Stories tagged Structure of Matter


GrapheneCourtesy Carbophiliac

Graphene is great

Graphene is a single atom thick layer of carbon atoms in a honeycomb like arrangement (read more about graphene here in

Graphene transistors are the fastest

Transistors are like valves that can turn the flow of electricity off and on. Computers can use transistors and logic circuits to solve all kinds of problems. These problems can be solved faster if the transistors can turn on and off faster. Transistors made out of graphene now can switch on and off 100 billion times per second (100 GigaHertz). State-of-the-art silicon transistors of the same gate length have a switching frequency of about 40 GigaHertz.

IBM develops next-generation transistors

IBM just announced their breakthrough in the magazine Science.

Uniform and high-quality graphene wafers were synthesized by thermal decomposition of a silicon carbide (SiC) substrate. The graphene transistor itself utilized a metal top-gate architecture and a novel gate insulator stack involving a polymer and a high dielectric constant oxide. The gate length was modest, 240 nanometers, leaving plenty of space for further optimization of its performance by scaling down the gate length. ScienceDaily


Black light magic

Fluorescent minerals: Click "hgrobe" link for mineral identification
Fluorescent minerals: Click "hgrobe" link for mineral identificationCourtesy hgrobe
Last week, while volunteering at Collector's Corner at the Science Museum of Minnesota, a visitor asked me if we had a black light. I explained that black lights worked best in black (dark) rooms so we put our black light in a black box. By holding minerals under the black light within the black box, one can sometimes see colors not visible when viewed normally.

The beautiful colors seen are a result of fluorescence. Fluorescence happens when electrons absorb energy from the high energy light and re-emit light of a lower, visible wavelength. Black lights get their name because the ultraviolet light from them is invisible. It has a lot of energy, though. Too much exposure to ultraviolet light will result in sunburn or eye damage.

Fluorescence is useful in research

Fluorescent cells: Bovine pulmonary arthery endothelial cells
Fluorescent cells: Bovine pulmonary arthery endothelial cellsCourtesy U S Govt
Fluorescence allows tracking or analysis of biological molecules. By attaching variously colored "tags", beautiful and useful images are allowing scientists to better understand what is happening, and where. In this image of endothelial cells, nuclei are stained blue with DAPI, microtubles are marked green by an antibody and actin filaments are labeled red with phalloidin. Last year the Nobel Prize in Chemistry was awarded to Osamu Shimomura, Martin Chalfie and Roger Tsien for their work with fluorescence.

More fluorescence fun

I just saw a BoingBoing post about fluorescence. Click the link to see more, but I embedded one of the You Tube videos below.

Tonic water fluorescence


GOCE Satellite: The Gravity field and steady-state Ocean Circulation Explorer
GOCE Satellite: The Gravity field and steady-state Ocean Circulation ExplorerCourtesy ESA
Can it be true? Yes, for a mere $5,544 dollars round-trip airfare to Greenland! In March 2009, the European Space Agency launched the Gravity field and steady-state Ocean Circulation Explorer (GOCE) into orbit around our planet, which is now transmitting detailed data about the Earth’s gravity. The GOCE satellite uses a gradiometer to map tiny variations in the Earth’s gravity caused by the planet’s rotation, mountains, ocean trenches, and interior density. New maps illustrating gravity gradients on the Earth are being produced from the information beamed back from GOCE. Preliminary data suggests that there is a negative shift in gravity in the northeastern region of Greenland where the Earth’s tug is a little less, which means you might weigh a fraction of a pound lighter there (a very small fraction, so it may not be worth the plane fare)!

In America, NASA and Stanford University are also working on the gravity issue. Gravity Probe B (GP-B) is a satellite orbiting 642 km (400 miles) above the Earth and uses four gyroscopes and a telescope to measure two physical effects of Einstein’s Theory of General Relativity on the Earth: the Geodetic Effect, which is the amount the earth warps its spacetime, and the Frame-Dragging Effect, the amount of spacetime the earth drags with it as it rotates. (Spacetime is the combination of the three dimensions of space with the one dimension of time into a mathematical model.)

Quick overview time. The Theory of General Relativity is simply defined as: matter telling spacetime how to curve, and curved spacetime telling matter how to move. Imagine that the Earth (matter) is a bowling ball and spacetime is a trampoline. If you place the bowling ball in the center of the trampoline it stretches the trampoline down. Matter (the bowling ball) curves or distorts the spacetime (trampoline). Now toss a smaller ball, like a marble, onto the trampoline. Naturally, it will roll towards the bowling ball, but the bowling ball isn’t ‘attracting’ the marble, the path or movement of the marble towards the center is affected by the deformed shape of the trampoline. The spacetime (trampoline) is telling the matter (marble) how to move. This is different than Newton’s theory of gravity, which implies that the earth is attracting or pulling objects towards it in a straight line. Of course, this is just a simplified explanation; the real physics can be more complicated because of other factors like acceleration.

