does the crust move around more easily than the rock in the lower mantle?
98234
The crust is way lighter than the rock of the lower mantle, and its volume is tiny in comparison. So if by "easily" you mean how much energy is required to move the rock, then the crust moves around much easier than the rock in the lower mantle.
317463
When liquid magma comes out of the earths crust at the mid-oceanic ridge, it cools rapidly forming crystals. These crystals have magnetic properties that align the crystal according to the earths magnetic field at the time they cooled, similar to how a compass needle points north, the magnetism in the crystal indicates which direction was north when the crystal was formed.\n\nHowever, the direction that is north today, was not always north in the past, in fact many times in geologic history, the north and south poles were reversed entirely. This is reflected in the "magnetic bands" found in rock on the ocean floor.\n\nSo, if you imagine the Atlantic Ocean between the U.S. and Europe, there is a mid-ocean ridge between the two. If the plates never moved, then the magma coming out of this ridge would just pile up, but instead, this is the "engine" that moves the plates away from one another. As you move from the mid-ocean ridge towards the continents, the crystals in the rock have different magnetic orientations that show these flip-flops of the earths magnetic field through geologic history. Because this material originated at the mid ocean ridge, but is now closer to the continents, it shows that the earths crust, the floor of the ocean, is moving AWAY from the mid-ocean ridge and TOWARDS the continents.\n\nThere are a lot of  diagrams that would probably help you understand this better. CHeck out a geology book, or look online.\nGood Luck!
475416
Nope; the oceanic plates are spreading apart, as new material (magma) is pushed up from below.  They are not crashing together at all.
557773
Are you serious? ;) Well, I'll try to be:\n\n1. Continents are made up mostly of intrusive or plutonic granitic rocks, oceanic crust of extrusive or volcanic basaltic rocks. Example: compare some Himalayan rock with a hardened lava fragment from Mauna Loa in Hawaii.\n\n2. Continental rocks are lighter and of greater volume - they therefore protrude above the oceanic crust, if you dig very deep down they also have deeper roots. The oceanic crust is denser but thinner.\n\n3. Continental rocks are in general much older. This doesn't mean that oceanic rocks didn't exist before, but they get swallowed up (well, buried real deep and remelted, etc.) in trenches, the deepest parts of the oceans.
98681
No we don't have the ability now, not only is the temperature too great, there is way too much pressure for us to overcome. It would crush anything significant before we got to far. \n\nThe farthest down that we have been is only a few thousand km, and that with a tiny drill.\n\nThe deepest holes in the crust are natural. Volcanoes bring up material from tens of km depth. The crust thickness averages about 18 miles (30 kilometers) under the continents, but is only about 3 miles (5 kilometers) under the oceans. It is light and brittle and can break. \n\nHere is a great article that explains a lot:\nhttp://www.livescience.com/technology/050407_earth_drill.html\n\nThe reason we explore space more, is because not only is it easier to accomplish, but it is also far safer and less costly. I agree though that exploring below the Earth can be quite rewarding, but we simply can't do it as of now.
628638
Depends on who you read.  Ranges are from 700-1300C or 820-1020C.\n\nOne site says, \n"temperature between 1300 and 700 degrees C"\nhttp://www.cobweb.net/~bug2/rock7.htm\n\nWhile another says,\n"We show that the mantle in this region is at a minimum temperature of 820 C and a maximum temperature of 1020 C; the latter is some 200 C colder than that suggested in a recent interpretation of an observed collocated low velocity zone from a teleseismic survey"\nhttp://www.dias.ie/~ajones/papers/100.pdf
1177187
The lithosphere (from the Greek for "rocky" sphere) is the solid outermost shell of a rocky planet. On the Earth, the lithosphere includes the crust and the uppermost layer of the mantle (the upper mantle or lower lithosphere) which is joined to the crust.\n\nAs the cooling surface layer of the Earth's convection system, the lithosphere thickens over time. It is fragmented into relatively strong pieces, called tectonic plates (shown in the picture), which move independently relative to one another. This movement of lithospheric plates is described as plate tectonics.\n\nThe distinguishing characteristic of the lithosphere is not composition, but its flow properties. Under the influence of the low-intensity, long-term stresses that drive plate tectonic motions, the lithosphere responds essentially as a rigid shell and thus deforms primarily through brittle failure, whereas the asthenosphere (the layer of the mantle below the lithosphere) is heat-softened and accommodates strain through plastic deformation. Both the crust and upper mantle float on the more plastic asthenosphere. The crust is distinguished from the upper mantle by the change in chemical composition that takes place at the Moho discontinuity.\n\nThere are two types of lithosphere:\n\noceanic lithosphere \ncontinental lithosphere \nOceanic lithosphere is about 70 km thick (but can be as thin as 1.6 km at the mid-ocean ridges), while continental lithosphere is about 150 km thick (and can be considerably thicker at continental collision zones). Oceanic lithosphere consists mainly of mafic and ultramafic rocks and is denser than continental lithosphere, which consists predominantly of felsic rocks. This higher density has the effect that at subduction zones the oceanic plate will invariably sink underneath the continental plate. New oceanic lithosphere is constantly being produced at mid-ocean ridges from mantle material and is recycled back to the mantle at subduction zones. As a result, oceanic lithosphere is much younger than continental lithosphere: the oldest oceanic lithosphere is about 200 million years old, while parts of the continental lithosphere are billions of years old. As oceanic lithosphere grows older, it gets cooler and denser, with the result that if two oceanic plates converge, the older one will subduct below the younger one.\n\nhttp://en.wikipedia.org/wiki/Lithosphere\n\nBoys mature slower than girls so they seem stupid. \n\nGood Luck!
