How long does it take for sandstone to form?
86931
It depends on the type of cement and some other circumstances.\n\nEogenesis (early diagenesis) in sand can create sandstone in as little as a few years, or tens of years in the right environment. Sandstone may be cemented by quartz, calcite, clay minerals, gypsum, anhydrite, iron oxides, and other things. In an evaporitic environment sulphates like gypsum or anhydrite could cement sand into sandstone quite rapidly. Calcite is another cement that could precipitate by rapid evaporation.  One example of an environment where sandstone might form quite rapidly in this manner is an alluvial fan that is close to an evaporitic lake, like in Death Valley. I would suggest that similar environments exist near the Dead Sea.  \n\nHowever, most sandstone is cemented by quartz and clay minerals, and these often take high pressure and temperature to be deposited (diagenesis).  To reach higher pressures it may take many thousands of years, or even millions of years for the unconsolidated sandstone to be buried and eventually cemented. \n\nSource: Notes from Dr. Earl McBride's sedimentology classes.
680163
Tablets...generally about an hour\nLiquid Gels...about 30-45 minutes
461210
Anywhere from 2 to 5 days.
865740
2-4 days... max 5  do me a favor and think of me beating the hell out of a watermelon when ur hittin that next rock ... good luck :(
693931
While they can be equal in hardness one would normally find that the granite, being of igneous origins, is more chemically bonded and therefore more difficult to break apart.  However, the individual minerals within the granite may be harder or softer than the sandstone which is usually composed of quartz which has a hardness of 7.  If the sandstone is porous, it will not take extreme cold well at all as any moisture inside the pores will freeze and thereby facture the rock.The granite doesn't have this problem.
77398
With water, 2 or 3 months.\n\nWithout water, 3 days.
560722
If it's your first baby, it may take as long as 6 months, but it can also take as little as 3 months. It depends on a few things, how tall you are, how long your torso is, if it's your first baby, how much you are eating, how much amniotic fluid is being produced. At first, all you will notice is bloating, then you will start to notice a little bulge. No one else will notice for a while. It really depends on the person.
84859
There are three ways actually:\n1. Rainwater soaks into the ground. Almost all soil will allow water to soak in and as it goes downward it encounters rock which also has small holes called pores that water can soak into. This is how water gets into wells that we drink from or use for irrigation. \n\nThe other two types do not always fit the definition of 'groundwater' but are found beneath the earth's surface:\n\n2. When rocks like sandstone are formed, they are mostly formed (deposited) beneath the ocean or under a river delta. They are filled with water when they form and this water is often trapped there by sediments like clay that deposit over the water filled sandstone. This water is often saltwater. \n\n3. When some rocks deep in the earth undergo a process called metamorphism they chemically expel water. Many rocks have water bound up as part of their chemical content and when this rock changes from pressure or heat the water is released. Some types of clay will also release water that is bound up chemically in the clay when they are buried and under higher temperature and pressure.
719643
This depends on the mineral being formed. For instance, silicate based minerals (from igneous rocks) are fromed by the cooling effect of molten lava. The size of the mineral formed is dependant on the length of time the 'lava' has to cool. This process is called crystalisation. \nIn sedimentary rocks, minerals are formed by erosion, chemical changes, de-salination (extraction of water, although the mineral was present in the water to start with i.e halite), pressure and temperature.