Albert Einstein
Albert EinsteinCourtesy none
So what is the point of all this high-tech gravity testing? First of all, our current understanding of the structure of the universe and the motion of matter is based on Albert Einstein’s Theory of General Relativity; elaborate concepts and mathematical equations conceived by a genius long before we had the technology to directly test them for accuracy. The Theory of General Relativity is the cornerstone of modern physics, used to describe the universe and everything in it, and yet it is the least tested of Einstein’s amazing theories. Testing the Frame-Dragging Effect is particularly exciting for physicists because they can use the data about the Earth’s influence on spacetime to measure the properties of black holes and quasars.

Second, the data from the GOCE satellite will help accurately measure the real acceleration due to gravity on the earth, which can vary from 9.78 to 9.83 meters per second squared around the planet. This will help scientists analyze ocean circulation and sea level changes, which are influenced by our climate and climate change. The information that the GOCE beams back will also assist researchers studying geological processes such as earthquakes and volcanoes.

So, as I gobble down another mouthful of leftover turkey and mashed potatoes, I can feel confident that my holiday weight gain and the structure of the universe are of grave importance to the physicists of the world!


I'm not sayin, I'm just sayin...
I'm not sayin, I'm just sayin...Courtesy ROOTS UP
I don't need scientists to tell me there are hints of dark matter on Minnesota's Iron Range. Have you heard that Bob Dylan song, North Country Blues? If you believe Bob, the Iron Range can be a pretty depressing place. A dark place, full of dark matter. Are you following me here?

It turns out that Bob Dylan grew-up not far from a very deep hole in the ground known as the Soudan mine. It used to be an iron mine, but as he points out in that song I mentioned, "The shaft was soon shut, and more work was cut, and the fire in the air, it felt frozen." Hmmm...what did he mean by "fire in the air"?

He may not have been referring to the Soudan mine in particular, but it seems a little bit odd that around the time he released Down in the Groove, a terrible album, this half-mile deep mine was reopened by scientific researchers as a high-energy physics laboratory. Deep beneath the ground, shielded from outside particle interference by the surrounding geologic formations, researchers began studying things like neutrinos and proton decay, searching for WIMPS (Weakly Interacting Massive Particles) and conducting something called a Cryogenic Dark Matter Search.

So Bob Dylan and a bunch of scientists, all hanging out on the Iron Range, all thinking about the nature of the universe. I'm telling you, this is no coincidence. I don't mean to imply that Bob Dylan writes his songs inside a physics laboratory a half mile beneath the Iron Range, but wouldn't that just make so much sense?

Recently a team of scientists working in this very underground lab announced that they may have detected particles of dark matter, invisible material that could lead to huge breakthroughs in both physics and astronomy. HUGE BREAKTHROUGHS. I would explain more, but to be honest, I don't really understand physics. Perhaps one of you can chime in?

Bob Dylan also recently released a new album of Christmas songs. Are these events related? You tell me.

This MinnPost article explains more about the recent scientific discovery. You can also look back at this Science Buzz post about dark matter, or follow-up on this conversation with physicist Prisca Cushman, who knows all about WIMPS and Dark Matter, and may even know Bob Dylan. On that note, this is pretty funny.


Flash memory: Today's content king.
Flash memory: Today's content king.Courtesy Nrbelex


MRAM (magnetoresistive random access memory) flips the magnetisation of a region 180 degrees relative to another permanently magnetised region to store a 0 or a 1. MRAM is nanosecond fast but if made too small and close together will "cross talk".


FeRAM (ferroelectric random access memory) use small external electric fields to polarize ferroelectric crystals. FeRAMs low energy requirement and speed advantage is offset by the requirement that every memory bit requires a space hogging capacitor.


PCRAM (phase-change random access memory) use laser light or current to change a materials structure. If the current pulse is long, the material orders itself into its crystalline state (a conductor). If the pulse is short, the material cools abruptly into the amorphous state (an insulator). These memory regions can be made quite small, but the downside is that the melting requires lots of energy.


RRAM (resistive random access memory) use high voltages to drive off or reabsorb oxygen bound within molecules like titanium oxide. When the oxygen leaves, it leaves behind holes in the crystal and excess electrons that are available for conduction. This process requires almost no electrical current, making them very energy efficient. Another exciting property is that RRAMs can represent more than a 0 or 1. They are able to adopt any number of values for their resistance (memristors) which could make them models for the analogue computational elements (synapses) inside the human brain.

Racetrack memory

Racetrack memory moves tiny domains of magnetism along wires. The domains are moved along the wire by a current and written or read when they pass sensor heads. If the wires can be coiled into 3 D, the memory per volume will increase several hundred times.

Source: New Scientist


Vat grown meat?: In five years, it could be yours.
Vat grown meat?: In five years, it could be yours.Courtesy Jorren
These are confusing times we live in. Are vampires legitimate objects of sexual desire, or is wanting to make out with a 100-year-old man still weird? What are dolphins thinking about? And what will you be eating in ten years?

