Presnall, D. C. (1980) A double partial melt zone in the mantle beneath mid-ocean ridges, Phys. Earth Planet. Int., 23, 103-111.
... 1978; Walker eta!., 1978) and Anderson and Minster (1980) have pointed out that the thickness of the lithosphere depends on whether seismic, thermal, or rheological properties are being considered. It will be seen in the following discussion that if the model of Presnall et a!. (1979) for the genera ...
... 1978; Walker eta!., 1978) and Anderson and Minster (1980) have pointed out that the thickness of the lithosphere depends on whether seismic, thermal, or rheological properties are being considered. It will be seen in the following discussion that if the model of Presnall et a!. (1979) for the genera ...
Chapter 23 Test Review Notes
... Compare the type of information obtained with a precision depth recorder with that obtained by a gravity corer. A precision depth recorder produces a continuous record of seafloor depth under the ship as it moves over an area. A gravity corer provides information about the seafloor at one point only ...
... Compare the type of information obtained with a precision depth recorder with that obtained by a gravity corer. A precision depth recorder produces a continuous record of seafloor depth under the ship as it moves over an area. A gravity corer provides information about the seafloor at one point only ...
Technological Advance and Seafloor Mapping Mid
... flowing liquid iron and nickel in the outer core. This magnetic field causes iron to align itself like the needle of a compass aligns to point north. Periodically, the north and south poles switch because the flow of the iron and nickel switches. This is called a magnetic reversal. During a ma ...
... flowing liquid iron and nickel in the outer core. This magnetic field causes iron to align itself like the needle of a compass aligns to point north. Periodically, the north and south poles switch because the flow of the iron and nickel switches. This is called a magnetic reversal. During a ma ...
Geological maps
... • Mid-ocean ridge = the high range of mountains that runs under the oceans and is the site of “spreading” • Seamount chain = line of undersea peaks that extends from a “hot spot” in the mantle (only one end of the chain can be volcanically active and there is no associated “trench”) ...
... • Mid-ocean ridge = the high range of mountains that runs under the oceans and is the site of “spreading” • Seamount chain = line of undersea peaks that extends from a “hot spot” in the mantle (only one end of the chain can be volcanically active and there is no associated “trench”) ...
Earth Science Vocabulary Chapter 9: Plate Tectonics Section 9.1
... Divergent Boundary- a region where the rigid plates are moving apart, typified by the oceanic ridges Convergent Boundary- a boundary in which two plates move together Transform Fault Boundary- a boundary in which two plates slide past eachother without creating or destroying lithosphere Section 9.3: ...
... Divergent Boundary- a region where the rigid plates are moving apart, typified by the oceanic ridges Convergent Boundary- a boundary in which two plates move together Transform Fault Boundary- a boundary in which two plates slide past eachother without creating or destroying lithosphere Section 9.3: ...
Plate Boundaries
... formation of new lithosphere Plates move away from a ridge margin New molten material wells up from the mantle Molten material cools-new crust is formed Continuous process ...
... formation of new lithosphere Plates move away from a ridge margin New molten material wells up from the mantle Molten material cools-new crust is formed Continuous process ...
The Earth How the crust moves…
... • Most are located on ocean floor, a few on land – Friction spawns earthquakes along slipstrike faults ...
... • Most are located on ocean floor, a few on land – Friction spawns earthquakes along slipstrike faults ...
Marine Biology Worksheet I
... the density to increase. 3. When sea ice forms salt is left behind causing the density to increase 4. The cold salty dense surface water sinks bringing oxygen to the ocean depths. 5. The surface water has oxygen due to two things: • There is enough light at the surface for photosynthesis. Oxygen is ...
... the density to increase. 3. When sea ice forms salt is left behind causing the density to increase 4. The cold salty dense surface water sinks bringing oxygen to the ocean depths. 5. The surface water has oxygen due to two things: • There is enough light at the surface for photosynthesis. Oxygen is ...
Plate Tectonics U2L4 Cloze Name: ______ 1. The supercontinent
... 1. The supercontinent called ________ formed 300 million years ago and began to break up 200 million years ago. 2. The process by which new oceanic lithosphere sea floor forms when magma rises to Earth’s surface, called ________ _________, occurs at mid-ocean ridges and solidifies, as older existing ...
... 1. The supercontinent called ________ formed 300 million years ago and began to break up 200 million years ago. 2. The process by which new oceanic lithosphere sea floor forms when magma rises to Earth’s surface, called ________ _________, occurs at mid-ocean ridges and solidifies, as older existing ...
Plate Tectonics Review Worksheet
... Plate Tectonics Review Worksheet 1. Continental Drift: A theory proposed by Alfred Wegner that said all continents were once joined 300 million years ago in a single land mass called Pangaea. Over time the continents moved to their present day locations. 2. What are four pieces of evidence for conti ...
... Plate Tectonics Review Worksheet 1. Continental Drift: A theory proposed by Alfred Wegner that said all continents were once joined 300 million years ago in a single land mass called Pangaea. Over time the continents moved to their present day locations. 2. What are four pieces of evidence for conti ...
earth
... • The theory of continental drift states that the continents were once a single landmass that drifted apart and are still doing so. ...
... • The theory of continental drift states that the continents were once a single landmass that drifted apart and are still doing so. ...
handout (with color figures)
... Ocean circulation is forced by the exchange of heat, freshwater and momentum with the atmosphere. Distribution of sea surface temperature (SST) reflects the pattern of net heat flux (solar – terrestrial – sensible heat – latent heat) at the ocean surface. SST varies between 30 oC to –1.6oC. Similarl ...
