D Dakota Formation, 12, 51, 53, 56, 94, 97, 105 Dawson Arkose, 60 Dawson Butte, 112 Delcarbon, 97 Democrat, Mt., 21 Denver, 3, 8, 14, 33, 35, 37, 45, 47, 48, 52, 53, 60, 74, 83, 94, 96, 99, 100, 104, 112, 113 Denver Basin, 8, 75, 94, 95 Denver Formation, 60, 62 Devonian, 7, 42-43, 83 Dillon, 104 Dinosaur National Monument, 27, 53, 55 Durango, 25, 28, 35, 47, 58, 78, 85, 102 Dyer Dolomite, 42 E Eagle, 47, 101, 106 Eagle River, 22, 47 Edwards, 22 Elbert, Mt., 22 Eldorado Springs, 109 Elk Mountains, 24, 69 Empire, 1, 78, 81 Englewood, 113 Entrada Sandstone, 51, 93 Environmental geology, 111-113 Eocene, 64 Estes Lake, 103 Estes Park, 69, 104 Evans, Mt., 3, 12 F Fairplay, 78, 84-85 Fairy Cave, 107 Flattop Mountain, 19 Floods, 112-113 Florence, 74, 94 Florissant Fossil Beds National Monument, 65 Fort Carson, 15 Fort Collins, 35, 101, 102 Fountain Formation, 12, 14, 45, 47, 48 Fox Hills Sandstone, 58 Fremont Limestone, 40, 41 Frisco, 21 Front Range, 11-16, 33, 35, 44, 50, 51, 52, 56, 60, 61, 68, 69, 70, 71, 93, 99, 101, 103, 107, 109 Frying Pan River, 105 Fulford, 107 Fulford Cave, 106 G Garden of the Gods, 4, 14, 15, 47, 48 Garfield, Mt., 30 Gas, natural, 1, 28, 75, 94-96 Gems, 75, 102 Gem Village, 102 Georgetown, 78, 81 Gilman, 21 Gilpin County, 78 Glen Eyrie Formation, 44 Glenwood Canyon, 37, 39 Glenwood Springs, 24, 29, 35, 99, 107, 109 Gold, 1, 22, 29, 74, 75, 77-91 Golden, 8, 14, 62, 74, 78, 83, 93, 98, 111 Gold Hill, 1, 74, 78, 79 Gore Creek, 47 Gore Pass, 19, 20 Gore Range, 20-21, 35, 69 Gore Range-Eagle’s Nest Wilderness Area, 20, 21 Granby, 20, 62 Granby Lake, 103 Grand Hogback, 28, 29 Grand Junction, 29, 30, 35, 55 Grand Lake, 12, 69, 103, 104 Grand Mesa, 35, 62 Grand Valley, 25 Gravel, 75, 97-99 Great Sand Dunes National Monument, 17, 18, 73 Green River, 27, 103 Green River Basin, 4 Green River Canyon, 31 Green River Formation, 64, 95-96 Greenhorn Formation, 101 Greenhorn Peak, 16 Groundwater, 76, 105-106 Gunnison, 35 Gunnison, Black Canyon of the, 36, 37, 44, 71, 105 Gunnison River, 35, 36, 37, 105 Gypsum (mineral), 22, 30, 75, 101-102 Gypsum (town), 47, 101 Gypsum Valley, 30, 47, 101 H Hahn’s Peak, 19 Harding Sandstone, 40, 41 Harvard, Mt., 22 Hayden, 96, 97 Hayden Pass, 17 Hermosa Formation, 45, 47 Hidden Valley, 69 Horseshoe Amphitheater, 85 Horseshoe Park, 69 Horsetooth Reservoir, 103 Huerfano Basin, 35, 61 I Ice Age, see Pleistocene Iceberg Lake, 66 Idaho Springs, 14, 78, 80 Idaho Springs Formation, 33, 92 Independence Pass, 22 Iron, 1, 17, 74 Ironton, 78, 88