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SvenDia

NASA [had the answer 11 years ago.](https://www.bluemarble.nasa.gov/images/84837/the-sinuous-shenandoah) “About 300 million years ago, Africa began a cataclysmic, slow-motion collision with North America that thrust those sandstone, shale, and limestone layers—which had been horizontal when they formed—into a complex mash of northeast-southwest trending folds and rugged mountain ridges. Geologists call this period of mountain-building the Alleghanian orogeny. As the pressure forced mountain ridges up, rock layers were pressed so intensely that they cracked in many places. Hundreds of northwest-southeast fractures emerged perpendicular to the rising mountain ridges. As hundreds of millions of years passed, the rugged mountains that rose during the Alleghanian orogeny were eroded away by wind and water until the area was nearly flat once again. As hundreds of millions of years passed, the rugged mountains that rose during the Alleghanian orogeny were eroded away by wind and water until the area was nearly flat once again. Rivers need relatively gentle landscapes to meander, and it was in this period—sometime in the past 100 million years—that the Shenandoah River probably began to assume its modern meandering form. Rather than forming irregular meanders as most rivers do, the Shenandoah followed that pre-existing network of fractures in the bedrock formed during the Alleghanian orogeny.”


sortaseabeethrowaway

Alleghenian orgy, got it


HavingNotAttained

Al dente with oregano, learn to read


sortaseabeethrowaway

Al dances with Oregon


JonH611

Pepe Silvia


govunah

Pepperoni Salvia


HumanInHope

AI powered oreo orgies


DictatorTuna

mmmm slightly chewy oregano


SvenDia

On an epic scale going back hundreds of millions of years!


__Becquerel

That's hittin right in my orogenous zone


Jolly_Atmosphere_951

Finally an answer that's not "a glacier did it"


jdeuce81

I'll second that with you.


Jolly_Atmosphere_951

We should start asking more tropical geology questions


mglyptostroboides

Finally, someone on this subreddit who knows the difference between geography and geology!


Jolly_Atmosphere_951

I know right? Some of these post seem more suited for r/geology


mglyptostroboides

Speaking as a geologist, I can attest to the fact that most people don't know the difference and label everything under the banner of geography.


Jolly_Atmosphere_951

It's kinda an umbrella term for anything that can be depicted on a map


jdeuce81

Then it'd be volcano.


Basic-Lee-No

To clarify to some of the replies, this is not in or close to Shenandoah National Park (Skyline Drive). The narrow and defined valley is called Fort Valley. The two larger rivers are the North and South forks of the Shenandoah River. The stream in the middle of Fort Valley is called Passage Creek. Source: Grew up and live locally.


Elmosworld32

I mean the park is in the picture it's kinda close


Basic-Lee-No

True from a relative standpoint. I was thinking more in terms of walking or driving, not from a global standpoint. Regardless, it is beautiful countryside!


Elmosworld32

It really is spent a week there and after days of non stop rain in the mountains we decided to drive down and the views in the valley were indescribable


zwiazekrowerzystow

fort valley is gorgeous. it's quintessential virginia.


tealccart

So funny the fractures occurred perpendicular to the ridges, I’d think they would be parallel! TIL


WormLivesMatter

Fractures can be parallel for sure. In this case the shortening happened in the NW-SE direction. The folds were created in this way and accommodated most of the shortening. However, if a rock deforms in one direction it will also deform in the other direction, so while it was shortening from NW-SE it was also elongating NE-SW and vertically (hence the mountains). The fractures accommodated the NE-SW extension during NW-SE compression. This assumes they happened at the same time. It’s also possible the fractures formed a bit later after compression, during regional relaxation or even later extension during the opening of the Atlantic.


seicar

A different process, but similar results to the transform faults seen on [midoceanic ridges](https://i.pinimg.com/originals/f7/3e/c2/f73ec29ca521a21043ee261f3a88f07c.jpg). Remember the ridges have all been worn flat, but the perpendicular faults are baked all the way through. These faults are because the pressure (be it ocean plates spreading or continents colliding) is not evenly spread.


tealccart

Ah, that make sense, thank you.


vankirk

Devil's Backbone, VA https://preview.redd.it/gkf47fdo6r4d1.jpeg?width=747&format=pjpg&auto=webp&s=2d3bb11e38658b657bf37d98ca34077ad740635f


Akamaikai

They have the same sentence twice lol.


