The Watering Hole: September 17 — Fun with basalt

Photo by Zach Meier

From the Wiki:

The Columbia River Basalt Group is a large igneous province that lies across parts of the U.S. states of WashingtonOregon, and Idaho.

During late Miocene and early Pliocene epochs, one of the largest flood basalts ever to appear on the Earth’s surface engulfed about 163,700 km² (63,000 mile²) of the Pacific Northwest, forming a large igneous province with an estimated volume of 174,300 km³. Eruptions were most vigorous from 17–14 million years ago, when over 99% of the basalt was released. Less extensive eruptions continued from 14–6 million years ago.

Erosion resulting from the Missoula Floods has extensively exposed these lava flows, laying bare many layers of the basalt flows at Wallula Gap, the lower Palouse River, the Columbia River Gorgeand throughout the Channeled Scablands.

I just love our geology.  🙂

This is our daily open thread — rock on!