Laccoliths Flashcards
What is an example of a Laccolith?
Big bend national park, Texas
How do laccoliths form?
Magma intrusion
What does the process begin with? *
Process begins with the intrusion of magma into subsurface area of the Earth’s crust
What happens next?
Magma starts to spread laterally within the crust
What happens as it intrudes?
As it intrudes, the magma seeks paths of least resistance along fractures or weaker zones in the rock. As it intrudes it’s upward force causes the overlying layers to uplift and bulge making a dome
What happens to magma then?
Magma within the laccolith will cool and solidify
What acts on the region?
Erosion and uplift act on the region and overlying rock layers are gradually eroded, exposing the laccolith at the Earth’s surface
What is a batholith?
Batholith- a cooled magma chamber which has been exposed by erosion
What are sills?
Sills are cooled down magma which has intruded between two overlying layers
