Friday, February 6, 2009

Where on (Google) Earth #158

Click Image to Enlarge

I just won my second Where on (Google) Earth, yesterday, from Dave Schumaker at Geology News - his first time to win!! - after he posted Mt. Ruapehu, New Zealand for WoGE#157. A second win, a second volcano!!

That means I get to post the #158 edition of this fine game. I think I got lucky: 1) I was online when #157 was posted, 2) for some reason I thought the place looked familiar, although I'm really not sure why, and 3) so I was convinced I could find it! I recognized it as a volcano, and so first looked in all the usual places (the Cascades, for example), and then I wondered... Dave said it was one of his favorite areas; so I looked, and sure enough, he had posted about the volcano back in 2007: I found it first on his website! I think it looked familiar because of the beige silty ash color of the mountain, or maybe it was the crater lake...

To win this game, be the first to find and the first to post the correct latitude and longitude of the above unknown area in the comments, and also describe as much of the geology of the area as you can. I'd be greatly pleased if you could name the closest mountain, which is in the center right above the tiny Image (c) 2009 TerraMetrics lettering. If you win, you get to host the next WoGE on your blog. (Non-blog winners have a chance of hosting right here!)

I am invoking the Schott Rule this time, which means that former winners have to wait exactly one hour per win before posting their answers. Former winners and former locations can be found here. Post time will be 5:00 pm Pacific Standard Time, GMT-8.


Peter L said...

58.86N 125.50W - This is the Sentinel Range in the Norhteast Muskwa Ranges of the Far Northern Rockies (northeastern British Columbia, Canada). The closest mountain in the center must be the Folded Mountains; in the south (left) the Alaska Hwy runs along the Toad River. So far so good, I found this relatively quickly. The geology is a little more unclear to me. I guess this is the thrust and fold system developed within the mid-Ordovician - mid-Devonian Macdonald carbonate platform of the Cordilleran Foreland Belt, just behind the eastern limit of the Cretaceaous-Tertiary Cordilleran deformation.

Silver Fox said...

You got it! The mountain is commonly called Folded Mountain, and it may indeed be part of the Folded Mountains, although some of the local geography is obscure to me. That's the Alaska Highway or Alcan, with Folded Mountain being at Milepost 409. And that's Toad River, which eventually flows into the Liard River.

The geology is a bit obscure. You're right, it's right at the eastern edge of K-T deformation and is part of the northern Rocky Mountain fold and thrust belt; I'm not as sure about the rock ages (limestone) or regional name of the carbonate platform - you are probably right about those, but finding details online almost seemed to require already knowing the details!! The area is part of what is sometimes called Ancestral North America, a deformed part of the miogeocline.

You can see the dip-slope of Folded Mountain dipping relatively shallowly to the southeast, and you can see a few steeper dip slopes in some of the mountains right behind Folded Mountain. At the upper part of the image, the dips steepen even more toward Muncho Lake, barely seen in the upper right. The steeper dip slopes can't really be seen from this angle.

If anyone knows more particular details about the Sentinel Range and Folded Mountain, please leave some comments. I'll probably post some photos and drawings of the area and a few links showing general geology of the region in another post.

BrianR said...

I was near there, but didn't go far enough north! Dang. Nice work Peter.

SF ... since Peter doesn't have a blog, can you post a link to his site when he puts up #159 ... just so it doesn't get lost.

Ron Schott said...

Here's the description I had put together for it (&^$!% Schott Rule!):

Folded Paleozoic strata in the Sentinel Range in Muncho Lake Provincial Park, about 6 miles northwest of Toad River, British Columbia. The Alaska Highway follows the Toad River through the glaciated valley at the left side of the image. The 6900+ foot peak in question appears to be unnamed in this online topographic map of the region. There's a viewpoint at the base of this mountain that is named Folded Mountains viewpoint, so conceivably that could be a proper name for this particular mountain or at least this subdivision of the larger Sentinel Range. (I've also seen the spelling Sentinal Range.) Lowell Laudon used to take the UW-Madison Yukon Field trip through this region on the way to Tagish Lake and he has described the geology and paleontology of this region in an AAPG Bulletin article.

Anonymous said...

I'd sure like to know how Peter figured it out! Nice work! It looked vaguely familiar, being obviously a fold and thrust belt, like near where I live, but even the Canadian Rockies cover such a vast area, I couldn't narrow it down at all.

You can download a geological map and cross-section of the area, here:

(They're huge raster files, the smallest is in MrSID format, at about 12 MB). The map accompanied a report: Taylor, G.C. and Stott, D.F. 1973. Tuchodi Lakes map-area, British Columbia. Geological Survey of Canada, Memoir 373. Unfortunately, this one isn't available online, AFAIK.

Howard, Calgary, AB

Dave S. said...

Nice work! I had it pegged as the Canadian Rockies as well, but like Brian, I didn't go far enough north.

Silver Fox said...

I thought it would be pretty easy, because it looked like the Rockies to me, and there's only so many places to look where a river and road cut through them - at least that's what I figured, but I've been there several times, so I'm probably no judge!

Thanks, everyone for all the great info! Ron, you didn't invent the Schott Rule, but did agree to it! Anyway, Peter will catch up, and then you guys can trade back and forth! :)

Brian, I thought you might get this one because the area is near or in the midst of a petroleum region.

Howard, the map and cross-section link is a good one; I had been trying to find that map, but didn't know where to look. I don't like the Mr.Sid interface that much - sometimes it works, other times I screw it up, but I saved them as pdfs.

Maybe you'all might be glad I didn't post an exceptionally close-up view of just Folded Mountain!

Peter's feed can be subscribed to:

In case I watch some movies or something! Besides, he will post a link right here.

Silver Fox said...

Dave, I guess everyone had the approximate right area!

Anonymous said...

Silver Fox--

"...I thought it would be pretty easy, because it looked like the Rockies to me, and there's only so many places to look where a river and road cut through them."

Yikes! This might be one of those cases where it helps NOT to be a local: I can see your logic, though--to a "furriner" I suppose only a few examples would pop to mind: Alaska Highway, TransCanada Highway, maybe the Yellowhead. On the other hand, I know about a zillion roads (most of them small, but it's tough to judge the size of the road from the GE image) that cut through the Rockies alongside a river--to my mind, it was a hopeless task. Guess I can't see the forest for the trees! I'll know better next time (maybe). :-)



Peter L said...

OK folks, WoGE #159 is up, and it's a free run, so you better hurry!

Silver Fox said...

Howard, I notice - now that I look again - that there are several roads (highways?) through the northern Rockies just south of the Sentinel Range area. Many of the roads I notice between there and the southern Canadian Rockies have lakes on them. I really thought it would be easy to look through that area, ruling out the southern Canadian Rockies quickly because they don't look right, mostly. But then, I knew where it was. And I also tried to make it a little obscure - it's perhaps harder to search when it's tilted.

A lot of the northern Rockies have a snow-capped-mountain white texture; these have a bedrock white texture that looks a bit different. Ah well. I haven't won very many!