State three pieces of evidence for the existence of crustal plates.?
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One piece of evidence is the symmetry of ocean floor spreading.\n\nAnother is the way some of the continents seem to fit together like a jigsaw puzzle (the east coast of South America and the west coast of Africa, for example). \n\nYou could argue that the pattern of the Hawaiian volcanoes is evidence that the Pacific plate has travelled in a northeastenly direction over the hot spot now feeding the active volcanoes of Mauna Loa, Kilauea, and Loihi (underwater). The farther you move away from the hot spot in the southeast corner of the Hawaiian islands, the older and smaller the islands get, until you get to Kure Atoll and the seamounts beyond.
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The tectonic plates are "floating" on a liqid mantle that has convection currents.  These convection move the plates around the globe.  This is the science behing plate tectonics
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Introduction\nPlate tectonics is a relatively new theory that has revolutionized the way geologists think about the Earth. According to the theory, the surface of the Earth is broken into large plates. The size and position of these plates change over time. The edges of these plates, where they move against each other, are sites of intense geologic activity, such as earthquakes, volcanoes, and mountain building. Plate tectonics is a combination of two earlier ideas, continental drift and sea-floor spreading. Continental drift is the movement of continents over the Earth's surface and in their change in position relative to each other. Sea-floor spreading is the creation of new oceanic crust at mid-ocean ridges and movement of the crust away from the mid-ocean ridges.
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Brouse around this site - it is excellent.\n\nhttp://www.palaeos.com/Earth/Geography/Pangea.htm
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1) phototropism, I'm down with that...\n\nHow 'bout these? 2) evolution, 3) plate tectonics. That's got us up to 3. Still looking for two more.
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These are all related to the crusts. \n\nA divergent boundary occurs when two Earth tectonic plates move away from each other, causing a depression or a range. \n\nSubduction occurs underwater when seawater tectonic plates converge into continental plates. Since seawater tectonic plates are more dense than continental plates, it 'subduct's and goes under. \n\nThere's more than 3 types of magma, depending on its temperature, density, and composition.\n\nAs you know, the plate tectonics theory says that the Earth's crust is moving constantly. By applying the observations of divergent boundaries through time (ex, Great Rift Valley created over centuries), that will -support- and -clarify- the plate tectonics theory. So, divergent boundaries being observed serves as evidence and support for the theory.\n\nSubduction occurs in sea-floor spreading, which explains why crusts closer to the mid-atlantic ridge are "warmer" and "younger", while the ones further away, and most likely closer to a subduction zone is colder. This shows that the Earth's crust is once again moving, once again indicating that the theory is true. \n\nMagma is formed when divergent boundaries move away from each other, and is replaced by new crusts formed by magma. The cycle of sea-floor spreading undergoing subduction, sinking under the continental crust, melting into magma, then re-forming  at the Mid-Atlantic ridge.
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Some are moving away from each other (i.e. their separation is increasing), such as Africa and South America. Some are moving closer together, like North America and Asia. Some places continents or pieces of continents are moving past each other, like in the Pacific Northwest, or in the Afar Triangle in Somalia. Some places are expanding, like Iceland. \n\nThere are lots of ways to measure this, but the first clue that something was going on came from looking at the shapes of coastlines. Look at the coastlines of western Africa and eastern South America. They look like they could fit together, like a puzzle. The rocks match each other on both continents too, as if the two continents were once fit together. \n\nHowever, the big clue that something was going on came from magnetic stripes on the sea floor. As new basalt forms in the middle of the Atlantic, and some other oceans, it pushes out from the central mid-ocean ridge, and cools. When it cools, it sets, taking on a magnetization aligned with the magnetic field of the earth at that moment. However, the earth's magnetic field flips every few thousand years (just like the Sun's does, every 11.5 years or so). This creates a record of magnetic stripes on the sea floor that alternate polarity. When the scientists Vine and Mathews saw this, they knew they had proved that plate tectonics existed, and that the continents were moving (sometimes away from each other, and sometimes towards each other or past each other)
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No i would respond by questioning the molecular construction of a trilobite and whether it could be dated to a pre jurassic age or whether it was just another anomaly from the mariners trench in the pacific
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You can find an abstract of an article written on this subject at the url below. The title and volume listed below. \n\nIn a nutshell, the dates on this huge mafic-ultramafic complex in Brazil (old ocean floor possibly) point to two big events in the earth's early tectonic history: First, a Mesoproterozoic extension event (like a spreading ridge) that forms the mafic-ultramafic complex (ocean crust and seafloor)(1583±25 Ma , 1565±22 Ma-million years ago).  Then, a continental collision event: younger dates of 770–795 Ma (million years ago) for  metamorphism of the complex (" high-grade amphibolite to granulite facies prograde metamorphism"), may represent the timing of a continental collision event.   \n\nZircon and rutile U---Pb geochronology of the Niquelândia layered mafic and ultramafic intrusion, Brazil: constraints for the timing of magmatism and high grade metamorphism\n\nby Ferreira-Filho and several others.\nPrecambrian Research \nVolume 68, Issues 3-4 , August 1994, Pages 241-255
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The Earth's rocky outer crust solidified billions of years ago, soon after the Earth formed. This crust is not a solid shell; it is broken up into huge, thick plates that drift atop the soft, underlying mantle. \nThe plates are made of rock and drift all over the globe; they move both horizontally (sideways) and vertically (up and down). Over long periods of time, the plates also change in size as their margins are added to, crushed together, or pushed back into the Earth's mantle. These plates are from 50 to 250 miles (80 to 400 km) thick. \nThe map of the Earth is always changing; not only are the underlying plates moving, but the plates change in size. Also, the sea level changes over time (as the temperature on Earth varies and the poles melt or freeze to varied extents), covering or exposing different amounts of crust. \nThe current continental and oceanic plates include: the Eurasian plate, Australian-Indian plate, Philippine plate, Pacific plate, Juan de Fuca plate, Nazca plate, Cocos plate, North American plate, Caribbean plate, South American plate, African plate, Arabian plate, the Antarctic plate, and the Scotia plate.
