These pieces of basalt (approximately 18 inches in length) caught my as I was exploring road cuts in the Yakima River Canyon. They seemed to be accented by an artists brush. Different patterns and different colors abounded in adjacent rocks. Since the rocks were adjacent and seem to be part of the same basalt flow, why are they so different in surface color and pattern. I need to do a little research on what factors determine the color and patterns.
A couple of miles up the road from my last post, I saw these basalt columns protruding vertically upward. They were located on a different ridge. The forces driving the uplift were different than the ones from the first ridge. I ask why, what caused the difference? Did this ridge lift at a different time or were the forces just different from the ridge in the first post. My curiosity kills me. I think I need to do more research on how these “Yakima Folds” evolved.
How did a river cut such a gorge through a basalt mountain. Maybe it didn’t. The Yakima River originates high in the Cascade Mountains. The upper end of the river was not part of the great Missoula floods that covered Eastern Washington. The Yakima meanders through several Basalt Ridges. The nature of a meandering steam is that it flows through a relatively flat plain. If the mountains were there first, the river would have flowed around them. So how did the Yakima get through the mountains. Maybe the river was there first, As the ridges slowly developed as part of the Yakima fold formations, the river could have gradually cut a channel through its original riverbed route.
I spent a day slowly driving through the Yakima River Canyon. I stopped and photographed several interesting rocks and formations. During the next week or so, I will post several of my images.