can someone give me a paragraph about how canyons are formed?
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<A canyon, or gorge, is a valley walled by cliffs. Most canyons originate by a process of long-time erosion from a plateau level, with a stream gradually carving out its valley. The cliffs form because harder rock strata that are resistant to erosion and weathering remain exposed on the valley walls. Canyons are much more common in arid areas than in wetter areas because weathering has a lesser effect in arid zones. Canyons' walls are often formed of resistant sandstones or granite. Submarine canyons are those which form underwater, generally at the mouths of rivers.
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ok. i am giving u links which will help u find the right information fast and efficiently. since you have to write in ur words, its better that u deduce the answers urself. it should be quite simple and it will help you.\n\nbasically granite is an igneous rock which is formed due to the cooling down and crystallization of molten magma. here are the links which will help u. there is a file included which is quite informative.\n\nMost of the sites have overlapping information, so use the info u need. Have fun and do cite the links as the sources
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The valley is formed from rifting, so a streching of the crust creates an opening.  This also creates high mountains around the valley.  These mountain erode and this sand, gravel and mud is deposited into the new valley.  THey are transported mainly via streams and rivers, which all combine to form the Rio Grande River itself.
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If you mean how did they form...\n\nOpals form from hydrothermal solutions containing silicon dioxide. That simply means heated water containing dissolved quartz.\n\nThese solutions are deposited in sedimentary rocks where they come out of solution. Sedimentary rock is where you find opals.\n\nOpals contain small amounts of water in its structure. That is what gives it its "play of colors".\n\nIt is often referred to as hydrated silica & is called cryptocrystalline quartz because it is essentially quartz without a crystal structure.\n\nSome of the world's most beautiful opals come from Australia & Mexico. The ones found in Mexico often have a reddish "play of colors" & is called fire opal.
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well I don't know how old it is but I'm pretty sure they formed from two tectonics plates crashing in a convergent matter causing reverse faults\n\nin other words two land plate crashed and all that pressure made the mountains
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An unconformity is a break or a gap in the geologic record. It represents a break in time in the depositional process and can include a period of significant erosion.\n\nThe primary processes that create unconformities in sedimentary rock are eustacy and tectonics. That is sea level change and movement of the earth’s plates. As sea level falls it can expose deposits such as carbonate platforms which will begin to erode and form a karst surface. As sea level rises over this cave and karst system, it will be buried and become what is known as paleokarst. In clastic depositional systems sea level fall will cause rivers to cut downward into their own deposits and delta systems, creating what is called an incised valley. As sea level rises again these incised valleys will be filled again by the same rivers. The base of the new deposits represents the unconformity. \n\nPlate tectonics can also be responsible for lifting areas above sea level. In fact, the two processes of eustacy (sea level) and tectonics are very difficult to separate by examining the rock record. As plates rise, rivers will cut incised valleys, and carbonate platforms will be exposed. Likewise, as plate tectonics cause plates to sink the same systems will be affected and deposition will resume over the new unconformity. \n\nIn aeolian systems climate changes can cause unconformities. As a climate changes from a dry desert to a wetter type of environment, plants can take hold and bring an end to aeolian system. Eventually this may develop into a soil surface and be drowned by sea level changes, beginning a new episode of deposition over the unconformity. All paleosols (ancient soils) represent an unconformity.  \n\nIn volcanic terranes the unconformities are created by the gaps in time between eruption events. These can be short, or millions of years long. \n\nIn a metamorphic terrane an unconformity often is found between eroded metamorphics and sedimentary rocks.
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That has absolutely no sense at all...\n\nHow do you think the Rocky Mountains and the Andes were formed but by millions of years of earthquakes????\n\nWas it hot then?\n\nOf course not! Some of them occured during the glacial era. No SUVs then!\n\nStop listening to stupid people such as Greenpiss!!!
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click here:http://en.wikipedia.org/wiki/U-shaped_valley
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As the Earth buckled, deep cracks penetrated to the buried sandstone layer.\n\nErosion (wind and rain) wore away exposed rock layers and enlarged the surface cracks, isolating narrow sandstone walls, or fins. \n\nAlternating frosts and thawing caused crumbling and flaking of the porous sandstone and eventually cut through some of the fins.\n\nThe resulting holes were enlarged to arch proportions by rockfalls and weathering (again the effects of wind and rain).
