geography plate tectonics and the like

Differences between basic and acidic lava

acidic:

-high in silica content

-doesn’t flow as far as basic

-gasses become trapped causing violent eruptions

-volcano will have steep sides/cones

Basic:

-low in silica content

-tends to be runny

-flows greater distance

-gasses escape

-eruptions gentler

Intrusive landforms diagram

Sill

Dyke

Batholith

Laccolith

Dyke exposed by denudation

Caledonian facts

Example: Wicklow mountains

Cause: collision of American and European plates SW-WE trend

Age: oldest, 400 MYA

Amorican facts

Example: macgillycuddy reeks, ridge and valley landscapes of Munster.

Cause: African and Eurasian plate colliding

Age: middle, 250 MYA

Alpine

Example: the alps, didn’t affect Ireland.

Cause: African and Eurasian plates colliding

Age: newest, 30 MYA

Causes of faults

Tension, compression, shear

Types of fault

Normal fault (tension)

Reverse/thrust fault (compression)

Tear/strike-slip fault (shear)