278 ANNUAL REPORT SMITHSONIAN INSTITUTION, 19 3 9 



ALPHABETICAL LIST OF GEOLOGICAL ITEMS NOTED IN THE 

 NATIONAL ZOOLOGICAL PARK 



Abrasion. 



Accessory minerals. 



Acid rocks. 



Acid soil. 



Action of life on rocks. 



Alluvial plain. 



Alluvium. 



Amethyst. 



Angle of rest. 



Angular unconformity. 



Anticline. 



Aquifers. 



Artifacts. 



Atlantic Coast Plain. 



Auriferous quartz veins. 



Badlands. 



Basal conglomerate. 



Base level. 



Basic rocks. 



Biotite mica. 



Boulders. 



Casts. 



Chalcedony. 



Chemical decomposition. 



Chert. 



Citrine. 



elastics. 



Clay. 



Coal. 



Coastal plain. 



Cobbles. 



Concretions. 



Conglomerate. 



Contact metamorphism. 



Continental deposits. 



Corrasion. 



Correlation of strata. 



Corrosion. 



Creep of soil. 



Crystalline rocks. 



Delta. 



Deposition in lakes. 



Diastrophism. 



Diatoms. 



Differential weathering. 



Dikes. 



Dinosaur gravels. 



Diorite. 



Dip. 



Eolian sandstone. 



Erosion. 



Essential minerals. 



Even sky line. 



Exfoliation. 



Fall line. 



Falls and rapids. 



Fault. 



Fault line. 



Fault plane. 



Fauna. 



Feldspar. 



Flint 



Flood plain. 



Flora. 



Fold. 



Footvrall. 



Fossils. 



Fresh-water deposits. 



Frost action. 



Gabbro. 



Garnets. 



Geologic formation. 



Geologic section. 



Gneiss. 



Gold. 



Gouge. 



Granite. 



Granite gneiss. 



Gravel. 



Ground water. 



Guide fossils. 



Hanging wall. 



Heave. 



Historical geology. 



Hornblende. 



Hydration. 



Igneous intrusion. 



Igneous rocks. 



Indian quarries. 



Intrusive rock. 



Jasper. 



Joint blocks. 



Joint plane. 



Kaolin. 



Levees. 



Limonite. 



Loess. 



Magma. 



Marine deposits. 



Marine sandstone. 



Master joints. 



Mechanical disintegration, 



Metamorphic rocks. 



Meteoric water. 



Mica schist. 



Milky quartz. 



Molds. 



Muscovite mica. 



Outcrops. 



Oxidation. 



Peat. 



Pebbles. 



Pegmatite dike. 



Peneplane. 



Petrifaction. 



Petrified trees. 



Physical geology. 



Physiographic provinces. 



Piedmont Plateau. 



Placer mining. 



Plains. 



Potholes. 



Primary minerals. 



Pyrite. 



Quartzite. 



Residual boulders. 



Residual soil. 



Ripple marks. 



Rock crystal. 



Rock glacier. 



Rock mantle. 



Rose quartz. 



Run-off. 



Saccharoidal sandstone. 



Sand. 



Sand bars. 



Sandstone. 



Schistosity. 



Schists. 



Sedimentary rocks. 



Sediments. 



Shales. 



Siderite. 



Silt 



Slickensides. 



Smoky quartz. 



Soapstone. 



Soils. 



Solution. 



Spheroidal weathering. 



