National Fossil Day: A great time to dig fossils (both literally and figuratively).Courtesy Mark RyanNext month, the National Park Service once again teams with the American Geological Institute and other partners to celebrate the third annual National Fossil Day.

The mission of NFD is to “promote public awareness of fossils as well as to foster a greater appreciation of their scientific and educational value.”

This year the official day falls on October 17, but celebrations take place at various locations around the country over several days. Here at the Science Museum of Minnesota, the day will be celebrated on Saturday, October 20, 1pm-4pm throughout the museum. You can see what events are happening in your own area here.

Besides going out and hunting for fossils, one of my favorite NFD activities is the National Fossil Day Art & Photography Contest. As in previous years, the competition is open to anyone across several age groups. This year’s theme is “Careers in Paleontology”. A panel of NFD partners and paleontologists will select the winning entries. I’ve already sent in my submission but you have until October 5th (postmark deadline) to enter your own masterpiece.

National Fossil Day is usually observed in conjunction with Earth Science Week and this year is no different. EWS occurs October 14-20, and this year’s theme is Discovering Careers in the Earth Sciences.

LINKS
National Fossil Day website
Earth Science Week websie

Tags : Ameican Geological Institute, earth science, Earth Science Week, fossils, geology, National Fossil Day, National Parks Service, paleontology

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The Blue Heron: the Large Lakes Observatory's research vessel is owned by the University of Minnesota-Duluth.Courtesy Mark RyanLast October, I attended the Geological Society of America’s annual meeting held here in Minneapolis. The convention presented plenty of opportunities to hear the latest ideas in geology, paleontology, and planetary science but the highlight for me was being able to join a GSA field trip on Lake Superior aboard the research vessel, the Blue Heron.

Blue Heron interior: Mid-deck area includes monitoring station, right, and one of two dry labs, background left, serving as a snack table during our trip.Courtesy Mark RyanThe 86-foot vessel is owned by the University of Minnesota-Duluth (UMD) and operated by the Large Lakes Observatory (LLO), an organization created in 1994 for investigating the geochemical and geophysical properties of large lakes, and their global impact. To accomplish this research, the LLO required a worthy vessel for limnological research, and the Blue Heron was purchased just three years later.

The vessel docks at the Corps of Engineers Vessel Yard on Park Point (aka Minnesota Point), a natural sand bar separating Duluth’s harbor basin from Lake Superior. The ten-mile spit was created by the lake’s wave action on material deposited by the St. Louis river, and is supposedly the largest freshwater sand bar in the world. Field trip leaders Doug Ricketts, the marine superintendent at LLO, and Charlie Matsch, professor emeritus of geology at UMD, greeted arriving participants and divided us into two groups. While one group spent the morning on Lake Superior, the other visited geological highlights in the Duluth area with professor Matsch. In the afternoon the groups switched places.

I joined the morning shift on the lake with a dozen geologists made up of GSA attendees from Minnesota, Wisconsin, and City University of New York. Besides Doug Ricketts and the ship’s five crew members, regents professor Tom Johnson, and the director of the LLO, professor Steve Colman, were also on hand to help demonstrate and explain the Blue Heron’s research capabilities.
Lakebound through the harbor: As we head toward Lake Superior, regents professor Tom Johnson, left, and director of the LLO, professor Steve Colman, discuss the morning agenda with one of the field trip passengers. The yellow tow fish used for profiling the lake bottom sets on the deck in the background.Courtesy Mark Ryan

Safety first: Blue Heron chief mate, John Simenson, goes over some of the vessel's safety rules.Courtesy Mark RyanWe shoved off right on schedule, heading across the harbor toward the Superior entrance on the Wisconsin end of the sand bar. The crew spent this time going over the ship’s safety rules - how to descend ladders, which alarms meant what, how to communicate with the bridge - that sort of thing. We then made a quick tour of the facilities. The Blue Heron is equipped with a wet lab on the open deck and two dry labs inside, and all sorts of data gathering equipment for geophysical, geochemical, and biological sampling. These include multibeam sonar for profiling the lake bottom and sub-bottom, several coring instruments for collecting sediment samples, and water samplers able to collect at various depth levels in the water column while also measuring such things as temperature, depth, pH levels, and conductivity. There’s gear for tracking lake currents, and plankton nets and a trawl for gathering biological data. Inside, both above and below deck, computers record, display and analyze the gathered data. Many of the off-ship instruments can be monitored and controlled on-board from computer consoles.

