When did the mountain building period that created the Taconic unconformity end?
Taconic unconformity: The Taconic unconformity is a major unconformity created during the Taconic orogeny, exposed from eastern New York State to the Gaspe peninsula. Taconic orogeny: The Taconic orogeny was a mountain building period that ended 440 million years ago and affected most of modern-day New England.
i don't know