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57 Cards in this Set
- Front
- Back
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Time periods
longest -> shortest |
Eon, Era, Period, Epoch
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Precambrian Eon
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85% of time
4.6 billion yrs - 543 million Scarce and primitive single cell live |
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Phanerozoic Eon
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Cenozoic era
Mesozoic era Paleozoic era 15% of time. Eon of visible life |
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Cenozoic era
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65 mil - present
Age of Mammals Recent life |
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Mesozoic era
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251 mil - 65 mil
Age of Dinosaurs K/T Extinction Middle life |
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Paleozoic era
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543 mil - 251 mil
Permian Extinction Ancient Life |
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Permian Extinction
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95% life perished. Greatest Extinction event. Reptiles survived and grew into dinoasaurs.
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K/T Extinction
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60-70% of life destroyed. Mammals evolved after
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Walter and Louis Alvarez
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K/T Boundary in Italy and found clay contained high concentration of Iridium.
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Iridium
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Ir. Very rare in the concentration of earth. Iron Meteorites have a high concentration of Ir.
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The Clay Layer
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K/T Boundary. Contains: Iridium, Micro-tektites, Shocked Quartz, Soot
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Micro-tektites
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small glassy spheres and the only place there can be produced are in areas of meteorite impact
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Shocked Quartz
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Can only produce it by a major percussive event.
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Sequence and Location of K/T extinction
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Chicxalub Crater on the Yucatan Peninsula
Impact Tsunami Heat Wave Blackout Deep Freeze Global Warming/Acid Rain |
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Deccan Flood Basalt Province
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Same time as K/T. Two globally significant events occurring at the same time. Anti-podal HYPOTHESIS
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Siberian Flood Basalts
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Permian Extinction
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Fullerenes
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Shape of a sphere. Also called Bucky Balls. Can only be formed in antigravity areas
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Meteor Crater
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Arizona. Normal Crater 50k yrs old. Eugene Shoemaker did work here
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Tunguska
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Siberia. 1908. In russian territory didn't make it there for 20 years. 80 million trees fell with no crater. It exploded 8km away from the surface of Earth.
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Eugene Shoemaker
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Started Spacewatch. Catalog all Near Earth Objects NEOs. Amateur Astronomers all over the world helped catalog. Now a branch of Nasa.
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Shoemaker-Levy Comet
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1994 Two impacts on Jupiter one after the other.
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Magma vs Lava
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Magma only exists beneath the surface. We've never seen magma. Magma contains dissolved gasses
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Intrusive vs Extrusive Igneous rock
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Intrusive-coarse
Extrusive-fine grain |
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Volcanic Textures
Crystalline Glassy Vesicular Pyroclastic |
Crystals
opposite crystals bubbly fragmented |
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Magma: Mafic
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Silica: ~50%
In: Gabbro Ex: Basalt Vis: low Exp: low |
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Magma: Intermediate
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Silica: ~60%
In: Diorite Ex: Andersite Vis: Higher Exp: Higher |
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Magma: Felsic
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Silica: ~70%
In: Granite Ex: Rhyolite Vis: Highest Exp: Highest |
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Viscosity
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The property of resistance to flow
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Non-explosive eruption
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Low vis + low gas = basaltic to andesitic
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Explosive
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High vis + High gas = Andesitic to Rhyolitic
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A'a
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Rugged, jagged, spiney. Higher viscosity and breaks up in chucks as it flows. Basalt Composition. Lava Flow
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Pahoehoe
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Smooth billowy and ropey. Basalt Composition. Lava Flow
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Products of Eruptions
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1) Lava Flows
2) Volcanic Gases 3) Pyroclastic materials |
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Lava Tube
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Hot lava resides and the basalt forms all around it. Lava tube will eventually empty out/hollow. Basalt
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Pillow Lava/Basalt
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Lava hits water and breaks up into blobs which accumulate at the ocean floor. Basalt
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Tephra
3 Types? |
Pyroclastic Materials
Ash <2mm widespread Lapilli 2-64mm close by volcano Blocks and Bombs >64mm right near volcano. Spindle Shape solid when the hit the ground |
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Spreading Center Volcanism
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MOR split and generates Basalt
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Subduction zone volcanism
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Andesite (Andes). Ring of Fire -> Pacific Rim
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Hotspot (Intraplate) volcanism
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Hot mantle plums melt and produces basalt
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Parasitic Cone
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small volcano on the flanks of another volcano on the side
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Fumarole
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vent where gasses erupt on the surface on the flanks of the volcano
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Shield Volcanoes
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Flat but very broad. Basalt lava. Mauna Loa.
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Scoria Cones (Cinder)
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Small, very large summit crater, very steep sides. Basalt tephra , (pyroclastic). Little more explosive than shield. Generally erupt once and never again. Small gentle eruptions. Paricutin, Mex
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Stratovolcanoes (Composite Cone)
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Concave upward with very small summit crater. Made up of lava, tephra, andesite. Plinian Eruptions
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Lava Dome
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Lots of material erupting out of a magma chamber. Broadens the summit. Marks the end stage. Like a cork
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Calderas
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Mostly out of stratovolcanoes. Collapse into its own magma Chamber. Crater Lake, OR. Can become a lake.
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Lake Nyos
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Cameroon, Africa. Volcanic Crater filled with water. 1700 people died. Landslide caused bottom waters to come up and wind moved CO2 into village.
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Mount Vesuvius
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Italy 79AD Stratovolcano. Pompeii destroyed by pyroclastic flow and pyroclastic falls. 4000 ppl died.
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Pling the Edler of Rome
Pling the Younger |
Mount Vesuvius
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Herculeneum
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Destroyed by Vesuvius. Pyroclastic Flow.
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Mt Pele
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Martinique 1902. Paris of the West Indes. People forced to stay until election. Pyroclastic flow cover the town of St Pierre. Destroyed every ship except one. 2 survivors of 28k
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Nevado del Ruiz
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Colombia 1985. Lahar. Erupted during thunderstorm where people didn't hear. 22k deaths
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Mt Raineir, WA
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Lahars 5700 and 500 yrs ago
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Voluminous Pyroclastic Sheetflows from what?
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Giant Resurgent Calderas. They overtop the valleys and cover everything.
Valley, NM Long Valley, CA Yellowstone |
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Kilauea
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1983-Present Shield Volcano.
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Direction that Hawaiian and Emperor volcanic chains become older
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West and North = older
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Mt St. Helens
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1980. Earthquake. Giant Landslide. Lateral Blast. Plinian Eruption. Lava dome and another formed in 2004.
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