Forum Index > Trip Reports > Anderson Mountain (Skagit) and a bit of geology- 11/16/16
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Brushbuffalo
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PostWed Nov 16, 2016 4:33 pm 
I had run and skied up and down Anish Mountain (er, I mean Anderson Mountain wink.gif ) at least twice about 15 or 20 years ago before the "prominence interest " gained momentum, and now that I too am a "prominencer," if merely a casual one, it was about time for another look. There are at least three ways to the top: 1) the PNT from the west, 2)the road from the east, usually gated ,and 3) the mostly drive-up route from the south, assuming it is ungated.edit: "The DNR access road (Alger Mountain road) from the south is unlocked September 1 to December 31 annually." Thanks, anatoli! I had just half a day available today so I decided to see if the quick drive-up was feasible (#3), but if the road was gated then I would try the PNT (#1).
The road from the south was open. In fact south of the top there is a new clearcut this year (ugly as can be, but that's how they are for a few years), and it  led all the way up to about 3200 feet and half a mile from the top. (I could have driven a quarter mile farther but I want to preserve even the ol' beater truck).
The road from the south was open. In fact south of the top there is a new clearcut this year (ugly as can be, but that's how they are for a few years), and it led all the way up to about 3200 feet and half a mile from the top. (I could have driven a quarter mile farther but I want to preserve even the ol' beater truck).
Easy-peasy! You could actually drive this if you don't value the paint on the sides of your vehicle, but why? It is super easy walking/running/cycling, or skiing/snowshoeing with snow cover.
Easy-peasy! You could actually drive this if you don't value the paint on the sides of your vehicle, but why? It is super easy walking/running/cycling, or skiing/snowshoeing with snow cover.
Take the right fork here. On my previous trips up here, this was a brushfest. It has  since been brushed out and is easy walking. Thanks, volunteers!  I took my pruners and snipped a few branches, too, a good thing to do on our hikes especially on less frequented trails, don't you agree?
Take the right fork here. On my previous trips up here, this was a brushfest. It has since been brushed out and is easy walking. Thanks, volunteers! I took my pruners and snipped a few branches, too, a good thing to do on our hikes especially on less frequented trails, don't you agree?
Approaching the little saddle between summits.
Approaching the little saddle between summits.
Giant puddle at the saddle. You could almost canoe on  this thing!
Giant puddle at the saddle. You could almost canoe on this thing!
Passing the previous giant puddle,  I swung back right (south) and walked for maybe 200 yards and was delighted with this great view of Baker and the Sisters. North flank of Lyman Hill on right.
Passing the previous giant puddle, I swung back right (south) and walked for maybe 200 yards and was delighted with this great view of Baker and the Sisters. North flank of Lyman Hill on right.
Lyman Hill and valley fog.
Lyman Hill and valley fog.
It is hard to show in these photos, but there are several long (tens of meters), deep (meters), wide (meters) fissures that parallel the upper ridge of Anderson Mountain. These impressive fissures are called sackungen ( singular is 'sackung':) and are not uncommon in [url=https://washingtonlandscape.blogspot.com/search?q=Sackung]Western Washington's formerly glaciated foothills[/url], including on Blue Mountain west of the Twin Sisters, High Divide west of Welcome Pass,  south side of Goat Mountain ( Nooksack one), and many other places. We would notice them more if our " jungle" didn't obscure  them. Others are evident on the northeast side of upper Steamboat Rock in the Grand Coulee area. The sackungen on Anderson were probably formed after continental ice- which buried by about two thousand feet  the entire mass of Anderson Mountain- melted. The relaxation of confining pressure particularly from the sides facing the flanking valleys east and west resulted in the lateral gravitational sagging  of the uppermost part of the mountain in elongated fractures parallel to the long axis.  It's just a theory, and one that I happen to agree with :). However, prior glaciation is not always required to form [url=https://www.researchgate.net/publication/259400247_Criteria_for_Determining_the_Seismic_Significance_of_Sackungen_and_Other_Scarplike_Landforms_in_Mountainous_Regions]sackungen[/url], and similar-looking features of different origin can be found in both prior-glaciated and never-glaciated areas. Find lots of images on Google under the heading [i:c96d393015]sackungen.[/i:c96d393015]
It is hard to show in these photos, but there are several long (tens of meters), deep (meters), wide (meters) fissures that parallel the upper ridge of Anderson Mountain. These impressive fissures are called sackungen ( singular is 'sackung') and are not uncommon in Western Washington's formerly glaciated foothills, including on Blue Mountain west of the Twin Sisters, High Divide west of Welcome Pass, south side of Goat Mountain ( Nooksack one), and many other places. We would notice them more if our " jungle" didn't obscure them. Others are evident on the northeast side of upper Steamboat Rock in the Grand Coulee area. The sackungen on Anderson were probably formed after continental ice- which buried by about two thousand feet the entire mass of Anderson Mountain- melted. The relaxation of confining pressure particularly from the sides facing the flanking valleys east and west resulted in the lateral gravitational sagging of the uppermost part of the mountain in elongated fractures parallel to the long axis. It's just a theory, and one that I happen to agree with wink.gif. However, prior glaciation is not always required to form sackungen, and similar-looking features of different origin can be found in both prior-glaciated and never-glaciated areas. Find lots of images on Google under the heading sackungen.
