钍-234 (Th-234) is a radioactive isotope of the element 钍 (thorium). It is produced through the decay of 铀-238 (uranium-238) and has a half-life of about 24.1 days. Th-234 decays into 镭-234 (radium-234) through beta decay, contributing to the natural decay series of uranium. Th-234 is of interest in nuclear science and environmental studies due to its role in the 铀-238 decay chain. It can be found in trace amounts in natural thorium ores and is used in research related to radioactive dating and the behavior of radioactive materials in the environment.