MARYLAND GEOLOGICAL SURVEY 13 



PAGE 



The Eocene 164 



The Aquia Formation 164 



The Neocene 165 



The Lafayette Formation 165 



The Pleistocene 169 



The Columbia Group 169 



The Sunderland Formation 170 



The Wicomico Formation 171 



The Talbot Formation 172 



Interpretation of the Geological Eecord 173 



Sedimentary Record of the Crystalline Rocks 173 



Sedimentary Record of the Potomac Group 174 



Sedimentary Record of the Upper Cretaceous 176 



Sedimentary Record of the Aquia Formation 177 



Sedimentary Record of the Lafayette Formation 178 



Sedimentary Record of the Columbia Group 179 



THE MINERAL RESOURCES OF CECIL COUNTY. By Edward Ben- 

 nett Mathews 195 



Introductory 195 



Building-Stone 196 



Port Deposit 196 



Frenchtown 203 



Clay 204 



Brick and Terra Cotta Clays 206 



Stoneware Clays 207 



Fire-Clays 210 



Kaolin 211 



Flint and Feldspar 217 



Iron Ore 218 



Chrome 221 



Gold 222 



Road Materials 223 



Gabbro 224 



Granite 225 



Gravel 225 



Oil 225 



List of Operators in Mineral Products in Cecil County 226 



THE SOILS OF CECIL COUNTY. By Clarence W. Dorsey and Jay 



A. Bonsteel 227 



Introductory 227 



Agricultural Conditions , 227 



Soil Formations 229 



Cecil Loam 230 



Cecil Clay 233 



Cecil Mica-Loam 235 



Conowingo Barrens 236 



Conowingo Clay 238 



