As the earth formed, naturally occurring radioactive material

Naturally Occurring Radioactive Materials  (also known as NORM) are a wide range of radioactive isotopes that include elements such as carbon 14 and potassium 40, both of which are in the human body. But the main radioactive elements involved in oil and gas production are those found throughout Earth's crust. These elements include uranium and thorium and their respective byproducts, including radon gas.

 EnhancedNaturally Occurring Radioactive Materials (TENORM) consist of materials, usually industrial wastes or by-products enriched 

Spontaneity tell us the direction of the reaction, but not how fast it goes. gibbs free energy brings together enthalpy, entropy and temperature in one easy formula. g = h - ts. and, finally the sign of delta g is always negative for a spontaneous reaction.