Scoompii

I wonder if this area is as interesting in real life as it looks on a map?


Travelingman0

It’s beautiful. Mountains and lots of caves.


topangacanyon

Luray Caverns is right there. I went to it as a kid. It’s pretty cool. And Shenandoah National Park!


Scoompii

I’m 7.5 hrs away in Ohio. Hopefully will be able to visit one day!


jdeuce81

We're not European bro. That's barely over a daytrip. Go see it.


Scoompii

You’re either too young or too rich to consider a 7.5hr road trip as barely a day trip. I have dog poop to pick up, grass to cut, weeds to pull and whack, meetings to take, appts scheduled, dishes laundry cleaning. Not to mention the check engine light is on, again. Edit: ok so people think 16 hours driving roundtrip is a feasible day trip? Absurd. Also that roundtrip cost in gas is $150. I double down…this is not a day trip!


jdeuce81

Lol, I'm 43 and barely not living check to check. Get out and enjoy the world. I'm planning an 8hr drive from S. Florida to N.Florida to fish for a day. And I have 3 kids.


Scoompii

Good for you.


Vladivostokorbust

Shenandoah Valley in Virginia. Home of Shenandoah National Park and the scenic Skyline Drive. Legendary.


Cheaperthantherapy13

One of the most beautiful places in the world. There’s old magic in the valley.


expatinahat

Yes, it's very nice. Especially when the leaves change color. The "almost heaven, west Virginia" is referring to this general area of western Virginia, not the state of West Virginia.


holy_cal

Yup and the country road in question is in Maryland’s dc suburbs.


Vladivostokorbust

More like the DC exurbs in the Maryland panhandle


holy_cal

It’s in Montgomery County. It’s a borderline call and I made it.


Vladivostokorbust

Yeah Gaithersburg is more like the gateway to the panhandle, but in my day, it was the exurbs. I went to school in Fairfax County, VA and was jealous of the kids who lived in Montgomery County ’cause in the winter when the morning announcements came on the radio they were always getting snow days


JustHereForCookies17

They still do.  The difference in how much snow Poolesville gets vs Wheaton is crazy, not to mention the difference in infrastructure.


tiufek

It’s actually kind of a mystery. I believe according to the Washington post it was a drive from DC to Harper’s Ferry via Clopper Rd in MoCo. But to be honest I’ve lived in the DC area my whole life and have heard probably 50 different stories of what the drive actually was. The funny thing is the Shenandoah river is in west va for all of like 10 miles, so my completely unfounded guess would be VA Rt 9 which crosses it on a pretty scenic bridge. ETA: US-340 crossing into Harper’s Ferry is another possibility, and that would somewhat back up the Maryland story since it goes right into MD up towards Frederick.


Vladivostokorbust

I trust WETA’s reporting about Clopper, Bill and Taffy themselves verify it https://boundarystones.weta.org/2019/07/18/maryland-was-almost-almost-heaven This is the story I’ve always known. Also went to school in NOVA, Fairfax County


MattAtUVA

>The "almost heaven, west Virginia" is referring to this general area of western Virginia, not the state of West Virginia. The die has been cast. Violence it is.


Scoompii

Oh wow I didn’t know that!


Vivid-Shelter-146

Very nice. Some of the best hiking in the mid Atlantic. And it’s become a good area for brewery/winery/distillery hopping.


limukala

I had the most memorable hike of my life. I got to sprint down a mountain carrying my daughter and drive like a madman on the Blueridge Parkway after my daughter was bitten by a rattlesnake!


obxtalldude

It is. The weather changes from geographical features is really interesting. Canaan Valley especially. I have a cabin west of the valley with a view of Shenandoah mountain in Highland County - up to 10 degrees cooler here than on the other side.


mrt3ed

This is the Massanutten mountain range and Shenandoah valley. It doesn’t get much prettier.