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They are meanders.   They can develop into oxbow lakes if, for example, the meander is like a C so that the ends of the C are close together.   Then, if there is a flood, the water may join the ends together, forming a D shape (can't turn the D round!), the water rushes down the straight edge, depositing silt where the C shape meets the straight edge.   Then you end up with an oxbow lake.   \n\nThen I thought I would find a little bit of information for you about meanders that would not confuse you as much as my oxbow explanation!\n\nA meander is a bend in a river, also known as an oxbow loop. A stream or river flowing through a wide valley or flat plain will tend to form a meandering stream course as it alternatively erodes and deposits sediments along its course. The result is a snaking pattern as the stream meanders back and forth across its floodplain. When a meander gets cut off from the main stream body, an oxbow lake is formed.\n\nA meander is formed because the river flows faster on the outside edge of any small curve and slower along the inside edge. Deposition of sediment occurs on the inner edge because the river, moving slowly, cannot carry its sediment load, creating a slip-off slope. The faster moving current on the outside bend has more erosive ability and the meander tends to grow in the direction of the outside bend, forming a river cliff. This can be seen in areas where willows grow on the banks of rivers; on the inside of meanders, willows are often far from the bank, whilst on the outside of the bend, the roots of the willows are often exposed and undercut, eventually leading the trees to fall into the river. This demonstrates the river's movement.\n\nOrigin of term\nThe term derives from the Maeander River river in Turkey, characterised by a very convoluted path. As such, early usage of the term, from the late 1500s, referred to convoluted and windy speech and ideas, as well as the geomorphological feature. The river in Turkey is called Menderes River, south of Izmir, near the town of ancient Greek town of Miletos.\n\nMeander ratio\nMeander ratio is a means of quantifying how much a river or stream meanders (how much its course deviates from the shortest possible path). It is calculated as the length of the stream divided by the length of the valley. A perfectly straight river would have a meander ratio of 1 (it would be the same length as its valley), while the higher this ratio is above 1, the more the river meanders.
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The best way to observe this will be from abutments in layers, one layer within the soil zone will be directly on top of and/or cut off layers below.\n\nThe induvidual features each have their own special features.  Debris flows are matrix-supported with large chuncks on top toward the middle of the deposit.  slumps will have extensional features at the top (cracks), and compressional features at the base (folds).  They are also associated with springs along the plane of weakness.  Slides will be normally graded (big on bottom, small on top).\n\nLahars are completely different, and have volcanic origins.
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Orogeny is the building of mountains.  Most mountains are formed when one techtonic plate subducts under another pushing the top plate up.  Mount Everests includes sedimentary rock that was part of the sea.  The subduction can sweep seawater and silt under a plate setting up the conditions for huge volcanoes as magma is formed and rises through the stratta above as in the Andes.
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the simplest explanation is as follows:\n\n* igneous rocks are formed when molten lava is erupted on to the earth's surface and cools. i.e. basalt lavas. \n\n* sedimentary rocks are formed when other rocks (possibly igneous, metamorphic or previous sediemtnary rocks) are eroded chemically or physically and are then redeposited. i.e. sandstones and mud stones.\n\n* metamorphic rocks are formed when other rocks (igneous or sedimentary typically) are buried and then exposed to high temperatures and pressures that change the properties of that rock. i.e. marble - metamorphosed limestone.
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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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OMGGG!! I can go on forever on this one... but I'll try to be as brief as possible. \n\nOk, so rocks are made by three different processes: \n\n- Volcanic eruptions - These rocks are called IGNEOUS ROCKS.  There are various types of rocks that can be produced.  They can be from either when lava flows on the surface of the earth and cools down, or when magma inside a volcano cools down before it hits the surface.  It doesn't take all that long for these types of rocks to form, and hese rocks are usually crystallized and can be easily distinguished because of the crystal type of formation.\n\n- Another tyoe of rocks - called SEDIMENTARY ROCKS are a result of erosion by wind, water, or glaciers.  These types of rocks may take thousands or even millions of years to form.  So, in this process, sediment (the tiny particles) that is eroded away from the different erosion processes settle in one place and over a long period of time they are formed into rocks. One layeer after the next. \n\n- And the last types of rocks are formed from either Igneous rocks or Sedimentary rocks.  These are called METAMORPHIC ROCKS... word derived because thise rocks have "morphed" into something that is no longer sedimentary or igneous rocks.  These rocks go through these changes and become Metamorphic due to the high pressure which causes heat to build up in these solids.  These rocks can also be relatively easily distinguished because when you look at them, you can actually see flat grains.\n\nso, no! Rocks do not magically appear but they appear over time.  \n\nThere is tons more to the subject, as in you can actually study a given rock and tell how old it actually is and when it was originally formed, but that's another question! :)\n\nhope this helped... \nCheers!
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Two ideas: 1. Eroded (continental glaciers form deep valleys)\n                 2. Depressed (see link on isostacy)\n\nMaybe look in your text book.
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Erosion forms sand\nSand settles as sediment\nSediment hardens over time\nVoila, Sandstone