|
Register | Sign In |
|
QuickSearch
Thread ▼ Details |
Member (Idle past 1657 days) Posts: 20714 From: the other end of the sidewalk Joined: |
|
Thread Info
|
|
|
Author | Topic: The Law of Superposition and Devil's Hole and Old Earth Age | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
RAZD Member (Idle past 1657 days) Posts: 20714 From: the other end of the sidewalk Joined: |
The Law of Superposition quote: Instead of sedimentary layers, let's apply this law to the dense vein calcite formation found in Devil's Hole (Nevada), where the innermost layers had to be laid down first to form a base for later layers to deposit onto as they build up the dense vein calcite formation, so the deeper into the formation the older the calcite: Devil's Hole Data for Devil's Hole Core DH-11:
quote: They measured the age with radiometric decay products at 21 control points, and interpelated between them for samples where δ18O and δ13C were measured as indicators of climate. There is a table with the 284 samples by age with δ18O and δ13C values (the δ13C isotope is stable, unlike δ14C used for carbon dating).
Devils Hole, NevadaA Primer quote: Age Measurements Here we are interested in age versus depth within the calcite vein deposit. Here we have a series of data with three different pieces of information: calcite depth relative age, Thorium-230 content and Protactinium-231 content. The calcite relative age is corroborated by two independent radiometric methods. So what exactly do we have here? Ground water (aquifer discharge) flowing slowly through a cave formed tectonically in carbonate rock, depositing calcite and various other minerals and impurities on the wall, including elements that are soluble in water, such as trace levels of radioactive isotopes of uranium. These materials get deposited as the calcite forms, similar to the way sedimentary deposits trap organic deposits. The calcite builds up in a continous process, trapping the radioactive impurities and other material in their respective age related location. The calcite forms a solid rock matrix that holds these impurities in a position related to the time they were deposited in the calcite. Radioactive elements decay into other elements, and some of these are not soluble, and thus the presence of these insoluble daughter elements is evidence of decay of the soluble parent elements. These daughter elements are still trapped in the layers of calcite that the parent elements were deposition in, so their position also relates to the age of the daughter elements in the calcite layers. We are interested in two radioactive isotopes of these matrix constrained elements - thorium-230 and protactinium-231. Using the half-lives of thorium-230 (75,380 years) and protactinium-231 (32,760 years), we can draw the exponential curves for these isotopes (with % on the y-axis and time in k-yrs on the x axis, thorium in blue and protactinium in red): Like sedimentary layers, the law of superposition means that calcite depth is related to age, and this gives us a relative age system. We also note that Thorium-230 has a half-life of 75,380 years, while Protactinium-231 has a half-life of 32,760 years - less than half the half-life of Thorium-230. This means that layer by layer the ratio of Thorium-230 to Protactinium-231 is different:
So for these dates to be invalid there would have to be a mechanism that can layer by layer preferentially change the ratio of these two (elements\isotopes) within the solid calcite vein, in what is now stone. This also means that any fantasy about radioactive decay in the past being different than in the present, is invalid unless this changing ratio can be explained by a physical process, not fantasy. Enjoy Further information Thorium-230 Radiometric Dating
quote: See also Thorium - Wikipedia(7). Thorium-230 has a half-life of 75,380 years. Protactinium-231 http://www.ead.anl.gov/pub/doc/protactinium.pdf
quote: The U-235 to Pa-231 decay is from a different series than the U-234 to Th-230 decay, so the two are independent of each other. Again, as the Devil's Hole calcite was deposited after being dissolved in water, the Pa-231 in the calcite could only come from the decay of the parent U-235, giving an accurate measurement of the age of the layers of calcite. See also Protactinium - Wikipedia(6). Protactinium-231 has a half-life of 32,760 years. Radioactive Decay The radiation decay curve is exponential, with different results for different decay constants - the half-lives of the radioactive isotopes. Exponential decay - Wikipedia (4)
quote: Edited by RAZD, : .by our ability to understand Rebel☮American☆Zen☯Deist ... to learn ... to think ... to live ... to laugh ... to share. Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||
RAZD Member (Idle past 1657 days) Posts: 20714 From: the other end of the sidewalk Joined: |
quote: The dense calcite formation in Devil's Hole is a closed system: once trapped by the deposition onto the formation the radioactive impurities are covered by layer after layer of newer deposits. This means that radioactive impurities have nowhere to go, and thus they should be findable ... if they haven't decayed away. We know that there were deposits of carbon in the calcite because they were measuring the δ13C content at each sample depth. They were not measuring δ14C because it decays away after roughly 50,000 years, and once covered by calcite there is no way to replenish the 14C in the vein. This is one of several cosmogenic isotopes that would be deposited in the formation. This confirms that the calcite vein is older than 50,000 years, and this confirms that the earth is older that 50,000 years. Enjoyby our ability to understand Rebel☮American☆Zen☯Deist ... to learn ... to think ... to live ... to laugh ... to share. Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||
AdminPhat Inactive Member |
Thread copied to the The Law of Superposition and Devil's Hole and Old Earth Age thread in the Dates and Dating forum, this copy of the thread has been closed.
|
|
|
Do Nothing Button
Copyright 2001-2023 by EvC Forum, All Rights Reserved
Version 4.2
Innovative software from Qwixotic © 2024