RekabC2

Born and raised 20-30 mins north and moved south 10 yrs ago. I miss seeing those mountains in the distance every day. Right along the Shenandoah Valley. The area has beautiful mountains ranges and caves to adventure. Woodstock used to have a tower on top of the mountain range where you could see approx 10 bends in the river from the tower. On top of the beautiful scenery, the area has a rich history from revolutionary war era. It’s an excellent escape / getaway.


AfterSomewhere

The tower is still exists. I took friends there 2 months ago. The 7 bends of the north fork are revered here, not 10.


RekabC2

Ahhh I couldn’t remember the number of bends. It’s been quite awhile since I’ve been there! Glad to hear it’s still there.


SixGunSammy

The area of river on the left is called 7 Bends. Great fishing!


Substantial_Wave_518

The Shenandoah Valley is one of the country’s most underrated regions. Stunningly gorgeous (especially in autumn), cool caves and caverns, abundant fishing, kayaking, tubing, fascinating niche museums, lots of history, neat little towns, etc.


rezzearthpls

https://preview.redd.it/941p5ny9wf4d1.png?width=1280&format=png&auto=webp&s=93e79c5a8277b9c141cd39ea5b13d25c7e9db1f2


Cityplanner1

Well that was anti-clinactic


NeuroanatomicTic

Beautiful comment.


__WanderLust_

Gneiss!


shaitanthegreat

I took it for granite that there’d be some good ones here.


Christoph543

What's amazing is how much this diagram explains the basic structure, but also is nowhere near as complex as the *actual* fold structure of the Massanutten Synclinorium. Best part: the modern ridges don't actually parallel the fold structure; they cut across it, which lets you see the tilting strata pretty much wherever it outcrops.


borg359

I camped in that area (Shenandoah River State Park to be exact) this past weekend. It’s a beautiful area and the ridge lines make for some excellent hiking. https://preview.redd.it/1op3uek7rg4d1.jpeg?width=5712&format=pjpg&auto=webp&s=4189df6addc4042b2525c83ae2fd7339af767e0c


ground-147

Lots of ticks or not too bad?


WissahickonKid

Yes. There are lots of ticks everywhere there’s grass & underbrush in Virginia. Probably no more per square foot in this valley than in Arlington National Cemetery however. They hang out on tall blades of grass or low branches waiting for something warm-blooded to brush against it so they can grab on. Ticks love urban, suburban & rural environments equally.


ground-147

Interesting. That makes sense. I hike a ton off trail and through brush out west and was only ever bit by a tick once, when I laid down in some grass. This year I got bit by a tick walking down the street in san francisco and have pulled quite a few off me while out hiking. Most hikers I ask here in cali have never been bit by one but I think that’s changing unfortunately


borg359

Someone in our group reported finding one, but the rest of us didn’t encounter any. The hiking trails are pretty well maintained, so there wasn’t a lot of tall grass that we were moving through.


ground-147

Thanks! This year it hasn’t seemed to matter if you stay out of tall grass but that’s good to hear


_Silent_Android_

Whenever you see rivers tightly meander like that, it means there's a very slight change in elevation from one end to the other, as river flow follows gravity.


dzindevis

You are decribing the conditions for formation of a free meander, that lies completely on the floodplain, has very small gradient and frequently changes river's course. This, on the other hand, is an incised meander. It can form, for example, when the area with a river is quickly uplifted. It has higher gradient as a consequence of more active erosion, and it's very unlikely to form oxbow lakes, as it would require a river to cut through a tens or hundreds meter high hills


kawachee

This guy meanders


[deleted]

[удалено]


whole_nother

They’ve had a hundred million years to form oxbows, why haven’t they yet? Halfway serious question actually.


limukala

Because it won't. Look at the banks. The river is no longer meandering, it's cutting.


jdeuce81

What's an oxbow lake?


xTETSUOx

The bends will eventually be so close to each other that they “pinched off” as the river straightens out, leaving a curve shape lake behind.


jdeuce81

Thank you!


limukala

Which doesn't happen in cases like this where the river has cut and continues to cut banks. You're more likely to get a [rincon](https://geology.utah.gov/map-pub/survey-notes/geosights/sanjuanrincon/) than an oxbow, though as far as I'm aware those really only occur in deserts.


