Explain the term rock dating?
372960
Well, it could be a date with Mick Jagger (from the Rolling Stones) or more likely it is using the various isotopes of elements found in a sample of stone to estimate its age. Say a stone was found with 50% of its original uranium in it. Uranium has a half life of 4.5 billion years so the stone would have passed one half life and would have an age of 4.5 billion years.  If only 25% of the original uranium were left, then 2 half lives or 9.0 billion years would have passed since the stone was created.
650039
what a troubling Q: but i agree with that 6k yrs of this planet... the carbon dating is nothing but a paleontological gibberish... the world is not a million or so yrs old... mybe they just need a lil more tyme checking the computations... one million yr wud mean a day or a week in the christian "dating" watdayathink?? (,"}
996967
Radioactive dating is dating using the decay of naturally occuring biologically acive materials. The most common is carbon. Carbon 14 is created at a more or less constant rate in the environment and then decays, so is found at a fixed proportion in relation to carbon 12. This is the proportion found in living organisms. When they die, they take up no more carbon, so the carbon 14 decay causes the ratio to change in a way that can be used for dating..\n\nNo. The moon has moved 90 degrees in relation to the earth and so is now in quadrature with the sun.\n\nThe solar cycle is the cyclical variation in sun spots on the surface of the sun. Sunspots are caused by loops of magentic flux. Their reduction is caused by shedding entagled loops of field.\n\nComets tails point away from the sun because of the solar wind. Far from the sun comets have no tails.\n\nThe corona is hot but thin. So light from it is swamped by light from the rest of the sun usually. In an eclipse the moon blocks light from the rest of the sun.
757722
Well you can date in-situ rocks relative to others by a few basic principles such as fossil evidence and sequence stratigraphy (if one rock is 'cut' by another then the it is older).\nIf you have an entire sequence of rocks right up to the present time the you could use deposition rates to calculate age but I wouldn't rely on it.\n\nTo calculate the age of a single sample of rock that is not in-situ I don't think is possible.  We use radioactivity because we know the rate at which it changes over time.  We understand the passing of time because things change.  If you were put to sleep in a dark room with no contact with the outside world then after about 1 week you would have no idea how much time had passed when you woke because you wouldn't have a point of reference.
853493
Dendrochronology or tree-ring dating is the method of scientific dating based on the analysis of tree-ring growth patterns. This technique was invented and developed during the 20th century originally by A. E. Douglass, the founder of the Laboratory of Tree-Ring Research at the University of Arizona. The technique can date wood to exact calendar years.\n\nclick here:http://en.wikipedia.org/wiki/Dendrochronology#Overview
657093
Rocks tell the story of the Earth. The Earth is made of rock, from the tallest mountains to the floor of the deepest ocean. Thousands of different types of rocks and minerals have been found on Earth. Most rocks at the Earth's surface are formed from only eight elements (oxygen, silicon, aluminum, iron, magnesium, calcium, potassium, and sodium), but these elements are combined in a number of ways to make rocks that are very different.\nRocks are continually changing. Wind and water wear them down and carry bits of rock away; the tiny particles accumulate in a lake or ocean and harden into rock again. The oldest rock that has ever been found is more than 3.9 billion years old. The Earth itself is at least 4.5 billion years old, but rocks from the beginning of Earth's history have changed so much from their original form that they have become new kinds of rock. By studying how rocks form and change, scientists have built a solid understanding of the Earth we live on and its long history.
787241
Bowen's reaction series is what you're looking for.\n\nIn a nutshell, the rate of cooling, temperature, and magma composition determine which minerals form and the ultimate rock type.  The links provide more information.
849041
A rock is a naturally occurring aggregate of minerals and/or mineraloids. Rocks are classified by mineral and chemical composition, by the texture of the constituent particles and by the processes that formed them. These indicators separate rocks into igneous, sedimentary and metamorphic. They may also be classified according to grain size, in the case of conglomerates and breccias or in the case of individual stones.\n\nMinerals are natural compounds formed through geological processes. The term "mineral" encompasses not only the material's chemical composition, but also the mineral's structure. Minerals range in composition from pure elements and simple salts to very complex silicates with thousands of known forms (organic compounds are excluded). The study of minerals is called mineralogy.
