This week is the 17 year anniversary of the 2002 Denali Earthquake. At a magnitude of 7.9, to date, it is the largest quake I have personally experienced.
On 23 October 2002, the Denali Fault released a magnitude 6.7 quake. That would be a foreshock of what was to come on November 3.
Highway Shift; Richardson Highway, circa 2002
After the 6.7, I remember the Alaska Earthquake Center saying that the Denali Fault was capable of producing an 8.0. Sure enough, the fault came very close.
I was at an intersection in my ’66 Chevy C-20. All of a sudden, the truck was lurching all over the place, and I found it hard to stay on the brake pedal. There were two university students in the next lane, the passenger rolled down his window and asked what the hell was happening. I said, “Earthquake”. He then promptly hit the driver on the arm and said, “I told you it was an earthquake”.
The light changed, I drove on, but had to stop at the next light. The earth was still shaking. An elderly couple had been walking on the sidewalk, and the wife fell to the concrete, the husband was struggling to stay upright by hugging a signpost. Then the shaking was over. I rolled down the other window, to see if the couple was all right. They were, and I headed home to see if there was any damage.
The quake had ruptured 205 miles of earth along three different, yet connected faults in Interior Alaska. It was the largest ever recorded in Alaska’s Interior. It was the largest inland quake North America had seen in almost 150 years.
Both the Parks & Richardson Highways saw major damage. The Trans-Alaska Pipeline moved sideways 18 feet, and rose 5 feet. The engineers had designed for the fault, and the pipeline behaved exactly as it was designed to behave. Although, it did come within two feet of its sideways movement limit.
The Denali Earthquake was felt as far away as Louisiana.
Previously, the largest earthquake Fairbanks had experienced was a magnitude 7.3 in 1937.
It’s that time of year again. The aurora forecast from UAF’s Geophysical Institute is up and running again. A moderate aurora is being forecast for Thursday, with it being visible directly overhead for Fairbanks, weather permitting.
In Canada, Dawson City, Fort Nelson and Fort McMurray will find the northern lights directly overhead, assuming cloud cover doesn’t obscure viewing.
The aurora will be low on the horizon for Marquette, Michigan and Sundsvall, Sweden.
An equal, but opposite aurora will be taking place in the Southern Hemisphere, as well.
The Geophysical Institute at the University of Alaska – Fairbanks puts out their geomagnetic forecast daily.
It’s early August and people were starting to think “white stuff”. I had three jobs lined up, everyone desperate for me to start, yet not one of them was ready for me. What to do with the day off?
As luck would have it, Poker Flat Research Range had one of their summer walking tours that day, so I drove the 25 miles out to Chatanika.
“The Blockhouse” or bunker
PFRR is the world’s largest land-based rocket range. The facility is owned by the University of Alaska – Fairbanks. They launch sounding rockets from the range, in order to study the Earth’s atmosphere and the interaction between the atmosphere and the space environment.
Space junk returned to Earth
Study ranges from the Earth’s magnetic field to the aurora. NASA is prominent at the range, but researchers come from all over the world. All of the rockets launched from PFRR return to the Earth’s surface, and the range collects the spent payloads every summer. There is a reward paid out to anyone finding material from Poker Flat.
Poker Flat Launch Pad
The building above is open on the far end. The interior of the building, and the actual launch pad, was off limits to photography. It’s a NASA rule that doesn’t thrill UAF apparently, but we all honored the rule. The sounding rocket is brought in on what is basically an open trailer. The rocket is loaded onto the launcher, which looks like a giant erector set with a large pivot. The building itself is sitting on a pair of tracks. When ready to begin countdown, the building is pulled back away from the pad, and the rocket is spun vertical with the large erector set pivot.
The control center was surprisingly manual in operation. Scientists are extremely fussy about launch conditions, and they often pull the plug with one second to go. An automatic system does not give the flexibility that is needed, so there is still a “launch button”.
That doesn’t mean there is a shortage of cable, wires, or connectors.
The touring rocket
PFRR does a good job with the tour. It’s pretty relaxed, and a nice way to spend some time outdoors, for the most part, in an Interior Alaska summer. After the tour, don’t forget to stop by the Chatanika Lodge, which is just down the highway.
Recent paths of Arctic ice floes; Source credit: Thomas Krumpen, Alfred Wegener Institute; Institute of Environmental Physics, University of Bremen
Researchers from around the globe have congregated on Alaska’s Arctic coast. They are planning a once in a generation expedition into the heart of one of the harshest environments on Earth: The Arctic.
