Did you know that Sussex County is home to a volcano?
Rutan Hill, also known as Volcanic Hill, is located in the Beemerville section of Wantage Township. The volcano has been inactive for 440 million years, and now disappears into the landscape of beautiful Sussex County.
The site is well-regarded by geologists due to the presence of a rare type of igneous rock called nepheline syenite which can be found at the site.
…in northern Sussex County 11/2 miles west of Libertyville, a circular hill of trap rock, a quarter of a mile in diameter, in which are included many fragments of granite, slate and limestone, presents some characteristics of a volcanic plug, the trap rock with the included fragments representing the lava which solidified deep in the throat of the volcanic cone, which may once have marked this site. This vent, is however, so far removed from the great lava flows of the Newark series, and is so small in comparison with them, that it can hardly be regarded as their source. The fissure or throat of which these floods of lava came more probably lies beneath the parts of the sheets not yet exposed to view. -“The Geology of New Jersey,” December 1940