Talus—a mass of rock debris commonly on slopes or at the base of a steep mountain or cliff. Topography—the configuration of a land surface. Unconformity—a break in the sequence of rock formations which separates younger strata from older ones; caused primarily by removal of older rocks by erosion before those of a later sequence were laid down. Weathering—any natural process, mechanical or chemical, whereby rocks are disintegrated or decomposed into smaller particles and ultimately into clay and soil. Index A abrasion: 30 Adair, John: 6 “Age of Mammals”: 27 alabaster: 17 ancient man in Palo Duro Canyon: 3 anhydrite: 18 anticlines: 18 Apaches: 1, 3 aquifer: 26 Arapahos: 3 Archeozoic rocks: 13 B “blow sand”: 28 bottom load: 29 Brazos River: 8 _Buettneria_: 22, 23, 24 C calcite: 22 caliche: 26 camels: 27 camping and picnicking: 43 Canyon, Texas: 45 Capitol Peak: 1, 18, 19, 31, 40, 42 Carboniferous Period: 16 Catarina Cave: 19, 37, 38 chemical weathering: 30 chert: 26 Cheyennes: 3 Civilian Conservation Corps: 8 Colorado River: 8 _comancheros_: 6, 46 Comanches: 1, 3 concretions: 22 conglomerate: 24 coprolites: 22 Coronado, Francisco Vasquez de: 3 Coronado Lodge: 1, 21, 26, 33, 34 “Cow Cabins”: 41 cross-bedding: 19, 20 cross-stratification: 19 D decomposition: 30 Devil’s Slide: 19, 40, 44 Devil’s Tombstone: 40 differential erosion: 31, 41 disintegration: 30 dugout, Col. Charles Goodnight’s: 39, 40 E earth history: 10-12 Eastern Caprock Escarpment: 8 erosion, differential: 31, 41 F flash floods: 29 fluorescence: 26 fluvial sediments: 24 Fortress Cliff: 1, 40, 42 fossils: 10 frost wedging: 30 G geodes: 22 geologic column: 12 geologic time scale: 11, 12 geomorphologist: 29 Goodnight, Colonel Charles: 1, 39, 40 gypsum: 17 H Harper, Mrs. Ples: 35 hematite: 22 Hester, W. A.: 1 High Plains: 8 hiking: 43 history of park: 3-8 “hoodoos”: 23, 31 Horn, Ron: 35 horseback riding: 43 horses: 27 hydration: 18, 31 hydraulic action: 30 I Ice Age: 3 igneous rocks: 10 Indian campground: 39 Indians of the Plains: 3 J JA Ranch: 6 K Kiowas: 1, 3 L Lighthouse, The: 23, 25, 39, 41 Little Sunday Canyon: 39 Llano Estacado: 8