Gas leaks — the release of gases (mostly H 2 O, CO 2 , and SO 2 ) from the magma into the atmosphere through cracks in the overlying rock Bit of a bulge — the deformation of part of the volcano, indic...Gas leaks — the release of gases (mostly H 2 O, CO 2 , and SO 2 ) from the magma into the atmosphere through cracks in the overlying rock Bit of a bulge — the deformation of part of the volcano, indicating that a magma chamber at depth is swelling or becoming more pressurized The quakes may be the result of the magma forcing the surrounding rocks to crack, or a harmonic vibration that is evidence of magmatic fluids moving underground.
