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October 28, 2022
What lives in frozen soil for 25,000 years?
In October 2022, Josephine Galipon visited Alaska to see if she could tease out genetic information from gray cylinders of permafrost — silty soil that has been frozen for at least two years, but in this case thousands.
October 14, 2022
Grains of Alaska made into art
Kelsey Aho works as a mapmaker for the U.S. Forest Service in Alaska. She is also an artist who collects earthen materials on her travels around the state. Throughout Alaska, Aho has gathered mineral soils — including clays when she can find them — as well as ash. She has collected from, among other places, the Denali Highway, Hartney Bay near Cordova, the Chilkat River and Murphy Dome in Fairbanks.
January 31, 2022
Thirty years on semi-solid ground
At the end of this month, Vladimir Romanovsky will retire after 30 years as a professor and permafrost scientist at the University of Alaska Fairbanks’ Geophysical Institute. This comes at a time when people — finally — no longer squint at him with a puzzled look when he mentions what he studies.
June 22, 2021
Low-displacement landslides explain unusual West Virginia landscape features visible in lidar imagery
Like so many older landslides in the Appalachians, the significance and cause of these features is unknown. Because they are so numerous and are only visible using lidar data acquired in 2016, they may represent an untapped resource of useful information about the recent history of Appalachian landscapes.
April 16, 2021
Listening to avalanches half a state away
High on the broken pyramid of Iliamna Volcano, rotten rock held in place by volcano-warmed ice sometimes loses its grip. Several times over the years, rock-and-ice avalanches have blasted down Iliamna at 150 miles per hour. Left behind on the mountain’s face is a dirty, five-mile scar, in the same place as the last one.
April 6, 2021
Central peak formation in model impact craters
I produced the model impact crater with a combination of the same granular materials I use for tectonic models and a projectile fired from a powerful air rifle (a city-safe version of Gene Shoemaker’s approach). The model crater developed a nice central peak as well as terraced margins. The darker material is quartz sand, combined with a small amount of cornmeal to produce a minor amount of cohesion between sand grains. The white material comprising the central peak is glass microbeads.
March 24, 2021
What does that landslide actually look like, part 2: an active landslide
As indicated in the previous post, lidar-derived imagery still needs ground-truthing to maximize its usefulness as a means of characterizing landslides and other slope failures. Last June, Ken Gillon and I visited the Rutherford County, North Carolina, landslide described below as part of our work with Appalachian Landslide Consultants, PLLC (ALC) on behalf of the North Carolina Geological Survey. This slide caught my eye in lidar hillshade imagery because it appeared to share characteristics with an active slide we had visited a few days before.
March 4, 2021
Finding the great earthquake of 1900
The largest earthquake on the planet for the year 1900 happened somewhere near Kodiak, Alaska, on Oct. 9. Scientists know it was big, but how big? And could it happen again?
March 1, 2021
What does that landslide actually look like?
We have no constraints on the age of the slides, but they may reflect logging history in the area. The majority of these slopes were heavily and continuously logged during the past ~150 years, with logging in this area clearly occurring within the past 50 years. The slides may have developed after clear-cuts, with the rapid return of vegetation common in the region quickly making the area look less disturbed than it really is.
Malaspina Glacier gets up and goes
Massive icefields near the Canada/Alaska border feed Malaspina ice through a slot in the mountains. Freed of mountain walls, Malaspina’s ice oozes over the coastal plain like batter on a hot griddle. Near the Gulf of Alaska about 30 miles northwest of Yakutat, the glacier is — on clear days — visible from a window seat on an Alaska Airlines flight from Southeast Alaska to Anchorage. But the dirty-white blob on the cheek of Alaska is not as large as it used to be, which is why glaciologist Martin Truffer and his colleagues are studying it.
