Geology in Action

Last time we walked down to the Canyon Lakeshore on our family's property, you couldn't hike very far up the little gully that feeds down into our swimming cove. It was just too overgrown. So this was quite a surprise:

Of course, some of the openness is due to the deciduous trees being bare, but that doesn't account for all the change. During one of the heavy rains we had at the end of the year, a whole lot of stuff must have washed down this gully, obliterating a lot of brush and leaving practically a road-like surface extending a good many yards upstream.

I tried to find an older picture so that the contrast could be more easily shown, and wasn't too successful. But I did find this photo taken from a little ways up the draw, in February of 2012:

I can't say for sure, but I think this photo taken last week shows something of the same scene, but from further away from the cove:

Even if the topography changes aren't apparent, all that gravel certainly looks new!

We speculated that increased construction uphill from our property provided more than usual loose stuff to wash down toward the lake.

Not all of the geological debris was left on the shore, either. You can see a large tongue of deposited rocks and dirt extending pretty far out into the cove in this shot:

And not all of this new lake bottom had to have come from far away, either. Here's a closeup of where the gully empties into the cove; note the deep and rather recent-looking erosion of the gully's banks:

The eroded material has to go somewhere, doesn't it?!

Our little cove is actually a great barometer displaying the cyclic changes affecting lake as well as events like this recent erosion/deposition occurrence. Compare this shot of it from our latest trip, when the Lake was pretty much at normal pool elevation...

...to these shots from April of this year...

...and from February 2012...

The last two photos show the place during two different droughts. 

But in this part of the country we're always, it seems, either in a drought or suffering from floods. There's even more dramatic evidence nearby of the geological changes that floods can bring. Someday, we will take one of the tours of Canyon Lake Gorge, an impressive new channel cut when the Lake overflowed during the floods of 2002. Since I've made doing this—finally—a new year's resolution for 2016, I hope I'll be able to show and tell you about this amazing feature before too long.