Figure 12. The gully in this photograph is underlain with a nearly vertical basalt dike that is about 5 feet wide. Rocks on both sides are quartzite and phyllite of the Kittery Formation. Visitors can find this exposure at the extreme southwestern corner of the coastal exposures in the park. The dike formed about 200 million years ago when the modern-day Atlantic Ocean began to open.
Last updated on October 6, 2005