Plate Boundaries - Westfield School
... At a divergent plate boundary, two plates move apart. As the two plates move apart, magma rises up to fill the gap. This causes volcanoes. However, since the magma can escape easily at the surface the volcano does not erupt with much force. Earthquakes are also found at divergent boundaries. An exam ...
... At a divergent plate boundary, two plates move apart. As the two plates move apart, magma rises up to fill the gap. This causes volcanoes. However, since the magma can escape easily at the surface the volcano does not erupt with much force. Earthquakes are also found at divergent boundaries. An exam ...
fun with food! plate tectonics and our national parks
... To simulate a divergent plate boundary, push down on the two broken cookie halves and slide them apart. Notice that the creamy filling between the two broken “plates” may tend to flow upward, similar to the rising, decompression, and partial melting of hot asthenosphere at mid-ocean ridges and conti ...
... To simulate a divergent plate boundary, push down on the two broken cookie halves and slide them apart. Notice that the creamy filling between the two broken “plates” may tend to flow upward, similar to the rising, decompression, and partial melting of hot asthenosphere at mid-ocean ridges and conti ...
Evidence Statements: HS-ESS2-1
... Develop a model to illustrate how Earth’s internal and surface processes operate at different spatial and temporal scales to form continental and ocean-floor features. [Clarification Statement: Emphasis is on how the appearance of land features (such as mountains, valleys, and plateaus) and sea-floo ...
... Develop a model to illustrate how Earth’s internal and surface processes operate at different spatial and temporal scales to form continental and ocean-floor features. [Clarification Statement: Emphasis is on how the appearance of land features (such as mountains, valleys, and plateaus) and sea-floo ...
volcanic
... soft, and gives easily • Rock at the edges of tectonic plates is under great stress. • The boundaries between tectonic plates have been seismically active for millions of years • The last place that motion in an earthquake is detected. ...
... soft, and gives easily • Rock at the edges of tectonic plates is under great stress. • The boundaries between tectonic plates have been seismically active for millions of years • The last place that motion in an earthquake is detected. ...
Ocean Crust - The University of Southern Mississippi
... and crust. The Moho may coincide with the top of the transition zone of layered gabbros and peridotites. 3. Source of magnetism in the crust - integrated over all of the crust, but a. The pillow basalts are most strongly magnetized, but thin b. The rest of the crust is weakly magnetized, but holds a ...
... and crust. The Moho may coincide with the top of the transition zone of layered gabbros and peridotites. 3. Source of magnetism in the crust - integrated over all of the crust, but a. The pillow basalts are most strongly magnetized, but thin b. The rest of the crust is weakly magnetized, but holds a ...
Teleseismic surface wave tomography in the western US using the
... The non-granitic Cascade Range is characterized by nearly average wave speeds. Modest low velocities are observed throughout the Basin and Range province, probably due to elevated crustal temperatures resulting from relatively thin lithosphere (22). The northern Columbia Plateau and the western Snak ...
... The non-granitic Cascade Range is characterized by nearly average wave speeds. Modest low velocities are observed throughout the Basin and Range province, probably due to elevated crustal temperatures resulting from relatively thin lithosphere (22). The northern Columbia Plateau and the western Snak ...
Thermal Convection Experiments
... Convection in the Earth: Thermal convection is inferred to exist on a large scale in at least two regions in the Earth. The liquid outer core and the upper mantle that behaves as a solid for seismic wave propagation and as a very viscous fluid for long duration geologic processes including convecti ...
... Convection in the Earth: Thermal convection is inferred to exist on a large scale in at least two regions in the Earth. The liquid outer core and the upper mantle that behaves as a solid for seismic wave propagation and as a very viscous fluid for long duration geologic processes including convecti ...
Recent tectonic plate decelerations driven by mantle convection
... Figure 3. Present-day tectonic plate accelerations in the global NNR reference frame. (a) Predicted, convection-driven plate accelerations and rate of change of horizontal divergence rate. The horizontal divergence rate is an angular measure of the rate of spreading and convergence of plates at ridg ...
... Figure 3. Present-day tectonic plate accelerations in the global NNR reference frame. (a) Predicted, convection-driven plate accelerations and rate of change of horizontal divergence rate. The horizontal divergence rate is an angular measure of the rate of spreading and convergence of plates at ridg ...
Volcanism in the Afar Rift sustained by decompression melting with
... Continental breakup is caused by some combination of heating and stretching1,2 . The Afar Rift system in Africa is an example of active continental rifting, where a mantle plume probably weakened the lithosphere through thermal erosion and magma infiltration. However, the location and degree of plum ...
