300 likes | 559 Views
G130 – Geology of National Parks and Monuments. Instructor: F. Vincent Hernly. G130 – Geology of National Parks Lecture 01 - Introduction. Early National Parks Creation of National Parks Service Introduction to Geology Overview of Rocks Geologic Processes Geologic History.
E N D
G130 – Geology of National Parks and Monuments Instructor: F. Vincent Hernly
G130 – Geology of National ParksLecture 01 - Introduction • Early National Parks • Creation of National Parks Service • Introduction to Geology • Overview of Rocks • Geologic Processes • Geologic History
Creation of First National Parks, 1800’s • 20 APR 1832 Hot Springs Reserve, Arkansas • redesignated Hot Springs NP 1921 • 30 JUN 1864 Yosemite State Park, California • incorporated in Yosemite NP 1906 • 01 MAR 1872 Yellowstone National Park • First Property designated as a National Park • 1875 Mackinac NP, Michigan (abolished 1895) • converted to Mackinac Island State Park, Michigan’s first state park, 1895 • Since 1960 is additionally Mackinac Island National Historic Landmark • 1890 General Grant NP • incorporated in Kings Canyon NP 1940 • 1890 Sequoia NP • 1890 Yosemite NP • incorporated Yosemite State Park 1906 • 1899 Mount Rainier NP
Creation of First National Parks, early 1900’s • Theodore Roosevelt, President, 1901-1909 • 22 MAY 1902Crater Lake NP, Oregon • 01 JUL 1902 Sulphur Springs Reservation, Oklahoma • to Platt NP 1906; to Chickasaw NRA 1976 • 09 JAN 1903Wind Cave NP, South Dakota • 27 APR 1904 Sullys Hill NP, North Dakota • transferred to Ag. Dept. as game preserve 1931
Antiquities Act • 08 JUN 1906 – passed by Congress • Needed to halt vandalism and plundering, esp. of archaeological ruins in the southwest US • Gave President of US power to establish National Monuments (NM) • Congressional act still needed to create National Park (NP)
Proliferation of National Monuments • 08 JUN 1906 – Antiquities Act • 1906 – 4 NM designated (including Petrified Forest, NP in 1962) • 1907 – 5 NM (including Cinder Cone & Lassen Peak, combined as Lassen Volcanic NP 1916) • 1908 – 8 NM (including Grand Canyon, NP in 1919) • 1909 – 6 NM (including Olympic, NP 1938 and Zion, NP 1919) • 1910 to 1916 – 12 more (under Taft and Wilson) • (Including what was to become Acadia NP, 1929) • NP created 1906-1916 • Mesa Verde, Glacier, Rocky Mountain, Abe Lincoln, Hawaii, Lassen Volcanic
Chaos in the National Parks • NP were run by individual Interior Dept Clerks • lack of uniformity and guidelines in the forming and managing of U.S. national parks. • Lack of Coordinated leadership • Led to poor conditions and lack of protection • Desire to increasing tourism to NPs from RR, Auto Clubs, and concessionaires
Creation of the NPS • 25 AUG 1916 – National Parks Act • Created National Park Service • Bureau within Dept. of Interior • Stephen T. Mather – first director • Responsibility over: • 14 NP • 21 NM
NPS Today • 58 National Parks • At least 78 National Monuments • Total of 391 Areas or Units • Questions?
Geology • Scientific Study of the Earth • Physical Geology • Historical Geology • Earth Materials • Elements, Minerals, Rocks
Elements in Earths Crust Of the 92 naturally occurring elements, only 8 consist of 98.5% of all elements in the crust. The other 84 elements are found in the remaining 1.5%.
Minerals • Basic building blocks of the earths crust • Over 2000 known, top 25 make-up over 95% of all minerals in the crust • Quartz, Feldspar, Iron Oxides, Mica, Amphibole, Pyroxene, Olivine, Carbonates, Clay Minerals • Examples in Box 25.2, p. 341, HTT
Rocks • Aggregates of Minerals • Classified in three types, based on origin • Igneous • Sedimentary • Metamorphic • p. 13 in HTT
WeatheringTable 3.1 p. 48 HTT Similar diagram on p. 15, HTT
Igneous Rocks • Form from cooling of molten rock • Magma vs Lava • Classified based on: • Texture – Cooling history • Small crystals – fast cooling • Large crystals – slow cooling • Composition of magma • Granitic Hi silica, low metals, light color • Basaltic low silica, higher metals, dark color • More in Box 25.1, p. 339-340, HTT
Basalt Gabbro
Rhyolite Granite
Melting at convergent plate boundariesMore about Plate Tectonics in Box 2.1, p. 37-39, HTT
Sedimentary Rocks • Form at or very near surface of earth • Cementation of fragments or precipitation • Classification based on: • Texture – transportation history • Small grains – traveled far • Large grains – near source • Composition – source of sediment • Carbonates – marine waters • Silicates – terrestrial source • More in Table 1.1, p. 14, HTT
Sedimentary features • Bedding or Layering • Sedimentary features (ripples, x-beds) • ~75 % of rocks at surface are sedimentary • Contain much evidence for geologic history
Metamorphic Rocks • Formed from transformation of other rocks • Due mainly to: • Increase in temperature • Increase in pressure • Introduction of chemically active fluids • More in Box 24.1, p. 324, HTT
Geologic Agents & ProcessesWill be discussed further as we discuss individual parks • Volcanism (Part IV, p. 506-508; Box 40.1, p. 577, HTT) • Mountain Building (Part V, p. 643-644, HTT) • Weathering (p. 48, HTT, including Table 3.1) • Streams (p. 10-11, HTT; Box 11.1, p. 144, HTT) • Waves (Box 30.2, p 432, HTT) • Glaciers (Part III, p. 290-293, HTT) • Wind • Groundwater (Part II, p. 189, HTT; Box 14.1, p. 196 HTT)
Geologic Time – Basic Principles • Principle of Uniformitarianism • Principle of Original Horizontality • Principle of Lateral Continuity • Principle of Superposition • Principle of Cross-Cutting Relationships
Geologic Time Scale • Time is divided into intervals • Eons, Eras, Periods, Epoch • Divisions are based on Fossils • Principle of Faunal Succession • Age is based on relative dating • Since ~1900, numerical ages have been determined based on radiometric dating • Time scale can be found inside front cover of HTT