Courtesy Mark RyanBirds seem to be a big part of my recent experience, so I thought I'd put together a little post of events featuring our fine, feathered friends.
Here at the Science Museum of Minnesota, an antique model of Archaeopteryx originally created by modelmaker Gustaf Sundstrom in 1934 is on display once again as Object of the Month for October.
Courtesy Mark RyanArchaeopteryx has long been considered the earliest bird - it lived around 150 million years ago during the Late Jurassic - sharing the world with giant sauropods and vicious therapods such as Apatosaurus and Allosaurus, respectively. Even though Archaeopteryx has been recently re-categorized from being a "dinosaur-like bird" to being a "bird-like dinosaur" (I'm not sure what the difference is but I suspect it has do do with percentages) - anyway, it still ranks as one of the great transitional fossils. You can see the Object of the Month display in the Collections Gallery on the 4th floor of the Science Museum of Minnesota all this month.
Another bird-related story deals with naturalist and artist John James Audubon and his artistic masterpiece Birds of America, both which I've covered before here.
Courtesy Mark RyanBack in the early 19th century Audubon, tramped around the American frontier seeking just about every kind of bird he could find, shoot, and paint for his masterpiece natural history tome, Birds of America. The original edition featured 435 exquisite plates of birds drawn in natural size, were etched in copperplates (along with some engraving and aquatint), then printed in black and white and printed on large double-elephant folio-sized (30 x 40) handmade paper. Each of the large black and white prints were hand-painted in watercolors by a team of skilled colorists and bound into two volumes. Long considered one of the greatest collections of natural history illustration, only some 200 sets were completed in the mid-19th century. Of those only about 100 remain in existence. The rest were either destroyed or disassembled and sold off as individual prints. Because they were hand-colored, these large first editions are considered "originals" and are quite valuable. Smaller, more inexpensive prints and editions were later created and sold.
Courtesy Mark RyanLucky for us one of the original Double Elephant Folio sets is held by the Bell Museum of Natural History in Minneapolis. Even luckier for us, the Bell has just opened a brand new exhibit, called Audubon and the Art of Birds, which is centered around some of these beautiful originals of Audubon's wonderful illustrations. I attended the preview a couple weeks back and let me tell you, it is a chance in a lifetime to see these rare and beautiful natural history illustration masterpieces. The exhibition opened on October 5th and runs in two sections. Right now, 33 of Audubon's mammoth prints grace the walls of the exhibit (along with illustrations by other bird artists) then other restored mammoth prints of Audubon illustrations will be rotated in during a two week shutdown in January, and the exhibit's second half reopens on February 1st. Find more information about the exhibition here.
Courtesy Mark RyanLast week, my wife and I took a day-trip to Duluth and stopped at Hawk Ridge Bird Observatory, located on Skyline Parkway overlooking the east end of the city. The site is a favorite autumn destination for bird-watchers of all kinds.
Courtesy Mark RyanOfficial bird-counters were still there tabulating hawks, eagles and other raptors migrating south for the winter. The count will continue through October.
Courtesy Mark RyanThe birds don't like crossing the wide expanse of Lake Superior on their way south, so they funnel into Duluth to cross there. We only saw a couple birds in the air while we were there (some 680 had been counted earlier in the day), but a couple of hawks snared just down the road were brought up to the ridge overlook for banding and release. Volunteers tagged and recorded the hawks (a goshawk - Accipiter gentilis - and a sharp-shinned hawk - Accipiter striatus), then enlisted the help of a couple of lucky onlookers to release them back into the wild. It was a beautiful afternoon on the Ridge.
Courtesy AmandaDid you know that artifacts must be cleaned once they are taken from an archeological site? Every category of artifact must be cleaned in a different way, as to prevent damage. Lithics (stoneworks) can be scrubbed vigorously and can be soaked with water unless it has a worked edge which may have residue that can be identified. Pottery should be scrubbed less vigorously and cannot be submerged, as the pottery would absorb the water and disintegrate. If pottery is larger than a quarter, it should not be scrubbed on the interior, as it may have some residue that would be helpful. Faunal (bone) artifacts must be cleaned very carefully, like pottery, or it will become soft and brittle. Charcoal contains certain carbon isotopes, like carbon-14, that we can use to date when the item was burned, allowing us to learn a lot from small artifacts. Charcoal also preserves anything living, like seeds or wood. Artifacts are scrubbed with a wet toothbrush and put on a newspaper to dry. Once the artifacts are dried they are cataloged and put in the collection for research.