View into the faux bottom of a sackung, with some garbage (a  car door) for scale. The slot is plugged with debris and may be considerably deeper.
View into the faux bottom of a sackung, with some garbage (a car door) for scale. The slot is plugged with debris and may be considerably deeper.
Cave entrance? Nope! Just before the big puddle, take this break in the forest to scramble to the top. When I previously visited here, it was a battle with slash and through tightly- spaced saplings. It is easy now due to interest and work by locals including new NWHIKERS contributor anatoli and many folks doing prominence summits. Thanks to those of you whose work has made the final part an easy walk instead of a thrutch!  :up:
Cave entrance? Nope! Just before the big puddle, take this break in the forest to scramble to the top. When I previously visited here, it was a battle with slash and through tightly- spaced saplings. It is easy now due to interest and work by locals including new NWHIKERS contributor anatoli and many folks doing prominence summits. Thanks to those of you whose work has made the final part an easy walk instead of a thrutch! up.gif
I didn't find the ropes that Gimpilator and others have written about. Removed as "litter?" I dunno, but I was on the obvious route up, as indicated not only by cut branches but by worn spots in the moss, logically-spaced steps, reminding me of brown bear paths in coastal Alaska.
I didn't find the ropes that Gimpilator and others have written about. Removed as "litter?" I dunno, but I was on the obvious route up, as indicated not only by cut branches but by worn spots in the moss, logically-spaced steps, reminding me of brown bear paths in coastal Alaska.
Thick moss covers the upper mountain. Looks steep (yes) and slippery, but is easy.  Hobbits sightings today: 0
Thick moss covers the upper mountain. Looks steep (yes) and slippery, but is easy. Hobbits sightings today: 0
People have done some trimming to improve the view from the top.
People have done some trimming to improve the view from the top.
Summit view, looking toward Samish Island and Samish Bay.
Summit view, looking toward Samish Island and Samish Bay.
Bedrock on Anderson is Darrington phyllite (as on Lyman Hill summit. Pronounced 'fill-light':), also with another metamorphic rock (Shuksan greenschist) at the large quarry on the approach road (not shown). This outcrop is on the road at about 2800'. Phyllite is notoriously bad climbing rock. Many years ago Rowland T. and young field assistant Brushbuffalo had at least one pretty scary time on it ...scary at least for me!....on the ridge between Winchester Mountain and Gold Run Pass.  :eek:
Bedrock on Anderson is Darrington phyllite (as on Lyman Hill summit. Pronounced 'fill-light'), also with another metamorphic rock (Shuksan greenschist) at the large quarry on the approach road (not shown). This outcrop is on the road at about 2800'. Phyllite is notoriously bad climbing rock. Many years ago Rowland T. and young field assistant Brushbuffalo had at least one pretty scary time on it ...scary at least for me!....on the ridge between Winchester Mountain and Gold Run Pass. eek.gif
Phyllite is a low/medium grade metamorphic rock formed from a sedimentary parent, in this case a carbon-rich shale or mudstone. The carbon came from plant material and is the reason this phyllite is dark in color. It is rich in graphite, a soft mineral that is pure carbon...same composition as diamond! If the parent rock is andesite or basalt and it is subjected to directed pressure during metamorphism, it becomes greenschist  (or greenstone if not foliated).
Phyllite is a low/medium grade metamorphic rock formed from a sedimentary parent, in this case a carbon-rich shale or mudstone. The carbon came from plant material and is the reason this phyllite is dark in color. It is rich in graphite, a soft mineral that is pure carbon...same composition as diamond! If the parent rock is andesite or basalt and it is subjected to directed pressure during metamorphism, it becomes greenschist (or greenstone if not foliated).
More phyllite. It resembles slate but due to more intense metamorphism, it is shiny due to larger (but still microscopic) mineral grains, foliated due to directed (unbalanced) pressure. Foliation is the planar structure and is not the same as stratification, which is a sedimentary structure due to layering. I took this pretty piece home, although I'm not a rockhound ( my wife questions that :) ).
More phyllite. It resembles slate but due to more intense metamorphism, it is shiny due to larger (but still microscopic) mineral grains, foliated due to directed (unbalanced) pressure. Foliation is the planar structure and is not the same as stratification, which is a sedimentary structure due to layering. I took this pretty piece home, although I'm not a rockhound ( my wife questions that wink.gif ).
Kid's playhouse or parents' escape cottage? Who knows, but cute, isn't it? This is near the base of the approach road.
Kid's playhouse or parents' escape cottage? Who knows, but cute, isn't it? This is near the base of the approach road.
Anderson Mountain is a delight, at least the upper portion. I plan on hiking the PNT route this winter when the snow is deep on top and maybe camping on top. It has just over 3 k of prominence.

