An erupting stratovolcano poses numerous hazards for nearby habitation, but none nearly so terrifying and deadly as the pyroclastic flow
. Pyroclastic flows
, comprised of tons of superheated sulfuric gases, particulate rock materials and ash, can reach temperatures of 1,830 °F and travel at alarming speeds up to 450mph. Convection of materials within the clouds causes them to become a suspension, fluidizing
noxiously across the surrounding landscape for miles, in some cases even uphill or across open water. Wherever these clouds come in contact with humans the result is catastrophe, as the residents of Herculaneum
and St. Pierre
, Martinique learned within minutes of the eruptions of Vesuvius in 79AD and Pelee in 1902-- both towns were overwhelmed by pyroclastic clouds, igniting all flammable materials and incinerating and suffocating the inhabitants. None survived Herculaneum
, while just two of St. Pierre's
26,000 survived, one of whom was a prisoner condemned to death and awaiting his execution in a dungeon cell. Despite their incredible capacity for violence, pyroclastic flows are also capable of producing mesmerizing
, awe-inspiring beauty
posted by baphomet
on Feb 18, 2009 -
Iran considers moving capital away from Tehran.
Tehran lies on a major seismological fault and experts have long warned that a strong earthquake in the city would be devastating. A professor of geophysics at Tehran university, has warned that if a quake of similar magnitude hit Tehran it would kill more than 700,000 people. Government buildings would be destroyed.
posted by hoder
on Jan 5, 2004 -
About 250 million years ago all of the continents were joined in a single land mass called Pangea
. Then they broke up and drifted apart
to their present positions. Plate tectonic projections forecast that 250 million years from now, the continents will once again join up into a single land mass now dubbed Pangea Ultima
. JRR Tolkien couldn't have dreamt up a better Middle Earth.
posted by lagado
on Dec 7, 2000 -