Zusammenfassung der Ressource
Volcanology
- Magma
- Types of magma
- Basaltic
- From oceanic plate
- Andesetic
- Rhyolitic
- Ways to generate magma
- Decompression melting
- Pressure
- Flux melting
- Addition of
water
- Lowers temperature
- Transfer of heat
- Components of Volcanic Eruption
- Lava flow
- Andesitic and rhyolitic lava flows
- Siliceous lava flows
- Thick stubby flows that
does not move far from
the vent
- Basaltic Lava
- Pahoehoe flow
Anmerkungen:
- As basaltic lava flow are exposed to
the atmosphere and cools, it
advances as a series of small lobes
and toes that cotinually break out from
a cooled crust
- Bizarre shapes
- Aa flow
Anmerkungen:
- Higher viscous basaltic and
andesitic lava, while cooling
forms a rough surface
composed of broken lava
blocks. The surface may cool,
but the interior remains
molten and continue to
advance.
- Jumbled mass of
angular blocks
- Pillow lava flow
Anmerkungen:
- Surface of basaltic lava cool
quickly under water, while the
inside is still molten. The
surface cracks and the molten
magma oozes out. The process
continues resulting in piles of
lava pillow stacked above
one another
- Elongated,
interconnected flow
lobes that are circular in
cross section
- Gases
Anmerkungen:
- Super dangerous! Can kill organisms by direct ingestion or by absorption onto plants followed by ingestions by organisms
- Carbon
dioxide, chlorine, sulfur
and fluorine gases
- Pyroclastic materials
Anmerkungen:
- Explosive bursting of bubbles will fragment the magma into clots of liquid that cool as they fall through the air
- Ash and dust
- Volcanic bombs and lapilli
Anmerkungen:
- Lava fragments that were ejected, consist mostly of gas bubbles
- Tephra fall
Anmerkungen:
- Clouds of gas and tephra that rise above a volcano produce an eruption column that can rise up to 45km , picked up by the wind, and eventually fall to the surface after being carried for some distance
- Volcanic block
Anmerkungen:
- Solic rock fragment greater than 64mm in diameter that was ejected from a volcano. Consist of solidified pieces of old lava flows from a volcano's cone
- Pyroclastic flow
- Types of volcanoes
- Shield Volcanoes
Anmerkungen:
- Formed by non-explosive low viscosity basaltic magma
- Gentle upper
slopes, steeper
lower slopes
- Thin lava flows built
up over a central vent
- Stratovolcanoes
Anmerkungen:
- Steep upper slopes, gentle lower slopes
- Found along divergent plate
boundaries, subduction zone and
hotspots