Geography Glossary - Rocks and Landscapes

Batholith	A big 'dome' shaped intrusion of magma in the crust.
Clay	A fine grained sedimentary rock, it is made from the chemical weathering of other rocks and minerals.
Chalk	It's a sedimentary rock, a type of limestone made of calcium carbonate.
Doline	Hollows in the limestone formed by a stream going into it or by an underground cave collapsing.
Dry valley	Old river valleys that were formed when there was more water usually after an ice age.
Dyke	A vertical intrusion of magma in the crust.
Frost-shattering	Water freezing in cracks then expanding causing erosion.
Granite	Rock formed by magma cooling inside the crust.
Igneous rock	Comes from magma from a volcano or from magma that cooled under the Earth surface.
Impermeable	Water cannot pass through.
Intrusion	Where magma has been forced into cracks in the crust leaving a dyke, trench or batholith.
Jointed rock	Rocks that have small cracks in them.
Limestone	A sedimentary rock made from skeletons or shells of sea creatures.
Limestone Pavements	Cracks in exposed limestone are made bigger by solution.
Metamorphic rock	Rock that has been put under pressure until they change into a new type of rock.
Porous	Lets water pass through.
Quarry	Open cast mines.
Ridge	The exposed end of a dyke which sticks out at the surface of the crust.
Schist	A form from basalt or shale or has been pressurised.
Sedimentary rock	Formed by living things that have fallen to the bottom of a sea or lake.
Swallow hole	Where a stream dissolves a hole in limestone creating a hole.
Tor	The exposed part of a batholith.
Trench	A horizontal intrusion of magma in the crust.