Throughout the world, there is a sharp break between ancient rock and the sedimentary or volcanic material on top of it. This is called the “Great Unconformity.” In many places just above this break, large deposits of rock debris including very large boulders are found. It appears like a major water catastrophe planed off the existing landscape leaving the large boulders behind. This is considered by many Biblical geologists to represent the time of the initial onslaught of flood waters worldwide during Noah’s Flood.