Out on the big lake: Lake Superior is the deepest and largest of the Great Lakes, and contains ten percent of the world's fresh surface water.Courtesy Mark RyanThe R/V Blue Heron is outfitted to carry five crew members and six researchers and can stay on the lake, around the clock, for 21 days between port calls. It’s used mainly on Lake Superior, the largest and least studied of the Great Lakes. Shipboard amenities are sparse (there’s no television or DVD) but include eleven bunks, a full galley for food preparation, dining table, shower, and of course, the "head", or as you landlubbers like to call it, the toilet. Internet service is sometimes available when the vessel is near shore.

Yellow fish deployed: The EdgeTech CHIRP/sidescan sonar is submerged and towed behind the Blue Heron for gathering bottom data.Courtesy Mark RyanUpon entering Lake Superior, the crew set to work demonstrating some of the vessel’s science gear, which is pretty much the same kind of instrumentation used in oceanographic research. Just beyond the Superior entrance, the EchoTech CHIRP/sidescan sonar tow fish was lowered from the Blue Heron’s stern. This bright yellow instrument is towed underwater behind the vessel as it makes several passes over the lake bed, and able to gather hydrographic and bathymetric data. One function is to send out an intermittent, low frequency “chirp” pulse that can penetrate the sub-bottom and record changes in its geophysical properties. The sonar data is processed using on-deck computers.The first demonstration was a scan of the underwater channel of the Nemadji River, a Wisconsin tributary to the lake. The mouth of the Nemadji has been drowned by a process called post-glacial rebound or more scientifically, differential isostatic rebound. During the last ice age, a mile thick sheet of ice covered the region and placed enormous pressure on the earth’s crust, depressing it downward. As the glaciers retreated, that enormous weight was gradually removed, and the lake basin began to rebound (a process still going on today). But the northern and eastern ends of Lake Superior basin are rebounding at a faster rate, tilting the water southward and to the west and subsequently flooding those areas of the shoreline.

CHIRP/sidescan sonar monitors: Left display shows a sidescan view of the bottom. Right monitor reveals CHIRP sub-bottom profile of drowned channel of the Nemadji river.Courtesy Mark RyanAs the submerged tow fish was doing its stuff, we all gathered at a couple workstations in the lower deck dry lab to watch as images appeared on the computer screens. In one, you could plainly see the distinct profile of the Nemadji’s drowned riverbanks.
Lower deck dry lab: Marine superintendent Doug Ricketts explains the R/V Blue Heron's data gathering capabilities to field trip participants.Courtesy Mark RyanThe other monitor displayed bathymetric information being picked up by the duel frequency sidescan sonar. Printouts of the lakebed topography, created from a mosaic of stitched-together scans, were laid out on a worktable with several charts and maps.

Yellow tow fish retrieval: Blue Heron marine technician Jason Agnich (left) and seaman Peter Norick haul in the EdgeTech sidescan sonar tow fish.Courtesy Mark RyanFor the next demonstrations, the Blue Heron moved out several miles onto the big lake. We’d all been warned of the lake’s fickle weather, and told to bring proper attire, just in case. Having been raised in Duluth, I was well acquainted with Superior’s moodiness, especially in autumn, so I brought along rain gear, a jacket, and an extra sweatshirt, expecting the worst. But I was most comfortable in jeans and a t-shirt. Cloud cover was sporadic, and while the water temperature was only around 49 degrees, the air temperature hovered in the mid to upper 70s during the entire excursion. We couldn’t have hoped for a nicer day; a perfect Duluth day, as we used to call them.

While some of the group watched the crew prepare for the next presentation, others enjoyed lunch (sandwich, chips, fruit and a cookie) at the galley dining table. During my lunch break Tom Johnson told me the story of how the university came to own the research vessel. In her previous life, the Blue Heron was known as the Fairtry a commercial fishing trawler that fished the Grand Banks in the northwest Atlantic (like the Andrea Gail in The Perfect Storm). UMD purchased it in 1997 and Tom sailed it from Portland, Maine, through the St. Lawrence Seaway and across the Great Lakes to Duluth. Despite some minor engine problems at the start, he said it was a fantastic two-and-a-half week trip. Over the next winter, the Fairtry was converted into a limnological research vessel and re-christened the Blue Heron.

