- Geology and coal resources of the Centralia-Chehalis district, Washington (pubs.usgs.gov)
The Centralia-Chehalis coal district includes about 570 square miles in south western Thurston County and northwestern Lewis County, Wash., midway between Seattle, Wash., and Portland, Oreg., and forms a part of the subbituminous and lignite coal fields of southwestern Washington. It adjoins the Morton coal field on the east and the Toledo coal field on the south. It includes a part of the extreme western foothills of the Cascade Range and a part of the eastern border of the Coast Ranges.
northbound on Interstate 5
- Juan de Fuca Plate (Wikipedia)
The Juan de Fuca Plate is a small tectonic plate (microplate) generated from the Juan de Fuca Ridge that is subducting beneath the northerly portion of the western side of the North American Plate at the Cascadia subduction zone. It is named after the explorer of the same name. One of the smallest of Earth’s tectonic plates, the Juan de Fuca Plate is a remnant part of the once-vast Farallon Plate, which is now largely subducted underneath the North American Plate.
southbound on Interstate 5
- Lewis County, Washington (Wikipedia)
Lewis County is a county in the U.S. state of Washington. As of the 2020 census, the county’s population was 82,149. The county seat is Chehalis, and its largest city is Centralia. Lewis County comprises the Centralia, WA Micropolitan Statistical Area, which is also included in the Seattle-Tacoma, WA Combined Statistical Area.