, and Area 8 4. Temperature Rccords (in degrees Fahrenheit) for Maryland Localities and the Dis- trict of Columbia 25 5. Frequency of Temperature and Precipitation Extremes at Baltimore 27 6. Precipitation Records for Maryland Localities and the District of Columbia 30 7. Geologic Formations of the Maryland Physiographic Provinces 40 8. Maryland Mineral Production in 1972 106 9. Range in Dissolved Solids, Hardness, Iron, and pH in Ground Water from Coastal Plain Formations 140 10. Consumptive Use of Fresh Water in Maryland 143 11. Percent of Farmland, Number of Farms, and Average Size of Farms in Maryland ("ounties, 1969 152 12. Types of Farms in Maryland Counties, 1969 152 13. Dairy and Poultry Statistics for Maryland Counties, 1969 155 14. Livestock Raised in Maryland Counties, 1969 155 15. Acreage in Pastureland and Planted in Animal Feeds in Maryland Counties, 1969 . 156 16. Acreage and Value in Truck Crops in 1972 157 17. Acreage Planted in Cereal Grains in Maryland Counties, 1969 158 18.