When we think of major geological changes in the Earth we usually think of events that happen too slowly to notice. Certainly no one would notice major geological shifts in the space of one lifetime, or even the lifetime of a civilization. Yet, if the biblical history is true, major geological changes have taken place within the lifetimes of civilizations.
From 500 A.D. until their invasion by the Incas in 1476, a large and powerful civilization lived in what is now northern Peru. Between 500 and 1200 A.D. they built the largest network of irrigation canals ever constructed in South America. This canal system was built using engineering methods that are considered impressive even by modern standards. The remains of the canal system can still be seen today. However, because of geological changes, the canals no longer work. As a result, farming is possible on less than one-half of the lands used by the original Indians.
Geologists studying the canal system discovered that portions of the South American continent shifted so rapidly that the Indians had to continually redesign their canal system to keep water in it. The plates on which South America rests deep within the Earth changed the slope of the ground so rapidly that the Indians could not keep up with the changing geology.
The plight of the ancient canal-building Indians of Peru helps us understand that the forces that shaped today's Earth did not need millions of years to do their job.