Radioactivity in the continental crust (due mainly to the isotopes ²³⁸U,²³⁵U, ²³²Th and ⁴⁰K), as a energysource for chemical evolution in the early Archean (between 3.5 and 4 Ga bp), is reviewed.The most important radioactive sourcein the continental crust is due to theproduction and accumulation of radioactivegases within the crust voids (porosity). Thestudy of such mechanism has allowed us toreach a deeper understanding about the nature of the radioactive source and to describe itsbehavior, particularly with regard to prebiotic chemical evolution. An effectivetotal energy of 3 × 10^{18 Ja -1} hasbeen obtained for a depth of 1 km, 4 Ga ago. If a depth of 30 km is taken, the obtained valueis almost equal to the UV solar energyradiation (<150 nm).="" within="" thevoids="" the="" radioactive="" source="" of="" thecontinental="" crust="" played="" a="" relevant="" role="" inprebiotic="" synthesis.="" in="" uraniumdeposits="" of="" the="" same="" age,="" the="" role="" ofradiactivity="" must="" have="" been="" even="" more="" relevantin="" favoring="" chemical="">