Water sampling carousel: GSA field trip participants listen as LLO's Doug Ricketts, center, goes over some of the geophysical and geochemical data gathered by the Blue Heron's water sampling carousel.Courtesy Mark RyanMeanwhile, out on the back deck, the crew was ready to launch the next instrument, a carousel of canisters called Niskin bottles used for sampling the water column.
Topside control: Marine tech Jason monitors the submerged water sampling carousel, which can be controlled to collect water samples at different levels, as well as additional water quality data.Courtesy Mark RyanThis device is lowered into the lake and controlled remotely from the deck, and can collect samples at various depths into any one of its dozen canisters. It can also measure temperature, conductivity, pH balance, transparency, dissolved oxygen levels and other tests. After deployment, marine technician, Jason Agnich, sat at a computer workstation just inside the hatch, and easily controlled the carousel with a joystick while monitoring its progress on a couple electronic displays.

Gravity corer: Marine technician Jason Agnich helps launch the gravity corer, retrieves the sample, and lays it out on the wet lab workbench for study.Courtesy Mark RyanWe moved a little farther down lake where two coring instruments, a spider-framed multi-corer, and an arrow-like gravity corer were put into action. The first can collect several shallow core samples by lowering it by winch to the lakebed, while the latter is dropped like a giant dart deep into the sub-bottom sediment for one large core.

Sediment sample examination: Tom Johnson, left, and Steve Colman examine one of the sediment samples collected by the Blue Heron's multi-corer from the bottom of Lake Superior.Courtesy Mark RyanAfter each was raised back to the surface, the collected core samples were removed from their tubing and laid out on the wet lab table for study. We all huddled around the workbench as each core was cut open with a knife so participants could take a closer look. The sediment cores were composed of a densely packed fine-grained mucky silt as brown as milk chocolate, and appeared more appropriate for a scatological study than a geological one, to me anyway. But that didn’t stop some of us from taking home a small plastic bag of it as a souvenir.

View of the Blue Heron's wet lab: Lake bottom sediment samples are examined on the workbench.Courtesy Mark Ryan
View from the Blue Heron: As the research vessel heads back to port, autumn colors brighten up Duluth's distant hillside.Courtesy Mark RyanAs we made our way back toward the harbor, I stood at the starboard rail and took in the beautiful autumn colors lighting up the lake’s distant North Shore. We were three, maybe four miles offshore but I was able to pick out my old stomping grounds in Duluth’s east end. The old neighborhood – like much of the city - was built up on terraces formed by past shoreline configurations of prehistoric Lake Superior. Duluth’s Skyline Parkway, a boulevard that skirts the hilltop across the length of the city was built on an old gravel beach line of Glacial Lake Duluth when the water surface was nearly five hundred feet above its present level. The bridge over the mouth of the Lester River was just barely discernible from where I stood but it was easy to spot the large swath of dark pine forest that encompassed Lester Park and Amity creek (the western branch of Lester river) where my friends and I used to hang out. It’s also where Charlie Matsch would guide our group later in the afternoon. He brought us there to examine the Deeps, my favorite old swimming hole carved out of the massive basalt flows that extruded from what’s now the center of Lake Superior during the Mid-continental rifting event that took place nearly a billion years ago.

Harbor bound: The Blue Heron heads back to port through the Duluth canal.Courtesy Mark RyanWe returned to port through the Duluth entrance, and as we entered the canal captain Mike King announced our arrival with a blast of the Blue Heron’s air horn. Duluth’s landmark Aerial-Lift Bridge, already raised for our return entry, responded in kind with a shrill loud blast of its own. Tourists lining the pier called out and waved as we passed the old lighthouse and rolled toward the harbor. We all waved back and I have to say it was kind of a thrill, for me anyway, after having participated in the same ritual, oh probably a hundred times in the past but always from the pier not from a vessel.

Return to harbor: The Blue Heron heads back to port after passing under Duluth's landmark Aerial-Lift Bridge.Courtesy Mark RyanThe Blue Heron swung in through the harbor, and soon we were back at port where we started at the Corps of Engineers Vessel Yard. Charlie Matsch was there to greet us and take for the second leg of the field trip.

