Consequently, the hybrid mafic magma would be able to mix with felsic magmas more easily, resulted in higher percentage of the hybrid mafic magma in the mixing.
The magma would hit a barrier — essentially a narrowing of the fissure — which would cause the pressure to build up until it was great enough that the magma would overcome the barrier and keep moving.
We systematically search for a condition in which the magma would not be fragmented, but the initial volatile content in the magma chamber would remain constant and unchanged.
The volatiles that exsolved from the magma would enter the water-saturated porous layer.
Thus, it was expected that degassing of a column of magma would be directly observed.
A titanic eruption that would dwarf the Mount St. Helens blast of 1980 is possible within the next century, although rumblings of ascending magma would provide a warning.
Researchers think that widespread clues such as earthquakes, increased outgassing, and ground deformation due to rising magma would precede a major eruption.
At the relatively low pressures found near Earth's surface, basaltic magma would have had a density of about 2.7 grams per cubic centimeter, the tests suggest.
