The Whites - Pre Glaciation

[dr_wu002]

I wonder if anyone can use the Hubble Telescope to look back and snap a few photographs of the Whites and what they looked like 12,000 years ago and beyond! If the Hubble can look at the universe a few seconds after the Big Bang then it shouldn't be too difficult to see a few thousand years ago on Earth!

-Dr. Wu

 

[Rugger]

Concerning the rebounding of the New England crust. My geography prof. from UVM claimed that in several thousand (can't remember how long) years, if nothing were done at the Northern end, Lake Champlain would start to drain south because Norhtern Vermont was rebounding faster.

 

[^MtnMike^]

I wonder if anyone can use the Hubble Telescope to look back and snap a few photographs of the Whites and what they looked like 12,000 years ago and beyond!

Unfortunately, no (that would be cool though! )
In order to see something as it was 12,000 years ago the Hubble Telescope has to be roughly 12,000 lightyears aways from it.

^MtnMike^

 

[DougPaul]

Unfortunately, no (that would be cool though! )
In order to see something as it was 12,000 years ago the Hubble Telescope has to be roughly 12,000 lightyears aways from it.

Unless you can find a rather strong gravitational lens 6000 lightyears away.

But it would probably distort the image.

Doug

 

[dug]

Still working on the kinks on my time machine. Last test subject I sent back I haven't heard from. If I get the flaw figured out, I'll be sure to let you guys know. Damn DeLoreans.....

 

[jjmcgo]

Torngats felsenmeer

Dear Papa Bear,
I Dogpiled felsenmeer and got this brief article on Torngats felsenmeer.
http://cgrg.geog.uvic.ca/abstracts/MarquetteStudiesOver.html

Here's a brief and interesting website on the geology around the Huts and it has links to other N.H. geological information.
http://www.coloradocollege.edu/Dept/GY/faculty/wphillips/web page.htm

I really enjoyed this thread and learned a lot.

So, felsenmeer is not synonymous with scree? It is one type of scree? Scree seems to define all loose rock, regardless of origin. Still trying to learn here.

 

[Papa Bear]

So, felsenmeer is not synonymous with scree? It is one type of scree? Scree seems to define all loose rock, regardless of origin. Still trying to learn here.

I'm not a geologist, but I would say "scree" is a generic term which refers to weathered material on slopes. Most often Scree is loose and fairly small grained (i.e. gravel) although the term is probably applies to a variety of surfaces. It's origin is most probably from erosion of running water, but some freeze/thaw weathering may play a part. In the Whites you would find "scree" on slides, e.g. the Lincoln Slide. In the Torngats it's probably more widespread since there are no trees.

I would say Felsenmeer is not a type of Scree since it is not loose (the rocks don't move) and certainly not small grained.

Interestingly this thread's title is "The Whites - Pre Glaciation". Felsenmeer is certainly a post-glaciation phenomenon and being above tree line, is likely to be fairly permanent. Scree OTOH, (excpt for morains such as Long Island and cape Cod) are probably very recent, and not permanent.

Eventually the scree covered slides and loose slopes get vegetated (maybe over a period of hundreds of years) and the scree will become soil. Of course new scree will form from new slides, new eroded areas (from logging, fires, etc.) and the cycle goes on.

Beyond that, I would say a geologist needs to chime in here.

 

[Puck]

Speaking of skree...I have a question/observation. One effect of glaciation are the eskars. I understand that these can appear as a low ridge in a valley and are mainly comprised of gravel and breadloaf sized rocks. When I hiked Cannon I kept thinking that the lower part of the mountain, the loose gravel that has eroded out, cuold have been deposited by the same mechanism that forms eskars, a stream of melted ice flowing under the glaciar. Or it may have been formed like a morraine, left as the glaciar advances or retreats. My understanding is dunlins, eskars and moraine are made up of debris from glaciar and could be identical in composition, however, it is the mechanism under which they were formed defines them.

We could use a geologist on this thread.

 

[dug]

A terminal morraine is at the end. Kind of like a snow plow. As the glacier advances, it pushed all the crud along. When it retreats, the morraine is what is left. There are morraines on the sides (can't remember what they are called).

When you have meltwater on a glacier, a stream will run underneath it. Kind of like a culvert underneath a road I guess. That stream is filled with debris, and when the water stops and the glacier retreats, the eskar is left over.

A drumlin, I THINK, is similar but bigger.

All are similar in nature, but I think the debris size will get bigger as you go from eskar to drumlin to morraine. For example, Long Island and Cape Cod are terminal morraines.

I can't picture the spot on Cannon you are referring to.

 

[Rugger]

If I remember correctly, a drumlin is kind of like a bubble of debris (mud & rocks) being moved along under the glacier. When glacier returns North, the "bubble" dries out to become a cute little rounded hill.

 

[dug]

Good description. A drumlin can be HUGE. The sand pit area visible behind the Burger King off I-93 Exit 24 is an example if I recall.

My college profs will either be:

a) Proud of what I remember, or
b) Extremely disapointed in me

 

[Puck]

An example of a dunlin that I have read about are the hills around Boston. Breed's Hill is one. Rugger, you explanation jogs my memory and it sounds right.

dug, I can stand on top of the basalt ridges in central CT and see the terminal morraine on Long Island. It is interesting that while New England was pressed under a glaciar, long island was...uh...dirt. I know morraines are formed by the glaciar pushing debris into piles which can occur in front of the glaciar and on the sides, as you said. There is also a morraine that builds up under the glaciar. I don't remember the term.

