Lecture PowerPoint Slides
... – Abrupt increase in seismic wave velocity • Transformation of minerals under very high pressures into densely compacted arrangements of atoms, resulting in rock of higher density • Pressures are too high for molten silicate material at depths greater than 660 km ...
... – Abrupt increase in seismic wave velocity • Transformation of minerals under very high pressures into densely compacted arrangements of atoms, resulting in rock of higher density • Pressures are too high for molten silicate material at depths greater than 660 km ...
Presentation
... • an introduction to plate tectonics; • distinction between the ‘facts’ of plate tectonics and the evidence used to support plate tectonic theory; • a survey of some of the evidence supporting plate tectonic theory; • explanation of some of the hazards caused by plate tectonic processes earthquakes ...
... • an introduction to plate tectonics; • distinction between the ‘facts’ of plate tectonics and the evidence used to support plate tectonic theory; • a survey of some of the evidence supporting plate tectonic theory; • explanation of some of the hazards caused by plate tectonic processes earthquakes ...
Chapter 21 - Bemidji State University
... c. The present is the key to the past. 2. Rocks are continuously being fonned, broken down, and refonned as a result of igneous, sedimentary and metamorphic processes. III. Igneous Rocks (80% of Earth's crust) - fonned when molten material from far beneath Earth's surface cools and solidifies. - Ma ...
... c. The present is the key to the past. 2. Rocks are continuously being fonned, broken down, and refonned as a result of igneous, sedimentary and metamorphic processes. III. Igneous Rocks (80% of Earth's crust) - fonned when molten material from far beneath Earth's surface cools and solidifies. - Ma ...
Fig. 15-26, p.370
... An oceanic trench forms at a convergent boundary between two oceanic plates. One plate sinks, generating magma that rises to form a chain of volcanic islands called ...
... An oceanic trench forms at a convergent boundary between two oceanic plates. One plate sinks, generating magma that rises to form a chain of volcanic islands called ...
Introductory Video Script Template
... piece of paper flat on the desk towards the book. What happened? Did it arch up? ...
... piece of paper flat on the desk towards the book. What happened? Did it arch up? ...
EVIDENCE TO THE CONTRARY (CHAPTER 6)
... edge of the continent, that is, near the place where the crust changes from continental to oceanic (See ...
... edge of the continent, that is, near the place where the crust changes from continental to oceanic (See ...
Chapter 10 Resource: Forces Shaping Earth
... Volcanoes can form when plates of Earth’s lithosphere sink into the mantle at subduction zones. These are referred to as subduction volcanoes. The deeper the plates sink, the hotter they become. Eventually the plates begin to melt, becoming magma. Because this newly formed magma is less dense than t ...
... Volcanoes can form when plates of Earth’s lithosphere sink into the mantle at subduction zones. These are referred to as subduction volcanoes. The deeper the plates sink, the hotter they become. Eventually the plates begin to melt, becoming magma. Because this newly formed magma is less dense than t ...
Continental Margins
... We now know that seafloor features result from a combination of tectonic activity and the processes of erosion and deposition. The ocean floor can be divided into two regions: continental margins and deep-ocean basins. The continental margin, the relatively shallow ocean floor nearest the shore, con ...
... We now know that seafloor features result from a combination of tectonic activity and the processes of erosion and deposition. The ocean floor can be divided into two regions: continental margins and deep-ocean basins. The continental margin, the relatively shallow ocean floor nearest the shore, con ...
Convergence of tectonic reconstructions and mantle - HAL-Insu
... linear decrease of the area for increasing age. Young seafloor dominates, but ...
... linear decrease of the area for increasing age. Young seafloor dominates, but ...
The Moho beneath western Tibet: Shear zones and
... At each station we processed the available set of receiver functions using the H-κ analysis method of Zhu and Kanamori (2000). The receiver functions are move-out corrected and stacked for the primary and multiple phases as indicated in Fig. 3 for station ST-07 for a range of plausible H and κ = Vp/ ...
... At each station we processed the available set of receiver functions using the H-κ analysis method of Zhu and Kanamori (2000). The receiver functions are move-out corrected and stacked for the primary and multiple phases as indicated in Fig. 3 for station ST-07 for a range of plausible H and κ = Vp/ ...
The Moho in subduction zones - Earth and Space Sciences at the
... nature of subduction zones implies the convergence of two plates, each characterized by a distinct Moho: one Moho associated with the incoming oceanic plate and another that may be of either continental or oceanic affinity. In this paper, we shall examine the processes operating in subduction zone fo ...
