Question: what is the difference in silica content and viscosity between light-colored and dark-colored magma?
Answer: The amount of silica in magma helps to determine its viscosity. The more silica magma contains, the higher its viscosity. Magma that is high in silica produces light-colored lava that is too sticky to flow very far; ex. ... Low-silica magma flows readily and produces dark-colored lava; ex.