Grand Falls formed in the Late Pleistocene when lava flows from Merriam Crater dammed the Little Colorado River. The Little Colorado River is an ephemeral stream with flow occurring during spring melt in the White Mountains and during northern Arizona's summer monsoon. Grand Falls is higher than the much more famous Niagara Falls on the US-Canada frontier.
Photographer: Dale Nations
Photo Date: circa 1985
Photo Location Accuracy: Known Location
Photo Tags: Grand Falls, Merriam Crater, basalt, ephemeral stream, geotourism, flood, monsoon, Pleistocene