Last Monday, the Heritage Crew got a lesson in lithics from the Archaeology department at the Science Museum. Lithics are stone tools like arrowheads, hammerstones, metates (millstones or grinders), and stone blades. Lithics,(or stone tools) come in many different shapes and sizes. Some stone tools are "unifacial" which means that they have been flaked on one side only. Others are "bifacial" which means that they have been flaked on both sides of the rock. There are some stone tools that can be "nonfacial" which means that they were not worked on and just used how they were. Efficient knappers (stone tool makers) can flake off long, thin blades and not have to rework it, and then would be able to haft the blade onto a wood or bone handle. Hammerstones however, were not worked on, they were just stones used to hit and crush objects. They were used in conjunction with anvilstones and usually had spots worn away and made very bumpy.
Courtesy Mark RyanThe new Science Museum of Minnesota exhibit, Maya: Hidden Worlds Revealed has just opened and is a must-see for anyone interested in the ancient and mysterious civilization that once flourished and ruled in Central America. This wide-ranging exploration of the social, political, spiritual and cultural world of the Maya includes artifacts, displays, and hands-on interaction for museum visitors. In conjunction with this very special Science Museum of Minnesota exhibit, the SMM is partnering with the Maya Society of Minnesota to present several lectures at Hamline University during the exhibit's run this summer and into the winter.
I attended the first lecture in the series last Friday night. Archaeologist Jaime Awe
Courtesy Mark Ryan gave a brief overview of the early Maya worldview then talked about his work investigating some impressively large caves in western Belize near where he was born and raised. Inside the caves he and his research team have discovered pottery, torch sticks, writings, and ritualistic artifacts along with human footsteps and unburied skeletal remains, many of children.
Awe hypothesizes that the caves were used by the Maya (from the Classic Period) to make desperate ritualistic pleas by way of human sacrifices to the Maya rain deity. And evidence seems to back him up. Using carbon dating techniques and core analysis of stalactites from the caves, the time-frame of these cave rituals correlate with a period of severe drought in that region of Belize.
The Maya culture is a truly fascinating one. There are several more lectures and workshops to catch each month through next December, and the Maya exhibit at the museum runs through January 5, 2014. By the way, the museum's Omnitheater is also presenting the film Mystery of the Maya. which presents a very nice overview of the early Maya exploration and discoveries. I recommend you view the film first before going through the Maya: Hidden Worlds Revealed exhibit.
Courtesy Mark RyanDo you like fossils? Do you like to draw or take photographs? Then you should know that the 4th annual National Fossil Day Art and Photography Contest is now accepting submissions. The contest runs until next autumn (submissions must be postmarked by October 4th) when judges will select the winning entries. It's all part of the many celebrations of fossils that take place across the country on and around the official National Fossil Day on October 16, 2013. The celebration is a combined effort by the National Park Service along with several federal and state agencies, and earth science related organizations.
There are four age categories: ages 5-8, 9-13, 14-18, and for us old-timers, 19 and up. You can find all the information you need here on the official National Fossil Day contest site.
This year's contest theme is: "Your nomination for our National Fossil". Maybe you think it's should be a dinosaur, or a trilobite, or one of the famous fossil fish found in the Green River shales of the western USA? Whatever you think, get out your pencils, pens, paints, or cameras and make your case for our national fossil.
By the way, Minnesota is one of 10 states in the union lacking an official state fossil. That needs to be remedied. Do you have a favorite fossil found in Minnesota? Maybe you found one yourself at one of the fossil collecting sites around the Twin Cities. If so, let us know in the comments.
