Columbia River Basalt Group map shows main regions of basalt exposure in Washington, Oregon, Idaho and Nevada, USA. (usgs.gov)- Pasco, Washington (Wikipedia)
Pasco (/ˈpæskoʊ/ PAS-koh) is a city in, and the county seat of, Franklin County, Washington, United States. The population was 77,108 at the 2020 census, and 79,315 as of the July 1, 2022 estimate.