Up to:  Biker's CafeThis should be a good place for all purpose talks, better than interleaving our discussions with "Time Trial Champions" comments.
BikerBrian | PoliticsWow! I stirred up a hornets nest by bringing up politics. Sorry guys, you can blame me. 
Let me start by saying that I am in complete agreement with Vega's last post in the GC thread (this discussion has now been moved to its own thread).
As Kris said, we each have our own personal beliefs about political (and religious) issues, so there is no sense trying to persuade each other.
However, I do need to add my 2 cents to Xuzz's comments. Regarding taxes: Even under the current "Bush system", people who earn more still pay WAY more than anyone else (actual and percentage). The top 5% earn 31.99% of all wages, but pay 53.25% of all income taxes. The top 50% pay 96.03% of all income taxes. The bottom 50% are paying a tiny bit of the taxes (3.97%), so you can't give them much of a tax cut by definition. Yet these are the people that Democrats claim to want to give tax cuts. Remember this the next time you hear the "tax cuts for the rich" business. Understand that the so-called rich are about the only ones paying taxes anymore.
The tax cuts have been unfairly labeled by the media to imply that they only help the rich, but that's crap. The "rich" are just being allowed to keep more of their own money. As Vega so eloquently put it, the better off they (and their companies) are, the better off everyone else will be. It is a terrible idea to punish success. If taxes are raised on businesses and employers, they will simply pass this burden on to customers and employees.
As for this election, we will have to agree to disagree if you (Xuzz) think Obama (who has the most liberal record in the U.S. Senate -  http://nj.nationaljou rnal.com/voteratings/) is better suited to run our country and unite it than McCain (who has a proven track record of working together with members from both parties).
Either way, our votes in CA and TN won't matter anyway. Obama will get California's electoral votes and McCain will get Tennessee's. There will be very little campaign money spent in either state. |
| Mr.pickle. |  | | | Gus |  |  | So because of an unsubstantiated piece of written evidence, which you haappen to believe in, you conclude that a theory with a great deal of backing behind it is false? I LOVE your logic there. If you want great examples of evolution in action (which you won't) then check the October edition of the New Scientist (can't remember which one, as there were 4 editions in Ocotber, but reading 4 title pages to judge which one shouldn't be too hard). It illustrates examples of features animals have developed which serve no practical purpose at present, but indicate an intermediary stage in evolution. A classic example of this would be Archaeopterix (I doubt if I spelled that right). This creature is, in terms of its basic structure, a bird, but has dinousaur like characteristics, such as the teeth in its beak. This supports the theory that the present day "raptors" (predatory bird family) are descended from the "bird hipped" dinosaurs (I forget the technical term).
As to your reference to a great flood, there were certainly numerous floods throughout huge regions, as the catastrophic tsunami in 2004 so violently demonstrated. It is also a widely held view that the Mediterranean was a barren desert, before being flooded, and later draining again. I have little doubt that the great flood described in the bible did occur, but I am sure that the fact that it covered the entire world is blatant hyperbole. The fact that some sedimentary layers are "mixed up" is to do with a function called plate tectonics, all to do with the fact that te surface, or crust of the planet is in fact floating on a see of magma, and the plates slip over these, crashing into each other. This buckles the layers of rock as they collide, jumbling up the layers.
Finally, I come to the behemoth (bohemeth? I hope that's what your talking about, if it isn't, sorry, my bible knowledge isn't up to scratch). Now I was under the impression that this gargantuan creature was water dwelling (again correct me if I'm wrong). To clarify: there was not a single species of dinosaur that lived exclusively in the water. There were numerous marine reptiles, which you may be alluding to, such as Lipleudodon (a 25 metre long carnivore that existed toward the end of the Jurassic period). My point is this: don't try and state facts without knowing them. When I am unsure, I at least have the decency to admit that my knowledge is not certain, but you trot out your information as fact. Has it occured to you that this fearful monster could be anything from a whale to a giant squid? But no, of course it must be that it was a dinosaur that existed thousands of years ago, not millions.