It’s a 12 month, 17 nation, 300 scientist effort aboard the German ice breaker Polarstern, to document climate change in the Arctic. This coming autumn, the Polarstern will be positioned in a remote part of the Siberian Arctic, and then wait to be frozen in the ice. The research vessel will then flow with the floe; traveling with the ice as it moves across the Arctic Ocean.
Only twice has a transpolar drift happened successfully in history. Norwegian explorer Fridtjof Nansen did it first in 1893. Ten years ago, a small sailing ship named the Tara also completed a transpolar drift without the sea ice crushing its hull.
NASA’s Goddard Space Flight Center, the National Science Foundation and universities from Alaska-Fairbanks to Oregon State to Dartmouth are involved. Most northern nations are playing a role, as well. Russia, China and Sweden have all committed ships and aircraft for resupply support. Japan and Switzerland have developed new research equipment especially for the expedition.
Unlike Antarctica, there is no land at the north pole to build a permanent research station. The RV Polarstern is the next best thing. At any one time, 60 people will be living and working on the ice breaker. Resupply will take place every 60 days, weather permitting. Researchers will also be swapped out during resupply runs.
Graph credit: National Snow & Ice Data Center
Time is running short for a expedition like this one. The key is to find old sea ice, 4-5 years old, and get locked into that. Since 1980, 95% of Arctic sea ice that is 4+ years old, has been lost. In the graph above, the lightest yellow is 1 year old ice, the dark purple 5+ years old.
It should be an interesting study, although researchers on board the ice breaker from December to February will not see the sun. They should see polar bears, however.
Alaska: 2018 Seismicity; Color coded by depth, Notable events labeled
The Alaska Earthquake Center at the University of Alaska – Fairbanks, has done their annual year in review for 2018. We set a record for earthquakes within the state, with over 55,000 events during 2018. That blows past the previous record of 42,989 set in 2017. The next highest number occurred in 2014 with 40,686 quakes. We had so many earthquakes in 2018 that AEC is still counting to get a specific number.
It needs to be noted, that much of the increase in numbers is due to advancing detection techniques, as well as additional recording stations. The purpose of this post, is not to imply that Alaska is about to break off from the Yukon, but to show how seismically active Alaska is.
The two largest earthquakes have set off thousands of aftershocks. The 7.9 magnitude quake in the Gulf of Alaska was the largest, followed by the now rated 7.1 near Anchorage in November.
We also had a couple of “swarms” in the northern part of the state, in the Brooks Range & on the North Slope, that lasted for months, and accounted for over 17,000 events.
The surprise earthquake of the year, happened near Kaktovik, on Alaska’s north coast. The 6.4 mainshock and 6.0 aftershock, were by far the largest ever recorded north of the Brooks Range.
On Saturday, March 9, a sudden jolt went through the cabin as I worked about the place, while listening to Minnesota hockey swarm the Michigan Wolverines. Sure enough, a 3.7 magnitude quake had occurred roughly 15-20 miles from the cabin.
A very special thanks to the Alaska Earthquake Center for the above graph and earthquake information.
The Poker Flat Research Range had its 50th Anniversary party over the weekend, and Fairbanks residents showed up in droves to celebrate. I think it is safe to say that Fairbanks is quite proud of its far-north launch facility. I was amazed at how many people came out for the event.
Owned by the University of Alaska-Fairbanks Geophysical Institute, Poker Flat is the world’s largest land-based rocket range. The 5132 acre site is located 30 miles from Fairbanks, just north of Chatanika, on the Steese Highway, where Poker Creek flows into the Chatanika River.
More than 300 major, high altitude rockets and 1800 meteorological rockets have been launched from Poker Flat to study the Earth’s atmosphere, and the interaction between that atmosphere and the space environment. The rockets launched are sounding rockets, which are designed to operate between the height that a weather ballon can reach, yet below satellites. Sounding rockets are relatively low cost, with a quick lead time, which is advantageous in the world of research.
NASA launches a sounding rocket at Poker Flat; Photo credit: PFRR
NASA, Wallops Flight Facility, the Department of Defense, and many universities world-wide, have launched rockets from Poker Flat.
A recovered payload from a March 2017 launch
One busy week at Poker Flat had four launches in 33 minutes during a night with high aurora activity. One mission saw two rockets launched to measure the turbulence in the upper atmosphere: was it two dimensional or three? Also measured were air density along the rocket’s parabola, which had an apex of 100 miles above northern Alaska. Also measured was the lowest reaches of where the aurora interacts with the upper atmosphere.
On the same night, two rockets from Clemson University launched. These rockets released a white vapor, trimethyl aluminum, so that researchers could visualize the turbulence 60 miles above the ground.
