One nit, pangea wasn’t the first supercontinent, we know of at least two, maybe three before it. The stone of the Adirondak mountains was formed as part of the Grenville mountains, which were built by a suprecontinent 1.5 billion years ago (the adirondaks got tall be’ause of a much more recent, unrelated thing, but their stone is very old). The Grenville runs from Hudson Bay to Texas