... nature of subduction zones implies the convergence of two plates, each characterized by a distinct Moho: one Moho associated with the incoming oceanic plate and another that may be of either continental or oceanic affinity. In this paper, we shall examine the processes operating in subduction zone fo ...
A) asthenosphere B) stiffer mantle C) inner core D) outer core 1. In
... Base your answers to questions 20 through 22 on the passage and cross section below and on your knowledge of Earth science. The cross section represents one theory of the movement of rock materials in Earth's dynamic interior. Some mantle plumes that are slowly rising from the boundary between Eart ...
... Base your answers to questions 20 through 22 on the passage and cross section below and on your knowledge of Earth science. The cross section represents one theory of the movement of rock materials in Earth's dynamic interior. Some mantle plumes that are slowly rising from the boundary between Eart ...
A) asthenosphere B) stiffer mantle C) inner core D) outer core 1. In
... Base your answers to questions 20 through 22 on the passage and cross section below and on your knowledge of Earth science. The cross section represents one theory of the movement of rock materials in Earth's dynamic interior. Some mantle plumes that are slowly rising from the boundary between Eart ...
... Base your answers to questions 20 through 22 on the passage and cross section below and on your knowledge of Earth science. The cross section represents one theory of the movement of rock materials in Earth's dynamic interior. Some mantle plumes that are slowly rising from the boundary between Eart ...
Slide 1
... Science Questions Primary Questions: From what material did Mercury form, and how? How and when did it become internally differentiated? Is there both primary and secondary crust on Mercury? Secondary Questions: What is the history of crust formation? How does crustal composition vary (i) across the ...
... Science Questions Primary Questions: From what material did Mercury form, and how? How and when did it become internally differentiated? Is there both primary and secondary crust on Mercury? Secondary Questions: What is the history of crust formation? How does crustal composition vary (i) across the ...
Moho comparison
... Five wide-angle profiles on regional gravity map with seven crustal structure domains trending roughly east-west from (1) in the north representing the Venezuela Basin, to (7) in the south representing the South American continent. The domains are not tectonic provinces, although they resemble those ...
... Five wide-angle profiles on regional gravity map with seven crustal structure domains trending roughly east-west from (1) in the north representing the Venezuela Basin, to (7) in the south representing the South American continent. The domains are not tectonic provinces, although they resemble those ...
+ t 1/2
... The apparent future ages of MORB and OIB can be explained by multi-stage fractionations, but the Pb paradox remains. The first Pb Paradox: virtually all mantle reservoirs plot to the right of the Geochron, where are the complimentary reservoirs required for mass balance? ...
... The apparent future ages of MORB and OIB can be explained by multi-stage fractionations, but the Pb paradox remains. The first Pb Paradox: virtually all mantle reservoirs plot to the right of the Geochron, where are the complimentary reservoirs required for mass balance? ...
Eastern Mediterranean geodynamics (PDF Available)
... present-day central movements in this collision zone (Reilinger et al. 1997, 2006). The Anatolian microplate north of these convergent plate boundaries is moving WSW with respect to Eurasia (Figure 1) at ,30 mm/yr along the North (NAF) and East (EAF) Anatolian fault zones (Reilinger et al. 1997). It ...
... present-day central movements in this collision zone (Reilinger et al. 1997, 2006). The Anatolian microplate north of these convergent plate boundaries is moving WSW with respect to Eurasia (Figure 1) at ,30 mm/yr along the North (NAF) and East (EAF) Anatolian fault zones (Reilinger et al. 1997). It ...
PDF (Chapter 2. Comparative Planetology)
... the core. Of the potential core-forming materials, iron, sulfur, oxygen and nickel are by far the most abundant elements. The assumption of a chondritic composition for Mars leads to values of the relative radius and mass of the core: Rc/R = 0.50 and Mc/M = 0.21. The inferred density of the mantle i ...
... the core. Of the potential core-forming materials, iron, sulfur, oxygen and nickel are by far the most abundant elements. The assumption of a chondritic composition for Mars leads to values of the relative radius and mass of the core: Rc/R = 0.50 and Mc/M = 0.21. The inferred density of the mantle i ...
The westward drift of the lithosphere
... the basal décollements affect the entire crust and upper mantle, and the resulting belt has much larger volumes of rocks involved (Doglioni et al., 1999). This could explain why the topography of the east-directed subduction-related orogens is higher than the opposite subduction zones. In fact, when ...
