700,000 year old basalt lava flow
![Undine Falls along Lava Creek spills over a 700,000 year old basalt...](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/full_width/public/vhp_img17.jpg?itok=7bNWyGKN)
Detailed Description
Lava Creek spills over the surface of a basalt lava flow that was emplaced about 700,000 years ago. Named after the falls, the Undine Falls Basalt erupted before Yellowstone's third caldera-forming explosive eruption that ejected the Lava Creek Tuff (named after Lava Creek) about 640,000 years ago. Scientists first distinguished the Lava Creek Tuff from the Huckleberry Tuff about 3 km downstream from the falls in the 1960s. This was the first clue that Yellowstone's history included more than one caldera-forming eruption.
Sources/Usage
Public Domain.