In short, there is too much information in favour of the theory of evolution to discount it (in my opinion). If you don't want to believe it, or have an alternate theory, I don't have a problem with that.
One last thing...what is an evolutionist? I have heard of biologists, paleontologists, and geologists who agree about the theory of evolution, but never an evolutionist. I guess you mean a paleontologist, as they are the ones to talk to about bones. Mind telling me where you found the story? That's not a bitter cynical jibe at the story, I actually want to hear it.
I have more to say, and more time to spend on it, but I already sound like an arrogant self-assured jerk, so I think I'll shut up now.
Sorry if this sounded like a rant, I genuinely hope I didn't offend anyone, and you are more than welcome to any faith you care to believe in...just thought I'd throw in my 2 cents.
Great to see these debates on BoD! |
| | mike flips |  | | PIckle, did you seriously just make up random theories in order to make yourself sound dumb?
Look how many rich arabs there are in the middle east. Way richer than the people you mentioned in the US. How does yout "theory" explain that?
Or how about the fact that china is currently emerging as the new world powerhouse? Is sit cause they are all secretly christian? Or are those just rumours and china is really not doing so well.
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| | Gus | | | Sorry for the double post, but I have just finshed reading Vega's post. You ask why monkeys are not evolving anymore. The answer is simple - they are. We are not finished, perfect examples of a fully evolved ape, we simply split from a common ancestor some time ago (I cannot^remember the number off the top of my head). We have not finished evolving ourselves. There is a huge misconception that evolution only occurs if the adaption is beneficial. This is not at all the case. DNA is often subject to mutations, which may not be harmful to us. This alteration in our genetic make up may not do us any good, but if it does not lessen our chances of passnig on our genes, then it is entirely possible that this adaptation will take root. Thi is known as genetic drift, and works in conjunction with natural selection. If the adaptation is beneficial to the chances of passing on our genes, it can take hold, if it does nothing, it can still continue through the gene pool. It is for this reason that, although natural selection amongst humans is lessening (vaccines helping us to survive, our wonderful medicines that save many lives, our societies that seek to protect those who cannot fend for themselves), evolution continues, although to a lesser degree.
As to the between time: Archaeopterix (please don't argue its a fake). Again, I point in the direction of the New Scientist magazine. If I have the time and energy, I will post a link if anyone is interested.
I will admit Vega, your 5th point has me stumped, and all I can do is point to the evidence of statistical probability. In an infinite universe, anything that can happen will happen, so we are simply part of a probability curve. I know that's a pretty lame argument, but it's the only one that I can reasonably think of.
I don't entirely understand your 5th point. The chances of us living at any given point in our planets history are very low, but we certainly will live there at some point, and the chances of it being at any specific point are all equal (ignoring the time taken for the atmosphere to develope, and water to be formed). I hope we don't live in a robotic society, but the way things are going, I fear that that is where we will end up.
We invented abstract concepts like right, wrong, morality, justice, and so many others, because to our society, they are necessary. But a male lion that kills the cubs in a pride he has taken over is doing something that we percieve as wrong, yet is only natural to them. These concepts only came about as a result of the increasingly comple nature of our societies.
I would like to believe that there is something out there, some point to everything, but I simply cannot have faith in something unproven. I realise that if there is proof, faith is superfluous anyway, so that's a bit of a problem for me. Maybe as I grow older I will be able to accept things on trust and belief, but at present I am very cynical, and will challenge opinions unless they are proven to my satisfaction. |
| | mike flips | | | Vega - technology is the answer. We finally advanced as a society into the technological era. That is why everything has been concentrated into the last 100 years. Machines give us the ability to do what we did 1000 years ago but we can not do it 1000x more efficiently. We can build a city within years not centuries. We can move mountains if we need to. The world is different because of technology and that is the sole reason it seams like we are "at the end" because no one ever capitalized on technology until recently.