1056060
Caves form in limestone rock. I believe you are asking about the process. So here it goes...\n\nAs water moves through the ground it becomes slightly acidic due to the decomposition of organic material. The acid formed is a mild carbonic acid.\n\nAs this mildly acidic water reaches the rock it permeates the cracks and crevices. Over time, the acid reacts w/ the limestone (calcium carbonate - CaCO3) & dissolves it.\n\nThe cracks get larger. Over long periods of time these cracks can get extremely large resulting in a cave.\n\nIf a cave gets large enough it will be considered a cavern.\n\nSometimes a cavern will collapse due to the weight of the overlying material. When this happens a sinkhole occurs.\n\nSinkholes can be small or large depending upon the size of the cavern beneath & the area of structural weakness.\n\nSometimes a cavern collapses b/c groundwater is pumped out for local supplies. When this happens, there is no support left holding up the roof of the cavern & it gives way.\n\nFlorida is notorious for the number of sinkholes that occurs there. Of course, Florida has limestone bedrock underlying the entire state so this is bound to happen on a regular basis. Also, Florida's population is growing & so is their need for water.\n\nKarst topography is the term given to areas that are dominated by limestone landforms that were created from dissolution by acidic groundwater.
173138
These are examples of cements that make sedimentary rocks:\n\nIn sandstone:\n1. quartz (probably most common)\n2. carbonate (calcite, siderite, ferroan dolomite, etc)\n3. analcime\n4. chlorite\n5. anhydrite/gypsum\n6. halite\n7. illite/kaolinite (generally are replacement minerals but can act as cement)\n8. feldspar (authigenic)\n9. hematite\n\nThere are probably dozens more. Any mineral that is soluble in water can precipitate out and form a cement. Most commonly this will be quartz or some type of carbonate, but most of the above I mentioned are fairly frequent. \n\nIn limestone and dolomite the cements are generally calcite/dolomite, but fractures often exhibit zonation with siderite and ferroan dolomite filling the fractures as later cements. Rarely, carbonate hydroxyapatite (dahllite) cements phosphate bearing limestones.\n\nI'm a petrographer.
1145084
I don't especially like any of your choices, and I am a petroleum geologist. I will address them one at a time to explain. \n\nOil can slowly migrate: Yes, oil does migrate through *POROUS* rock such as limestone and sandstone. The process generally takes thousands of years, if not millions of years, so migration would not explain any new oil discoveries in historic times. Even porous rock is not 'empty' and the migrating oil will have to displace water before it can move.  \n\nOil is made quickly: FALSE. Oil is made from organic matter that is buried in sedimentary rock, and when it is buried deep enough to reach temperatures above 140 degrees F (60 C) it will undergo a chemical change called catagenesis, forming oil. At higher temperatures natural gas is formed. The youngest oil known to have been found was about 4,000 years old. Most oil is much older, often ten to twenty million years older and may have spent millions of years undergoing catagenesis. \n\nThe areas have shale: Shale is a common source rock for oil. Shales are a very common type of rock that contain several percent of organic material. Shale may be the rock where oil is formed, but it is not the rock where oil is stored and recovered from. Shale is generally has no porosity, so as shale undergoes catagenesis, it expels the oil. It does not store significant quantities of oil. There are shale source rocks that are generating oil today, and some oil reservoirs may be being supplied by these source rocks, but it is not likely that they generate oil as fast as it can be pumped, so the oil being currently generated is a very minor source at best. There have been decades of research trying to get oil from 'oil shales' with few promising results. The current research into oil shale is focused on actually cooking the shale to create oil from the organic material in the shale. \n\nAs for the comment about abiogenic oil: It may be possible, but no known reservoirs of abiogenic oil have ever been discovered. The major proponent of abiogenic oil predicted it would be found in rocks other than sedimentary rock (igneous rocks), and it has not been discovered to date, so would be considered both rare and unlikely.\n\nA much better answer to your question that was not offered as a choice:\nOil is sometimes found in abundace in areas where some years ago there didn't seem to be enough there to justify drilling, because some years ago the technology and geological knowledge was not sufficient to detect what was already there. One of the biggest natural gas fields in Canada was drilled through repeatedly before anyone noticed it. That field was passed over by all the major oil companies who did not recognize the natural gas in their exploration wells because they did not expect it to be there in a water-saturated rock. \n\nHere are some sources:\nHunt,John M., 1996, Petroleum Geochemistry and Geology, New York: W.H. Freeman and Company, 743 pp\n\nHere is a simplified set of illustrations and text that explain oil formation and the process of migration and trap:\nhttp://www.priweb.org/ed/pgws/systems/systems_home.html\nYoung oil:\nhttp://www.science-frontiers.com/sf076/sf076g09.htm
56915
Generally, they're formed by freezing and erosion. Essentially what happens is that water gets into the cracks of larger rocks and then freezes and expands, causing pieces to fall off. Sometimes these smaller rocks end up in streams or rivers where they are carried by the current and rolled along the bottom, smoothing them out. over time, they get smaller and smoother becoming what we know as pebbles.