Courtesy NASA (via Zonu.com)Back in 1969, when Neil Armstrong and Buzz Aldrin were making their historic moonwalk, I remember thinking to myself, what would happen if some kind of malfunction on the Lunar Module prevented them from blasting off the Moon's surface back to the Command and Service Module? They would most certainly die, there's no doubt about that, because NASA had no rescue plan in place. But what about Michael Collins, the Command Module pilot who was orbiting the Moon in the mother ship? He was waiting to take his fellow crew members home to Earth. If they didn't show up, he'd be in for a pretty lonely and agonizing three-day trip across the quarter-million miles of empty space back to Earth. I wondered what that would have been like.
Fortunately, Apollo 11 was a tremendous success and all three astronauts made it back safely, as did the 18 Apollo astronauts who followed in their footsteps (including the ill-fated Apollo 13 astronauts), so the tragic scenario never played out.
Courtesy NASABut what would that have been like? Astronaut Al Worden probably came closest to experiencing the profound loneliness of isolation in ourter space, when he was piloting the Command Module for the Apollo 15 mission. While his crew mates were busy walking (and driving!) on the Moon's surface, Worden was circling overhead - all by himself - for 3 days. At times, when his craft disappeared behind the far side of the Moon, he had no communications with anyone - not even Mission Control - and was thousands of miles away from his colleagues, and hundreds of thousands of miles away from any other human beings. He holds the record for being the "most isolated human being" ever.
You might think it must have been an anxious time for the solo astronaut, but his story, which can be found here, might just surprise you.
Courtesy Peabody Museum of Natural History, Yale UniversityOn this day in 1877, railroad worker William Harlow Reed came over a ridge-top with the remains of a freshly killed antelope slung over his shoulder, and spotted huge fossilized bones exposed on the side of the steep bluff located a half-mile south of Como Station, a desolate railroad stop on the High Plains of Wyoming. It was a discovery that would forever change his life.
Reed and station master, William Carlin, began collecting up as much as they could, dreaming of money and employment other than railroad work. They waited several months before announcing the discovery in a letter to Yale professor Othniel C. Marsh, at the time one of America's prominent paleontologists. When a crate of bones - along with the guarantee of many more - arrived at Yale, Marsh realized they were dinosaur remains and hired both men to excavate and send him as much as they could, and to keep out any interlopers to his claim. Marsh knew if he could keep it secret - at least for a short time - the fossils at Como Bluff could give him a huge advantage in his rivalry with Philadelphia paleontologist, Edward Drinker Cope, and their notorious Bone Wars.
Courtesy Mark RyanThe dinosaur-rich strata at Como Bluff (the Morrison Formation) are found in the exposed flanks of an anticline (an upward fold), the center of which has been carved out by erosion [see diagram]. All three periods of the Mesozoic Era (Triassic, Jurassic, Cretaceous) are represented in the rock layers found there. Besides dinosaurs, fossils of fish, crocodiles, flying and swimming reptiles have also been found there. A significant number of important Late Jurassic mammalian fossils were discovered and collected by William Reed from Quarry 9 on the east end of Como. Reed also discovered and removed the great Brontosaurus excelsus skeleton that stands today in Yale's Peabody Museum.
Courtesy Peabody Museum of Natural History, Yale UniversityIn the years following its discovery hundreds of tons of dinosaur remains quarried at Como Bluff were shipped to Yale and other institutions pushing America into the forefront of vertebrate paleontology, and heavily influencing how museums would be constructed throughout the world.
Courtesy Mark RyanThe dinosaur halls at the American Museum of Natural History have several mounted specimens found at Como Bluff as does the Smithsonian in our nation's capitol. Well-known genera like Allosaurus, Diplodocus, Apatosaurus, Stegosaurus and Camptosaurus are just a few of the dinosaurs pulled from the mudstones and sandstones at Como Bluff. In the early 20th century it was thought that Como had exhausted its supply of dinosaur remains and exploration there for the most part tapered off for several decades. But in recent years, paleontologist Robert Bakker has been re-examining the quarries and uncovering additional secrets still buried in the Jurassic bluffs at Como.
