Soils and soil gas samples were collected along three traverses across the copper-zinc ore bodies at Johnson Camp, in southeastern Arizona. The copper-zinc ore occurs as isolated sulfide and oxidized sulfide replacement bodies in limestone host rocks covered by 10--225 m of alluvium. Samples were analyzed for helium using mass spectrometry and for carbon dioxide and sulfur compounds by gas chromatography. Above average concentrations of carbon dioxide and helium in soil gases, as well as above average concentrations of carbon dioxide degassed from soils, occurred over and adjacent to all three ore bodies. Carbonyl sulfide and carbon disulfide degassed from soils occurred in the vicinity or ore bodies as deep as 150 m, but not to 225 m depth. Volatile constituents in soil gas samples collected by hollow probe defined the ore bodies better than volatile constituents degassed from surficial soil samples. |