Characteristics of Mid-Oceanic Ridges
Origins and
Characteristics
of
Mid-Oceanic Ridges
Matthew Olson
ABSRACT
The theory of seafloor spreading emerged with the discoveries of Harry Hammond Hess. Ocean basins are expanding laterally away from a mid-oceanic ridge. Radioactive decay in Earth’s mantle causes convection cycles, which drive plate tectonics. Hot mantle rises and undergoes decompression melt due to change in pressure. New oceanic crust is created in a characteristic sequence. Studies of Ophiolites show a sequence of sediment, pillow basalts, sheeted dikes, and gabbro being formed as hot mantle rises and creates new crust at ridges. The theory of plate tectonics is greatly supported by discoveries made at mid-oceanic ridges.
INTRODUCTION
When one looks across the massive oceans of the world, it is hard to imagine what could exist beneath the vast extent of water covering 70.78% of the planet (Hamblin and Christiansen, 2008). Among the uncharted and most mysterious places of the world, the ocean holds the greatest secrets. However, science has made some incredible discoveries regarding sea-floor characteristics and processes; some of which have impacted the scientific world greatly. Understanding the principles and causes of sea-floor spreading has helped to define one of the most important geological theories of our time; plate tectonics (Wicander and Monroe, 2010). Therefore, through analysis of these ridges, scientists are better able to understand the geological processes occurring in the formation of new oceanic crust; and without the proof that has been gathered regarding mid-oceanic ridges, there would not be evidence sufficient to support the plate tectonic theory. What is responsible for the rifting of these massive mountains beneath the sea, and how is it that mankind came to discover the fascinating origins and characteristics of mid-oceanic ridges?
Plate Tectonics and Earth’s Driving Force
On its return from the pacific at the end of World War II the
Characteristics
of
Mid-Oceanic Ridges
Matthew Olson
ABSRACT
The theory of seafloor spreading emerged with the discoveries of Harry Hammond Hess. Ocean basins are expanding laterally away from a mid-oceanic ridge. Radioactive decay in Earth’s mantle causes convection cycles, which drive plate tectonics. Hot mantle rises and undergoes decompression melt due to change in pressure. New oceanic crust is created in a characteristic sequence. Studies of Ophiolites show a sequence of sediment, pillow basalts, sheeted dikes, and gabbro being formed as hot mantle rises and creates new crust at ridges. The theory of plate tectonics is greatly supported by discoveries made at mid-oceanic ridges.
INTRODUCTION
When one looks across the massive oceans of the world, it is hard to imagine what could exist beneath the vast extent of water covering 70.78% of the planet (Hamblin and Christiansen, 2008). Among the uncharted and most mysterious places of the world, the ocean holds the greatest secrets. However, science has made some incredible discoveries regarding sea-floor characteristics and processes; some of which have impacted the scientific world greatly. Understanding the principles and causes of sea-floor spreading has helped to define one of the most important geological theories of our time; plate tectonics (Wicander and Monroe, 2010). Therefore, through analysis of these ridges, scientists are better able to understand the geological processes occurring in the formation of new oceanic crust; and without the proof that has been gathered regarding mid-oceanic ridges, there would not be evidence sufficient to support the plate tectonic theory. What is responsible for the rifting of these massive mountains beneath the sea, and how is it that mankind came to discover the fascinating origins and characteristics of mid-oceanic ridges?
Plate Tectonics and Earth’s Driving Force
On its return from the pacific at the end of World War II the
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