Glacial karst: Descent into the Gornergletscher
The Gornergletscher is the second largest glacier system in the Alps, found on the western side of the Monte Rosa Massif flowing down towards the town of Zermatt. The glacier was the centre of interest for the Italian La Venta team during the 80’s and 90’s, during which time they found, explored and described a number of caves along its length. In August 2011, Martin Groves went out with a team to find and explore the moulins for himself, however the abundance of melt meant that some of the monster ones they found on the tail-end of the expedition were dangerously wet. Six weeks later, four of us returned in the hope that conditions were cold enough that water levels would be much lower.
The panorama above shows much of the length of the glacier and how the its surface is dissected by numerous canyons and gullies. Many of these terminate in deep shafts (moulins) through which much of the meltwater travels ultimately to the glacier terminus (pan the lower image for a more detailed view of the glacier).
Our camp was situated on the lateral moraine of the glacier (bottom left of panorama), amongst the rocky debris and below some dangerously loose cliffs. The views of the surrounding peaks, including the Matterhorn and Dufourspitze, however allayed any fears we had of getting crushed in the middle of the night.
The first moulin target was on the other side of the glacier, over an hours hike away at the end of a large gully draining from below the ice-fall of the Grenzgletscher. Although the weather was reasonably warm (<10ºC) the water running in the channel was minimal, which was great news for us. Between MadPhil and Martin, they rigged up the shaft and after a couple or re-belays got a fine drop down to the base some 26 m down. At the bottom obvious meandering passage led off down-glacier, but after 40 m or so deep water stopped us continuing any further. Up-glacier Martin and I took a soaking when we both fell through thin ice together into a waist-deep pool of freezing water. Although I escaped critical depth, Martin wasn’t so lucky. Pleased with our successes we called it a day there and made plans to return the next day to push on downstream, leaving the moulin shaft rigged ready.
Plans were thrown in the air when it started snowing that night. The promise of a front coming in by the locals materialised and over the next 30 hours we received nearly a foot of snow. A return to the moulin on the second day was obviously off the cards, so we spent it exploring canyons further down glacier from our camp hoping to find more potential moulins worth dropping. The shapes and scalloping of the ice channels were spectacular, and we all had a great time climbing in and around them.
As the front passed, the weather dramatically improved with the sun returning once again. We returned to our original moulin to find our kit engulfed, and our rigged ropes and ice-screws buried in ice. Martin went about recovering our kit with an ice axe and rigged up new rope to abseil on. At the base we were disappointed to find that the snowfall had made conditions somewhat wetter in the passage leading off. Without any way of drying our kit on the glacier we begrudgingly had to leave it there and prusik out again, MadPhil surveying on the way up and myself taking photos.
On our last full day on the ice, Martin wanted to revisit a couple of smaller moulins near camp; one with a sump in that could be potentially dived, and another (Ice Cube Mine) that had a number of short pitches. Although the sump was still open, just a few minutes walk away the bottom of the first pitch in the Ice Cube Mine was already sealing up preventing further progress.
We spent the next day carrying our many bags off the glacier to the railway station ~3 km away. Although we didn’t complete all the objectives Martin had planned due to the bad weather, it was a good learning experience for us all and conditions in the moulins looked potentially promising for a successful return trip to the Gornergletscher the same time next year.
Many thanks to Martin Groves for organising and inviting me along on the expedition. Also to MadPhil and John for being great company on the ice.