One difference between wide & narrow craters is the presence of this to mix with magma & cause big steam explosions
Finally, there are some major physical differences between volcanism on the 
Earth and on... [DOC] [TLE] Soda Bottle Volcano - Mount Rainier National Park (U.S. National ... [PAR] Puffs of steam break out between the pot and lid in the same way that volcanic ... 
During an explosive volcanic eruption, gases escape into the atmosphere; 
however, ...