... Continental breakup is caused by some combination of heating and stretching1,2 . The Afar Rift system in Africa is an example of active continental rifting, where a mantle plume probably weakened the lithosphere through thermal erosion and magma infiltration. However, the location and degree of plum ...
IgPetMORB13
... the heavy rare earths (HREE). This has been interpreted as a residual garnet effect. The effect is small, however, and MORB have relatively high and unfractionated HREE in comparison to all OIB basalts. MORB have 230Th/238U activity ratios greater than 1, implying that residual garnet may be holding ...
... the heavy rare earths (HREE). This has been interpreted as a residual garnet effect. The effect is small, however, and MORB have relatively high and unfractionated HREE in comparison to all OIB basalts. MORB have 230Th/238U activity ratios greater than 1, implying that residual garnet may be holding ...
Evidence for melting of garnet pyroxenite in the generation of
... garnet pyroxenite in the origin of the garnet signature in MORB [e.g. Hirschmann and Stolper, 1996]. At high degrees of mantle melting, such as that responsible for the generation of MORB, the signature of pyroxenitic melting may be difficult to detect unambiguously. However, because pyroxenites hav ...
... garnet pyroxenite in the origin of the garnet signature in MORB [e.g. Hirschmann and Stolper, 1996]. At high degrees of mantle melting, such as that responsible for the generation of MORB, the signature of pyroxenitic melting may be difficult to detect unambiguously. However, because pyroxenites hav ...
this PDF in a full window.
... Serpentinization reactions, the transformation of a dry peridodite to a wet serpentinite, have received considerable attention in the passive margin community (e.g. (Skelton et al., 2005)). One reason is that non-volcanic rifted margins show wide ocean-continent transitions zones of serpentinized ma ...
... Serpentinization reactions, the transformation of a dry peridodite to a wet serpentinite, have received considerable attention in the passive margin community (e.g. (Skelton et al., 2005)). One reason is that non-volcanic rifted margins show wide ocean-continent transitions zones of serpentinized ma ...
Spring 2001
... continental shelves are seen in red above the deep ocean basin. Down the center of the basin the ocean floor shallows due to the buoyancy of hot new plate freshly formed along the MidAtlantic Ridge. The existence of Iceland is due to a huge swell in the ocean floor causing it to rise above sea level ...
... continental shelves are seen in red above the deep ocean basin. Down the center of the basin the ocean floor shallows due to the buoyancy of hot new plate freshly formed along the MidAtlantic Ridge. The existence of Iceland is due to a huge swell in the ocean floor causing it to rise above sea level ...
The Paleozoic/Mesozoic tectonic evolution of Eastern Australia
... variety of datasets, consistently showing close spatial relationships between Australia and continents such as North America and South China. In this project promising candidate continental pairs are to be studied in conjunction with geophysical and aged geochemical datasets assembled in the vicinit ...
... variety of datasets, consistently showing close spatial relationships between Australia and continents such as North America and South China. In this project promising candidate continental pairs are to be studied in conjunction with geophysical and aged geochemical datasets assembled in the vicinit ...
Earths Layer Model
... Students will learn about the earth’s layers and make a model. They will explore the layers of earth through an interactive board where they can test their knowledge. Then they will do an activity where they make a 3D model of the earth’s layers with a half of a foam ball. Students will color code e ...
... Students will learn about the earth’s layers and make a model. They will explore the layers of earth through an interactive board where they can test their knowledge. Then they will do an activity where they make a 3D model of the earth’s layers with a half of a foam ball. Students will color code e ...
Document
... • The waves are also refracted. • In particular this is called the Mohorovicic discontinuity or Moho. • Several other discontinuities exist within the Earth (but we are only expected to know the Moho) ...
... • The waves are also refracted. • In particular this is called the Mohorovicic discontinuity or Moho. • Several other discontinuities exist within the Earth (but we are only expected to know the Moho) ...
Mantle flow beneath Arabia offset from the opening Red Sea
... contains some of the oldest crust in the Arabian Shield, of Paleoproterozoic age, but present to the west [Stoeser and Frost, 2006]. Similarly, the locus of rifting may have been controlled by preexisting weakness in the continental lithosphere [Dixon et al., 1989; Cloetingh et al., 1995]. [15] This ...
... contains some of the oldest crust in the Arabian Shield, of Paleoproterozoic age, but present to the west [Stoeser and Frost, 2006]. Similarly, the locus of rifting may have been controlled by preexisting weakness in the continental lithosphere [Dixon et al., 1989; Cloetingh et al., 1995]. [15] This ...
Jeopardy Sem. 1 Review
... The type of collision that occurs when two lithospheric plates converge is determined primarily by this characteristic of plates ...
... The type of collision that occurs when two lithospheric plates converge is determined primarily by this characteristic of plates ...
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.