Courtesy Mark RyanWilliam Reed worked for Marsh for several more years and the two men remained friends until the Yale professor's death in 1899. Reed continued in the field of paleontology, working independently, and for a time with the American Museum of Natural History in New York, and the Carnegie Museum in Pittsburgh. He finished out his career as a popular geology professor and museum curator at the University of Wyoming, just sixty miles from Como Bluff, the great dinosaur graveyard that changed not only the course his life but also that of American paleontology.
Como Bluff was added to the National Register of Historic Places in 1973. It's also been designated as one of Wyoming's National Natural Landmarks by the National Park Service.
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.
Courtesy Mark Ryan
The long spell of unusually hot weather (see Thor's post) may have you looking for some relief, so let me suggest you head for northern Minnesota. No, I’m not talking about Duluth or the North Shore of Lake Superior (it’s been hot there, too), but way up north to the Soudan Underground Mine State Park on the southeast shore of Lake Vermilion (Map). The Soudan Mine is one of several underground mines that once operated in the Ely area, and was the oldest and deepest mine in Minnesota. It’s the perfect place to bring the whole family to learn about Minnesota’s iron mining past and descend a half mile into the earth where you can experience for yourself what it was like to work in an underground mine. An added perk during these steamy summer days is the fact temperature in the mine year-round is a cool 51°F.
In June, my brother Pat and I made one of our frequent geo-tours north, and this time our primary goal was to visit the Soudan mine. After some time exploring Manitou Falls near Superior, Wisconsin, and the eerily fog-shrouded Palisades on the North Shore, we made a beeline up to Ely where we spent the night. The next morning we drove the twenty miles west to Soudan, arriving just after 9am. As we neared our destination, the headframe of Shaft #8 could be seen looming above the ridge-line, making it fairly easy to find the park. Shaft #8 is the operational shaft that takes you underground.
Courtesy Mark RyanThere are two tours into the mine available to the public: the High Energy Physics Lab tour and the Mine History tour. These are separate tours and can't be taken together, and since our time was somewhat limited, Pat and I opted for the history tour. It was slightly longer (about 90 minutes) , included some geology, and seemed like the way to go. So we bought our tickets and while waiting for the tour to start, we checked out the grounds and buildings where the implements and artifacts once used for mining can still be seen. These included the crushing house, the dry house, and drill shop.
Courtesy Mark RyanThe machinery in all these buildings stand idle today, but not so with the engine house. The equipment there still drives the cables and hoist that delivers visitors to and from the mine. Beneath the headframe, Pat sighted several bats fluttering up from the shaft. Three bat species inhabit the mine: the little brown, Eastern pipistrelle, and Northern myotis. But don’t worry, they weren’t any bother at all during the tour.
Across the road from the headframe is a deep, long gash in the ground overgrown with vegetation that was once one of the original open pit mines. Staring down into the hole, it’s not hard to imagine the difficulty the miners faced extracting ore from its steep walls. Pat and I didn’t have time to take the hiking trail far enough to see the much-photographed Soudan Iron Formation outcrop – something I regret - but we did see a couple other open pit mines on the property.
Courtesy Mark RyanThe first iron ore mined in Minnesota was taken from an open pit in Soudan, and shipped by train to Two Harbors at Lake Superior in the early 1880s. The promise of gold had attracted a lot of prospectors to the Arrowhead Region of Minnesota, including George Stuntz, a Duluth civil engineer who established the Vermilion Trail into the area. But instead of gold, he found iron ore. The Vermilion Range, with its rich iron ore, would be the first of several major iron ranges discovered across northern Minnesota. In nearly 80 year of operation, Soudan produced nearly16 million tons of rich iron ore that were shipped across the Great Lakes to steel mills in the East or in later years, sent by train down to the steel mill in Duluth. (I worked at the US Steel mill in Duluth for a year. My first job was on the high-line tracks where iron ore and other steel-making materials were delivered by train to the open hearth furnaces. During lunch, I’d watch my co-workers tap the furnaces. When the molten steel was ready to go, alarms and sirens would sound as a small bomb was sent into the furnace that would blow out the plug, forcing the molten steel to pour out into giant multi-ton ladles. Very impressive and extremely noisy!).
