chlorine-36

isotope

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June 24, 2026

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Chlorine-36 (³⁶Cl) is a radioactive isotope of chlorine. Natural chlorine is a mixture of two stable isotopes: chlorine-35 and chlorine-37. Chlorine-36 is produced by cosmic rays interacting with the atmosphere and is deposited in rain and snow, allowing scientists to track water migration.12

Nuclear bomb tests have also introduced significant amounts of chlorine-36 into the atmosphere, creating a tracer with a defined origin point that can be used to study water movement in soils and aquifers. This isotope, along with others like beryllium-10, has been studied using accelerator mass spectrometry, a technique that allows for more precise dating and analysis of smaller samples.2

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…source of beryllium-10, carbon-14, and chlorine-36, which are deposited in rain and snow, whence their migration may be followed. A question concerning the origin of the lavas of island-arc volcanoes, which had been disputed since the general acceptance of the plate tectonic theory of the Earth’s structure, was settled from…
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…source of beryllium-10, carbon-14, and chlorine-36, which are deposited in rain and snow, whence their migration may be followed. A question concerning the origin of the lavas of island-arc volcanoes, which had been disputed since the general acceptance of the plate tectonic theory of the Earth’s structure, was settled from…
Read More