The Cascade Mountain range runs along the Washington-Oregon coast. It was formed from the Juan de Fuca oceanic plate converging with the North American Continental plate. This convergence is the cause of the volcanic activity seen here (
https://geology.com/nsta/convergent-plate-boundaries.shtml). Because of this activity, the area has been deemed the Ring of Fire, and is also an area of much earthquake activity (
https://geomaps.wr.usgs.gov/parks/province/cascade2.html). The North American Continental Plate is moving westward (compressing the plates together), causing the Juan de Fuca Oceanic Plate to subduct beneath the more buoyant continental plate. Because of this compression, it is a reverse fault and we would see folding in the deeper rock layers. According to the video, continental-oceanic convergence results in granitic rock being expelled in volcanic activity, in contrast to the basaltic expulsions we see in oceanic-oceanic convergence.
There is also sea floor spreading being caused by this plate movement, between the Pacific and Juan de Fuca plates (
https://geomaps.wr.usgs.gov/parks/province/cascade2.html).
https://geomaps.wr.usgs.gov/parks/province/cascade2.html
https://expo.oregonlive.com/life_and_culture/erry-2018/06/68531252b32020/10_natural_treasures_of_the_ca.html
https://www.seattlemet.com/articles/2018/5/22/grizzlies-might-return-to-the-cascade-mountains
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