And as for the evolution. This whole process of evolution is one that spans MILLIONS or even BILLIONS of years. Yet we have only been able to document the last few hundred which is insignificant in the long run. That is why humans have not "changed" recently. It would be many many more thousands of years before you would begin to noticed any major changes because evolution is a long process.
But yes point #5 - Gus' answer is interesting but its hard to believe there isnt something else that played a part.
But what about the rest of the universe. Theres billions of stars and many more plants and suns and moons.... how do we know there is nothing there. |
| | Vega |  | | Then you shall ROT IN HELL Gus! .......
Ha ha. Just kidding everyone. Scared you didn't I?
No I am not that type of so called "Christian". That's hateful bigotry, and it clashes with Christianity.
Anyway, it is a shame that you are cynical about faith in the unseen. That's not "entirely" your fault.
But it is your choice to believe what you will. That's free will in exercise. And I will respect that.
As for your comment about morality, animals are outside of accountability for moral choices.
Animals do not have free will. Only humans do. Lions cannot be compared to humans in this way.
As for my point #6, what I mean is that the curve of change must have quite the spike in the years 1000-2008.
So much has happened over the last few hundred years in our society. It would be very disproportionate.
Now I know that advancements in technology begets advances in our society, so it becomes a snowball effect.
But I just think it's supremely odd that after billions of years, here we are, advancing on earth at an amazing rate suddenly.
Why do people from hundreds of years ago look just like the people of today? Why are they not closer to apes?
Why didn't more things happen in the billions of years before our generations over the last 3000-4000 years?
Seems like everything is culminating to now. I believe the earth is between 6000-8000 years old.
(taken from estimated generational time periods dating back through the old testament)
I believe wholeheartedly that the scientific 'proof' behind the way they date things is false and inaccurate; heavily flawed.
I think you'll find it quite surprising that I partly believe in the idea of "evolution".
The part I believe is that we are always 'evolving', but not in the way that the theory on evolution suggests.
I believe God created everything, and we are evolving from his creations, but still within the boundaries of his intentions.
One intention being that man was created in his image from the beginning. Not as an ape. |
| | Gus | | | Well I can't argue with that, as it relies on changing your faith, which I doubt I could do, even if I wanted to. I respect your opinion, I respect the way you state it, without going nuts on me, and I agree that if the world is 6,000-8,000 years old, then yes things are culminating. I don't believe it myself, and my theory suits my beliefs perfectly, and I am at least satisfied with it. I hope the same is true for you. It is pickle who I have my dispute with, and his annoying statements... |
| | Mr.pickle. | | | Mike, about china. USA is currently losing standers, Praying in school is almost illegal, as is carrying a bible, losing all moral. hence why we are currently dropping as the world powerhouse. Why china? I dont rightly know but Satan has power.. hes pathetic compared to God but he has power on earth enuph to accomplish a few things. Look at the nazis, they nearly conqured all of euruop, I cannot say they were christian. But Good always wins in the end.
The middle east is where we get oil as of present. Hence there have to be rich people there who are harvesting all of it duh! I dident say it was correct in ALL cases I said MOST there is in fact a large difference. Not ALL succsesfull busnesses are christian simply most.
My theory on dinosours was simply becuase I personally like that one, I did not mean to spark an argument about that particular theory. I dont evan belive it myself, I simply think it is possible. I like to share theory's because dinosours are one of my favorate subjects. What about your theory mike? You said that God was to stupid to know the difference beetween a day and a billion years When it said clearly in genises "and the evening and the morning were the first day" It sais simular to that at the end of every single other day of creation. Not anything along the lines of "Several evenings and mornings were the next day"
I think your theory makes you look much stupider than mine
GUS!! I am suprised we brought you into this BUT OK! The more the merrior
The Bohemeth! It was I belive(havent read that chapter in a while) a amphibious creature. It may have been all water, or simply a land animal, I will look it up tonite and check,I will post what it sais tonite sometime...