The place in Cannon is at the start of the trail from the ski area parking lot. The trail has high embankments of loose gravel on both sides. The trail seems terribly eroded. On other trails in the Whites erosion shows slabs of granite. The cannon trail is really unique. I thought that the gravel would be coveted by a construction company for fill. so happy the area is protected.

 

[Willie]

You guys are doing pretty well without a geologist. What you really need is a glacial geomorphologist. I remember just enough of this glacial geomorphology stuff from graduate school to be dangerous - I studied structural geology. Nevertheless, to summarize some of the terms that have been used:

A “drumlin” is an elongated hill or ridge of glacial till. It’s not clear how they form or why they form in some places and not in other places. Wisconsin is the land of drumlins.

An “eskar” or “esker” is a long, narrow ridge of coarse sediment and gravel deposited by a stream flowing under a stationary glacier. When the glacier melts, the eskar remains in the form of a ridge.

A “moraine” is an accumulation of sand, gravel and other sediment and debris deposited by a glacier. A “terminal moraine” forms at the leading edge of a glacier (as stated, Long Island is a classic example). A “lateral moraine” forms along the edge of valley glaciers. I don’t know about New Hampshire, but if you hike in the Adirondacks and look along the valley sides, you can observe lateral moraines.

“Scree” and “talus” is an accumulation of loose/broken rock. If it’s at the base of a steep slope, some will define that accumulation as scree. If it’s at the base of a cliff, some will define that accumulation as talus. The slope at the base of the Trap Dike in the Adirondacks I call a talus slope.

“Felsenmeer” is an accumulation of frost fractured rock without a cliff or ledge above as an apparent source. The summit of Mount Washington is a good example.

 

[Raymond]

Maybe you can find something on this lengthy page:

http://www.erudit.org/revue/gpq/1999/v53/n1/004882ar.html

I'm pretty sure there's an explanatory drawing displayed somewhere at Acadia National Park that shows that area pre- and post-glacier, but I can't find anything like it online.

 

[Dugan]

From what I remember, Willie is correct, lateral moraines are more along the sides, and are found especially as ridges of till that parallel the sides of valleys.

Another type of moraine is the medial moraine, unique to alpine areas. They're formed when alpine glaciers merge to create a single glacial flow. The result is that the till formerly carried along the mergine sides become a single stream of debris within the new, larger glacier.

Cirques also are a result of glaciation. A cirque is a bowl shaped depression with steep walls upvalley, and an open end down valley. They're typically formed in a deep "v" shaped valley as snow and ice accumulate and begin to form a glacier. As it enlarges, frost wedging forms debris and the glacier gathers that and other debris into itself. The WMG says that Great Gulf is the largest cirque in the Whites.

Also related to glaciers - If you climb Watatic, you can see marks in the rock at the summit where it was scratched by debris pushed along under the glacier as it passed over.

 

[DougPaul]

Cirques also are a result of glaciation. A cirque is a bowl shaped depression with steep walls upvalley, and an open end down valley. They're typically formed in a deep "v" shaped valley as snow and ice accumulate and begin to form a glacier. As it enlarges, frost wedging forms debris and the glacier gathers that and other debris into itself. The WMG says that Great Gulf is the largest cirque in the Whites.

Uhhhh... Glacial valleys are U shaped. (River valleys are V shaped.) A cirque is the head of a glacial valley.

Tuck, Ravine of Raymond Cataract, Huntington, and Great Gulf are all glacial. King Ravine, Jefferson Ravine, Madison Gulf, and Castle Ravine all look glacial from the topo.

Glaciers tend to form on the north and east side of mountains (less melting).

Doug

 

[Dugan]

Yes, DougPaul, they are now "U" shaped. However, pre-glaciation, they were "v" shaped. As the glacier moves through, it rounds the v to a u.

 

[DougPaul]

Yes, DougPaul, they are now "U" shaped. However, pre-glaciation, they were "v" shaped. As the glacier moves through, it rounds the v to a u.

Yes if the glacier is flowing down an established stream valley.

Doug

 

[HikerBob]

There is some great info in section 17, pages 361... of FOTH regarding glaciers. Check it out. Great illustration on 362 explains a lot.

Bob

 

[dr_wu002]

the Whites were thought to have rivaled the Himalayas, since the orogeny that created each is similar. The instructor said that the Whites were formed the last time the continents all bashed together. They formed a land mass that's today called Pangaea. Likewise, the Himalayan mountains are forming as the result of two different plates with land masses on the edges being forced together (Australian-Iandian Plate being forced northward into the Eurasian plate), which is how the Whites would've been formed.

Now I've heard this several times before (including from the geologist that I live with) and my question is, were the Whites these big, majestic mountains like the Himalayas or were they more a very high plain with large bumps on it? I'm trying to imagine something looking like the Himalayas being carved and whittled down into the small (but so loveable) White Mountains we know today. I realize that Pangaea was a long time ago (pre-civil war era, I think) and there have been many ice ages since then (?) which could have left their mark in the Whites but for me it's still very difficult to understand.

I'm a physicist (of some sorts... although most of those sorts are gone these days) and can understand some things but for some reason, glaciation is something that I find very difficult to imagine in my head. it's the time frame that kills me. I should go back to school for this stuff because A) I could understand it but B) and most importantly -- I'd get to move to Antarctica or Greenland or something and be freezing cold all the time! Bring it on!

-Dr. Wu