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| The northern portion of Graham Island, with Rose Spit on the left below the wing, and Maset Sound in the upper right. |
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| The waves around the spit were reflecting in a bright, yellowish glare from the mid-day sun. |
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| A closer view of the convoluted shape of Rose Spit and its associated small islands. |
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| A view of the spit, with a few of the small islands off its tip. |
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| Dean Channel on the left, Burke Channel on the right. |
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| Google Earth image almost identical to my first photo. Dean Channel is on the left; Burke Channel is on the right. |
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| A photo zoomed in on Burke Channel. |
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| Google Earth image with Burke Channel centered, similar to the previous photo. |
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| Zoomed in photo with the mountain in question in the distance. |
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| Google Earth view, with the North Bentinck Arm of Burke Channel on the left and the South Bentinck Arm heading southward to the right. |
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| Google Earth image: Thunder Mountain is the highest peak in the center; Tzeetsaytsul Peak is the next highest peak to the left (north). |
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| Google Earth view of Tzeetsaytsul Glacier on the east side of Tzeetsaytsul Peak and Thunder Mountain; north is to the right. |
My two posts on Folded Mountain are perpetually popular, at least from searches, so I've put together this mini-series of roadside geology along the Alcan, or Alaska Highway, or Highway 97 (British Columbia). If I knew more about the geology along that road, I might post more of my photos from my several trips.
The March, 2010, version of Where in the West (WITW) is really just an excuse to post a glacier picture or two.
Just a quick preview of a roadcut on Highway 36 near Susanville, CA, showing a basalt flow over some white [probably tuffaceous] lake sediments. The reddish baked zone 
Callan Bentley at Mountain Beltway has had a couple posts up recently about mud cracks.
Three years ago today, while driving between somewhere and somewhere else, I came upon this cool oasis in the greasewood zone below the sagebrush steppe on the northeast side of Honey Lake, CA.
I took a road trip last week, south into Big Smoky Valley (MSRMaps), in order to grab a few photos from areas I visited in 1976 while on my thesis hunt.
I just returned from a mega-trip with MOH into central Oregon, where I met with family at an annual reunion-type affair on a basalt-capped bluff overlooking a small Oregon town.
Where in the West, if you might remember, features some [unknown] location in the western part of the northern hemisphere.
Also seen at Rose Spit:"dissipative beaches backed by prograding foredunes on North Beach; reflective cuspate cobble beaches with a sandy low tide terrace on NW Rose Spit; and multiple-barred beaches backed by migrating foredunes and parabolic dunes on East Beach."Pictures of these features — and much, much more — can be seen here, on page 3 and 4 of the pdf.
"Megaripples, sand waves and sand ridges are particularly important in the vicinity of Rose Spit and Rose Bar at the northeast corner of Dogfish Bank. These features are the result of storm-driven sand motion on the shelf under the influence of topographic steering of tidal and wind-driven currents. In this area amplitudes of the sand waves and sand ridges can exceed 6 m. "
"The eastern coastline of Graham Island is largely dominated by a thick sequence of unconsolidated glacial outwash deposits capped locally by Holocene dunes. These sediments are retreating rapidly, with the eroded sediments being swept northwards towards Rose Spit. While average erosion rates apear to be about 1 m per year, retreat is highly episodic; in 1992-1993, for example, 11 m of land was lost at Cape Fife and 1.5 m was lost in a 24-hour period at the same site in 1994. Numerous, ephemeral shore-attached bars are associated with the high rates of longshore drift along eastern Graham Island. "View Rose Spit at Flash Earth.
Where in the West, if you might remember, features some location in the western part of the northern hemisphere. This time, the unknown area includes water - a fair amount - mostly likely ruling out Nevada and any other intermountain state! Both photos, taken from an airplane, will enlarge somewhat.
Where is this place, and what are some of the landforms?
This oblique southeasterly view of the Sentinel Mountains from Google Earth shows the general area from a little higher than roadside level; that's the Alcan, AKA Highway 97. The topography of the same area, looking straight down and with the north arrow cocked to the right, can be seen here in The Atlas of Canada.
The picture I took looks like this; it corresponds with the two central peaks from the Google Earth image, with just a little of the pyramidal-shaped range-front hill on the far left.
Drawing on a composite set of photos, I came up with this pen-and-ink interpretation, which shows the general flat-lying nature of the sedimentary horizons away from the range front and to the east. The beds are then tilted into a dip slope right along the range front, forming a set of triangular-shaped facets, which I described more completely earlier. If you look carefully at the photo and the sketch, you'll see that they match up imperfectly - the sketch makes the farther hill appear a little larger than life. It is a cartoon.You'll find references, in-post links, more photos and images, and more about the Alcan and general geology in the previous posts.
Muncho Lake, a scanned postcard version.