Passing rocks and trees like they were standing still
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Matt Lemke
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PostWed Nov 16, 2016 5:20 pm 
I really like Phyllite!

The Pacific coast to the Great Plains = my playground!!! SummitPost Profile See my website at: http://www.lemkeclimbs.com
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RodF
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PostWed Nov 16, 2016 6:23 pm 
Sackung - thanks for the new word! - a scarp (trench) that may be mistaken for a fault, caused by creep, settling or slipping. "Most commonly found in Alpine glaciated regions near the crest of a range. Their origin is interpreted to be a result of post-glacial, gravitational spreading of the ridge crest and over-steepened ridge flanks." - CGS There are many in the Olympics; USGS geologist Roland Tabor shows a photo of one and called them "ridgetop depressions". They appear in a variety of weaker rocks with highly inclined bedding planes, including basalt and shale.

"of all the paths you take in life, make sure a few of them are dirt" - John Muir "the wild is not the opposite of cultivated. It is the opposite of the captivated” - Vandana Shiva
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Brushbuffalo
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PostWed Nov 16, 2016 6:24 pm 
Matt Lemke wrote:
I really like Phyllite!
Matt, you are really strong and if you pick up a huge chunk of it, will it "phyl-lite"? ( fill lite = feel light) (awful pun). mad.gif

Passing rocks and trees like they were standing still
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Sculpin
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PostThu Nov 17, 2016 7:41 am 
Sackung...that's pretty cool. I have long wondered about the bizarre, giant N-S fissures in the Tunk, east across the Okanogan river from Riverside. They go right up the ridge and down the other side, like slices through a bread loaf. But they are on a MUCH larger scale than the sackung shown here. They don't match any topographical feature I have seen anywhere else, nor can I find anything in the geological literature on them.

Between every two pines is a doorway to the new world. - John Muir
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Brushbuffalo
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PostThu Nov 17, 2016 8:28 am 
Sculpin wrote:
Sackung...that's pretty cool. I have long wondered about the bizarre, giant N-S fissures in the Tunk, east across the Okanogan river from Riverside. They go right up the ridge and down the other side, like slices through a bread loaf. But they are on a MUCH larger scale than the sackung shown here. They don't match any topographical feature I have seen anywhere else, nor can I find anything in the geological literature on them.
Sculpin, thanks for your interesting observation. I remember seeing what you are talking about when I drove by there this past September. Although resembling sackung, when looking at that area on Google Earth, but also considering the fact that that area was also glaciated by the Okanogan lobe, I have a different hypothesis for their origin and development. There are two sets of fractures there, indeed on a massive scale of hundreds of meters in length: one set oriented NW-SE and the other.....the really prominent set....running N-S. I believe these are joint sets in the Swakane gneiss of the Okanogan "dome" (not a classic structural dome but commonly referred to as such). Similarly scaled joint sets are not uncommon in granitic batholiths including the Sierra Nevada and are formed by oriented stress when the rock is deep in the crust. After uplift and erosion finally exposes the rock at the surface, differential weathering deepens the joints, gradually leading to the impressive fissures, bordering on 'mini-canyons' that you commented on. Since I don't know how to attach a Google Earth image, if interested just search for Riverside, WA and look east of the Okanogan River.....can't miss it!

