One difference between wide & narrow craters is the presence of this to mix with magma & cause big steam explosions
.... 
of changing pressure and temperature causes both fragmentation of magma into
... [DOC] [TLE] How Polygenetic are Monogenetic Volcanoes: Case Studies of ... [PAR] Sep 21, 2016 ... (E) Complex Tihany volcanic center where large distances between ... Table 1.