The 1160 m spillway of the Bogus Rim lava dam.

The 1160 m elevation is a plausible call for the 1.8 Ma Bogus Rim lava
dam on the Owyhee River, OR. Consider these points:

1. It does not generate a lake that laps on to western margin of the
subaerial part of the Bogus Rim lava flow upstream.

2. It coincides with the downstream edge of the upstream-most couplet
of Bogus Rim lava remnants on both sides of the gorge below Iron
Point.

3. It is the elevation of the first unequivocal gravel outcrop on the
surface of the Bogus Rim lava flow in the gorge.

Issue: The highest pea gravel clast(s) I can find on the outer edge of
the Bogus Rim flow occur at 1205 m. An exceedingly sparse array of pea
gravel admittedly, but pea gravel nonetheless.

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More on the recent landslide in Italy. (2 additional minutes)

Fa-freaking-nomenal

Familiar Places?

I was checking out the coverage in Google Street View the other day and happened upon these.

Continuing concerns about the landslide dam at Attabad in Hunza, Pakistan

Note: This is from Dave's Landslide Blog.

Continuing concerns about the landslide dam at Attabad in Hunza, Pakistan: "The Pamir Times continues to provide excellent coverage of the state of the landslide dam at Attabad in Hunza, N. Pakistan (see earlier posts here, here, here and here). First, they have posted another remarkable image of the landslide in action:

Second they have provided various reports on the state of the efforts to mitigate the rising water level and to reopen the highway. It is clear that the road remains blocked, which must be creating incredible hardship in the valley upstream of the slide. It appears that the Chinese engineers who are planning to reopen the road have only just arrived on site. Promisingly, the report states that another group of Chinese engineers have arrived to attempt to drain the lake, presumably working with the Pakistan Army. One can only hope that these are the same group that performed extraordinary Tangjiashan barrier lake drainage operation.

The magnitude of the task is well-illustrated by this report, also from the Pamir Times. The lake is now 8.9 metres long and is filling at a rate of about 3.6 feet (1.1 metres) per day. The Pakistan Army has promised to release the water within 45 days. The images show the nature of the problem even more clearly. This image, taken from a helicopter, shows the landslide dam deposit:

It is clear that the the lake is now rising quite rapidly towards the natural spillway. This image shows the size of the lake itself:

It is clear that the water is now starting to encroach onto farmland in a serious way. Finally, this image shows the state of the lake on the ground:

"

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Owyhee River LiDAR drape on low-res Google Earth images

Ok. So Google is apparently never going to upload the high-res NAIP
imagery of the Owyhee River study area. Here is a work-around. Draping
the LiDAR on the bad imagery. Looks pretty damn good. Now we are very
proficient at doing this. On our way to developing some more elaborate
geologic projects in Google Earth. Should probably start with adding the hi-res imagery ourselves....

Thanks to Heather...she made it to the LiDAR class in San Diego last week!

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Lyell was a closeted catastrophist?

A recent (re?)-discovery by fellow Yeehow JEO:

Not so fresh geofroth, but insightful nevertheless:

Our historical figure states thusly...

"The power which running water may exert, in the lapse of ages, in widening and deepening a valley, does not so much depend on the volume and velocity of the stream usually flowing in it, as on the number and magnitude of the obstructions which have, at different periods, opposed its free passage."

which follows upon...

"It is evident, therefore, that when we are speculating on the excavating force which running water may have exerted in a particular valley, the most important question is not the volume of the existing stream, nor the present levels of the river-channel, nor the size of the gravel, but the probability of a a succession of floods, at some period since the time when some of the land in question may have been first elevated..."

Who is our extrafluvial catastrophist?

None other than Charles Lyell!

Lyell, C., 1830, The Principles of Geology, vol. i. John Murray, London.
The first quote is from page 192, and refers directly to floods resulting from breached obstructions as key to forming valleys. The second quote is from page 188.

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Short clip of the Owyhee fly-over...

Worth a look. Gives a good impression of what the flight was like. Certainly quicker than a raft.

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Slide Show from Today's Owyhee Fly-over

As promised, here are the pictures. If you would rather seem them on the Picasa site, you can go there with this link:

http://picasaweb.google.com/drjerque/OwyheeFlyOver?feat=directlink

Once there, choose view on map, or grab the kml link for a better overall experience. Note however, that the geotagging is locally off...I wasn't totally prepared to deal with a tracklog derived from a trip in a vehicle that was usually moving more than 150 mph or so. In that case, the clocks need to be tightly calibrated (to the second) and the track precision needs to be high. I will manually fix the egregious ones using the new and nifty interactive geotagging interface in Picasa.

An amazing day in the field...

Today, I had the opportunity to fly over our field area in a spiffy little experimental aircraft with my UNR colleague, Greg Arehart. Greg built the plane and is an accomplished pilot. It was an excellent time. From Reno, it takes less than two hours to reach the Owyhee in his plane. Once there, we followed an improvised flight plan driven largely by my whims and Greg's skills at maneuvering an aircraft. The map below shows the path:

It was mind-bending to be able to see the field area from this vantage. I took around 200 photos from the cockpit. Below is a very nice example. Note that it was a beautiful day to be in the field.

Best of all is the underwing camera that Greg installed on the plane. It is controlled by a laptop computer in the cockpit and takes absolutely amazing vertical air photos with overlap adequate for stereo viewing. The image below should suffice to prove that. I took 190 of these photos.

All of the photos will be posted or otherwise made available soon!

Will be visiting the field area tomorrow...in a plane!

Tomorrow I get a chance to fly over the field area in a small plane
fitted with an underwing camera. This was part of the deal that got me
to agree to teach field camp this last summer...and it is finally
coming through. Greg Arehart, my UNR colleague, has offered to fly me
over the area and snap many, many photos with his spiffy camera. These
will be ideal for creating large scale stereopairs of key areas
(failed blockages, landslide dams, etc) and also many great oblique
shots.

Below are some photos Greg took while flying over the field camp site in June.

See the full gallery on posterous

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Flash Earth and Geohacks...Who knew? Not me.

Just happened upon a sweet and simple geobrowser called Flash Earth...very smooth and easy to understand. Added bonus for me is that it links to high-res images of my favorite field area that are available only in Yahoo and Bing Maps:

Seems my pals at Google still just don't care about SE Oregon. Anyway, I found the site by perusing the details in an exif header in one of my geotagged photos. Was checking that out in Irfan View, a program I was aware of but hadn't tried yet. Turns out, it is well worth a look:

Which led me to the GeoHack wiki:

The internets are amazing, no? Totally cool.

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