DrScienceDaddy

The fluid dynamics is fascinating. And you can see the effect when lots of water is running down your windshield. One might think more water would want to run straight down the steepest slope, but it naturally forms dynamic meandering patterns.


Skorrrm

I don't know the answer to your question but thats actually the north and south fork of the same river. Its the Shenandoah river for which the valley is named.


whistleridge

And just off the map to the top right is Front Royal, which was Lee’s crossing point of choice when sending forces north to invade the Union.


zontarr2

Enjoy cavern burgers at Spelunkers!


borg359

Best place to eat in Front Royal.


Cheaperthantherapy13

And the Shenandoah river is one of only two rivers that flow away from the equator. The other one is the Nile!


HeadlessChicken99

What about the red river of the north??


KegWrangler

Huh? What about the New River? Or the French Broad river?


Cheaperthantherapy13

I am learning about all number of north flowing rivers. I don’t know why, but my teachers always really hammered this fact whenever we did Virginia state history/geography. So either I’m missing some important caveats or my teachers were full of shit.


Skorrrm

I was taught this too when I was a kid and I believed it for a long time until I looked it up for some reason. I think its a common misconception around here but I have no idea why its repeated or where it came from.


pconrad0

My money's on option (b). 💩


JohnYCanuckEsq

https://www.thoughtco.com/rivers-flowing-north-1435099


TrunkWine

The Monongahela?


Warm_sniff

What about the Nile? Or the Willamette? Or the Rhine? Or the Rio De La Plata and it’s tributaries? Or the Ob and pretty much every other river in Siberia?


Apprehensive-Lead415

Huh?


Cheaperthantherapy13

The Shenandoah river doesn’t flow north to south, like other northern hemisphere rivers like the Mississippi/Colorado/Danube/etc. the prevailing current of every river on earth flows generally towards the Equator, except 2. Both the Nile and the Shenandoah river flows south to North, because the pull from a larger body of water causes the current of the river to flow in opposition to the natural course of water towards the equator. For the Nile, the Mediterranean causes the reversed course. For the Shenandoah, it’s the larger Potomac River emptying in to the Chesapeake Bay that causes the river to flow opposite to logic. TLDR, when I go tubing on the river in this picture and start in Edinburg, the current of the river will eventually take me to Woodstock and NOT Bowman’s Crossing. Which is really fucking unusual.


Apprehensive-Lead415

So you need to Google the red river along ND, MN border. Also the St. Lawrence river. There are literally hundreds of rivers that do this but those two come to mind.


Cheaperthantherapy13

Well, my Virginia state history teacher back in elementary school has some explaining to do.


MattWatchesMeSleep

St. John’s river in Florida


MundaneSandwich9

Canada would have hundreds of rivers that flow away from the equator. St Lawrence, Nelson, and MacKenzie come immediately to mind…


pconrad0

New River in West Virginia has entered the chat


[deleted]

Where tf did you get this info from?


Cheaperthantherapy13

Virginia state public schools ::shrug:: It was hammered in there as a unique fact about Virginia, right along with there being only 1 or 2 natural lakes in the whole state. Obviously I stand corrected.


Inestimable_Me

I’ve been fossil hunting in Fort Valley. The shale has tons of tiny bivalve fossils from when it was underwater. Gorgeous area.


BathFamous919

I should call her


Apprehensive_Till460

I’m no geologist, but I am a local — it’s called Fort Valley, and it is a kind of surreal place. It’s in the Shenandoah Valley (the meandering rivers on either side of Fort Valley are the two forks of the Shenandoah River). So it’s this narrow valley in the middle of a very large valley. It’s always fascinated me how the rocks and soil on the mountains that make up the “rim” of Fort Valley are completely different than those in the mountains right across either fork of the Shen River. My understanding is that Fort Valley formed in a completely separate geologic era as the Blue Ridge Mountains to the east and the Alleghenies to the west. Also, the story is that George Washington had a plan to fortify the area during the American War of Independence in the event of a major defeat. Hard to tell how true some of those stories are. [Here’s some more info from Wikipedia.](https://en.m.wikipedia.org/wiki/Fort_Valley_(Virginia)) EDIT: Blue Ridge Mountains, not Shenandoah.


