Questions tagged [radioactivity]

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Does the relative abundance of radioactive isotopes reflect their half-lives?

In Radiometric Dating: A Christian Perspective, the author argues (persuasively, I think) in favor of the mainstream interpretation of radiometric dating (as opposed to the claims of young earth ...
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When Earth formed 4.5 × 10⁹ years ago, how much radiation did surface rocks emit?

When Earth formed $\approx 4.5 \times 10^9$ years ago, Earth's surface rocks emitted more radiation because they had more unstable isotopes. All short half-life isotopes decayed long ago, and the ...
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In radiometric isochron dating why is at t=0 D*/Dref=const but P/Dref not?

I am a physics graduate and trying to understand one of the assumptions made for isochron dating of rocks: at crystallization time of the rock, $t=0$, the ratio of the parent isotope to a stable ...
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Independent sources of information on radiation pollution in Europe

Bear with me if this is a wrong place to ask this question. I aksed this question on Physics at StackExchange and was told it will be more on topic here. Recent news show a fire has started close to ...
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Are hot springs in non-volcanic areas radioactive?

Hot springs in non-volcanic areas are attributed to the interaction of water with hot rocks deep in the earth's crust: In non-volcanic areas, the temperature of rocks within the Earth also ...
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How can radiometric dating of meteorites determine the age of the earth? Wouldn't this only determine the age of the decaying nuclide in each rock? [duplicate]

How can the radiometric dating of different meteorites determine the age of the earth? Wouldn't radioactive decay have already been occurring in all of those meteorites long before they hit earth? ...
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Is radiocarbon dating based on assumptions?

https://benpiper.com/2011/07/the-truth-about-carbon-dating/ The site above explains that Carbon-14 dating is based on a few assumptions, like to deduce the age of an organism by looking at the amount ...
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Potassum-Argon Dating and Proportions of Daughter Products in Potassium 40 Decay Channel

So Potassium 40 decays in such a way that roughly 89% of it becomes Calcium 40 and 11% of it becomes Argon 40. When they list these figures are they implying that after 1 half-life, of the 50% of the ...
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How do people determine initial ratio of the parent nuclide and daughter product in radiometric dating?

I understand that we have zircon crystals that prevent entering or leaving of nuclide or lead after forming. But how cand we understand what was the initial ratio?
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gamma-ray spectrum vs energy decay

I am going through An Introduction to Applied and Environmental Geophysics, a book by John Reynolds (2011), to better understand radiometrics and gamma-ray spectrometry. The author provides some ...
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Radiometric dating data sets

I am in the process of learning what sort of data is collected with radiometric dating techniques, used for absolute dating. It sounds like there are two primary ones: Radiocarbon dating (~50k year ...
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Where to start searching to find more radioactive minerals?

I'm pretty new to all this... I've recently purchased a Geiger counter, and am hoping to locate rocks like pitchblende and other radioactive minerals for my collection. I'm based in the North West ...
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Giem's article on carbon dating

I don't want to start any controversy. I'm just curious about what could professional geologists say about this paper, and what is it's current scientific status, since I couldn't find any serious ...
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Is there any correlation between Australia's uranium deposits and the unique animals?

Australian animals are very different than the rest of the world. I wonder if the radiation of Australia's Uranium deposits have anything to do with why animals uniquely evolved? For instance, ...
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How do we know how much Uranium was in any given sample when it was deposited?

Concerning "Uranium-series dating", also known as "Uranium-thorium dating". Uranium is present in deposits, "typically at levels of between a few parts per billion and few parts per million by ...
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Are Helium 3 and 4 being produced by earth's core?

J. Marvin Herndon claims that the evidence of the georeactor comes from 3He/4He ratios released to the oceans at the mid oceanic ridges. Georeactor-produced 3He/4He ratios are related to the extent of ...
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Does Earth's magnetic field arise from a fission reactor in its core?

I heard about the georeactor hypothesis (Herndon, 1993), which claims that there is a natural atomic fission reactor in the Earth's core giving rise to the geomagnetic field. Further, Herndon claims ...
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Rate of underground formation of carbon-14 by neutron capture

Carbon-14 constantly forms in the atmosphere due to neutron capture by nitrogen-14 and subsequent emission of a proton. Other less frequent mechanisms involving neutron capture by carbon-13 or oxygen ...
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Why can isotopes reflect the age of the Earth rather than the age of the supernova that created them?

Radiometric dating is based on heavier elements decaying into lighter elements, for example uranium decaying to lead. But wasn't all uranium in the Solar System created in one or more supernova? And ...
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Possible Effects of a Nuclear Reactor Breach in the Mediterranean

Double-barreled question which may not precisely belong here! Input nonetheless greatly appreciated. My question: To what extent would a nuclear reactor breach in the Mediterranean sea affect the ...
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Why does phosphate rock contain uranium?

I have been doing some research on the issue of phosphogypsum pollution. Phosphogypsum is a waste by-product formed with the "wet process" method of extraction of phosphoric acid out of ...
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Do fluctuations in radioactive isotope decay rates affect carbon dating techniques?

In 2010, Purdue University published a research paper[1] stating that their researchers had detected slight fluctuations in radioactive isotope decay rates "in synch with the rotation of the sun's ...
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Natural nuclear explosions

I'm aware of the Oklo reactor and other natural nuclear fission reactors, in which geological processes can lead to the formation of a sustained, self-regulating uranium fission reactor. Is it also ...
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How does radiogenic argon-40 get into the atmosphere?

There's an awful lot of argon in the atmosphere: about 0.93% of the atmosphere is argon[1], making it the third-most abundant gas after N2 and O2. As I understand it, most of it is produced by the ...
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How can scientists be confident of isotope ratios in past eras and varied locations, used for radiometric dating?

Radiometric dating relies on past isotope ratio predictions being very reliable. However, this is not necessarily so. For example, in Uranium forensics, 235U and 238U ratios are about the same for ...
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If 75% of radioactive material remains, how many half-lives have elapsed?

Radioactive element A radioactively decays into material B. If 75% of A and 25% of ...