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National Parks formed by Ground Water. Mammoth Cave National Park Petrified Forest National Park. Mammoth Cave National Park Vital Statistics. West Central Kentucky 51,000 acres 82 square miles. Human History. ~2000 BC native american camp 1000 BC to AD 900 Woodlands Culture
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National Parks formed by Ground Water Mammoth Cave National Park Petrified Forest National Park
Mammoth Cave National ParkVital Statistics • West Central Kentucky • 51,000 acres • 82 square miles
Human History • ~2000 BC native american camp • 1000 BC to AD 900 Woodlands Culture • Wooden bowls, gourds, sandals, woven cord, hearths • Collected gypsum • Mummified body, 390 BC • Settlers (re)discovered cave in ~1799 • War of 1812, potassium nitrate was mined • 1815-1837 several changes in ownership • 1837 purchase by Dr. John Croghan $10k • 1837-1859 Stephen Bishop, slave and explorer • 1926 authorized to become NP • 1941 NP Established
Geologic Features • Primary features related to solution of limestone by groundwater • Cave System – Formation of cavities • Initial formation in St. Genevieve Limestone • Rain water absorbs CO2 in atmos. and soil • H2O + CO2 = carbonic acid → dissolves LS • Flow along joints, bedding enlarges to cavity
Geologic Features • Lowering of groundwater level, usually by deepening of rivers. • Cavities drain of water and CaCO3 can be deposited as Dripstone features • Cave Deposits • Travertine (calcite) dripstone • Sediments washed into cave • Breakdown, from collapse of rock into cavity
Types of Flowstone • Stalactites • Stalagmites • Columns & Pillars • Curtains • Flowstone • Helictites
Cave Life • Mammoth Cave blindfish • Eyes degenerate or absent • Lack of body pigmentation • Adaptations to cave life • Blind Crayfish • Cave crickets • Beetles • Worms • Spiders • Bats
Surface Features • Karst Topography • Sinkholes • Disappearing Streams
Geologic History • Devonian – New Albany Shale • Mississippian – marine deposits ~1200ft • Pennsylvanian – shore then river deposits • Permian – Cincinnati Arch uplift and tilting • Mz – erosion
Petrified Forest National Park Vital Statistics • East-central Arizona • ~94,000 acres • 146 square acres
Human History • 500 – 800 Basket Maker Culture • Pit houses • Rectangular houses of stone or adobe • Pueblos, some made of petrified logs • 1400
Human History • 1850’s first explored by Americans • 1878 settlers arrive • 1883 RR went through area now park • 1896 became Forest Reserve • 1898-1900 USGS study • 1906 TR National Monument • 1921 discovery of Phytosaurs • 1931 enlargement • 1933 discovery of Fossil Leaves • 1962 enlargement and upgrade to NP
Geologic Features • Wood petrified by ground water activity • Silicification, preserved by silica replacement • Logs deposited by flood • Volcanic ash • Rainwater percolates and dissolves silica • Above certain concentration silica precipitates • Fills voids first, then replaces cells
Colors • Iron Oxides – (jasper) shades of red/yellow/brown and green • Manganese – (amethyst) purple • Carbon – (“flint”) black • Pure silica – (rock crystal) clear or white • Tiny crystals – (chalcedony) opaque blue to grey • Parallel bands – (agate) several colors
Plant Fossils – over 40 species • Conifers • Araucarioxylon arizonicum – main tree • Up to 120 ft tall, 7 feet dia (3-4 ft average) • Woodworthina Arizonica • Schilderina adamanica • Calamites – 30 feet tall, 1 foot diameter • Ferns – 19 species • Cycads – pineapple base with palm leaves • Flowering Plants – primitive • Plant Fragments • Impressions and carbon films
Fossil Animals • Phytosuars – Triassic Croc-like reptile 25ft • Labyrinthodont – thick-skulled amphibian related to salamanders, 5ft long
Geologic Features (con’t) • Badlands Topography in Painted Desert
Geologic History • Triassic • Moenkopi sandstone • Shinarump congl. • Chinle formation – shale & siltstone plus ash from volcanism in CA and NV • Tr-Jr – transgression of sea – marine seds • K-early Cz Larimide orogeny – uplift of CP • Cz - erosion
Legendary explanations • Result of curse by hungry goddess • Paiute Tribe – shafts of the arrows of the Thunder God, Shinuau • Navajo Tribe – bones of the great giant, Yietso