Transcript Slide 1
Earth has a layered structure. (5150 - 6370 km, solid iron) (2890 - 5150 km) (40 – 2890 km) (0 – 40 km) (Mesosphere) The lithosphere is broken into a mosaic of about a dozen large, rigid plates. Cork Tectonic Plates Water Heat source Convection Currents of the Mantle Convection currents of the mantle drive the movement of the tectonic plates over the Earth’s surface. Convergent Boundary Divergent boundary Convergent Boundary Atlantic plate converges with the Philippine plate. New hazard maps highlight seismic hot spots. American Association for the Advancement of Science Science 2014;345:244-246 Published by AAAS Phillipine plate Three types of plate boundaries: divergent. Convergent, and transform-fault. Mid-atlantic Rift, Iceland Mid-atlantic Rift, Iceland Rift Valley, East Africa Volcanic activity associated with the Rift Valley in astern Africa (Afar in Ethiopia) Phillipine plate Three types of plate boundaries: divergent. Convergent, and transform-fault. Rift Valley Baja, California Movement of continents during the Paleozoic: formation of Pangea. 500 mya 400 mya 250 mya 200 mya 100 mya Evidence for Continental Drift: 1. The jigsaw-puzzle fit of continents on both sides of the ocean and the similarity of geological features on opposite sides of the Atlantic ocean. 2. Match-up of glacier markings of the Southern Continents. 3. Symmetric location of alternating magnetic anomalies parallel with the mid-ocean ridge. 4. Volcanic hotspots and island chains. Africa South America Jigsaw-puzzle fit of continents Matchup of ancient rocks in adjacent regions of continents Glacier markings in rocks. Hawaiian Chain (Hawaiian Islands) Emperor Chain (Emperor Seamounts) Hawaiian Chain Q1. What is the scientific name for the layer of the Earth between 670 and 40 km? Q2. Baja California is separated from mainland Mexico by a _______________ valley. This _____________ boundary forms Dead Valley, CA to the North. Q3. Pangea was completed __________ Mya and started to breakdown _________ Mya. Q4. What feature of the magnetic anomalies found along the floor of the Atlantic Ocean provides best evidence for the presence of a divergent tectonic boundary? _________________________ Q5. When judging the geology of the Yellow Stone hot spot, it is clear that the North America Plate is moving to the _____________________________ ?