Not to be outdone, two nights later, a rocket launched for Utah State that released instruments to measure the voltages and currents in the aurora display over Kaktovik, Alaska.
Weather balloons ready to launch
I’m glad I arrived early, because I think turn out was greater than expected. After visiting the main offices, I walked down to where the shuttle busses were hauling people to the various sites. Poker Flat is fairly spread out, plus there was a cow moose and a calf wandering about, and officials seemed wary that someone could get stomped. Weather balloons were launched every 15 minutes or so, which I watched while waiting for a shuttle. Turns out there is an advantage to attending things like this solo. A University police officer offered rides to the upper facilities, and he had room for three. The first couple climbed in, and I seemed to be the only single paying attention, so I volunteered to climb in the back of the squad SUV.
Some NASA & PFRR “Rocketeers”
The facility is really quite impressive. I was able to talk to several NASA scientists, as well as some Poker Flat “rocketeers”. Everything was available to view, from the radar screens to the “catwalk” outside, and the green lidar beam, which is part laser and part radar, and is shot 50 miles into the sky. There wasn’t one person involved with the sounding rockets, that didn’t get excited talking about what they did, or what they had planned for next year. The representative from Wallops told me they were excited now to get down under to Australia to launch rockets next. It will be their winter soon, and they had some rockets designed that would open in the back with telescopes to get images of the southern sky.
A NASA launch as viewed by the Poker Flat Skycam; Image credit: PFRR
One thing about the aurora borealis that is not widely known, is that, due to the Earth’s magnetic field, what we see here in the northern hemisphere, the southern hemisphere sees the mirror image of. I have always found that fascinating.*
Early artwork of auroral display
The earliest written record of an auroral display was from 567 BC on a Babylonian clay tablet. The tablet describes a “red glow in the sky” lasting two hours. The red aurora was often thought of as an evil omen in medieval times. Nearly all northern native cultures associate the aurora with spirits of the dead.
Some statistics from PFRR:
First launch: March 1969
Heaviest rocket: Aries – 11 tons
Longest rocket: Black Brant XII – 85 feet
Heaviest payload: 2200 pounds
Highest altitude flown: 930 miles
Distance downrange: 1100 miles
Rocket acceleration: 17 Gs
Rocket speed: Mach 2
The view from a very bouncy squad SUV. The ride is not as comfortable as one might think.
The peak season for launches at Poker Flat is between January and March. Most often launches occur when the aurora is going, and the moon is down. Cleary Summit is a great place to watch and/or film a rocket launch. Poker Flat also streams launches live on its youtube channel.
The line for the shuttle bus, or the reason I took the police car; Image credit: PFRR
*See: Rockets Over Alaska: The Genesis of Poker Flat by Neil Davis
Located on the West Ridge of the University of Alaska campus in Fairbanks, is the Museum of the North. The museum takes on the daunting task of introducing visitors to the vastness and diversity, that is Alaska.
Otto the Brown Bear
“Otto” has been greeting visitors to the museum since its inception. He stands, all 8’9″ of him, at the opening of the Gallery of Alaska. The gallery is divided into the five main geographic regions of the state: Southeast, Southcentral, Interior, Western Arctic Coast and Southwest. Originally from Herendeen Bay on the Alaska Peninsula, Otto weighed 1250 pounds at the time of his death.
Woolly Mammoth skull, with mastodon and mammoth jaw
Locked in the permafrost, mammoth skulls have often been found by miners, as they worked the frozen ground for gold. Thirty-one, known, species of Pleistocene mammals roamed Alaska’s ancient grasslands with the mammoth.
Southeast Alaska totem pole
Petroglyph, Alaskan style
Blue Babe is probably my favorite exhibit at the museum. An extinct, mummified, steppe bison, that was discovered in the permafrost by placer miners in 1979. The bison died around 36,000 years ago, killed by an American Lion. The claw and tooth marks can still be seen on the carcass. Shortly after the kill, just before winter, the bison was covered by silt. It was then entombed in cold earth and frozen until excavated.
There are only two other discoveries from the permafrost, that have been reconstructed and put on display like Blue Babe. One a juvenile mammoth and the other an adult mammoth, both are at the Zoological Museum in Leningrad.
Even today, Blue Babe has an American Lion looking over its shoulder
The skull of an American Lion, with one of a saber-toothed cat above and to the left
The American Lion, now extinct, was around 25% larger than the modern lion. They roamed North America in the Pleistocene epoch, 340,000 – 11,000 years ago.
The Antler Throne
Kayak and open boat
The museum is open every day in the summer, and slightly shorter hours M-Sat in the winter. Admission is $14 for adults.
Cannons from the Russian occupation. Included solely for The Curator