Introduction to Oceanography - Assignment Example

Geol144 Introduction to Oceanography GEOL144 INTRODUCTION TO OCEANOGRAPHY Question All Hawaiian Islands originated from volcanic eruptions; their formations are also on the middle of Pacific Ocean. The theory that best describes the formation of Hawaiian Islands is the “hotspot theory”. This particular theory was stated by a Canadian geophysicist, J. Tuzo Wilson in the year 1963. One of the reasons why the “big island” of Hawaii is the largest is because under it lays the hot spot which feeds it with magma filling its active volcanoes Mauna and Kilauea. The Loihi volcano also forms magma which feeds the hot spot of the southeastern edge. The other Islands in Hawaii that are northwestward do not fall on top of the hot spot, they cannot be fed with any magma and so they are not active volcanoes. The “Big Island” is also the largest because the volcano eruptions have occurred recently on the southern parts of Hawaii compared to the northern part which its eruption occurred long time ago. The hotspot theory proved that Kauai, Oahu, Molokai and Maui have never erupted for the last one million to five million years. The southeastern island is also the youngest this is an indication that it still an active volcano has magma beneath it (Garrison, 2009). Question # 2 A hydrothermal vent or black smokers are geysers coming from under the seafloor which continuously discharge very hot and enriched water which in turn support the lives of a variety of organisms. The most common place to get hydrothermal vents is in the Atlantic and the Pacific oceans. The average depth to which a hydrothermal vent can be found is about 7,000 ft in a seafloor that spreads through the Mid-Ocean Ridge system. The formation of hydrothermal vent starts from Mid-Ocean Ridge, here the parts that form the earth crust which are gigantic plates move apart at the same time it creates cracks and also some crevices along the ocean floor. The seawater that is above the openings created which were created by the cracks is sipped in. Inside the cracks they are heated by magma and molten rock which lie underneath the earth’s crust. When the sea water becomes heated up, it rises up seeking a path through the opening on to the seafloor. At the time i8n which the vent water is bursting out back in the ocean, the temperature is usually above 750 °F or 400 °C. The boiling point of a liquid goes up when pressure is put on it (Garrison, 2009). A number of hydrothermal vents have chimneys on top. Precipitating dissolved metals form smokestacks when the heated water comes into contact with the freezing deep ocean water. The hottest vents are the black smokers which spew out iron and sulfide resulting to iron mono-sulfide. Iron mono-sulfide is black and it is also the black smoker. There exist the other smoker which is white, water released in this case is cool and the compounds in it are white, they are calcium, silicon and barium. The following are hydrothermal creatures, squat lobster, tubeworm, Pompeii worm, vent worm and vent crap. These creatures are tolerant to the boiling water around the hydrothermal vents. Particularly the Pompeii worm has a bacteria coated filaments which cover its body. The vent creatures acquire their food from a process referred to as chemosynthesis. The process of chemosynthesis starts with the chemical Hydrogen Sulfide which is released form the hydrothermal vents. The hydrogen sulfide is oxidized by the microbes resulting to nutrients which are fed by animals going up on the food chain (Steele & Thorpes, 2010). Question # 3 Coriolis Effect is a form of an inertial force resulting form the earth’s rotation. The speed of moving objects is not affected by Coriolis Effect. In the southern hemisphere objects are deflected to the left, while in the northern hemisphere objects are deflected to the right by the Coriolis Effect. This particular force works best in long trajectories. Cyclones in the northern hemisphere rotate counterclockwise on the other hand anticyclones in the northern hemisphere rotate clockwise. Weather results from either a higher or a lower pressure. Specifically areas of low pressure are known as cyclones while areas of high pressure are known as anticyclones. In a higher pressure anticyclone air will be pushed outwards and in a lower pressure cyclone air will be pushed inwards. At the northern hemisphere, the air that moves outwards is deflected to the right and thus causing an anti-cyclonic weather which is in a higher pressure rotating clockwise. A deflection which occurs on the air moving inwards at a low pressure results in a cyclonic weather rotating counterclockwise. The above is what makes cyclones in the northern hemisphere rotate counterclockwise while anticyclones have a clockwise movement (Garrison, 2009). Question # 4 When man discovers a new thing whether it is living or non living a lot of debate arises on either to conserve or explore. Environmental conservatives have been on the fore front advocating for conservation, while on the other hand, scientists become interest in conducting research and coming up with new knowledge. In this case after the discovery of hydrothermal vents or also better known as black smokers in 1977, questions are being asked on whether to pursue exploration and research or protection of this ecosystem. I am taking the stance of exploration and research, since this particular ecosystem is very unique and should be studied to form part of the current existing knowledge (Steele & Thorpes, 2010). The ecosystem will be lucrative in terms of minerals like copper, iron, gold and silver which can be mined. The mining of black smokers from the sea can be rather cheaper than mining on normal dry land because it won’t involve digging soil or breaking rocks and it is also a resource which is renewable. Mining of the black smoker is through dragging up chimneys from the ocean bed which are later loaded in barges and taken for processing. When scientist conduct detailed research on how minute creatures survive around the black smokers, this will give knowledge on how human beings can best adapt in the world in the face of global warming. The other important thing with exploration of the hypothermal vent rests in acquiring more knowledge on the geological process and oceanography. The discovery of hypothermal vent came about when scientist was in their exploration missions. Come to think of it, if scientists would have been satisfied with what they had discovered in past decades or century, they would not have come to his point of discovering the hypothermal vent. We can also argue that if scientists are stopped from conducting research and exploration in the name of conservation, human beings will not come to the point of discovering many more interesting things which have not yet been discovered (Steele & Thorpes, 2010). References Garrison T. (2009). Essentials of Oceanography. New York: Brooks/Cole Publishing Co. Steele J, Thorpes S. (2010). Elements of Physical Oceanography: A Derivative of the Encyclopedia of Ocean Sciences. New York: Academic Press. Read More