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Topography of the Ocean Floor Parts of an ocean wave • The winds cause waves on the surface of the ocean (and on lakes). The wind transfers some of its energy to the water, through friction between the air molecules and the water molecules. Stronger winds (like storm surges) cause larger waves. Guyots and Sea Mounts • A guyot /giɘʊ/, also known as a tablemount, is a flat-topped _________. • Guyots are most commonly found in the ________________ • Location and formation • There are thought to be an estimated 50,000 seamounts in the Pacific basin. The _________ ____________ are an excellent example of an entire volcanic chain undergoing this process. • __________ show evidence of having been above the surface with gradual subsidence, the sinking down of land resulting from natural shifts. Their flatness is due to erosion by waves, winds, and atmospheric processes. Mid Ocean Ridge • A ________________ or mid-oceanic ridge is an underwater __________ range, typically having a valley known as a _____running along its spine, formed by ________________ • The mid-ocean ridges of the world are connected and form a single global mid-oceanic ridge system that is part of every ocean, making the midoceanic ridge system the ____________ __________________ in the world. The continuous mountain range is 65,000 km (40,400 mi) long and the total length of the system is 80,000 km (49,700 mi)[ Sea floor Spreading • The uplifted sea floor results from ___________ currents which rise in the mantle as _______ at a linear weakness in the _________ _________, and emerge as ______, creating new crust upon cooling. Continental Shelf • Due to the __________ available in shallow waters, the continental shelves teem with life Continental Shelf Food Web The global continental shelf, highlighted in cyan Continental Shelf • The continental shelf is the extended perimeter of each ___________and associated ________ _______, and was part of the continent during the glacial periods, but is undersea during interglacial periods such as the current epoch by relatively shallow seas (known as shelf seas) and gulfs. • The largest shelf – the __________ ________ in the Arctic Ocean – stretches to 1500 kilometers (930 miles) in width. • Some continents do not have a continental shelf, but rather directly to the slope. • The ___________ __________ connects the continental shelf and the oceanic crust. Life in the Continental Slope • As the continental slope plunges into the deeper parts of the ocean, conditions quickly change. The water becomes much ________ and more sluggish. It is also devoid of life, and _________levels decline as well. As a result, the ocean life along the continental slope is markedly different than that found along the continental shelf, as it must be much more tolerant of __________ conditions. The deeper these animals live, the more intense the ___________ gets; organisms from shallower depths, including humans, would literally start to implode from the pressure Frilled Shark • Fang tooth fish • FREAKY CRITTERS from the deep • Frilled Shark • Fang tooth fish Abyssal Plain Abyssal Plain • Abyssal plains are ________or very gently sloping areas of the _________ ocean basin floor. They are among the Earth's flattest and smoothest regions and the __________ __________. Deep Sea Trench • Trenches define one of the most important natural boundaries on the Earth’s solid surface, that between two ______________ plates. • There are three types of lithospheric plate boundaries: divergent (where lithosphere and oceanic crust is created at mid-ocean ridges), convergent (where one lithospheric plate sinks beneath another and returns to the mantle), and transform (where two lithospheric plates slide past each other). Length North to South: 11,000 miles Deepest point: Mariana Trench at 35,797 feet Meaning of 'Pacific': 'Peaceful' Average Depth: 14,000 feet Islands in the Pacific: About 25,000 Temperature: 32 °F to 84 °F