564371
1. Because carbon-14 has a half-life of only 5,730 years.  So after 60,000 years there is not enough left to measure reliably.  That's why carbon dating is *not* used for fossils (despite what many people, including most creationists, think) ... there are dozens of other techniques used for dating fossils and rocks.\n\n2. Because it only works on things that were eating or breathing carbon ... i.e. things that were once alive.  (So it is useless for rocks, or asteroids, much less stars.)\n\n3. Because you actually need a sample of what you are dating ... so you could not use it to date things like distant stars or galaxies (the things that go back to the Big Bang).
664010
carbon dating cannot be used for very old fossils. Radioactive dating is a better method used extensively by geologists. Carbon 14 is fairly reliable for fossils that are not too old.
801085
Classification \nClastic \nBiogenic \nPrecipitate \n\nread and learn --> http://en.wikipedia.org/wiki/Sedimentary_rock#Classification
157318
For something to be dated using a radioactive technique, it has to include radioactive materials. Granite is radioactive (see attached), but its level of radioactivity is usually quite low (no more than any other natural material). This makes dating granite a bit challenging, but it can be done (see example in 2nd reference). Granite usually contains a little U-238 which does decay, and this can be used to date granite. It also contains some Rb-87 which decays into Sr-87, and the Rb-Sr dating techniques can be used to date granite.
587464
Rock is a naturally occurring aggregate of minerals and/or mineraloids. Rocks are classified by mineral and chemical composition; the texture of the constituent particles; and also by the processes that formed them. These indicators separate rocks into igneous, sedimentary, and metamorphic.\n\nMinerals are natural compounds formed through geological processes. The term "mineral" encompasses not only the material's chemical composition, but also the mineral's structure. Minerals range in composition from pure elements and simple salts to very complex silicates with thousands of known forms (organic compounds are usually excluded)
153391
I'm assuming that that refers to giving the age of two things relative to one another, rather than identifying the absolute ages of things.  For instance, when you take two trees that lived in similar times and places, you can look at the width of the tree rings to get an idea as to the conditions (especially moisture) during a given year.  If you have two such wood samples, you should be able to see a pattern between the two.  Using taht information, you could count rings and figure out how much older one piece of wood was relative to the other.  But without knowing the year the trees dies, or without knowing the particular calendar years behind the droughts, you wouldn't know that absolute age of either.  I'd imagine that there are similar things with radioisotope dating if you have a reason to think that the atmospheric conditions creating certain isotopes might change, but not knowing the exact concentrations at the time an organism lived.
382440
OMG!!!!\nYou rock girl-great research!
1076848
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.
968818
Shanna and Geo06 have got this just about right.  The only thing I can add is that radiocarbon dating can not be used for more than about 70,000 years ago, and is more accurate for living things that died within the last 8,000 years.\n\nMost geologists measure rock ages in millions, or even billions, of years, so the age of the earth and the age of almost all igneous rocks is well beyond the range of carbon dating.  On top of that, igneous rocks contain very little if any carbon,  so carbon dating is not applicable here.  \n\nSo the only thing carbon 14 can be used for is to determine the time that an exchange of carbon with the atmosphere stopped, ie, the death of a living thing - the third item on your list of choices for your homework.\n\nThe half life of C-14, the radioactive isotope of carbon, is about 5730 years.  Therefore, if you know the ratio between C-14 and C-12 in the atmosphere when the organism died, and you know the ratio now, the difference in the ratio can be calculated backwards, using the half life, to estimate when the organism died. \n\nAtmospheric C-14 has not been in a constant ratio with C-12, as previously thought, so there are some serious problems with the accuracy of C-14 dating.  The problem is that the natural ratio of the carbon isotopes in the atmosphere (carbon dioxide) varies because cosmic ray bombardment of the outer atmosphere produces C-14 but not C-12.  The ratio can be predicted accurately using the ratios in old trees, where the tree rings can be used to accurately determine the age of each ring with its annual ratio, with a maximum of about 8,000 years -that's how old the oldest trees are which can establish a reference ratio.\n\nDating of artifacts is a best guess, the best method is to measure the amount of lichens growing on them, or the age of carbon in ashes found in the same spot.