242420
Wow, amazingly my roommate's 10 year old did this experiment for his science project a few weeks ago.  If the still water is hot, it doesn't take too long.  I think it was around 30 seconds for the mix to be complete.  If the water is cold, then it takes significantly longer (if you mean complete diffusion, then it would probably take five minutes).  We stopped the timer when we could not see a significant amount of clear water, and it appeared that the dye had spread through most of the water.  I think it was around 3 minutes (maybe a little more).  We used a cup of water and two drops of dye for each test.  We timed hot water and cold water spreading.
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To understand sedimentary rock layers, it is important to understand that the earth's surface is always slowly - but constantly - changing.  Mountains and other areas that are raised above the surrounding land are subject to wind, rain, and water which constantly wear them down.  The bits of sand, pebbles, and rubble that get worn down from mountains, mesas, and cliffs are pulled by gravity to the low-lying areas (valleys, lake beds, sea-shores) where they collect over time.  Over millions of years, these deposits can harden and petrify into sedimentary rock layers.  Other sedimentary rock layers (like limestone) form on ancient sea or lake beds and are the remains of the various animals and plants that lived in the water.\n\nThus when you look at the different layers of the Grand Canyon, you are looking at the petrified remains of what was once the surface of the earth (or the bottom of a sea bed) at a time the region was being covered with sedimentary material.  Different rock layers occur when changes to the environment cause one type of material to stop being deposited and new materials get deposited instead.  For example, a shallow sea may create layers of limestone.  If the sea later dries up and the now exposed sea bed gets covered over with blowing dry sand, then a layer of sandstone will be deposited on top of the limestone.  In this way, geologists can see how the surface of the earth changes at a given spot over time.\n\nAs for the specific rock layers in the Grand Canyon, here is a VERY SIMPLISTIC description of the situation and processes that produced the major rock layers (from the oldest layer at the bottom to newest at the top):\n\nVishnu Schist (bottom) - 1.7+ billion years ago the area around Grand Canyon was a series of volcanic islands surrounded by a shallow sea.  The resulting deposits of ash, sand, and mud created shales, sandstones and mudestones that were eventually compressed and distorted with time and pressure into gneiss and schist.\n\nTapeats Sandstone - There is a long period where the rocks from this area did not survive and so no record is left (the Great Unconformity).  Eventually this area became part of the edge of the still forming North American continent.  Sandy beaches in this area around 540 million years ago created this sandstone formation.\n\nBright Angel Shale - The water moved further inland, causing this area to be frequently underwater and covered with deposits of mud (which is where shale comes from).\n\nMuav Limestone - The water got deeper and the area became part of the sea-floor proper leading to limestone deposits.\n\nFollowing the Muav Limestone, the sea appears to have receded and the land was again above water.  Little is left from this period.\n\nRedwall Limestone - Around 363 million years ago, the sea moves in rapidly again and the area is once again part of a sea floor leading to limestone deposits.\n\nSupai Group and Hermit Shale - This is actually a lot of smaller layers (a mix of shales, mudstones, and limestones) created as the sea came in and went out numerous times over a period of 30 million years.\n\nCoconino Sandstone - The seas pulled back and this part of North America became part of a vast sand-dune filled desert (similar to North Africa).  The Coconino Sandstone is the petrified remains of ancient sand dunes.\n\nToroweap Formation and Kaibab Limestone (top of canyon) - The sea came back and turned the area first into shallow mud flats (Toroweap) and then drowned it completely into a sea floor (Kaibab) about 240 million years ago.\n\nOne frequent related question... how can Grand Canyon rock layers be from the bottom of a sea when the canyon rim is at 6000+ feet elevation, did the water get that high?  The answer is no... at the time that the sea floor deposits were created, this part of North America was much lower (ie: below sea level).  \n\nThe reason you can find limestone rock layers with fossil fish and clams at high elevations above current se