At 10am sharp we gathered with other visitors for the tour. After a quick video explaining an overview of the mine and its history, everyone grabbed a hardhat and loaded into the shaft’s elevator or “man cage” as the miners called it. A dozen of us crammed into the cage for the ride down. It wasn't too bad but it bordered on stuffy, especially in the heat. Our tour guide, a very pleasant young woman, eagerly imparted her knowledge of the mine’s history and the safety issues involved with the tour. She informed us that back when the mine was operational eighteen miners usually wedged into the cage for each transport.
Courtesy Minnesota Geological SurveyThe ride down to Level 27 took under three minutes. The shaft is angled about 78 degrees so besides traveling half a mile underground we also moved 500 feet north of the headframe and underneath the nearby old open pit mine. During our rattling, rapid descent, our guide held her flashlight against the scuffed window so we could see something - the occasional reflection of dim light as we shot past levels - otherwise it would've been a pretty dark ride. Two levels (#12 and #22) were lighted because they’re still used to pump out the relatively little water seeping into the mine.
Courtesy Mark RyanLevel 27, the deepest level in the shaft, was lighted, too, at least where the elevator stopped. The physics lab is located on the same level and we could see its entrance as we exited the elevator. We were joined by a couple more guides who herded us into small rail cars for the last leg of the trip, this time horizontally through a dimly-lit 3/4 mile passageway called a drift. The mineshaft and drift were dug out through Ely greenstone. As promised the temperature in the mine was a cool 51°F and a refreshing break from the surface heat. At least I thought so. Some folks were wearing sweatshirts or light jackets, but I was comfortable in just a t-shirt and shorts.
Courtesy Mark RyanAt the end of the tunnel we detrained and were led up a metal spiral staircase (the miners used ladders) to reach the stope, a large, cavernous space carved into of the ore layer. Our guide pointed out some of the geological features including adjacent greenstone layers, mineral veins of copper, and of course, hematite. She explained how holes were drilled into the walls of the ore body, and explosives placed inside for blasting. After the controlled explosion, and before any miners were allowed in, a barman was sent in to knock down any loose rock from the ceiling. Barring was one of the higher paying jobs in the mine but probably the most dangerous.
The miners used the “cut and fill” method to mine the ore from the ceiling. Waste rock was let drop and used to create an ever-rising artificial floor that remained pretty much the same distance from the ceiling being mined. This eliminated waste rock disposal to the surface. The dense ore, which weighed as much as 325 pounds per cubic foot, was sent down chutes into granby cars on the level below them for transportation back to the skip that carried it up to the top. The granby cars and skip each held 6 tons of ore and miners were paid according to the amount of ore they sent up to the surface. There, the ore was dumped into larry cars and transported to the crusher house for crushing, then either loaded into waiting train cars or stockpiled for later shipping.
Courtesy Jvstin via FlickrThe iron deposits found at Soudan precipitated out of an ancient sea during the Early Precambrian period about 2.7 billion years ago. The iron was deposited on pillow basalts extruded during earlier volcanic activity. Pillow basalts form when molten rock comes in contact with water. The iron, which also originated from volcanic activity, interbedded with deposits of mud and sand forming what’s called a banded iron formation or BIF. Unlike the large and extensive single bed of iron ore occurring in the Mesabi Range, the iron ore at Soudan was laid out in small lenses. More pillow basalt flowed atop the iron layers. Later, probably through hydrologic processes, the iron content was enriched and the entire sequence tightly folded and deformed by tectonic forces from regional mountain-building episodes (orogenies) and later baked by the underground upwelling of magma during intrusion of the Duluth Complex gabbro. The heat and pressure metamorphosed the sequence, transforming the basalt into Ely greenstone (shist). The entire sequence eventually ended up nearly vertical in an anticline with layers of hematite, jasper, and chert sandwiched between layers of greenstone (also known as chlorite).
