Results of thermal gas release from copper, silver, and gold targets bombarded with krypton and xenon ions of energies between 20 and 450 keV will be presented. The influence of bombardment doses is shown. The desorption carried out under high-vacuum conditions was examined with the tracer technique, and the fractional release was determined as a function of temperature, energy, and dose. Depth distributions were studied using a corrosion film technique, and the correlation between such distributions and the gas release was investigated. The results are compared with earlier work, and an attempt to elucidate inert-gas diffusion in copper is described.