Chemical processes on the planetary surface

Chemical weathering of primary rocks on the surface of Venus is evidenced by a number of indirect arguments. Thermodynamic calculations show that the measured concentrations of chemically active atmospheric gases are high enough for the following chemical alteration processes of primary minerals of mafic and ultramafic igneous rocks to proceed: carbonization, oxidation, hydration(?), formation of sulfates, sulfides, and F- and Cl-bearing minerals. The rock-forming minerals of acidic rocks are stable on the surface. The highlands are considered a planetary terrain of maximum favorable conditions for chemical weathering. Aeolian abrasion at the micro- and megascopic scale at the highlands is a possible geological agent affecting the chemical interaction of rocks with atmospheric gases. If global chemical equilibrium does exist in the atmosphere-surface rock system, weathering should be widely distributed on the surface of Venus. -from Authors