They are composed of a kind of igneous rock not found anywhere near Wiltshire.
I did not see any eruption of igneous rock on any part of the day's journey.
The Flume, on Star Island, is a fine specimen of the intrusion of igneous rock among the harder formation.
What relation do they occasionally bear to sheets of igneous rock?
Several pieces of shale lay exposed under a fold of igneous rock.
How may granite be at one and the same time a metamorphic and igneous rock?
The rocks are late Paleozoic strata, pierced by a large body of igneous rock.
The beacons were found to be part of a horizontal, stratified series of sandstones underlying the igneous rock.
Evil is a state of imperfection running through every vein of nature, from the igneous rock to the brain of man.
For instance, an igneous rock may become a schist without going through the intermediate stage of sedimentation.