ODE shield volcanoes and cinder cones- Exam 2

where does volcanism occur

MOR and ring of fire (hotspots), cont arc, island arc, rifts

shield volcanoes

largest diameter and height

common form at hotspots and cont rifts

broad slopes (~10) upside down warrior

where does volcanism occur

MOR and ring of fire (hotspots), cont arc, island arc, rifts

shield volcanoes

largest diameter and height

common form at hotspots and cont rifts

broad slopes (~10) upside down warrior

cinder cones

smallest diameter and height (~1000 ft high)

common on frames (sides) of other volcanoes and cont rifts

steeper slopes (~35)

mafic, pyroclastic debris

form >1 years

composite volcanoes

strato volcanoes

polymerization

linkage of silica tetranedra in magma

shield volcanoes composition

mafic lava flows from extrusive style of eruption

pahoe- hoe lava

ropy lava- thick and grey

Aa lava

thick lava- hot magma- red- some pahoe- hoe

columnar jointing

cooling fracture and cracks

cross sections- long columns of dry lava basalt

large rocks- polygons mafic

pillow basalt

underwater eruptions- magma gets into water and cools fast into globs like pillows

lava tubes

insulated paths

cave like tunnels carried lava through

lava fountains are explosive and very high up

shield volcanoes hotspots

hawaii, iceland, galapogoes

Mauna loa

hawaii shield volcano

~10 slope

mafic

small cinders

dime sized

how are volcanoes identified

shape and composition