EARTH AS AN EVOLVING PLANETARY SYSTEM Part 4 ppsx

... oceanic and continental areas (Fig. 4. 18). Some occur on or near ocean ridges, such as Iceland, St. Helena, and Tristan in the Atlantic basin, and others occur near the centers of plates (such as ... the Earth as it accreted, and 4 He, an isotope produced by radioactive decay of U and Th isotopes. Plume-related basalts in oceanic areas have relatively high 3 He/ 4 He ratios,...

Ngày tải lên: 09/08/2014, 11:20

... of asteroids Cooling Breakup of Parent Bodies Fall on the Earth 4. 56 – 4. 53 Ga 4. 54 – 4. 45 Ga 4. 4 – 4. 0 Ga 1000 – 5 Ma 1.5 – 0 Ma Figure 10.15 Summary of the history of meteorites and asteroids. indefinitely ... still occurring on the Earth as ocean-ridge basalts and oceanic plateaus are produced. At least on the Earth and Venus, where substantial heat was available, ea...

Ngày tải lên: 09/08/2014, 11:20

... 350 Contents xiii 1 Earth Systems Earth as a Planetary System A system is an entity composed of diverse but interrelated parts that function as a whole (Kump et al., 1999a). The individual parts, often ... years, the Earth has been considered a complex planetary system that evolved over 4. 6 billion years of time. It includes reservoirs, such as the crust, mantle, and...

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... Pangea. Laurentia, which is also part of Pangea, includes most of North America, Scotland and Ireland north of the Caledonian suture, Greenland, Spitzbergen, and the Chukotsk Peninsula of eastern ... element distri- butions in ocean-ridge basalts and ophiolites. Primitive mantle values from Sun and McDonough (1989), and other data from Bednarz and Schmincke (19 94) and Alabaster et al. (198...

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... Depleted Mantle Lithosphere Lithosphere Mantle SiO 2 46 .0 44 .1 46 .6 43 .6 TiO 2 0.18 0.09 0. 04 0.1 34 Al 2 O 3 4. 06 2.20 1 .46 1.18 FeOT 7. 54 8.19 6. 24 8.22 MgO 37.8 41 .2 44 .1 45 .2 CaO 3.21 2.20 0.79 1.13 Na 2 O ... zones are sutures and which are not. Foreland and Hinterland Basins Peripheral foreland and hinterland basins are like retroarc foreland basins in terms of s...

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... volcanic gases 178 The Atmosphere and Oceans may have caused average ocean salinity to drop significantly during the Triassic and Jurassic. Evaporite deposition has been sharply episodic, and ... Sun was 25 to 30% less luminous than it is today and that its luminosity has increased with time in an approximately linear manner (Kasting, 1987). The paradox associated with this luminosity chang...

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... about 530 Ma, land plants 47 0 Ma, vascular plants 41 0 Ma, amphibians 370 Ma, reptiles and the amniote egg about 330 Ma, insects 310 Ma, mammals 215 Ma, flowering plants 210 Ma, and man about 4 Ma (Australopithecus ... that many nonvolatile elements such as U, Th, and rare earth elements (REEs), which are Earth s Primitive Crust 267 Major Archean Cratons Stanovoy Aldan Omolon Ladoga...

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... Whereas most of Africa, Antarctica, Australia, and the Americas formed in the Archean and Paleoproterozoic, much of Eurasia formed in the Meso- and Neoproterozoic and the Phanerozoic. Secular Changes ... separate terranes with unique stratigraphy and deformational histories (Van Kranendonk et al., 2002): an eastern terrane (3.72–2.85 Ga), a western terrane (3.27–2.92 Ga), and the Kuranna te...

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... plume volcanism. Except for the Siberian and Emeishan Traps in eastern Asia, all major flood basalt provinces in the last 200 My are associated with the opening a new ocean basin (Coffin and Eldholm, ... 24 0.11 3398 3. 94 3.75 2.5 0.8 Jupiter 5.2 11.9y 13 318 71,600 1.32 Saturn 9.2 29.5y 9.7 95.2 60,000 0.69 Uranus 19.1 84y 6.8 14. 5 25,600 1.27 Neptune 30 164y 5 .4 17.2 24, 760 1. 64 Pl...

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... appearance of, 239– 240 events 1.9 Ga, 336– 345 2.7 Ga, 345 – 346 causes of mantle-plume, 347 –350 mantle-plume, 315, 329–331, 331– 347 evolution, comparative planetary, 355, 40 2 40 5 evolution, crustal and ... T., and Basu, A. R., 1995. Synchrony and causal relations between Permian–Triassic boundary crises and Siberian volcanism. Science, 269: 141 3– 141 6. Reymer, A., and Schubert,...

Ngày tải lên: 09/08/2014, 11:20