The FLOOD There is only one layer that covers the ENTIRE earth that sais there was probly a giant earth covering flood.
"So because of an unsubstantiated piece of written evidence, which you haappen to believe in, you conclude that a theory with a great deal of backing behind it is false?"
Mike himself said the old testemate was one of the most reliable sorcess for true history. If you deny that, I am sorry but you havent lookd at your information correctly. and if you have and still deny it, I am sorry but you are not very smart.
And evolutionist is someone who takes evolution as fact and ignores all the obvios evedence it is totaly bogus, and doesent evan consider that they could be wrong. As where Vega and I and alot of other christians have read much acliamed books from either side, and then made our choice.
Where did I get that story?
I cant rightly recall... Honestly..I think it was some creation magazine, tho I dont remember which one.. But I will look it up and see if I can figer out where I got it. and btw if you can reference an evolutionist magazine I by golly can reference a creation magazine. which is filled with mostly facts, as where evolutionists magazignse are filled with hypothesisses. I am sure youl say that magazing is not evolutionist but it clearly is. It said thos animals indecate an early stage of evolution. They present it as a fact. When in fact it is really just a gess that it MIGHT be a early stage of evolution,not a fact.
There has been no missing link found, NONE whatsoever! they dont exist. All of the supposed missing links turned out to be fakes! If evolution were true we would defenattly have missing link fossils. Yet there are NONE! IF there were ANY at all Then it would be possible but there arent!
We did not invent right and wrong Gus I am kinda suprised you would say something so insane
Please Vega, or BB or anyone besides me, elaborate on what they said I am not good at it.....I know alot of facts but I am a horrible writer and dont know how to put them in written words. |
| | Mr.pickle. | | | WOW everone is typing at the same time |
| | Vega | | | Gus,
I have an interesting question (kind of a side skew in a way). But you'll find that there is a bit of depth behind my question if you understand me correctly.
You say above.... "if I wanted to". My question to you is 2 parts. Do you want to? And if you do, what's your motivation? |
| | Mr.pickle. | | | I looked up the bohemeth.
Job Chapter 40 verse 15-24.
15 “Look now at the behemoth,[a] which I made along with you;
He eats grass like an ox.
16 See now, his strength is in his hips,
And his power is in his stomach muscles.
17 He moves his tail like a cedar;
The sinews of his thighs are tightly knit.
18 His bones are like beams of bronze,
His ribs like bars of iron.
19 He is the first of the ways of God;
Only He who made him can bring near His sword.
20 Surely the mountains yield food for him,
And all the beasts of the field play there.
21 He lies under the lotus trees,
In a covert of reeds and marsh.
22 The lotus trees cover him with their shade;
The willows by the brook surround him.
23 Indeed the river may rage,
Yet he is not disturbed;
He is confident, though the Jordan gushes into his mouth,
24 Though he takes it in his eyes,
Or one pierces his nose with a snare.
So from that it sounds as tho he may be an amphibian or a complete land animal, as he eats grass. Definatly not your average creature.
I also read into the next chapter. About the leviathen, This was definatly a land animal, more of a dragon from the sound of it.. heres a link to chapter 41.
http://www.biblegatew ay.com/passage/?search=job%2041:1-60;& version=50;
That has all of chapter 41 on it(thirty somethin verses) I can post it here if you like I but I figer you all would complain about another huge post...but I can do it if you like, as the Bible goes its not really that long of a chapter. But if any of you read that, I dont see how you can deny humans and dinosours(or dragons, which were a sort of dinosour I gess)lived at the same time. big IF tho, I doubt any of you will actully click that link and read the whole chapter... |
| | Mr.pickle. | | | hmm re reading that..I gess its really the leviathen I was talking about not the bohemeth...they both could be dinosours, but the bohemeth mentions nothing of scales, as where the leviathen does...
in fact I am gonna go ahead and post chapter 41 as well...because you guys wont click the link...
Job Chapter 41.
