GEOG 2300 1st Edition Lecture 35Outline of Last Lecture I. Shallow Water WavesII. Human Impacts on the OceanOutline of Current Lecture I. Ways to Help the OceanII. Protecting Aquatic Biodiversity DifficultiesIII. Ocean FloorIV. Earth’s StructureCurrent LectureI. Ways to Help the OceanA. Support organizations protecting the oceanB. Reduce your waste and carbon footprintC. Make wise choices in what you consume (cruises and coastal development)D. Watch what seafood you eatII. Protecting Aquatic Biodiversity DifficultiesA. Rapidly increasing human impactsB. Invisibility of problems/ lack of awarenessC. Lack of legal jurisdictionIII. Ocean FloorA. Continental margin: transition between continents and deep oceans follow a typical form, coastline continental shelf continental slope continentalrise abyssal plainB. Continental shelf: no more than 200 m deep; photic zone, biologically productive; 90% of the fish we eat are from here; minerals and oil extracted here; continental shelves can have ridges, valleys, and submarine canyons, particularly related to past glaciationsC. We know more about the surface of the moon than we do about the ocean floorD. Ocean ridges form a network of submarine volcanic mountains extending through all four oceans along tectonic plate margins, have hydrothermal vents which provide heat and chemicals for organisms to use in chemosynthesisThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.E. Trenches: the deepest parts of the ocean, the deepest one is 11,000 meters deep in the Marianas TrenchF. Abyssal plains: submarine plains covering 40% of the ocean floor, covered by blankets of sedimentG. Islands: part of the ocean floor breaches the surface; many are formed by volcanism; when a volcano rises to the surface, forms a coral reef, then sinks back, the reef continues to grow forming a ring shaped island called an atollH. Coral reefs: shallow, wave-resistant structures formed by calcium carbonate skeletons of tiny animals; host to diverse oceanic communities; coral reefs need sunlight, well-aerated water, temperatures above 20 C, and normal salinityI. Fringing reef: coral attached to coast, Barrier reef: offshoreIV. Earth’s StructureA. Earth has a radius of 6400 km, core radius is 3500 km, core is made of nickel and iron core, causes the magnetic field around earthB. Mantle: largely plastic layer between the core and the crust, ultramafic rock, 2900km thick, temperatures range from 2800 C near to core to 1800 CC. Which best describes the Ring of Fire? The system of active volcanoes that circles much of the Pacific Ocean basinD. Crust: 8 to 40 km deep, contact between crust and upper mantle = Mohorvicic discontinuity (Moho) = change in density, mafic (oceanic ) and felsic (continental)
View Full Document