Dana walks over to investigate the basalt berm and overlying terrace deposits, on the other side of the sandy inlet. Even though there's no sky visible in this photo, the most striking thing visible to me is weather/climate related. It's tough to say what a lot of the shrubs on the terrace deposits are, but some of them-definitely those in the upper right corner- are shore pines. Look at how coastal winds have whipped and shaped them. Winter winds can be fierce on the Oregon coast, often over hurricane force, sometimes well over 100 mph (160 kph).
Hopefully I'll get a few shots in ten days or so of an excellent bio-geo-meteoro interaction near Humbug Mountain, on the southern coast. Dana's coming into town May 6, and I'm pondering whether to schedule this series for that week, or try to keep up on the fly. Both have upsides and downsides. We'll see.
A fun thing to do at the beach during low tide is to look at the short-lived erosional features. Many fluvial landforms can be found, at small scales, changing and evolving over periods of minutes in ways that would take real stream systems years to centuries. In this case, we're seeing sheet wash on the upper "plateau" channeled into a series of distributary "canyons" in response to the rapid drop in base level as the tide went out.
Of course, there's plenty of water percolating through the sand as well. Under the sheet wash, the water table is right at the surface, and that level drops to the left. But the main stream has cut below the water table, so "springs" have formed along the base of the "plateau's" "escarpment." With that former groundwater back on the surface, it can again erode the sand grains in that area, creating an apron similar to a bajada between the main stream and the escarpment.
Water running off the tidepool platform combines with water from a small stream and more seeping out of the hillside to carve a moat around the rock. This area is not as heavily colonized by sea life; it's frequently buried in sand. They can survive a little of that, for short period of time, but burial will eventually kill them off.
Mussels along the top and right, barnacles on the left, a sea star in the upper right middle, and hooman beans top and bottom. Geology not so much (basalt), but I really like this photo. Dana told me later this was the first time she'd seen a starfish in it's native habitat (we saw a LOT of them). I was a little surprised at the time, but I've realized since she just hasn't spent that much time at rocky coastlines. Most of her coastal visits have been unconsolidated sediments.
There is a spouting horn here, but I'm not certain this is actually it. A true spouting horn consists of a sea cave with a hole in its roof toward the end. Waves funnel into the cave and then burst through the hole, creating a geyser-like feature, but timed to the wave period. I'm not certain the feature we're seeing here is actually a cave rather than just a blind alley that's causing the waves to splash up at its end. The true spouting horn here is at the southern end of the trail system, below and seaward of a high bridge.
I didn't notice it until I'd assembled the gif, but in two sequential frames of this animation, you can see a human silhouette walking in front of the plume. Person for scale!
Photo unmodified. September 21, 2010. FlashEarth Location. (This is the viewing platform for the actual horn; I'm not sure where I was standing nor where I was looking in the above photo. Also, we were here intentionally at low tide; the horn is more spectacular at high tide. Unless you spend a whole day here- and there's certainly enough to justify that- you either get tidepools, or waves crashing at their most vigorous.)