1 “Can you draw out Leviathan[a] with a hook,
Or snare his tongue with a line which you lower?
2 Can you put a reed through his nose,
Or pierce his jaw with a hook?
3 Will he make many supplications to you?
Will he speak softly to you?
4 Will he make a covenant with you?
Will you take him as a servant forever?
5 Will you play with him as with a bird,
Or will you leash him for your maidens?
6 Will your companions make a banquet[b] of him?
Will they apportion him among the merchants?
7 Can you fill his skin with harpoons,
Or his head with fishing spears?
8 Lay your hand on him;
Remember the battle—
Never do it again!
9 Indeed, any hope of overcoming him is false;
Shall one not be overwhelmed at the sight of him?
10 No one is so fierce that he would dare stir him up.
Who then is able to stand against Me?
11 Who has preceded Me, that I should pay him?
Everything under heaven is Mine.
12 “I will not conceal[c] his limbs,
His mighty power, or his graceful proportions.
13 Who can remove his outer coat?
Who can approach him with a double bridle?
14 Who can open the doors of his face,
With his terrible teeth all around?
15 His rows of scales are his pride,
Shut up tightly as with a seal;
16 One is so near another
That no air can come between them;
17 They are joined one to another,
They stick together and cannot be parted.
18 His sneezings flash forth light,
And his eyes are like the eyelids of the morning.
19 Out of his mouth go burning lights;
Sparks of fire shoot out.
20 Smoke goes out of his nostrils,
As from a boiling pot and burning rushes.
21 His breath kindles coals,
And a flame goes out of his mouth.
22 Strength dwells in his neck,
And sorrow dances before him.
23 The folds of his flesh are joined together;
They are firm on him and cannot be moved.
24 His heart is as hard as stone,
Even as hard as the lower millstone.
25 When he raises himself up, the mighty are afraid;
Because of his crashings they are beside[d] themselves.
26 Though the sword reaches him, it cannot avail;
Nor does spear, dart, or javelin.
27 He regards iron as straw,
And bronze as rotten wood.
28 The arrow cannot make him flee;
Slingstones become like stubble to him.
29 Darts are regarded as straw;
He laughs at the threat of javelins.
30 His undersides are like sharp potsherds;
He spreads pointed marks in the mire.
31 He makes the deep boil like a pot;
He makes the sea like a pot of ointment.
32 He leaves a shining wake behind him;
One would think the deep had white hair.
33 On earth there is nothing like him,
Which is made without fear.
34 He beholds every high thing;
He is king over all the children of pride.”
That sounds like a fire breathing dinosour to me, decide for your self tho |
| | BikerBrian | | | I am enjoying this debate, because the more everyone else types, the more net playing time I get .
As for my beliefs: I believe that God created everything. As Vega said, things are way too complex just to "happen" or evolve. I spend a lot of time outdoors on Boy Scout outings with my son. Every time I see a star-lit night or a beautiful sunset, it only strengthens my faith.
Speaking of Boy Scouts, Reverence towards God is a major part of the program. The Boy Scouts of America is very tolerant of differing faiths, but you cannot be an atheist and advance to the rank of Eagle Scout.
As for faith (to commit oneself to act based on self experience to warrant belief, but without absolute proof), I would like to have all of the answers too. If we could prove everything, there would be no need for faith.
I believe in the Old and New Testaments of the Bible. I believe that there is a heaven and that Jesus came to earth, spent time here as a human, and died to provide a way for us to get there. I believe that God gave us a free will and we can choose to accept him or not.
I am 36 years old and I've chosen to live my life under this premise and as for me and my house, we will serve the Lord. I feel that I've been extremely blessed as a result of my devotion to my faith. I have a beautiful wife, great kids, and more than my fair share of earthly possessions. Don't get me wrong here, my happiness is not dependent on my family or possessions; it is a result of the hope I have that this (my few years on earth) isn't all there is.
When I die, if I've been wrong all along and there is no heaven (being in the presence of God), I will have no regrets for the way that I've chosen to live my life. I would much rather be wrong in this way than to end up apart from God after death.
