Tunnel Ridge And Mercury Min

Les conditions de neige étaient :

• Croûtée
• Lourde

Nous avons parcouru:

• Forêt dense

Nous sommes restés à l'écart de:

• Pentes convexes
• Pentes raides
• Pentes ensoleillées

La journée était:

• Nuageuse
• Chaude

We skinned up the Sunnyside trees from tunnel creek hut at 8am and observed a large wet loose debris slide that seemed to come from a single point potentially dropped off a tree on slide side path.

We approached the ridge and looked into mercury basin which had further evidence of natural wet loose debris and big pin wheel debris.

The snow felt heavy and wet in sun affected areas which turned to a crust layer when out of the sun. The softest snow was found directly under the trees.

We dug a pit on the west facing slope of tunnel ridge which faced into mercury bowl. The snow pack depth was 250cm at this point.

The snowpack clearly showed the heavy wet recent storm slab snow of 50cm sitting on a ice hard pack for the lower section of the snow pack. The interface between the two sections had a layer of groupal polystyrene ball type snow.

We performed two propagation tests, the first showed no weak layer instability.this was performed across the full 90cm wide column.

The second was performed on a smaller isolated column. This test showed the interface between the new storm snow and the hardback below failed at around 28 CP (new to pit tests - , but I understand this to be 10 with wrist,10 with forearm and 8 with shoulders).

The slope was around 25-30deg,

1900m elevation.

We skied in the trees of mercury basin and saw no new avalanches but often large pin wheels or heavy slabs of snowpack break off. The skiing was still very fun, great last hut trip to finish off my first season in the backcountry.