Mount Edziza is a stratovolcano consisting of a basal shield of basaltic flows surmounted by a central vent and flanked by numerous satellite cones, ash beds and blocky lavas.
22.
Fragmental cinder and spatter material and lava flows dip at angles as high as 55?away from the central vent on the eastern and southern side of the Vulcan.
23.
A parasitic cone can also be formed from a dike or sill cutting up to the surface from the central magma chamber in an area different from the central vent.
24.
These loose rocks formed by erosion, explosive activity and hot avalanches and are deposited in a large apron at the base of the volcano that extends over away from the central vents.
25.
SMS deposits are laterally extensive and consist of a central vent mound around the area where the hydrothermal circulation exits, with a wide apron of unconsolidated sulfide silt or ooze which precipitates upon the seafloor.
26.
Based on the composition of amphibole, the amphibole crystals formed in magmas with temperatures spanning, with the central vent magmas having higher temperatures at amphibole crystallization and also showing evidence of a more complex magma system.
27.
Eruptive characteristics documented for the events of that time are described as, central vent eruption with an explosive eruption, with pyroclastic flow ( s ), lava flow ( s ), fatalities and mudflow ( s ) ( lahars ).
28.
Generally, plumes formed at volcanic vents from degassing lava contain a greater amount of S 2, producing a red " fan " deposit, or in extreme cases, large ( often reaching beyond from the central vent ) red rings.
29.
According to a geological survey before the 1815 eruption, Tambora had the shape of a typical stratovolcano, with a high symmetrical volcanic cone soaring up to 4, 300 m ( 14, 100 ft ) above the sea level, and a single central vent.
30.
A Volcanic Explosivity Index ( VEI ) : 2 rating was issued for the activity between 2 May 2009 and 20 December 2009 . The activity during this period was described as having the characteristics of central vent eruption, flank ( excentric ) vent, explosive eruption and lava flow ( s ).