... the basal décollements affect the entire crust and upper mantle, and the resulting belt has much larger volumes of rocks involved (Doglioni et al., 1999). This could explain why the topography of the east-directed subduction-related orogens is higher than the opposite subduction zones. In fact, when ...
Inside the Earth
... By 1929, Alfred Wegener’s ideas were all but dismissed. But, Arthur Holmes elaborated on one of Wegener’s hypotheses: thermal convection and the earth’s mantle. Thermal convection states that, as a substance is heated, its density decreases and it rises. Once it cools, its density increases and it f ...
... By 1929, Alfred Wegener’s ideas were all but dismissed. But, Arthur Holmes elaborated on one of Wegener’s hypotheses: thermal convection and the earth’s mantle. Thermal convection states that, as a substance is heated, its density decreases and it rises. Once it cools, its density increases and it f ...
Sine et al.
... inevitable. We propose the retention of 1 to 2% melt and a temperature increase of 300 to 500°C beneath the GB produces the strong gradient in seismic velocity across the GB-CP boundary. [9] The contrast in seismic velocity across this boundary is not only large but is also very sharp, and our lim ...
... inevitable. We propose the retention of 1 to 2% melt and a temperature increase of 300 to 500°C beneath the GB produces the strong gradient in seismic velocity across the GB-CP boundary. [9] The contrast in seismic velocity across this boundary is not only large but is also very sharp, and our lim ...
Recycling lower continental crust in the North China craton
... that lower crustal foundering occurred within the North China craton during the Late Jurassic, and thus provides constraints on the timing of lithosphere removal beneath the North China craton. Eclogite forms by high- to ultrahigh-pressure metamorphism of basaltic rocks and has a density that is hig ...
... that lower crustal foundering occurred within the North China craton during the Late Jurassic, and thus provides constraints on the timing of lithosphere removal beneath the North China craton. Eclogite forms by high- to ultrahigh-pressure metamorphism of basaltic rocks and has a density that is hig ...
(2013) Porous fluid flow enables oceanic subduction initiation on
... either internal friction coefficient (Figures 3a, 3b, and 3d) or the transform fault width (km; Figure 3c); gray area denotes stagnant lid regime, purple stands for subduction initiation; porosity mentioned is porosity of the upper crust and transform fault. Default model parameters (if not specifie ...
... either internal friction coefficient (Figures 3a, 3b, and 3d) or the transform fault width (km; Figure 3c); gray area denotes stagnant lid regime, purple stands for subduction initiation; porosity mentioned is porosity of the upper crust and transform fault. Default model parameters (if not specifie ...
Plate tectonics
Plate tectonics (from the Late Latin tectonicus, from the Greek: τεκτονικός ""pertaining to building"") is a scientific theory that describes the large-scale motion of Earth's lithosphere. This theoretical model builds on the concept of continental drift which was developed during the first few decades of the 20th century. The geoscientific community accepted the theory after the concepts of seafloor spreading were later developed in the late 1950s and early 1960s.The lithosphere, which is the rigid outermost shell of a planet (on Earth, the crust and upper mantle), is broken up into tectonic plates. On Earth, there are seven or eight major plates (depending on how they are defined) and many minor plates. Where plates meet, their relative motion determines the type of boundary; convergent, divergent, or transform. Earthquakes, volcanic activity, mountain-building, and oceanic trench formation occur along these plate boundaries. The lateral relative movement of the plates typically varies from zero to 100 mm annually.Tectonic plates are composed of oceanic lithosphere and thicker continental lithosphere, each topped by its own kind of crust. Along convergent boundaries, subduction carries plates into the mantle; the material lost is roughly balanced by the formation of new (oceanic) crust along divergent margins by seafloor spreading. In this way, the total surface of the globe remains the same. This prediction of plate tectonics is also referred to as the conveyor belt principle. Earlier theories (that still have some supporters) propose gradual shrinking (contraction) or gradual expansion of the globe.Tectonic plates are able to move because the Earth's lithosphere has greater strength than the underlying asthenosphere. Lateral density variations in the mantle result in convection. Plate movement is thought to be driven by a combination of the motion of the seafloor away from the spreading ridge (due to variations in topography and density of the crust, which result in differences in gravitational forces) and drag, with downward suction, at the subduction zones. Another explanation lies in the different forces generated by the rotation of the globe and the tidal forces of the Sun and Moon. The relative importance of each of these factors and their relationship to each other is unclear, and still the subject of much debate.