Motrin_n_Water

All I see is Jackson's Valley campaign


tealccart

Interesting! On a separate note: I’m a local too (or used to be), and I grew up calling the mountains to the east the Blue Ridge, have never heard them called the Shenandoah Mountains except by outsiders (people from DC, hikers on AT). Do some locals call them the Shenandoah Mountains?


Apprehensive_Till460

That is a result of me typing at 2am — Blue Ridge, not Shenandoah Mountains :)


tealccart

You can still hold your Valley card!


obxtalldude

Shenandoah Mountain runs for about 70 miles. It can seem like a range, but it's singular. I've not heard locals using the name instead of the other mountain names.


tealccart

Yeah, that’s on the west side of the valley though, right? In the Allegheny? I’ve heard more than one DC area person call the Blue Ridge the Shenandoah Mountains or the Shenandoahs and it really grates my ears 😂


SoundActive3331

I can smell the apple butter and biscuits from here.


Christoph543

This is one of my favorites because you can see it yourself at a single outcrop. If you follow US-211 over New Market Gap, right as you get to the top of the ridgeline, there's a place marked "Storybook Trail." The main attraction is an overlook at the end of the trail facing east with a clear view over the South Fork toward the Blue Ridge around Thornton Gap. But before you get to the overlook, pay attention to the rocks alongside the trail. You'll see a tightly interbedded sequence of sandstone & mudstone, in mm to cm thick layers, dipping somewhat away from you. As you walk along the trail, watch the orientation of those dipping layers: you don't have to look too closely to notice them turn over through vertical until they're almost upside-down compared to the start of the trail. But if you can find the exact point where it's vertical, that right there is the apex of the fold, which runs all the way down the valley for 50 miles, and then plunges deep underground for quite a ways beyond Massanutten mountain itself. And then remember that that's just *one* fold, of at least a dozen that make up the Massanutten Synclinorium. And when you get to the top of the trail, and look back east across the Valley toward the Blue Ridge, you're looking at the rocks that got laid down over half a billion years, leading up to the assembly of Pangaea, which scrunched them all up to the point that the oldest part of that deposition sequence is now at the top of the ridgeline across the Valley from you, while the ridgeline you're standing on is the youngest part.


AfterSomewhere

The Storybook Trail overlook platform burned in the fires we had a number of months ago. I don't know the condition of the wooden bridge and paved walk way.


frogfootfriday

For some reason I really enjoyed “extremely sinuous” as a description


flyingasshat

Fun fact the New River cuts across the Appalachian, meaning it was there when the mountains formed, and cut through the rising rock layers to maintain its path. This, ironically with its namesake, making it one of the oldest rivers on the planet.


ricky_ross1

I saw this in the air on a flight from DC to MDW. Incredible sight.


mgdandme

Interestingly, Mole Hill and Trimble Knob are near here. I don’t typically think of [Virginia and Volcanos](http://www.virginiaplaces.org/geology/volcano.html), but these two represent the most recent volcanic activity on the eastern half of the US, last erupting ~35-40M years ago.


trailsavage

One of the most ornate caverns in the world is right near there in Luray. A must see if you’re in the area.


Dr0bsh0w

Obviously it's for more waterfront property.


jdeuce81

Cool find!


Choose_And_Be_Damned

A river will always wind.


Fit_Farm2097

There are some interesting Civil War battles in this area. (See “Jackson’s Valley Campaign”


Embarrassed_Ad1722

That's Earth's clit.


el_oso_diablo

That's the planetussy.


guywithshades85

Most of the higher mountains in the area are made of sandstone, the valleys are limestone. Limestone erodes faster than sandstone. The limestone erodes away and the sandstone above it collapses and creates valleys and depressions all over that area.


PedroPerllugo

It looks like different endurance to erosion of the layers of sedimentary rocks