Cooling of the Ocean Plates (Lithosphere)
... 3. Continuous plate boundaries 4. Volcanic Island chains - plates moving over fixed mantle plume (melt source) 5. Topography variations consistent with aging plates. ...
... 3. Continuous plate boundaries 4. Volcanic Island chains - plates moving over fixed mantle plume (melt source) 5. Topography variations consistent with aging plates. ...
Plate Tectonics and Layers of the Earth
... magnetic field direction - Rocks show the effects of the reversal – new iron minerals are formed - Magnetometer records magnetic data - Magnetic alignment in the rocks reverses back and forth over time – these match and are parallel with mid-ocean ridges Why is this Important? – it shows new rock wa ...
... magnetic field direction - Rocks show the effects of the reversal – new iron minerals are formed - Magnetometer records magnetic data - Magnetic alignment in the rocks reverses back and forth over time – these match and are parallel with mid-ocean ridges Why is this Important? – it shows new rock wa ...
Chapter 5 Notes: Plate Tectonics Earth’s Interior Direct
... o Magnetic strips The earth’s magnetic poles have reversed many times Evidence in the rocks on the ocean floor o Drilling Samples The samples far from the ridge are older The “youngest” rocks near the center of the ridge ...
... o Magnetic strips The earth’s magnetic poles have reversed many times Evidence in the rocks on the ocean floor o Drilling Samples The samples far from the ridge are older The “youngest” rocks near the center of the ridge ...
nonsequitur - Earth and Atmospheric Sciences
... that plates are perfectly rigid. However real plates do sometimes have internal plate deformation (e.g. Juan de Fuca) • (2) Triple Junctions (TJs) are places where 3 plates meet. Their kinematic and geometric evolution can be predicted from plate tectonics principles as long as the 3 plates maintain ...
... that plates are perfectly rigid. However real plates do sometimes have internal plate deformation (e.g. Juan de Fuca) • (2) Triple Junctions (TJs) are places where 3 plates meet. Their kinematic and geometric evolution can be predicted from plate tectonics principles as long as the 3 plates maintain ...
Crust - Mrs. Bock
... The asthenosphere is the semi-rigid part of the middle mantle that flows like hot asphalt under a heavy ...
... The asthenosphere is the semi-rigid part of the middle mantle that flows like hot asphalt under a heavy ...
Plate Tectonic Theory
... oceanic lithosphere beneath lower density (felsic) continental lithosphere – Formation of magma in the mantle wedge – Formation of a continental margin volcanic arc on the overriding continental lithosphere • Examples: Cascade Range, Andean Range ...
... oceanic lithosphere beneath lower density (felsic) continental lithosphere – Formation of magma in the mantle wedge – Formation of a continental margin volcanic arc on the overriding continental lithosphere • Examples: Cascade Range, Andean Range ...
Lecture 1a Plate Tectonics
... (supercontinent) cycle • J. Tuzo Wilson (“Did the Atlantic close and then re-open?”, Nature, 1966, pp. 676681) suggested that plate tectonics allow supercontinents to rift apart and reform over and over on a roughly half billion year cycle • Evidence for this: evidence of pre-Pangea supercontinents, ...
... (supercontinent) cycle • J. Tuzo Wilson (“Did the Atlantic close and then re-open?”, Nature, 1966, pp. 676681) suggested that plate tectonics allow supercontinents to rift apart and reform over and over on a roughly half billion year cycle • Evidence for this: evidence of pre-Pangea supercontinents, ...
Plate tectonics: What set the Earth`s plates in motion?
... erupted in the middle of immobile plates. Our "The geological record suggests that until three billion years ago the earth's crust was immobile so modelling shows that these early continents could have placed major stress on the surrounding what sparked this unique phenomenon has fascinated geoscien ...
... erupted in the middle of immobile plates. Our "The geological record suggests that until three billion years ago the earth's crust was immobile so modelling shows that these early continents could have placed major stress on the surrounding what sparked this unique phenomenon has fascinated geoscien ...
Section 1: Earth`s Interior (pages 16 – 24)
... from an earthquake. The speed and paths the seismic waves take tell geologists how the planet is put together. Three main layers make up Earth’s interior: (Be able to label layers!) 1. Crust – layer of rock that forms Earths OUTER surface. - It includes both dry land and the ocean floor. - The crust ...
... from an earthquake. The speed and paths the seismic waves take tell geologists how the planet is put together. Three main layers make up Earth’s interior: (Be able to label layers!) 1. Crust – layer of rock that forms Earths OUTER surface. - It includes both dry land and the ocean floor. - The crust ...
Wegener—Continental Drift
... are technological advances that led to the acceptance of this theory and laid the ground work for plate tectonics? • A. Sonar and magnetometers mapped the ocean floor and detected magnetic striping. • B. Satellites created communication networks for scientists on other continents. • C. Computer syst ...
... are technological advances that led to the acceptance of this theory and laid the ground work for plate tectonics? • A. Sonar and magnetometers mapped the ocean floor and detected magnetic striping. • B. Satellites created communication networks for scientists on other continents. • C. Computer syst ...
