After a night in the sweat-box Windy Caboose we had breakfast, tidied up and made plans for the day. John, my partner on this trip had missed his last one and still (after being south a few times) had still not seen the Hinge zone on any of his trips. Hinge zone it was then!
We set off on the long journey that would take us back up to the base and then beyond. The route from windy to base is a well-travelled one and we were riding the doos un-roped. Once past base and away southwards towards the continent we stopped, harnesses up and roped all our sledges and skidoos together. This form of travel is a lot less relaxed for a few reasons.
Firstly you need to concentrate a lot more – you don’t want the rope too slack or it will be pointless (if a skidoo fell through into a crevasse it would fall further, meaning more shock-loading) or it can get tangled up in the skidoo itself. Too taut a rope and you end up getting a tow from the doo in front – pulling all that extra weight will quickly damage it. It’s a fine line between the two and you have to constantly match you speed to the doo in front, something that’s easy on a flat road, slightly harder on a sastrugi laden ice shelf.
The second reason this method of travel is not as relaxed is the actual reason we have to rope up – crevasses. Huge slots in the ice that can be covered over with just enough snow to be hidden, or be completely open yet still impossible to see until you’re right on top of them!
The first big feature you come to when travelling to the hinge zone is Gatekeeper. A known large crevasse with a section in the middle that narrows and has a very large and stable snow bridge across. Well, that was the last description of gatekeeper from the last visit there about five months ago. Things change!
We got within ten or twenty metres of where the crossing was, Al stopped and did a bit of a recce. I sat about twenty metres or so back and really couldn’t tell what he was looking at all. He turned back with a funny look on his face, waving his arms…
I roped up and walked down towards whatever Al was looking at, tied to a skidoo.
From the pic above you can tell that there’s not much to see right?
This was the view once I looked in. The photo is deceptive – this thing was deep! Also, the bottom is definitely not the bottom and could be just one of numerous false floors going down.
This is the view straight across, I couldn’t see any of this from less than ten metres away! The far crevasse is where the bridge used to be. This has now slumped in as the gap widened. Another slot has opened up in front leaving an island in the centre. The whole thing is a good fifty metres wide!
Above is the view to the right.
And to the left!
The photos just don’t look that impressive compared to the real thing. This whole feature was stretching out for kilometres making it virtually impassable.
Late last year Al had been down with one of the previous years wintering crew and abseiled down in to Gatekeeper. They had thrown in eighty metres of rope and still not even been able to see any bottom!
So sadly the Hinge was not to be for John. The whole area will have to be looked at in the summer and a new route found to get to the hinge.
We turned around (very carefully!) and set off back down towards the coast. Time was moving on and we decided to get back down to the creeks area, set up a base camp and venture out from there to other destinations.
Setting up camp takes a few hours and this then left us a bit of time to once again venture out onto the sea ice.
A small crevasse from the side (still big enough for a human to disappear and die in mind you). Small cracks can quickly turn into something the size of a valley given the forces that are acting on the ice – moving along at a rate of four hundred metres a year, with trillions of tonnes pushing it.
All this ice will of course break off when it reaches the calving face and any weakness or lines of stress in the ice will be right where it breaks. Sometimes this will lead to icebergs as big as small countries breaking off in one go – something that could well have left the old Halley V base floating away on a berg if a known fault line had actually split (this is one of the reasons BAS needed a new Halley). In other cases the ice might just get to the front and just break apart in small pieces and drop down on to the sea ice like a landslip or rockfall. Of course when I say small you have to bear in mind that some of the “little” blocks of ice that fall off will weigh thousands of tonnes!
The shelf ice breaking off in winter will fall down onto the sea ice. Some of the huge falls will then smash into the sea ice, either causing it to break and then reform or send out shock waves across it making huge cracks – like someone hitting safety glass with a hammer.
These cracks can be pretty big too. They can pull apart and re-freeze like this. Or, the ice can be smashed back together again Leaving great chunks sticking up.
Some of the ice though looks more like volcanic rock and seems to flow rather than fall into the sea ice.
Some areas look like they’ve been whipped up like ice cream.
or been chipped away an shaped with a giant chisel or adze.
Then there’s the merangue-like over-hangs (overhangues?) Some of these are thirty metres tall – made of just blown snow and ice sticking together. Sticking out quite a way from the cliff tops these must end up weight huge amounts, some of them actually look impossible – like that are defying gravity. ALthough they look quite fluffly when your trying to get through one from below when climbing, or trying to break one from above looking for a place to abseil they actually seem more like concrete!
And lastly of course…. more of the locals.
After a trip out eastwards on the sea ice we still had explore the west. And also fancied a trip to the Rumples!
That’s all coming up next in the winter trip sequel!!