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Try http://www.geo.lsa.umich.edu/~crlb/COURSES/270/Lec12/Lec12.html\nIt helped me do my homework! Also, it has pictures of plate boundries and plate tectonics. Hope it helps!
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If there was a worldwide flood, there should be layers of rock that could be determined to be pre-flood, a layer laid down during the flood, and layers that are post-flood. With all the "Creation Scientists" looking for some type of evidence to support their notions that there was a global flood, not one has found anything remotely close to the sequence I stated.
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1. aa\n2. fissure\n3. vulcan\n4. tectonic\n5. pacific (also called the "pacific rim")
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One. It was called pangaea heres some more info:\n\nPangaea or Pangea (derived from Παγγαία, Greek for "all earth") is the name given to the supercontinent that existed during the Paleozoic and Mesozoic eras, before the process of plate tectonics separated each of the component continents into their current configuration. The name was coined by Alfred Wegener, chief proponent of Continental Drift in 1915.\n\nThe continents apparently first coalesced to form Pangaea about 300 Mya (million years ago), giving rise to several prominent mountain ranges by the process known as orogeny. Several of these ranges still exist, although they have become much lower by means of erosion. The Appalachians of eastern North America, the Atlas Mountains of North Africa, and the Urals of Eurasia are prime examples. The mantle under Pangaea's former location seemingly remained very hot even after coalescence, convection currents within the underlying magma pushing the centre of the supercontinent upward. As a result, the area that is now the continent of Africa was situated tens of meters higher than the surrounding continents.\n\nIn configuration, Pangaea was a C-shaped landmass that spread across the equator. The body of water that was enclosed within the resulting crescent has been named the Tethys Sea. Owing to Pangaea's massive size, the inland regions appear to have been very dry due to the lack of precipitation. The large supercontinent would potentially have allowed terrestrial animals to migrate freely all the way from the South Pole to the North Pole.\n\nThe vast ocean that once surrounded the supercontinent of Pangaea has been named Panthalassa. Pangaea, it seems, broke up about 180 Ma in the Jurassic Period, firstly into two supercontinents (Gondwana to the south and Laurasia to the north), thereafter into the continents as we understand them today.\n\nPangaea was not the first supercontinent. From the evidence available, scientists reconstruct that a predecessor, termed Pannotia, formed about 600 Ma, before dividing again some 50 million years later. Another, Rodinia, apparently formed approximately 1,100 Ma and divided 750 Ma.
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I got an idea\n\nHow about one magma chamber passing another on its way to the surface. The one magma chamber says to the other "Are you on your way to the top?". The other magma chamber replies "Yeah, I don't mean to intrude".\n\nI got another one. One continent is approaching another continent on a tectonic plate. The one continent says "you're very subductive" and the other continent says, "I don't know, I think we should just have a plutonic relationship"\n\nIt's funny?\n\nOne more. Two magma chambers are sittin' havin' a chat. One magma chamber says to the other "did you see that young intrusive that came up the other day, boy was she hot!". The other magma chamber says "Don't get your hopes up, she's a dyke."\n\nHave I gone too far? No?\n\nOkay I have one last one. I promise\n\nTwo sulphide crystals are floatin' around in a magma chamber. One of them says to the other "look at the cleavage on that sweet little feldpar over there." The other suphide crystal says "pff, silicon."\n\nThank you everyone and g'night.
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1. earth's tilt\n2. earth rotation\n3. earth revolution
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I like this site for looking at where the continents were at different times as the forces of plate tectonics (continental drift) occured.\nhttp://www.scotese.com/earth.htm\n\n50MYA: http://www.scotese.com/newpage9.htm\n150MYA: http://www.scotese.com/late1.htm\n\nThey even project into the 250MY into the future:\nhttp://www.scotese.com/future2.htm\n\nThey also animate the movement of the plates:\nhttp://www.scotese.com/newpage13.htm