laccolith
/ˈlæk.ə.lɪθ/
noun
- A mass of igneous rock that has been forced between layers of sedimentary rock, causing the layers above to bulge upward into a dome shape.
- The dome-shaped hill is actually a laccolith exposed by erosion over millions of years.
- Geologists studied the laccolith to understand ancient volcanic activity.
- The mountain range was formed by a massive laccolith pushing up the earth's crust.