Sky Pilot Col: Where Igneous Meets Metamorphic Rock

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Source: USGS, full map here.

More specifically, where Cathedral Peak granodiorite (pink; 86 million years old) meets Jurassic (light green)/Triassic (dark green) metavolcanic rock (150-250 million years).

We hit Sky Pilot Col at sunrise, left camp at 4 am. Had 3 passes to hit today and we’d be back in Twin Lake by late afternoon. On the other side of Sky Pilot Col is a zone of geologic convergence (*I am not a geologist). It actually made for somewhat pleasant talus walking. The shattered volcanic rock would fill in the gaps of the granite boulders. Instead of skiing down volcanic scree, or falling into crevices between granite boulders, we finally found perfect talus on the last day of Roper’s route.

Below is the view looking south from Shepherd Lake. Volcanic on the left, granite on the right. The surficial deposit just above the lake is dated to the Holocene (~12,000 years ago) or just after the last glacial period. That glacier took a little bit of metamorphic talus and a little bit of granodiorite talus, blended it all up, then dropped it here for us to walk down.

What is the difference between granite and granodiorite? Well… It’s very similar to granite, except it has more plagioclase than orthoclase feldspar… In other words: granite with black spots in it(?). Moonstone is mostly orthoclase.

andrew batjiaka

Sierra High Route 2016

Sierra High Route Pt 2

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Day 3 Mileage 8-9

Certainly an eventful day. Up at 5:20, hitting pass around 6 am. Dropped down into basin between Cirque and Potluck at ~9 am.

On the way down we saw two people hanging out by the lake. When we got down there a woman came up to us and said her hiking partner had bad altitude sickness. At first we thought it may have just been AMS, until we saw him and saw how advanced his symptoms of HAPE were. He was in very very bad shape.

We went through the options with them, either up at over class 2-3 Cirque pass to drop back down to the JMT around 8,000 feet. Or back the way they came over class 2-3 Potluck And Knapsack. Or to climb down Glacier Creek which looked steeper than either pass on our topo. We were at 12,000 feet and needed to get him down to 8,000 to try to alleviate his symptoms.

He really did not look good when we first saw him. He said he couldn’t even walk 10 feet. Nathaniel had all the symptoms of high altitude pulmonary edema – gurgling, short breath, coughing fluid/foam, felt liquid in his lungs. I looked nigh impossible to get him out of this basin on our own. Nate said he wanted us to active the SPOT plb. I hit the SOS button at 9:33 am. It was a waiting game now.

Looking back at Cirque Pass.

Looking at Knapsack pass.

Glacier Creek.

After a while, everyone was pretty silent – aside from checking in on Nathaniel. I knew this could take a significant amount of time. There was a chance we’d be spending the night there – waiting and not knowing if help was coming. About 2 hours later another group comes over Knapsack pass. I’m relieved to hear they have a Delorme. We’re able to text out to Mom that we’re okay, and send a more detailed message to SAR. Turns out at this point they’d already been dispatched.

I strained my hearing for any hint of helicopter – not knowing if help was 15 minutes away or 15 hours. Thankfully we only had to wait for 4 hours as we heard a helicopter at 1:30

The medic gave Nathaniel a bunch of drugs and walked him over to the heli – he could only go 5 paces at a time.

Very relieved that SAR was able to get Nate out so quickly, SPOT to arrival was 4 hours.

We start ascending again at 3 pm.

Camp is on the Bishop pass trail tonight.

Day 4 – 21 miles

Well shit, did I mention we only did 9 miles yesterday? It’s a blessing in disguise, I’m not so intent on hitting our mileage now that we’re so far off schedule. Flexibility!

Muir Pass today. See tons of JMT hikers.