Members of the Wooster Tree Ring Lab had a great opportunity to travel to a seldom-visited part of Glacier Bay National Park and Preserve – a transect from Wolf Lake to Burroughs Glacier. We were there because there is 2500 year-old forest remnant that was overrun by ice. The ice has gone and continues to melt. Our interest is recovering these logs is to fill a gap millennial-scale tree-ring record from the Gulf of Alaska. The recently exposed logs are being lost to science each year as they flush out into the sea and rot away in this hypermaritime climate. Wooster student independent studies (ISs) in the region quite literally have surrounded this Wolf Lake site with their research, and over the last 10 years we have honed into this key location from all directions.
A view of Mount Wright through a gap in drift and bedrock. Tree-ring records from the flanks of Mt. Wright were part of a study led by Stephanie Jarvis and sampled by Sarah Appleton, who did their thesis work in the region.
We flew into the site this year. In previous years we attempted to walk in twice and once we were successful. I recommend the flying in – the brush and terrain makes it a brutal walk from Muir Inlet. Previous students Willy Nelson, Zach Downes, Dan Misinay, Jeff Gunderson, Andrew Wayrynen and Jesse Wiles were some of those that would have appreciated a float plane ride into the lake.
Nick Wiesenberg at the head of a fan on Minnesota Ridge – in the distance is the blue of Wolf Lake and beyond is Muir Inlet. The ice covered this entire scene 100 years ago.
The flight over from Juneau afforded excellent views of Casement Glacier where students Sarah Appleton and Joe Wilch worked.
Below is the sediment-charged plume from Casement Glacier as the Casement River empties out into Adams Inlet. IS students Jenn Horton and Lauren Vargo and I paddled through these waters on our way into the Inlet a some years ago.
Back to the Wolf Lake Basin – the upper reaches of the river and the pass (Glacier Pass) that we used to get to the Burroughs Glacier Basin.
We were there for the logs and here Nick is sneaking up on a potential sample.
The fans were more like rock glaciers and frankly we do not really understand these systems that are less than 100 years old.
I have to give credit to Nick for his tenacity and drive in systematically covering these fan surfaces and sampling the best hemlock logs we could find. This maps shows the sample sites – they are disperse across the landscape, but the logs are there and they cannot hide for long.
Nick coring a log beneath a snow bridge at the head of a fan.
The samples in the upper right portion of the map are taken from the flanks of the remnant Burroughs Glacier (named after the NY naturalist John Burroughs) who was a friend of John Muir and a member of the Harriman Expediti0n. At least five dissertations were written by glacial sedimentologists who studied ice-contact deposition along the margins of Burroughs – they include researchers from The Ohio State University, the University of Wisconsin – Madison and Michigan State. Wooster students Sarah Appleton, Andy Nash and Abby Vanlueven all worked in the area just south of Burroughs.
Nick standing on the dead ice of Burroughs Glacier. Below he takes a core from a unsuspecting log.
The granite in the area preserves dome nice glacial features – here a bullet-shaped boulder complete with a striated surface and a plucked (right side) end.
Must be some kind of bits of host rock (dark clasts) incorporated in a magma.
We are lucky to be collaborating on this project with others on this project from the University of Alaska – Fairbanks and the Park Service. Dr. Ben Gaglioti worked earlier in the summer at another location along Glacier Bay’s wild outer coast – his work was written up in a 3-part series by Alaska Science writer Ned Rozell in the Juneau Empire, here, here and here. This project was funded by the National Science Foundation Paleoclimate Program (Awards: P2C2-2002561 and 2002454).