Uranium disequilibrium dating laboratories
Contact: Jim Paces The USGS Denver Radiogenic Isotope Laboratory (DRIL) located in Building 21 of the Denver Federal Center obtains geochemical and isotope data from rock and water samples for characterization studies.
This document describes standard procedures for the collection of uranium (U) and thorium (Th) isotope data.
deferrment while consolidating - Uranium disequilibrium dating laboratories
Uranium-thorium dating, also called thorium-230 dating, uranium-series disequilibrium dating or uranium-series dating, is a radiometric dating technique commonly used to determine the age of calcium carbonate materials such as speleothem or coral.
Unlike other commonly used radiometric dating techniques such as rubidium-strontium or uranium-lead dating, the uranium-thorium technique does not measure accumulation of a stable end-member decay product.
The U-series disequilibrium method is based on the radioactive decay of radionuclides within the naturally occurring decay chains.
There are three such decay chains, each starts with an actinide nuclide (i.e., 238U, 235U, and 232Th) having a long half live (all have T1/2 The MC-ICPMS U-series laboratory focuses on development and application of U-series dating techniques to address fundamental research in areas such as palaeoclimatology, palaeoceanography or archaeology and human evolution.
Uranium-thorium dating has an upper age limit of somewhat over 500,000 years, defined by the half-life of thorium-230, the precision with which we can measure the thorium-230/uranium-234 ratio in a sample, and the accuracy to which we know the half-lives of thorium-230 and uranium-234.