the great falls of paterson flows over what type of rock
Great Falls (Passaic River) Geologically, the falls were formed at the end of the last ice age approximately 13,000 years ago. Formerly the Passaic had followed a shorter course through the Watchung Mountains near present-day Summit. As the glacier receded, the river's previous course was blocked by a newly formed moraine. A large lake, called Glacial Lake Passaic, formed behind the Watchungs. As the ice receded, the river found a new circuitous route around the north end of the Watchungs, carving the spectacular falls through the underlying basalt, which was formed approximately 200 million years ago.
Niagara Falls Located on the Niagara River, which drains Lake Erie into Lake Ontario, the combined falls form the highest flow rate of any waterfall in North America that has a vertical drop of more than 165 feet (50 m). During peak daytime tourist hours, more than six million cubic feet (168,000 m3) of water goes over the crest of the falls every minute.[2] Horseshoe Falls is the most powerful waterfall in North America, as measured by flow rate.[3]