Talk:Radiocarbon dating/Archive 3 - Wikipedia
From Wikipedia, the free encyclopedia. Jump to navigation Jump to search. Absolute dating is the process of determining an age on a specified chronology in archaeology and geology. Some scientists prefer the terms chronometric or calendar dating, as use of the word "absolute" implies an unwarranted certainty of accuracy. Techniques include tree rings in timbers. Oct 18, set to improve the accuracy of the dating technique, which could help to shed light Carbon dating is used to work out the age of organic material — in effect, any living thing. The technique hinges on carbon, a radioactive isotope of the element that, Sign up for Scientific American's free newsletters. From Wikipedia, the free encyclopedia. Jump to navigation Jump to search. Radiometric dating or radioactive dating is a technique used to date materials such as rocks or 1 Fundamentals. Radioactive decay; Accuracy of radiometric dating; Closure temperature; The age equation. 2 Modern dating methods.
A tiny minority of others do differ; so what? You appear to be debating for its own sake. Perhaps Radiocarbon After Four Decades ?
Other than that, I suspect there is just papers in peer-reviewed journals. And you had assumed that it would take me only minutes to comment on your changes.
You could make a section in which to list all the conferences, including the Nobel Symposium volume. The Nobel volume is interesting only for history-of-science purposes. You said that you wanted to include more references; I am entirely happy with that. Do you have constructive suggestions for useful things to read to learn more about 14C dating? It's not history of science. If not, then there is nothing to talk about. If you explain what the Dutch-language reference says in clear English though, then we can find English-language links that say the same thing—and cite them.
They are of crucial importance for understanding radiocarbon dating. You can find plenty of discussion about this topic. I do not know which other links you mean are missing. Some links were moved to other sections "See other" and "External links" or appeared to be wholly redundant.
Not in those who rather than read the article, use it as a tool and go to the references and the external links when they want to calibrate a date. I only know of one: This is not a program used by many people for good reason ; moreover, if readers want it, they can easily get it by following either the CalPal link which is still there or the radiocarbon. Having two links to CalPal looked almost like advertising.
RATE project - Wikipedia
It is only once. And where I and other that use it several times per day can find it. You appear to be playing a game that is inappropriate for Wikipedia.
I ask you to cease such actions. I expanded the acronym to avoid further confusion between oceanic agencies. Carbon dating can only be trusted for smaller dates, such as a few thousand years, because it is mroe logical to assume that less "stuff" has hapenned in the last 2 thousand years or so.
Then, read the section "calibration" of this article and ask yourself: The heading was confusing. Radiocarbon is used to date much more than archaeological samples, as said in the articles related to C The reader would get the impression that the simplified method works only for archaeological samples.
The simplified calculations proposed have a granularity of one half-life, i. BTW, such coarse method is described in the article about radiometric datingsee  Jclerman Also, the formula is not that important, because you really have to calibrate the ages via tree rings.
You are probably right that the formula unnecesarily intimidates people though.
Perhaps the discussion of the formula should be improved. Also, I like the example that you give at the end on your user page: I tried to shorten it but, in fact, I got it longer. I made some punctuation and other minor changes that migth be incorrect or unwanted Perhaps the table could have an extra row with the corresponding dates for each fraction, thus avoiding the mystery of the logs This is the way I introduce the concept to my beginning high school Chem 1 students as they haven't been exposed to rate laws and such and this is easier for them to grasp.
I use base 10 logs for them as it's easier for them to grasp most don't know what logs are and with a brief intro they can use another button on their calculators: The example giving non-integer half lives is important as it is simply the most common real world outcome I just picked a random fraction off the top of my head there.
You said that "we need a raw date to input into the calibration curves". We need the raw 14C measurement, true, but we do not need to do the exponential calcuation. Rather, the raw 14C measurement can be directly compared with the raw 14C ages in tree rings it is actually easier this way, because then the distributions are true Gaussian.
I'll be considering them when I make some minor edits to the sections in discussion. It will be later, probably overnight. I wonder if you could put a webcam in your classroom. I destroyed a little more your table, examples and text. See suggestions that I included between  I am not familiar with table editing, neither wiki or html. See also my comments below. And your non-integer n is a great idea.
See my suggestion for an extra example with a larger n. Also added one more column - just cause it would fit: The only problem I find with using the "easy" method is that my advanced chem students want to use it rather than the "book" rate constant eqn. Interesting result 'tho I can't say how accurate. I failed to understand your statement: Can you please explain this method and give a reference to it?.
Radiocarbon dating - Simple English Wikipedia, the free encyclopedia
Since to use calibration curves one needs to input a raw age or raw date value, I've expanded my current draft in progress to explain the experimental procedures to obtain such value before using a calibration curve. One of my problems was not to understand what do you mean by raw 14C measurement activity? Other statement I couldn't parse is: How different is this from a calibration curve? Many people will not understand it; among those people that do, they could find out what they need from the article on Exponential decay which is linked to from this article.
I preferred your previous proposed text! As for the term "raw", I'd used this because that is what you had used. So we do not need to use exponentials. Notice that I would not know what it means. I use "raw C14 date", "raw C14 age", "calibrated calendrical C14 date", "raw C14 radio activity", "net C14 radio activity", etc. Notice that only the "raw activity" is the result of a primary measurement.
All other quantities are calculated. The first time that the word "raw" was used was in your posting at I actually don't know what "raw" means in any context. Anyway, though, I think we might be better off letting this subject drop, and I will agree not to use "raw" anymore.
In fact, they grew up during six months of extensive exchanges with users from varied backgrounds. It still keeps growing in length due to the need to define the quantities we are using. Dormant volcanoes can also emit aged carbon. These effects are hard to predict—the town of Akrotirion Santoriniwas destroyed in a volcanic eruption thousands of years ago, but radiocarbon dates for objects recovered from the ruins of the town show surprisingly close agreement with dates derived from other means.
If the dates for Akrotiri are confirmed, it would indicate that the volcanic effect in this case was minimal. This is probably because the greater surface area of ocean in the southern hemisphere means that there is more carbon exchanged between the ocean and the atmosphere than in the north. Since the surface ocean is depleted in 14 C because of the marine effect, 14 C is removed from the southern atmosphere more quickly than in the north. Within a hemisphere, however, atmospheric mixing is apparently rapid enough that no such effect exists: Contamination with modern carbon causes a sample to appear to be younger than it really is: Radiation levels do not remain constant over time.
Fluctuating levels can skew results — for example, if an item went through several high radiation eras, thermoluminescence will return an older date for the item.
- RATE project
- Carbon Dating Gets a Reset
- Absolute dating
Many factors can spoil the sample before testing as well, exposing the sample to heat or direct light may cause some of the electrons to dissipate, causing the item to date younger. It cannot be used to accurately date a site on its own.
However, it can be used to confirm the antiquity of an item. Optically stimulated luminescence OSL [ edit ] Optically stimulated luminescence OSL dating constrains the time at which sediment was last exposed to light. During sediment transport, exposure to sunlight 'zeros' the luminescence signal.
Upon burial, the sediment accumulates a luminescence signal as natural ambient radiation gradually ionises the mineral grains. Careful sampling under dark conditions allows the sediment to be exposed to artificial light in the laboratory which releases the OSL signal. The amount of luminescence released is used to calculate the equivalent dose De that the sediment has acquired since deposition, which can be used in combination with the dose rate Dr to calculate the age.
Dendrochronology The growth rings of a tree at Bristol ZooEngland.