Passing rocks and trees like they were standing still
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Sculpin
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PostThu Nov 17, 2016 9:30 am 
Thanks Dr. BB! The pattern continues up the side of the "dome" past Tonasket, so your interpretation makes sense. Since this is a hiking site, I should also point out that these fissures of the Tunk make for some nice scenery along with plenty of solitude (except in hunting season), great for off-season hiking. Its too hot in the summer. Some slots are open shrub-steppe and some are full of brush, while the ridges in between are open pine savannah. There are a couple small lakes in there as well. They are mostly on public land but access is a bit convoluted. I have spent a lot of time on that! The public land just kisses the road along the river in one location, but you have to park on the shoulder and climb over a cow fence. I decided not to. Old maps show a road climbing from the northwest up into the slots. It is still visible on Google maps but there is no turn-off or public access from the road anymore, no doubt obliterated by a landholder. You can access the slots from the Tunk Valley Road at the public hunting access parking lot and bridge across the creek. From there you can follow a closed road bed up and over, skirting around a private inholding, into the slots. Watch for the rare sage grouse, this location has one of the last remaining leks. No TRs on this area at nwhikers, maybe I will write the first next spring. Sorry about the thread bomb.

Between every two pines is a doorway to the new world. - John Muir
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Brushbuffalo
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PostThu Nov 17, 2016 10:04 am 
Sculpin wrote:
Sorry about the thread bomb.
Not a problem. Diversions are almost always interesting IMO. I go off on rabbit trails all the time, both literally while exploring and also in my posts on NWHikers (sometimes to the annoyance of the original poster, I suppose, but being annoying is never my intent). hijacked.gif Just read 'em, or don't. smile.gif

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HitTheTrail
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PostThu Nov 17, 2016 10:41 am 
Brushbuffalo wrote:
Matt, you are really strong and if you pick up a huge chunk of it, will it "phyl-lite"? (awful pun). mad.gif
Geologic question: What is an up-thrown block of metamorphic rock that has flat sheet-like mineral orientation? Answer: Horst Schist hockeygrin.gif

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Brushbuffalo
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PostThu Nov 17, 2016 11:02 am 
HitTheTrail wrote:
Geologic question: What is an up-thrown block of metamorphic rock that has flat sheet-like mineral orientation? Answer: Horst Schist hockeygrin.gif
Oh no, it continues... HitTheTrail, do you realize that a common volcanic rock is named for one of your five senses? It's true! You have your hearing, the smell, the taste, da touch..... andesite. doof.gif

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PostFri Nov 18, 2016 3:10 pm 
I would give that statement two thirds of a pun..........."P"...."U"......... cool.gif

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Brushbuffalo
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PostFri Nov 18, 2016 3:32 pm 
Lookout Bob, you are being gracious. I know even worse geologic puns but I will spare the reader from the pain! For now.... wink.gif

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PostMon Nov 21, 2016 2:20 am 
Wow! The route to the top is in way better shape than the last time I was there. Definitely would be nicer without all the slash piles and brush to contend with. I'll have to head up there again soon! Also, "Anish" mountain...haha. I ran a lot of double Andersons when I was training for HURT a few years ago, that's for sure!

"Our way is not soft grass. It's a mountain path with lots of rocks. But it goes upwards, forward, toward the sun." -Ruth Westheimer
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PostMon Nov 21, 2016 12:58 pm 
Great report double B. This looks like a place that would be ideal for bike 'n hike sorta things. Definitely have to check it out.

Karl J Kaiyala
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Brushbuffalo
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PostMon Nov 21, 2016 1:46 pm 
Karl ("Double K" smile.gif ), all of the foothills in Western Whatcom and Skagit Counties have good bike-n-hike routes. Anderson is probably best for biking via the east route (Gimpilator has a TR on NWHikers and there are maps on Peakbaggers that I linked). Also these hills have good snowshoe and xc ski routes, and the running is great! I as well as many others have spent many an hour on them in all seasons. I feel fortunate to have such places so close to home. Come on up to go 'sploring, and email me if you want a guide!

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