The Hummocks of Table Mountain

[AlanLichty]

On Friday I wandered up the Gorge and did a little exploring around the debris fields of the Bridge of the Gods landslide. The scale of the slide is hard to judge until you are in the middle of it with a view of the hummocks. None of the soils in the whole area below the exposed mountain face are consolidated at all. I drove up to a gravel pit operation that is just visible in the upper right which gave me a good view of a deep profile in the debris deposits. It was notable that the whole vertical profile exposed by the aggregate mining operation shows that the hummocks consist of fairly uniform deposits. I am not a big fan of gravel mines but I have to admit that this is the perfect place for extraction since the entire slope I was on is almost perfect material to drop into the sorting machines used for aggregate products and appears to be hundreds of feet deep.

This is an area that is best photographed from the air as there are few places at ground level that offer up good views of the overall terrain. One downside for flying however is that this is a very exposed hillside where winds can get rather high and I had to terminate my explorations due to strong winds. I have flown with wind in the past but not to the point where I was getting high wind warning notices on my console. The foreground lake has no name and is small compared to the many larger ones just east of where I was on Friday. More from that area next trip.

C&C always welcome.

 

[Ben Egbert]

Neat image and thanks for the geology lesson.

 

[AlanLichty]

Neat image and thanks for the geology lesson.

Thanks Ben - for me the Gorge is one giant geology lesson and a fun one at that

 

[Nilo Photography]

Beautiful image. The lake is inviting.

 

[AlanLichty]

Beautiful image. The lake is inviting.

Thanks Lenny - I believe that the little lake dries up by fall and then refills during the rainy season. It might not be quite so inviting after a couple more weeks of summer temperatures.

 

[Jameel Hyder]

Neat view from the top. Is there a trail leading to it?

 

[AlanLichty]

Neat view from the top. Is there a trail leading to it?

Thanks Jameel - the Pacific Crest Trail comes down just to the left of Table Mountain as seen above and then down to the base to cross the Columbia at the modern Bridge of the Gods in Cascade Locks. There are roads that go up closer to Table Mountain on the east flanks of the slide area which will be my next venture up there but not until this next week's heat wave passes by. That area will be an oven next week.

 

[Douglas Sherman]

Isn't geology great, Alan? You can see the scarps of the debris flow along the ridge in the distance.

 

[Kurt Harrigan]

Interesting. Did the entire mountain in the distance give way in this event?

 

[AlanLichty]

Isn't geology great, Alan? You can see the scarps of the debris flow along the ridge in the distance.

Thanks Doug - the Gorge is full of fun stuff to explore and research. Among recent geological events in the Gorge this is one of the most recent.

Interesting. Did the entire mountain in the distance give way in this event?

Thanks Kurt - yes - the whole mountainside came down and it slid all the way down to create a temporary dam on the Columbia River. The slide was known as the Bridge of the Gods since it allowed indigenous tribes to cross the Columbia while the dam held. There have actually been several earlier slides in the same area.

 

[JimFox]

This is really cool looking Alan!

 

[AlanLichty]

This is really cool looking Alan!

Thanks Jim - I have some ideas on how to get a better view of this area once things cool down (and maybe a cloud or two?) up here.