Vulkanske bomber er halvtflytende lava-fragmenter som slynges ut fra krateret under
et utbrudd. De kan være fra 10 - 64 mm i diameter, og kan ha et meget varierende
utseende på grunn av at de formes når de størkner under sin reise gjennom luften.
. Forskjellen mellom blokker og bomber er at bomben slynges ut i luften i
halvtflytende form mens blokkene er faste fragmenter.


Tephra is the general term now used by volcanologists for airborne volcanic ejecta of
any size. Historically, however, various terms have been used to describe ejecta of
different sizes. ... Fragments larger than about 2.5 inches are called blocks if they were
ejected in a solid state and volcanic bombs if ejected in semi-solid, or plastic, condition
. ... Volcanic bombs undergo widely varying degrees of aerodynamic shaping,
depending on their fluidity, during the flight through the atmosphere. Based on their
shapes after they hit the ground, bombs are variously described, in graphic terms, as
"spindle or fusiform,", "ribbon", "bread-crust", or "cow-dung".
(Tilling, Heliker, and Wright, 1987)