Glide crack

Can anybody identify where the glide crack slope is on this map? I think it is the slope NW of the word "GRADE" along the old rail line.

<br><br>Yup, I think that's right.<br><br> x marks the spot

I noticed this feature the last few days and I would like to offer up another possibility. I do not believe that faceting or TG had anything to do with this avalanche. <br><br>To me it looks just as likely that the failure may have occurred within a thin layer of soil. The desciption by those in earlier threads of this area having a thin layer of soil and heather over smooth bedrock would suggest to me that moisture trapped between that bedrock and soil would create a very unstable situation. When the crack opened up, it was clear that the whole snow pack had separated from its base. (I saw a clean black surface and this is also seen in the crack area in the photos.) What is not clear is if the snow slab had a layer of soil(mud) sticking to its bottom. I would bet it did.<br><br>In the Cascades, early heavy snowfalls insulate the soils beneath very efficiently and I would guess that often the soils remain unfrozen. Even if soil freezing were to occur, it would not be at great depth. Any if you have ever seen the interface between frozen soil and soggy thawed soil you have seen grease on a wheel!<br><br>Even with those coldest days of the year, the strong sun each day likely penetrated that solar-panel of a slope such that it warmed at depth. The snow pack itself probably preserved that warmth at night only to refresh the heat the next day. This feature really started and released AFTER the stong cold winds had subsided, but the days still were sunny and warming.<br><br>That the other slopes in the area also did not suffer the same fate to me is likely due to the other factors listed by other posters, including an aspect that tends to accumulate water. But don't forget the fact that this slope had suffered climax released often and the soils do not have a stabilizing "old growth" heather and scrub layer on top.<br><br>I have looked at climax avalanches in the North Cascades where it seemed to me that most of the damage to the soil and vegetation occurred well below the fracture zone once the release really got moving. Here it seems just the opposite, with the deepest penetration into the soil having occurred even before the release.<br><br>In any case I think that this possibility would explain what otherwise looks very counterintuitive given what we know about avalanches. One other point in favor of this idea is that I have noted essentially no other avalanches occurring on any of the other slopes of similar aspects.

In support of those pushing the deep layer TG theory, I would not give up on that as being a contributing factor because of the pervieved depth of the snowpack at Stevens this year. While the protected areas at the pass are pretty deep, those slopes facing south do not have that much snow. From what I can see that fracture is not all that deep. These slopes are fully exposed to insolation, and having been up at Stevens every single week since the beginning of skiing this year, I can tell you that while the snow was piling up on the flats and the north facing slopes, those south facing slopes took much longer to fill in. Every day of sun and/or brightly lit cloudy days have been eating at those slopes.<br><br>So if there is only 4-5ft of snowpack on a relatively warm ground, then those cold nights were ideal for moving water vapor from the warm ground/snow interface up closer to the sub-zero surface. (But until someone gets up there to prove that, then I will still stick to my mud model!)<br><br>Alan

I still like my mysterious geothermal heat theory... though it's the most unlikely, it is the coolest <br>(and not completely impossible, given the hot springs across the road).