Charlie took us first up the hillside to the rocky knob near the landmark memorial Enger Tower where he showed us some interesting exposures of gabbro, an intrusive rock common to the geological formation known as the Duluth Complex. Much of the bluffs west of downtown Duluth are composed of this dark, course-grained mafic rock. Now, I admit I enjoy a geological outcrop as much as the next guy (especially when a real geologist is explaining it), but it was the sweeping view from the hilltop that drew my attention.
The Blue Heron: cuts through Duluth's harbor for another excursion on Lake Superior.Courtesy Mark RyanThe lake and harbor and much of the St. Louis river bay stretched out below us in an array of vivid blues contrasting with the bright reds and golds of autumn. On one side of the harbor, bridges, railroads, and structures of industry jutted out on Rice's Point toward Wisconsin, paralleled on the other side by the slender ribbon of Park Point. As I took in this grand vista, a small, barely discernible bluish blur of movement caught my eye. There, cutting through the harbor, the Blue Heron headed southward toward the Superior entrance for another run on the great lake.

More photos on Flickr
More about Blue Heron
Lake Superior facts
Lake Superior video

Tags : Blue Heron, earth science, geology, glacial lakes, global climate change, Great Lakes, hydrology, Lake Superior, Large Lakes Observatory, limnology, research vessel, UMD, University of Minnesota-Duluth

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‘Climate change’…we just can’t get away from it these days. Carbon everywhere, rising ocean levels, floods, droughts, and never-ending ‘Seinfeld’ reruns…make it stop! To us regular folks though, the evidence isn't really seen in the day-to-day. So as Jerry would say, ”What’s the deal?”
Just like castles made of sand: USGS researcher Ben Jones measuring AK coastal erosion on the Beaufort Sea.Courtesy Christopher Arp, USGS

Well skeptics, read on. According to researchers with the Institute of Arctic and Alpine Research (INSTAAR) at the University of Colorado, parts of the US are literally falling into the sea due to factors associated with climate change. Sure, coastal erosion happens, but this is getting ridiculous.

How do they know? Over two years, a team of researchers from CU and USGS used weather stations, GPS data, wave intensity/water temperature sensors, and time-lapse cameras to record coastal erosion between Point Borrow and Prudhoe Bay, Alaska during the summer months when the sea ice is out. In these videos, you can watch the coast crumble to the sea. That's right, you can actually see the Alaskan coast fall apart before your eyes! (watch the video)

Affected coastline: Alaska's endangered coast, with Beaufort Sea to the North.Courtesy Goodle Maps, edited by Prescott Esquire
Why is this a big deal? It used to be that this coast would lose a handful of yards each year during the short summer season, but more recently, this coast is falling apart on the order of 30-45 feet annually. That means that between the time INSTAAR started looking at this problem and today, the coast has lost almost the length of a whole football field! And, according to the video linked above, that’s valuable real estate for migrating birds and other critters. In addition to habitat loss, think about it: our country, the US, literally falling apart. Lame.

How is this all going down? The biggest factor is the coast itself. The soil is usually 50-80% ice; the rest is silt and mossy plant material. Now, imagine a brick building where all the mortar (stuff between the bricks) melts away and you have an idea of what happens to this soil when summer heats up.
But it’s more than that: Robert Anderson, researcher with INSTAAR and CU Geographic guru tells us that there is a TRIPLE-WHAMMY at play where each ‘whammy’ works together towards coastal carnage.

Whammy 1: Longer the ice is away, the more soil melting occurs (more melting=more destruction).

Whammy 2: Longer the sea ice is away, the warmer the ocean gets (up to 60ºF, warmest temp. on record…ever).

Whammy 3: Further back the ice melts, the bigger the waves can get (called the “fetch effect”).

More stuff: The buzz on this one is crazy, just Google “Alaskan coastal erosion”. USGS did a study up there in 2007 (USGS article), Nat Geo has got another video, even Reuters is on this story. Anderson’s paper is still pending, but the researchers have presented these findings at annual American Geophysical Union meetings in ‘08 and ’09 (abstract). Check it out and let me know what you think.

Tags : climate change, Earth Buzz, earth science, geography, USGS

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