Lecture 46
... o What materials of appropriate density are available in sufficient abundance to constitute 1/3 the mass of the Earth? o Iron meteorites provide a compositional model of the core. o Again we turn to a chondritic model: we infer that siderophile elements missing from the silicate Earth are in the cor ...
... o What materials of appropriate density are available in sufficient abundance to constitute 1/3 the mass of the Earth? o Iron meteorites provide a compositional model of the core. o Again we turn to a chondritic model: we infer that siderophile elements missing from the silicate Earth are in the cor ...
Th/U - APC
... Distribution in the Earth • U and Th (K?) are thought to be absent from the core and present in the mantle and crust. – Core: Fe-Ni metal alloy – Crust and mantle: silicates ...
... Distribution in the Earth • U and Th (K?) are thought to be absent from the core and present in the mantle and crust. – Core: Fe-Ni metal alloy – Crust and mantle: silicates ...
Inside the Earth
... mass, and collect more particles. • Early Earth generated thermal energy in its interior, making the rocks of the planet soft enough to flow. ...
... mass, and collect more particles. • Early Earth generated thermal energy in its interior, making the rocks of the planet soft enough to flow. ...
A. Layers of the Earth
... The map illustrates the thickness of Earth's crust. Note how the thickest areas (red and dark brown) are beneath some of Earth's important mountain ranges such as: Andes (west side of South America), Rockies (Western North America), Himalayas (north of India in South-central Asia) and Urals (north- ...
... The map illustrates the thickness of Earth's crust. Note how the thickest areas (red and dark brown) are beneath some of Earth's important mountain ranges such as: Andes (west side of South America), Rockies (Western North America), Himalayas (north of India in South-central Asia) and Urals (north- ...
Sea Floor Spreading – 1956-1963
... • World War II and the cold war brought about a great increase in data about the ocean floor – how to interpet? ...
... • World War II and the cold war brought about a great increase in data about the ocean floor – how to interpet? ...
QUIZ
... a. Briefly explain using specific detail or examples how the following observations were used to support Wegener’s hypothesis of continental drift. (choose 3) fit of the continents paleoclimate fossil record glacial evidence mountain ranges and rock types b. What important explanation was missing fr ...
... a. Briefly explain using specific detail or examples how the following observations were used to support Wegener’s hypothesis of continental drift. (choose 3) fit of the continents paleoclimate fossil record glacial evidence mountain ranges and rock types b. What important explanation was missing fr ...
Ch 9 3 Actions at Plate Boundaries
... The system of ridges is the longest physical feature on Earth’s surface (70,000 km long) These features are 1000 to 4000 km wide, not narrow at all Rift Valley – Deep faulted structures found along the ridge system Seafloor Spreading – process by which plate tectonics produces new lithosphere Typica ...
... The system of ridges is the longest physical feature on Earth’s surface (70,000 km long) These features are 1000 to 4000 km wide, not narrow at all Rift Valley – Deep faulted structures found along the ridge system Seafloor Spreading – process by which plate tectonics produces new lithosphere Typica ...
Exercises in basic isostasy
... 3. Assume that continental lithosphere consisting of crust with thickness 36 km, density ρc = 2.8 x 103 kg m-3 is thinned rapidly by horizontal extension to 18 km. Assuming mantle density is ρm = 3.3 x 103 kg m-3, and local isostasy is maintained during and after the extension, what is the new level ...
... 3. Assume that continental lithosphere consisting of crust with thickness 36 km, density ρc = 2.8 x 103 kg m-3 is thinned rapidly by horizontal extension to 18 km. Assuming mantle density is ρm = 3.3 x 103 kg m-3, and local isostasy is maintained during and after the extension, what is the new level ...
Mantle plume
A mantle plume is a mechanism proposed in 1971 to explain volcanic regions of the earth that were not thought to be explicable by the then-new theory of plate tectonics. Some such volcanic regions lie far from tectonic plate boundaries, for example, Hawaii. Others represent unusually large-volume volcanism, whether on plate boundaries, e.g. Iceland, or basalt floods such as the Deccan or Siberian traps.A mantle plume is posited to exist where hot rock nucleates at the core-mantle boundary and rises through the Earth's mantle becoming a diapir in the Earth's crust. The currently active volcanic centers are known as ""hot spots"". In particular, the concept that mantle plumes are fixed relative to one another, and anchored at the core-mantle boundary, was thought to provide a natural explanation for the time-progressive chains of older volcanoes seen extending out from some such hot spots, such as the Hawaiian–Emperor seamount chain.The hypothesis of mantle plumes from depth is not universally accepted as explaining all such volcanism. It has required progressive hypothesis-elaboration leading to variant propositions such as mini-plumes and pulsing plumes. Another hypothesis for unusual volcanic regions is the ""Plate model"". This proposes shallower, passive leakage of magma from the mantle onto the Earth's surface where extension of the lithosphere permits it, attributing most volcanism to plate tectonic processes, with volcanoes far from plate boundaries resulting from intraplate extension.