Miners working the underground mine at Soudan often referred to it as the “The Cadillac of Mines”. Compared with other underground mines near Ely, it was relatively dry, the temperature was a comfortable 51 degrees year round, and fresh air permeated all the levels. But to show that it wasn’t all rosy, our guide demonstrated what it must have been like for the miners before electricity. The mine chamber was well lighted for us tourists but to give us an idea what the early miners experienced she extinguished all the lights and held a single burning candle near her face. It wasn’t very bright at all and kind of spooky.
Courtesy Mark RyanLater, when electricity was put in, lighting improved, and power drills were used in the mining process. After a sufficient warning, our guide played for us a recording of the sound made by a single drill at work just to give us an idea of the noise level produced. The decibel level I remember from working in the steel mill was nothing compared to what the miners must have endured when several drills were going at once. It’s no wonder many of them suffered hearing loss after years working the mine.
As steelmaking processes were refined, the need for Soudan’s rich ore diminished. Using low-grade iron taconite became more economical for use with new oxygen-fed furnaces. Soudan shut down operations in 1962. The next year, after all the stockpiled ore had been shipped, US Steel Corporation gave the mine and an additional 1100 acres of land to the state of Minnesota for $1. The stipulation was that the site be used for educational purposes. Minnesota turned the site into a state park in 1965.
Courtesy Mark RyanI found the Soudan Underground Mine State Park well worth the trip. Where else can you travel a half-mile underground into 2.7 billion year-old rock formations and cool off at the same time? (The temperature at the bottom of the Grand Canyon is much hotter than at the top). Soudan's a great place to learn about Minnesota mining history, see area wildlife and check out some of the unique geology in the Lake Vermilion region that helped make Minnesota a leading iron ore producer.
Entry to the park is free and requires no state park sticker. The mine tours, however, require a fee. Pat and I paid $12 each. Kids are cheaper. The tours begin on the hour from 10am to 4pm daily. Tours for the High Energy Physics Lab occur only twice each day, the first at 10am and the second at 4pm. As I mentioned before, you can't combine tours so you have to pick either the historic one or the physics one. Mine tours are available from late May until the end of September. Follow this link for additional information.
On our way home, Pat and I agreed we'd come back sometime soon for the High Energy Physics Lab tour where physicists investigate things like the particle mass of neutrinos, and detect other dark matter particles. The lab is run by the University of Minnesota. However, I recently learned there’s a third mine tour available at Soudan, one offered only to organized groups. This one is more geology-focused and instead of riding the train through the 3/4 mile of Ely greenstone to the ore body, participants walk through the drift and are given a detailed lesson in geology along the way. I definitely have to join me up with one of those groups. Maybe next summer.
Did I mention it’s 51°F in the mine?
Short video of Soudan Underground Mine tour
Minnesota mining history
More DNR Soudan info
Gigapan of Soudan Mine site
Soudan at Wikipedia
DNR Soudan Mine site
MN Conservation Volunteer article on Soudan Mine
Paleontologist Dr. Howard Falcon-Lang found the 314 slides while searching through the vaults of the Survey headquarters near Keyworth, UK. Each slide contains a polished thin section of a fossil plant, prepared for viewing under a microscope. But the best thing about the discovery is that some of the slides are of specimens collected by the young Charles Darwin during his legendary voyage on the Beagle. Darwin’s theory of evolution and subsequent book On the Origin of Species resulted from much of what he discovered during the five-year voyage. Among the specimens collected by Darwin is a piece of petrified wood from an island off the coast of Chile in 1834.
Falcon-Lang figures the collection has been languishing unregistered in the cabinet for 165 years. Joseph Hooker, a botanist and close friend of Darwin, worked briefly for the Geological Survey in the early 19th century, and given the job of cataloging the collection. But before Hooker could properly register the fossils, he left on an expedition to the Himalayas and the collection was soon forgotten. In the passing years the cabinet got moved several times until it reached its current storage place deep in the recesses of the Geological Survey where it was found in April of last year.
According to Falcon-Lang the lost fossils, some of which can be viewed on line, will add greatly to current science, and he expects some great scientific papers to result from the collection.