Geology Reference
In-Depth Information
SHALLOW-LEVEL INTRUSIONS
Collapse Caldera
Dyke fed
fissure
Cone
Plug
Diatreme
at surface
Volcano
Saucer
shape sill
Vent
Shallow
chambers
Laccolith
Nested
sills
Dyke
Sill
Figure 6.1
Schematic diagram of magma plumbing systems beneath volcanoes.
Intricate networks of dykes and sills make their way from depth to the surface.
Shallow chambers form laccoliths beneath volcanoes where magmas can mix
and be recycled. A variety of small plugs, sheets and vent facies occur very near
the surface.