For those of you who believe that your time on earth is all you get, stop wasting your time playing BoD and get to living! |
| | Mr.pickle. | | | Well said Biker Brian, well said. |
| | BikerBrian | | | As for dinosaurs, click on the following link for undeniable proof that humans and dinosaurs roamed the planet at the same time (that is, if you believe the theory that humans created automobiles):
 Jurassic Parking Time Trial |
| | Mr.pickle. | | | | Kristopher |  | | | mike flips | | | man im making levels but not at that rate.
Pickle, you are telling me you took a pencil and drew what you read about in that passage and came up with a dinosaur?
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| | Xuzz |  | | I have abosolutely no way of replying to all that, so ill only quote one thing for right now .
Vega - "For evolution facts, most of the numbers and statistics about carbon dating and scientific data have been proven to be bogus. These dating methods have failed miserably on numerous occasions... and they always seem to just glaze over that. "
I will now quote again what I quoted last time :
"How Old Is The Earth, And How Do We Know?
The generally accepted age for the Earth and the rest of the solar system is about 4.55 billion years (plus or minus about 1%). This value is derived from several different lines of evidence.
Unfortunately, the age cannot be computed directly from material that is solely from the Earth. There is evidence that energy from the Earth's accumulation caused the surface to be molten. Further, the processes of erosion and crustal recycling have apparently destroyed all of the earliest surface.
The oldest rocks which have been found so far (on the Earth) date to about 3.8 to 3.9 billion years ago (by several radiometric dating methods). Some of these rocks are sedimentary, and include minerals which are themselves as old as 4.1 to 4.2 billion years. Rocks of this age are relatively rare, however rocks that are at least 3.5 billion years in age have been found on North America, Greenland, Australia, Africa, and Asia.
While these values do not compute an age for the Earth, they do establish a lower limit (the Earth must be at least as old as any formation on it). This lower limit is at least concordant with the independently derived figure of 4.55 billion years for the Earth's actual age.
The most direct means for calculating the Earth's age is a Pb/Pb isochron age, derived from samples of the Earth and meteorites. This involves measurement of three isotopes of lead (Pb-206, Pb-207, and either Pb-208 or Pb-204). A plot is constructed of Pb-206/Pb-204 versus Pb-207/Pb-204.
If the solar system formed from a common pool of matter, which was uniformly distributed in terms of Pb isotope ratios, then the initial plots for all objects from that pool of matter would fall on a single point.
Over time, the amounts of Pb-206 and Pb-207 will change in some samples, as these isotopes are decay end-products of uranium decay (U-238 decays to Pb-206, and U-235 decays to Pb-207). This causes the data points to separate from each other. The higher the uranium-to-lead ratio of a rock, the more the Pb-206/Pb-204 and Pb-207/Pb-204 values will change with time.
If the source of the solar system was also uniformly distributed with respect to uranium isotope ratios, then the data points will always fall on a single line. And from the slope of the line we can compute the amount of time which has passed since the pool of matter became separated into individual objects. See the Isochron Dating FAQ or Faure (1986, chapter 18) for technical detail.
A young-Earther would object to all of the "assumptions" listed above. However, the test for these assumptions is the plot of the data itself. The actual underlying assumption is that, if those requirements have not been met, there is no reason for the data points to fall on a line."
Wikipedia says, "This age has been determined by radiometric age dating of meteorite material[2] and is consistent with the ages of the oldest-known terrestrial and lunar samples."
Radiometric age dating (Wikipedia as well): "Fundamentals of radiometric dating
All ordinary matter is made up of combinations of chemical elements, each with its own atomic number, indicating the number of protons in the atomic nucleus. Additionally, elements may exist in different isotopes, with each isotope of an element differing in the number of neutrons in the nucleus. A particular isotope of a particular element is called a nuclide. Some nuclides are inherently unstable. That is, at some point in time, an atom of such a nuclide will spontaneously transform into a different nuclide. This transformation may be accomplished in a number of different ways, including radioactive decay, either by emission of particles (usually electrons (beta decay), positrons or alpha particles) or by spontaneous fission, and electron capture.
