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Unformatted text preview: EXAM 2 STUDY GUIDE GEOLOGY 303 WHAT ARE TEKTITES? Small glassy spheres produce by hot impact on earth. Micro-tektites are small liquid drops from major heat impact. WHAT IS IRIDIUM? Dense, hard brittle silvery white transition metal can withstand high temperatures rare crust in the clay layer, found in meteorites WHAT IS SHOCKED QUARTZ? Deformed quartz from a major impact event. When there is a meteorite. IN WHAT WAY ARE TEKTITES, IRIDIUM, AND SHOCKED QUARTZ RELATED TO THE K/T EXTINCTION EVENT? 65 m.y.a Louis and Walter alvarez discovered clay layer in 1980s at the K/T extinction point and found large amount of the rare element iridium. They found that large amounts of iridium were also in meteorites. (this made them realize that the meteorites had came and killed all the dinosaurs and caused the extinction. They started to find other elements like micro- tektites, shock quartz and soot as well) IN WHAT WAY ARE THE DECCAN AND SIBERIAN FLOOD BASALT PROVINCES RELATED TO MASS EXTINCTION EVENTS? The Deccan flood was 65 m.y.a which the basalt covered position of India/Himalayas. Siberian flood was 248 m.y.a. They created basalt flood of lava which caused extinction right after the meteorite, 70% of all life died. WHICH OF THESE IS RELATED TO THE PERMIAN EXTINCTION? (THE GREATEST MASS EXTINCTION EVENT OF ALL TIME. Siberian,95% died. WHICH IS RELATED TO THE K/T EXTINCTION? Deccan WHAT GEOLOGIC TIME UNIT (EON, ERA, PERIOD, EPOCH) REPRESENTS THE GREATEST EXPANSE OF GEOLOGIC TIME? EON WHAT IS THE ERA OF ANCIENT LIFE CALLED? Paleozoic Era 543 mya THE ERA OF MIDDLE LIFE? Mesozoic Era 251 mya THE ERA OF RECENT LIFE? Cenozoic Era 65 mya THE AGE OF THE DINOSAURS? Mesozoic Era THE AGE OF MAMMALS? Cenozoic Era KNOW AND BE ABLE TO DESCRIBE THE IMPACT EVENTS AT TUNGUSKA, CHICXULUB, AND METEOR CRATER. The Tunguska event was in 1908 . The only known major impact of an extraterrestrial object in either historical or archeological time occurred on June 30, 1908 in central Siberia. The huge explosion occurred in the Tunguska River Basin, and the noise was heard up to 1,000 km away. It produced a column of incandescent matter that rose to a height of 20 km. The shock wave from the explosion traveled around the world twice, as registered by seismographs. The shock wave flattened forests like matchsticks in a radial pattern 20 miles from the blast center. Tens of thousands of animals perished and several nomadic settlements vanished from the face of the earth. Although the explosion was initially thought to be a meteorite, its cause remains uncertain. Part of the uncertainty is because the event occurred in an extremely remote area, so that an expedition to the site was not launched until 1921. However, illness and exhaustion prevented that expedition from reaching the explosion site, and it was not until 1927 (19 years later) that the site was finally reached. Although there was ample evidence of massive destruction, unexpectedly, there was no evidence of an impact crater. The lack of a crater led some evidence of an impact crater....
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This note was uploaded on 04/20/2008 for the course GEOLOGY 303 taught by Professor Camp during the Spring '08 term at San Diego State.
- Spring '08