Sunday, October 25, 2009

10-21-09 The Mystery Around The Felsenmeer

My questions about the formation of the felsenmeerare: what agents, or factors, combined to cause the fracturing of the rock mantle that the continental glacier scraped clean and exposed to the elements, when did it start, did it occur over thousands of years or a shorter period of time, and whether the fracturing and movement of the blocks is still going on today? Looking down at the point where I took the photo of Cherry Mountain I was standing an an outcropping of the Littleton Formation that's the parent rock of the Presidential Range. The felsenmeer on the Presidentials is mostly made up of this metamorphic rock along with small amounts of intrusive white quartz. The process in the above photo, where the Littleton Schist has been compromised by cracks like this one, might represent a hologram for what created the felsenmeer. In this case the cracks have vegetation growing in them and some seasonal ice. The ice and plants could be seen as 'mechanisms' or 'agents' of the profound fracturing of the upper layers of the Schist over what must have been a big chunk of time on the human scale.

A closeup of a crack shows the simplicity of how it works. Water flowing downhill and carrying small bits of sediments is the usual agent that starts the crack, through erosion, and continues the process of deepening and widening the crack(wind plays a key role as well). Organic matter gets mixed in with sand to form the rudiments of soil. The soil, even if it's infinitely thin, will attract a seed, or two, that will immedately begin the colonization of the "niche" and then it is just a question of time before a more intense force is exerted on the parent rock. The freeze-thaw cycle is incredibly powerful. It's can lift tall buildings and destroy highways. I had a job years ago installing underground propane gas tanks to fuel heaters for large outdoor swimming pools that weighted tons. If there was frost in the ground and the tank wasn't filled immediately with propane the day it was buried the next day it would be sitting on the surface, pushed right out of the ground by the frost.

Ice. This is thin ice, 'verglas' in French, and merely an inconvenience. It comes and goes through the fall. However, if there's significant rain and a freeze then the trails become rivers of hard ice. This, alas, if fairly common in New England mountains. It means, primarily, that for hiking good 'traction' is needed to negotiate trails in the high country. This usually means crampons or good alternatives. I always carry a pair of light weight, strap-on crampons and wear the items in the photo below which are pull on. They have chains with hardened stainless steel cleats attached and offer a good enough purchase that you could use for some minor ice climbs. It's always good to have back up traction.

A month ago this was a much different scene. In a few days this could all melt, too, leaving the impression that it wasn't winter-like a few days past. To hikers who were on the mountain while the snow fell and the trail turned to ice it felt in every way like the dead of winter.

Here's where the tension began between the day's forecast and reality. It felt and looked like it was going to clear, or maybe it was just hope.

I was close to the ridge and the cloud cap should have dispersed leaving higher clouds scudding over the summit. And at moments it certainly looked as if the cap would tear itself apart and vaporize so that the summit would stand in the clear.

The reality was that this is as good as it got for the entire time I was on the mountain. It's certainly not terrible but after being spoiled recently by one or two brilliant days it's frustrating.

That's Lakes making a dramatic appearance as it emerges for a moment out of the clouds. At 5000 feet the air was several degrees colder even out of the 35 mph wind in the lee of the hut.

I left my pack at Lakes and climbed Monroe to keep warm and got into thicker and thicker fog. I went east on the Crawford Path to see and photograph the locations where the Dwarf cinquefoil, Potentilla Robbinsiana, plants were growing that I tracked through the summer. That bare spot in the photo is the small 'tarn' I had photos of in the blog several times during the summer.

Quite a bit of snow had bulked up on the leeward side of Monroe as well as in the trough made by the trail and in the krummholz.

The krummholz was icing as a result of precipitation and in this case it was most likely snow that had sublimated into ice or been turned to ice by the moisture in the wind. The ice builds gradually on the side of the plants towards the wind.

The Crawford Path

This is one location for several Robbinsiana's that grow close to the Crawford Path and outside the federally restricted area informally called Monroe Flats.

A close up of the lower right corner of the above photo shows the location of one of the Robbinsianas and it's not visible being an 'annual.' I was surpised that with the amount of snow the mountain received to date that the areas where the Robbinsiana is successful are not packed with snow throughout the winter season. The plants visible in the photo, some with red colored leaves, are Potentilla tridentata, or three toothed cinquefoil, a close relative of the Robbinsiana. There's also a leaf of Mountain Avens, Geum peckii, that has turned a pale orange color.

This is the nominal ground where you will find Robbinsiana. The tiny plant was all but wiped out of its precious niche here on Mt. Washington so that by 1984 there were less than 100 individual plants. Through a long, challenging collaborative effort the plant has been restored and has a large, thriving population at the moment. The biggest threat to the plant at the present time is the hard soles of hiking shoes on the feet of hikers who stray off the trails in the vicinity of where the plant grows.

Map lichen, Rhizocarpan geographicum, in a yellow mood. It stood out brightly against the dark, cloudy morning.

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