Lavas are distinguished by their acidity:
- Acidic, which have a high silica content, are viscous, flow slowly (a few centimeters per hour), and solidify rapidly. Due to their relatively rapid solidification, they cause crater plugging, leading to violent eruptions.
- Basic, which, due to their lower silica content, have a higher temperature (over 1,100°C), lower viscosity and are more mobile, so they flow faster and their spouts are quiet. With the right gradient, they can reach speeds of up to 50 km/h.
- Intermediate, representing values between acidic and basic lava.