796671
Hey, \n\nWell, u need ALOT of time for rock synthesis and the best u can do at that is crystal synthesis using salt or best sugar supersaturated solution with a thick rope/string suspended from the top of the glass that is about 3/4 full of supersaturated solution.\n\nWell, u can't grow a plant nor grow a crystal in 3 days.   But u CAN do a project demonstrating the relationship between kinetic energy and potential energy.  It is always not that long to do.  \n\nIf it's for a school board science fair, GOOD LUCK.  These things take so much time and planning out.   Better luck next year getting started earlier with a moderately feasible project that can be done within a reasonable time frame (alot earlier than due date) so that u can anayze and write on the results. \nU can always take a theory in science and test the validity of that theory by conducting an experiment of your imagination.  For example, a simple gravity experiment... then supplement that with mathematical equations as proof... and voila! it looks sophisticated.  \n\nSorry, I can't help u much at this point.  U will just have to find yourself a science project book or science text book in physics (best for quick ones) and conduct that "experiment" (experiments don't need to grow anything. You can measure or use scientific analysis/method for physics projects).  You can get points for creativity by adding or giving a twist to the project in the text. Make sure you cite it.
115109
The process is known as catagenesis. Here is how it works: (By the way, oil can range in age from millions of years to only a few thousand years old- and some biogenic natural gas is being generated almost as it is pumped from the ground)\n\nCrude oil and natural gas is formed from accumulations of small organisms, mostly phytoplankton and zooplanton that are buried in sediments in both marine and lacustrine (fresh water) environments. Other organic material is mixed in such as spores, pollen, woody material, and other material such as fecal pellets from marine organisms. These materials often settle through the water into an organic-rich mud that is very low in oxygen (anaerobic) so there are few organisms to feed on the material and it accumulates over long periods of time. Rivers contribute to this process by both delivering large quantities of organic matter, and also large amounts of sediment to bury this organic matter.\n\nOver time these clay-rich sediments are buried under thousands of feet of sediments, dewatered by pressure from the overlying sediment and become shale. As the shale is buried its temperature increases due to geothermal warming. When it reaches temperatures and pressures of 140 degrees F. (60 C) it begins to convert to oil. As temperature increases from continuing burial processes it reachs a temperature where it begins to form natural gas. Both the oil and the gas are gradually expelled from the shale. Typically shales are found in depositional settings where they may be interbedded with sandstones. Sandstones will have higher porosity (more and bigger holes) than shale and the oil and gas will displace salt water that is remaining in the sandstones. Eventually the oil and gas migrates upward through the water and if the overlying structure has formed some sort of a trapping configuration, (like a sandstone overlain by an impervious shale, or a fault that has created a seal against the sandstone, then this becomes an oil reservoir.\n\nA very similar process occurs in carbonate rocks, like limestone and dolomite, except the organic material originates within the carbonate rock in many instances. If the carbonate reef (for example) has been buried by an impervious layer of shale or carbonate mud of a sabkha, it will become an oil reservoir. In other instances, the source of the oil will be a shale that is below the carbonate rocks, and the oil will migrate upward into this reservoir.\n\n\nReference: John M Hunt, 1996, "Petroleum Geochemistry and Geology", W.H. Freeman & Co: New York. 743 pp.\n\nI'm a petroleum geologist.