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Pass the pipe..


Steff

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QUOTE(Kid Gleason @ Nov 2, 2005 -> 02:50 PM)
It's odd. I LOVE Beer. I have a beer cellar and a dedicated beer fridge. It's a hobby.

 

I have smoked pot 3 or 4 times in my life and only been high twice.

 

I'm the first person to say alcohol should be illegal LONG before pot should be. It's just another example of how f***ed up the human race is. Ot atleast how f'ed up the US is.

i think someone admitting beer is a hobby is the first step to recovery :P

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QUOTE(sox4lifeinPA @ Nov 2, 2005 -> 10:45 PM)
Jim, a friend from my bible study lent me a three tape video set on defending creationism. I'm gonna take notes...impending evolution thread to come:)

oh s***. We better find a way that Juggs can't see it. :bang

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QUOTE(kapkomet @ Nov 2, 2005 -> 04:48 PM)
oh s***.  We better find a way that Juggs can't see it.  :bang

 

 

It's from a PM that I sent to Jim. I got "yelled" at by some of the guys in my study because I said I don't necessarily buy into what creationist scientist say. Carbon dating, for instance has been explained to me and I don't understand the big deal.

 

chaos will hopefully be averted, we'll see :)

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QUOTE(sox4lifeinPA @ Nov 2, 2005 -> 02:55 PM)
It's from a PM that I sent to Jim. I got "yelled" at by some of the guys in my study because I said I don't necessarily buy into what creationist scientist say. Carbon dating, for instance has been explained to me and I don't understand the big deal.

 

chaos will hopefully be averted, we'll see :)

Only anthropologists really care about "Carbon" dating.

 

You want the real fun of the earth...you need to talk about more general radiometric dating, using far more isotopes than just C-14.

 

Ooh I'm just itching for another quality evolution thread.

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QUOTE(Balta1701 @ Nov 2, 2005 -> 06:59 PM)
Only anthropologists really care about "Carbon" dating.

 

You want the real fun of the earth...you need to talk about more general radiometric dating, using far more isotopes than just C-14.

 

Ooh I'm just itching for another quality evolution thread.

I met a boy today who is a geo-chemist. He told me a lot of interesting research in that field

 

 

 

 

 

 

 

 

 

I changed the subject as fast as I could.

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QUOTE(Balta1701 @ Nov 2, 2005 -> 05:59 PM)
Only anthropologists really care about "Carbon" dating.

 

You want the real fun of the earth...you need to talk about more general radiometric dating, using far more isotopes than just C-14.

 

Ooh I'm just itching for another quality evolution thread.

Yeah, we went over that in the tutorial. I turmed PA onto the buauty that us U-235 for dating the really old stuff. Like Bea Arthur's lingerie, for example. :D

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QUOTE(FlaSoxxJim @ Nov 2, 2005 -> 03:02 PM)
Yeah, we went over that in the tutorial.  I turmed PA onto the buauty that us U-235 for dating the really old stuff.  Like Bea Arthur's lingerie, for example.  :D

Actually, it's both U235 and U238. They're vastly more powerful when you use them togehter, and you can measure them at the same time.

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QUOTE(FlaSoxxJim @ Nov 2, 2005 -> 05:02 PM)
Yeah, we went over that in the tutorial.  I turmed PA onto the buauty that us U-235 for dating the really old stuff.  Like Bea Arthur's lingerie, for example.  :D

 

shudder.... :bang for the record, I may just submit questions in a private forum. I haven't decided. If people are nice to me, then maybe...just maybe. :lol:

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QUOTE(Balta1701 @ Nov 2, 2005 -> 06:03 PM)
Actually, it's both U235 and U238.  They're vastly more powerful when you use them togehter, and you can measure them at the same time.

Do they both decay to Pb-207, or does U-238 have a distinct decay product? Is U-238's half-life also in the 700 my range?

 

Welcome to the Sex, Lies, and UberGeeks forum. :D

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QUOTE(FlaSoxxJim @ Nov 2, 2005 -> 05:08 PM)
Do they both decay to Pb-207, or does U-238 have a distinct decay product?  Is U-238's half-life also in the 700 my range?

 

Welcome to the Sex, Lies, and UberGeeks forum.  :D

 

Look, I come back and this place gets smarter...

 

 

I'll accept the key to SLaP now.

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QUOTE(FlaSoxxJim @ Nov 2, 2005 -> 03:08 PM)
Do they both decay to Pb-207, or does U-238 have a distinct decay product?  Is U-238's half-life also in the 700 my range?

 

Welcome to the Sex, Lies, and UberGeeks forum.  :D

Ok, you really want to get into it, let's get into it.

 

U 235, U238, and Th232 all decay to different isotopes of Lead. U238 goes to lead 206, U235 goes to Lead 207, and Th232 goes to lead 208.

 

Uranium and Lead are particularly useful since you can measure both of them using the same measurement - you don't have to go to any added lengths to isolate them, since they are the same chemical element. The only thing you need is a 2nd detector cup in your mass spec.

 

This gives a really nice benefit, in that you can use the fact that you have 2 different clocks in the same elements. Why? Because you can detect easily if something has contaminated your sample or if your sample has been altered since it was originally formed.

 

When both of the isotopes decay, they decay at different rates, producing an exponential curve if you compare the composition of 1 daughter isotope with the composition of the other. However, if you were to lose lead from your sample (a moderately common occurence in some systems), that lead loss event takes the form of a straight line towards the origin of that graph, since there is no real fractionantion between the 2 isotopes by mass - they both just head towards zero. From the point the sample becomes sealed again, you can resume using the exponential growth function.

 

This is remarkable, in that if you have a sample of another variety which has been contaminated or underwent a metamorphic alteration, it can completely wipe out the signal you really want to analyze. But with U-series data, you can actually account for metamorphic events, and get both the age of the alteration event and the age of the original formation of your sample.

 

U238 has a half life of about 4.5 billion years, so it's roughly an order of magnitude longer than U235. Th232 has a half life of about 15 billion years. So on all of those, we'd expect to see very measurable variations over geologic time.

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QUOTE(Balta1701 @ Nov 2, 2005 -> 06:18 PM)
U238 has a half life of about 4.5 billion years, so it's roughly an order of magnitude longer than U235.  Th232 has a half life of about 15 billion years.  So on all of those, we'd expect to see very measurable variations over geologic time.

 

But if the universe is only 10,000 years old, what's the point?

 

And thanks for the primer, it is appreciated and I can see why looking at all three together makes sense.

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QUOTE(Kid Gleason @ Nov 2, 2005 -> 06:48 PM)
O.K., for as quick as this tpoic changed to religion and whatnot, I think it's safe to say you are all high right now.  :ph34r:

 

Only on Soxtalk can a topic go from getting high to the half-life of different uranium atoms.... That's what I love about this place :P

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