Suggested causes for these include slumping, earth tremors and fault-movements, trapped water or gases and volcanic bomb impacts.
12.
Klein and Vieira proposed the site to be an extinct volcano with a volcanic cone, volcanic crater, and volcanic bomb.
13.
In addition to aa lava flows, there have been pyroclastic eruptions of ash and volcanic bombs that formed the various cones.
14.
This fragmental material was interrupted by explosions of steam, water, ash, rock, and volcanic bombs called phreatic eruptions.
15.
Large modern eruptions send volcanic bombs ( i . e . large rocks ) up to 500 m or so above the volcano.
16.
A pyroclastic particle greater than 64 mm in diameter is known as a volcanic bomb when molten, or a volcanic block when solid.
17.
Volcanic bombs are extrusive igneous rocks ranging from the size of books to small cars, that are explosively ejected from stratovolcanoes during their climactic eruptive phases.
18.
Blocks also occur due to the impact and breakage of volcanic bombs ( a bomb is a block with streamlined appearance, often expelled in a molten state ).
19.
The large masses are called " volcanic bombs "; they have mostly a rounded, elliptical or pear-shaped form owing to rotation in the air before they solidified.
20.
Initial Vulcanian activity is characterized by a series of short-lived explosions, lasting a few minutes to a few hours and typified by the ejection of volcanic bombs and blocks.