228826
It's because as the slab descends, it stays fairly cold (because rock doesn't conduct heat very well!), and the pressure increases.  As the pressure increases, certain minerals change their shape to more compact arrangments, typically losing water and other "volatiles" (this is called slab dehydration).  When these volatiles are lost, they move upwards into the overlying "mantle wedge", where they lower the melting point of the rock.  It's from here that magmas arise.  The reason for the 100km or so distance from the zone of subduction is due to the slab "dehydration" not occuring until a certain depth, and because the slab typically descends at an angle of ~60deg
373975
The Earth is not a perfect sphere so you are at different distances from the centre at different places.\nThe density of the Earth is not constant so above dense rocks you appear slightly heavier.\nThe Earth spins so at the equator you are lifted slightly by the Eotovos effect.
855026
Most earthquakes happen along the edge of the oceanic and continental plates. [Oceanic plates are under water, continental plates are above.] The earth's crust (the outer layer of the planet) is made up of a bunch of pieces, called plates. The plates get moved around by the liquid layers of magma underneath the Earth's crust. The plates are always bumping into each other, and pulling away from each other or past eachother. Earthquakes usually happen when two plates are running into each other or sliding past each other. They can also happen along faults, too though.
16395
This process is known as plate tectonics. The earth's surface is composed of large 'plates' which gradually move around over time. The movement is driven by convective currents of molten rock within the asthenosphere. Movement begins at the midocean ridges, which are actually larger than continental mountain ranges. As magma builds these ridges the weight of the material, combined with the convective flow causes them to push outward towards the outer parts of the oceanic plates. Some of these plates subduct (go under) the continental plates, or even other oceanic plates. This subduction process lifts continents higher and leads to mountain building. You can see some illustrations here:\nhttp://www.ucmp.berkeley.edu/geology/tecmech.html\nYou can watch animated versions showing the plate motion here:\nhttp://www.ucmp.berkeley.edu/geology/tecmech.html\n\nAs for parts of the earth falling into the ocean, that is just a not-so-serious thing that people say trying to explain plate tectonics. There are zones of continental crust that are rifting, being split apart, and these may eventually move below sea level. Some examples of this are the Great Rift Basin in northern Africa. The Red Sea is a rift zone that has submerged, and the Dead Sea is part of a rift zone. \n\nThese processes are quite slow on our time scale. The Pacific Ocean is spreading about 4-5 cm per year.\n\nAnd if you've ever heard that California is going to fall into the ocean- don't worry it isn't. The boundary between the Pacific Plate and the North American plate is actually within California, but the motion is such that Los Angeles is moving north towards San Francisco. Millions of years from now, Los Angeles may be moved north of San Francisco.
751689
The crust and mantle are generally solid.  The inner and outer core are molten rock and metal...very dense, but still liquid.
1099478
Tectonic plates are moving.
728536
If you are asking what is below the surface of the oceanic basins (lithosphere), it is the mantle (asthenosphere) consisting of a combination of magma a pliable plastic rock.  Further down is the inner core of liquid magma.  Beyond that it has been traditionally  "conjectured" by geologist to be a solid iron core.  However, recent developments from fringe science (outside the mainstream of conventional science), supported by Russian geological hypotheses, questions this, and counter-postulates a thermal nuclear core.
114510
Like pauliegone said, the lithosphere does in a way seperate the crust from the mantle.  The tectonis plates (crust) are supported by this semisolid layer.  However, the lithosphere is considered, by some scientists, part of the mantle.  So, it depends on which scientists you believe, although I believe that pauliegone is correct.
580759
Basaltic oceanic crust is more dense.\n\n^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n\nCONTINENTAL CRUST\n# Less Dense (lighter weight): average density = 2.7 gm per cubic centimeter\n# Thicker: 0 to 40 km, average 35 km under high mountains, the crust can be thickened, up to 65 km. Under the craton, the average thickness is 30 km.\n# Mineral Composition: granitic (felsic) rocks such as granodiorite and granite enriched in Potassium (K), Sodium (Na), Aluminum (Al), and Silica (Si)\n# "Floats" on top of the Mantle\n\nOCEANIC CRUST\n# More Dense (heavier): average density = 3.0 gm per cubic centimeter\n# Thinner: 0 to 10 km, average 5 km, thinnest at Mid-Ocean Ridges\n# Mineral Composition: mafic rocks such as basalt and gabbro enriched in Magnesium (Mg) and Iron (Fe)\n# Underlies Ocean Basins.
724538
Oceanic crust is fundamentaly different from Continental because of its origin.  Oceanic crust is formed as the continents move apart and new 'material' is forced between the plates.  You may have seen the video of lava being extruded at the bottom of the ocean 'toothpaste style'.  This forms round lumps of 'pillow lava' which have no crystals (because it cooled very quickly the crystals don't have time to form).  Below this you'll see the same material (chemically) but which forms columns of basalt (like Giant's causeway in Ireland) as it cooled slower.  Below this is the layered basalts which will form a much more massive block of basalt.  Below this is peridotite.\nChemically speaking oceanic material is basaltic whereas continental is granitic.\nContinental volcanic rocks are a lot less systematic in structure as they just intrude through thick layers of other material although they'll generally have larger crystals and will be lighter in colour.  \nBecause of their increased silica content they're more explosive and so this will be seen by the steeper sides of the volcanoes, pumice (solidified ash), etc.