This paper describes a methodology developed to measure the activity concentration of the four natural radium isotopes 226Ra, 228Ra, 224Ra and 223Ra in water samples, using γ-ray analysis performed with a hyperpure germanium ...

The Paraná volcanic rocks (Serra Geral Formation) are characterized by four different types of rocks. The basalts are the most common, and display an integranular texture and dark gray to black color, in massive outcrops. ...