... Ocean circulation is forced by the exchange of heat, freshwater and momentum with the atmosphere. Distribution of sea surface temperature (SST) reflects the pattern of net heat flux (solar – terrestrial – sensible heat – latent heat) at the ocean surface. SST varies between 30 oC to –1.6oC. Similarl ...
15.4 Marine Ecosystems
... 15.4 Marine Ecosystems The ocean can be divided into zones. • Ocean zones can be determined by their distance from shoreline and water depths. – intertidal zone—between low and high tide – neritic zone—from intertidal zone neritic zone intertidal zone to continental shelf bathmat zone – bathyal zon ...
... 15.4 Marine Ecosystems The ocean can be divided into zones. • Ocean zones can be determined by their distance from shoreline and water depths. – intertidal zone—between low and high tide – neritic zone—from intertidal zone neritic zone intertidal zone to continental shelf bathmat zone – bathyal zon ...
Plate Tectonic Vocabulary
... -Boundary along which two tectonic plates move toward each other -Characterized by subduction or continental collision -Crust is usually destroyed ...
... -Boundary along which two tectonic plates move toward each other -Characterized by subduction or continental collision -Crust is usually destroyed ...
SEA FLOOR SPREADING Mid
... • At deep-ocean trenches, subduction allows part of the ocean floor to sink back into mantle, over tens of millions of years. • Subduction and Earth’s Oceans • Earth’s ocean floor is renewed about every 200 million years. ...
... • At deep-ocean trenches, subduction allows part of the ocean floor to sink back into mantle, over tens of millions of years. • Subduction and Earth’s Oceans • Earth’s ocean floor is renewed about every 200 million years. ...
Words to know
... Mid ocean ridge—the fracture zone along the ocean bottom where molten mantle material comes to the surface, thus creating new crust. This fracture can be seen beneath the ocean as a line of ridges that form as molten rock reaches the ocean bottom and solidifies. ...
... Mid ocean ridge—the fracture zone along the ocean bottom where molten mantle material comes to the surface, thus creating new crust. This fracture can be seen beneath the ocean as a line of ridges that form as molten rock reaches the ocean bottom and solidifies. ...
Notes
... The oceanic crust moves about ________________ centimeters per year. The melting crust will become a _______________________________ Oceanic to Oceanic form a ______________________________ zone. When 2 oceanic crusts collide they form an ocean _____________________. Ocean trenches are extremely__ ...
... The oceanic crust moves about ________________ centimeters per year. The melting crust will become a _______________________________ Oceanic to Oceanic form a ______________________________ zone. When 2 oceanic crusts collide they form an ocean _____________________. Ocean trenches are extremely__ ...
Chapter 3 - Perry Local Schools
... puzzle – One supercontinent - Pangaea – Laurasia and Gondwanaland ...
... puzzle – One supercontinent - Pangaea – Laurasia and Gondwanaland ...
The Theory of Plate Tectonics - Ouray School District R-1
... produce large mountains (hymliays) 3) Oceanic vs oceanic: One goes under the other and the subducted plate produces magma that forms and rises to form an island arc. ...
... produce large mountains (hymliays) 3) Oceanic vs oceanic: One goes under the other and the subducted plate produces magma that forms and rises to form an island arc. ...
Abyssal plain
An abyssal plain is an underwater plain on the deep ocean floor, usually found at depths between 3000 and 6000 m. Lying generally between the foot of a continental rise and a mid-ocean ridge, abyssal plains cover more than 50% of the Earth’s surface. They are among the flattest, smoothest and least explored regions on Earth. Abyssal plains are key geologic elements of oceanic basins (the other elements being an elevated mid-ocean ridge and flanking abyssal hills). In addition to these elements, active oceanic basins (those that are associated with a moving plate tectonic boundary) also typically include an oceanic trench and a subduction zone.Abyssal plains were not recognized as distinct physiographic features of the sea floor until the late 1940s and, until very recently, none had been studied on a systematic basis. They are poorly preserved in the sedimentary record, because they tend to be consumed by the subduction process. The creation of the abyssal plain is the end result of spreading of the seafloor (plate tectonics) and melting of the lower oceanic crust. Magma rises from above the asthenosphere (a layer of the upper mantle) and as this basaltic material reaches the surface at mid-ocean ridges it forms new oceanic crust. This is constantly pulled sideways by spreading of the seafloor. Abyssal plains result from the blanketing of an originally uneven surface of oceanic crust by fine-grained sediments, mainly clay and silt. Much of this sediment is deposited by turbidity currents that have been channelled from the continental margins along submarine canyons down into deeper water. The remainder of the sediment is composed chiefly of pelagic sediments. Metallic nodules are common in some areas of the plains, with varying concentrations of metals, including manganese, iron, nickel, cobalt, and copper. These nodules may provide a significant resource for future mining ventures.Owing in part to their vast size, abyssal plains are currently believed to be a major reservoir of biodiversity. The abyss also exerts significant influence upon ocean carbon cycling, dissolution of calcium carbonate, and atmospheric CO2 concentrations over timescales of 100–1000 years. The structure and function of abyssal ecosystems are strongly influenced by the rate of flux of food to the seafloor and the composition of the material that settles. Factors such as climate change, fishing practices, and ocean fertilization are expected to have a substantial effect on patterns of primary production in the euphotic zone. This will undoubtedly impact the flux of organic material to the abyss in a similar manner and thus have a profound effect on the structure, function and diversity of abyssal ecosystems.