Continue to the west and then north on the Alcan, beyond Folded Mountain. After stopping to view Stone Sheep (or Stone's sheep - Ovis dalli stonei) in the highway (a common site), you will come to Muncho Lake, about 36 km from the Folded Mountain turnout. Just so you remember where you started from and have some idea of where you're going, in this topo map, Folded Mountain is in the lower right, just to the left of the Nonda Creek label; Muncho Lake is prominent toward the upper left.
Above, I've more or less duplicated the postcard view of Muncho Lake with an image from Google Earth. We will be zooming in on a portion of the range front below, in a Google Earth view looking north from a height of about 472 ft (144 m) above ground level (I forgot to switch to meters in my new Google Earth version 5 right away!). The closeup focuses in on the third of several triangular-shaped mountain faces above, and it shows most of the second face in the foreground and part of the fourth face (and beyond) in the background.
These triangular-shaped range faces are dip slopes, with the carbonate beds dipping almost entirely parallel to the faces. These shapes could be called triangular facets, though they are not strictly fault-caused - nor are they the result of truncated spurs - and they are reminiscent of the flatirons along the Rocky Mountain range front in Boulder, CO, though bedding there dips eastward, and bedding above dips westward. Locally, these shapes in the Sentinel Range are called sawteeth. [If there is a better geomorphic or descriptive term for these triangular shapes than what I've used here, I wouldn't mind some input!]
This photo, taken in 1996 from the north end of Muncho Lake, duplicates the Google Earth image above (or the other way around), and shows the beds dipping parallel to the range front slope. The drawing below highlights the bedding.
So, from Folded Mountain, here, we've gone to this northern end of Muncho Lake, here, and are centered in on the triangular part of the range front at the very north end of the lake, here.
Just pretend that you are still on the Alcan, in that in-between place between Toad River and Muncho Lake in northern British Columbia, Canada. You've just driven to the famed Folded Mountain turnout, pulled out to read the sign, and are now looking at Folded Mountain. If you look to the north, you'll see views like the two I've so cleverly created from Google Earth: the first one, above, looking north from about 450 m above the ground; the second one, below, looking north from just as close to ground level as I could get Google Earth to go, 60 m above the ground.
I don't usually have a hovercraft with me while driving the Alcan, so I usually look at things from ground level, having never spent enough time on the highway to do any hiking around. A hovercraft could, however, be a useful thing to have on this supposedly paved highway: it always seems like major - I mean major - road construction is in progress somewhere along the way. Too bad I don't have photos of some of the boulder fields I've driven through on the supposedly paved highway.
Suprisingly, a 1993 photo taken from or near the Folded Mountain turnout looks very similar to the second Google Earth image, but in the photo you can actually see some of the folds. And someone has drawn on the photo, approximately outlining some of the folds. Please ignore the pen lines on the upper part of the mountain - that part is too obscure for drawing to be of any use whatsoever - without having the actual mountain handy (which it's not).
And here, above, is the greater Fort Nelson to Liard Hot Springs region of British Columbia, Canada. Liard River is a tiny community at Mile 496 (HM) of the Alaska Highway; Liard Hot Springs, aka Liard River Hot Springs, is at Mile 497 (HM). I note the location of the hot springs on the image above - rather than that of Liard River - well, because the springs are a great place for a soak if you happen to be passing through.
Zooming in a bit above, we can see our particular area of interest better: Muncho Lake, the NNW-trending Sentinel Range of the northern Rocky Mountains, and Folded Mountain (link to topography provided by Ron Schott).
Here's the Google Earth shot I considered using for WoGE #158. It's an image looking west, from one point on the highway where one can stop and take a photo.
And this is what that image would look like at near ground level, just about what you would see while driving west on the Alcan.
A photo! Now we can begin to see why it is, at least locally, called Folded Mountain.
Folds!
Close-up of the same folds!
And closer still, from a postcard I probably bought back in 1998 at The Poplars.
This is the sign at the Folded Mountain turnout, right at the eastern base of the mountain, at mile 409/km 658 (current mile/km):Originally, all the rock of the British Columbia Canadian Rockies lay flat on the shallow sea bed of the western continental shelf where it had accumulated grain by grain over a billion years. About 175 million years ago the continent of North America began to move westward, overriding the Pacific shore and colliding with the offshore chain of islands. The continental shelf was caught in the squeeze. The flat layers slowly buckled into folds like those you see here. As time passed, folded mountain ranges sprang up across British Columbia. By 120 million years ago, the Rockies were showing above the sea. They grew for another 75 million years, rising faster than erosion could tear them down - likely reaching Himalayan heights. Active mountain building ended in the Canadian Rockies some 45 million years ago. The peaks have since been eroded to a small fraction of their original size.Additional and more detailed geological information can be found in the comments of my WoGE #158 post.
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!!
Just a few summaries and links to mining and exploration stories out recently. Excuse some dorky titles. How can you tell which titles are dorky? Easy, the dorky ones are mine.