While the moment in time at which a particular nucleus decays is unpredictable, a collection of atoms of a radioactive nuclide decays exponentially at a rate described by a parameter known as the half-life, usually given in units of years when discussing dating techniques. After one half-life has elapsed, one half of the atoms of the nuclide in question will have decayed into a "daughter" nuclide or decay product. In many cases, the daughter nuclide itself is radioactive, resulting in a decay chain, eventually ending with the formation of a stable (nonradioactive) daughter nuclide; each step in such a chain is characterized by a distinct half-life. In these cases, usually the half-life of interest in radiometric dating is the longest one in the chain, which is the rate-limiting factor in the ultimate transformation of the radioactive nuclide into its stable daughter. Isotopic systems that have been exploited for radiometric dating have half-lives ranging from only about 10 years (e.g., tritium) to over 100 billion years (e.g., Samarium-147).
In general, the half-life of a nuclide depends solely on its nuclear properties; it is not affected[2] by external factors such as temperature, pressure, chemical environment, or presence of a magnetic or electric field. (For some nuclides which decay by the process of electron capture, such as Beryllium-7, Strontium-85, and Zirconium-89, the decay rate may be slightly affected by local electron density, therefore these isotopes may not be as suitable for radiometric dating.) But in general, the half-life of any nuclide is essentially a constant. Therefore, in any material containing a radioactive nuclide, the proportion of the original nuclide to its decay product(s) changes in a predictable way as the original nuclide decays over time. This predictability allows the relative abundances of related nuclides to be used as a clock that measures the time from the incorporation of the original nuclide(s) into a material to the present.
The processes that form specific materials are often conveniently selective as to what elements they incorporate during their formation. In the simplest case, the material will incorporate a parent nuclide and reject the daughter nuclide. In this case, the only atoms of the daughter nuclide present in a sample must have been deposited by radioactive decay since the sample formed. When a material incorporates both the parent and daughter nuclides at the time of formation, a correction must be made for the initial proportion of the radioactive substance and its daughter; generally this is done by construction of an isochron, e.g. in Rubidium-strontium dating.
Accurate radiometric dating generally requires that neither the parent nuclide nor the daughter product can enter or leave the material after its formation, that the parent has a long enough half-life that it will still be present in significant amounts at the time of measurement (except as described below under "Dating with shortlived extinct radionuclides"), the half-life of the parent is accurately known, and enough of the daughter product is produced to be accurately measured and distinguished from the initial amount of the daughter present in the material. The procedures used to isolate and analyze the parent and daughter nuclides must be precise and accurate. This normally involves isotope ratio mass spectrometry[3]
[edit] Blocking temperature
If a material that selectively rejects the daughter nuclide is heated, any daughter nuclides that have been accumulated over time will be lost through diffusion, setting the isotopic "clock" to zero. The temperature at which this happens is known as the blocking temperature or closure temperature and is specific to a particular material and isotopic system. These temperatures are experimentally determined in the lab by artificially resetting sample minerals using a high-temperature furnace.
[edit] The age equation
Considering that radioactive parent elements decay to stable daughter elements [4], the mathematical expression that relates radioactive decay to geologic time, called the age equation, is [5]:
where
t = age of the sample
D = number of atoms of the daughter isotope in the sample
P = number of atoms of the parent isotope in the sample
ë = decay constant of the parent isotope
ln = natural logarithm
The decay constant (or rate of decay[6]) is the fraction of a number of atoms of a radioactive nuclide that disintegrates in a unit of time. The decay constant is inversely proportional to the radioactive half-life of the parent isotope." |
| | Xuzz | | |
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http://upload.wikimed ia.org/math/5/7/4/574 5038b9e2e8de753a5d12a2d52b697.png
