镭-234 (Radium-234) is a radioactive isotope of the element 镭 (Radium). It is part of the decay series of 铀-238 (Uranium-238) and is produced when 铀-238 decays into 镭-226 (Radium-226). Radium-234 has a half-life of about 24.1 days, meaning it takes this amount of time for half of a sample to decay into other elements. Due to its radioactivity, 镭-234 is of interest in various fields, including 地质学 (Geology) and 放射性同位素 (Radioisotope) studies. It can be used to date geological formations and understand the processes of radioactive decay in nature.