Around 350 million years ago, a great delta had been created from a river that moved sediments from the northeastern part of Illinois to the southwest. On this delta, great forests grew. This forest would later become a major fuel source - COAL!
Around 350 million years ago, a great delta had been created from a river that moved sediments from the northeastern part of Illinois to the southwest. On this delta, great forests grew. This forest would later become a major fuel source - COAL!