It’s overwhelming, isn’t it? But Science Buzz is here to help. Here are the answers to the preceding pressing questions, in order: Yes, because when have millions of teenagers ever been wrong?; depends on the 100-year-old man, and if he’s interested too; sex, hunting, and horrible combinations of the two; and lab-grown meat.

We’ve talked about “artificial” meat here on the Buzz before, because it’s so weird, sciencey and awesome, but that was four years ago, and some wild things have developed since then.

Just in time for Thanksgiving, scientists in the Netherlands have created artificial muscles… for eating! The articles I found about the announcement were, unfortunately, pretty vague, and I’m not sure exactly what this muscle mass is like. It’s not a huge challenge to get a bunch of muscle cells to reproduce outside of a living animal, but getting them grow into a real muscle (and recognizable meat, instead of a formless mass of cells) is more difficult. It’s a similar problem to growing new organs for transplant, and similar methods have been tested; researchers are experimenting with using a collagen “skeleton” of a muscle for muscle cells to grow on. I think that the researchers in the Nethelands may have done something like this, because they’ve grown pig cells into what they’re referring to as “soggy pork,” a substance like “wasted muscle.” Just getting the structure right, it seems, is not quite enough for having lab-grown meat (or “in vitro meat”) that tastes and feels like the real thing. The scientists still need to figure out a way to “exercise” the bodiless muscle, but they think that they’re close enough to a solution that they claim the artificial meat could be on sale within five years. But, then again, that’s what this guy said five years ago, and in the 1930s, Winston Churchill said we’d be growing meat outside of animals within 50 years, so what do they know? Maybe they’re onto something this time, though—a sausage company is backing the research, and it’s thought that the first real fake muscles will be pretty small, and best used in ground meat applications. Like sausages.

It’s an interesting idea, in vitro meat. Unlike cloned meat, which still comes from a living, cloned animal, in vitro meat would never come from a whole animal, so there would be no animal cruelty. The original cells could be taken via biopsy, too, leaving the animal unharmed. It’s also hoped that meat-growing processes could eventually be better for the environment, because they wouldn’t require land to live on, or for growing feed crops, or as much fuel to move around, and they wouldn’t constantly be farting and producing methane (A very potent greenhouse gas). And while scientists in laboratories are doing these early experiments, commercial scale operations would be more like yeast- or yogurt-producing facilities. Even PETA, ever looking for trouble in the oddest places seems to be ok with the idea of in vitro meat, because it doesn’t require animals to be hurt or killed.

But would you eat it? Are you more or less comfortable with meat that was grown in a vat than with meat grown in an animal’s body?


A concerned citizen preforms a simplified self test: Results are positive.
A concerned citizen preforms a simplified self test: Results are positive.Courtesy kevjblack
The Large Hadron Collider, the LHC, the World Destroyer, the Hula Hoop of God, the RC Matchbox Racetrack of Zeus, the Contraceptive Ring of Gaia herself… has been turned on.

You remember how concerned you were about this, right? You were worried that, based on what that friend said and what you read on that webpage, the activation of the LHC could be the end of the world, if not the universe.

Well, I know you’re nervous about what you might find, but I think there’s no avoiding it—it’s time for our regular self-check. I’ll walk you through it.

Stand up, and place your arms at your sides, palms in. Move your hands back and towards each other, keeping the palms facing in. When your hands have nearly met behind you, pull them forward and make a grabbing motion with your hands.

Did your hands go through thin air, or did they encounter something soft yet substantial? If the latter is true, we can all breath a sigh of relief—the LHC didn’t destroy life as we know it, and your butt is safe. For now.

The collider was actually turned on on Friday, although the first collisions from its accelerating beams of particles weren’t expected until early December. Much to the scientists’ surprise, collisions were detected as early as Monday. Check again if you need to, Buzzketeers.

If you’re looking for something to worry about, however, you might consider the following: the machine isn’t anywhere near full power yet. The protons involved in Monday’s collisions had been accelerated to the point where they had 450 billion electron volts. In the next few weeks, the LHC team will accelerate the particles up to 1.2 trillion electron volts, and, eventually, the facility should be accelerating protons to 7 trillion electron volts. When you’ve got protons heading each way, that means collisions will involve 14 trillion electron volts.

Yowza, right? I mean, the next most powerful particle accelerator, the Tevatron in Illinois, can only inject 900 billion electron volts into its accelerating particles—the LHC can do more than 15 times that!

But what does that mean? That sounds like a frightening amount of energy, so why doesn’t the Earth rumble and moan like a house in a storm whenever a large particle accelerator is turned on? It is a lot of energy, especially when you’re concentrating it into individual protons, which are, of course, very very small. But an electron volt is a very small unit of energy; it is defined as being “equal to the amount of kinetic energy gained by a single unbound electron when it accelerates through an electrostatic potential difference of one volt.” One trillion (that’s a million millions) electron volts—one fourteenth of the total energy of the LHC’s biggest possible collisions—is approximately equal to “the amount of energy of the motion of a flying mosquito.” That might be a deceptively small analogy—I’m sure it takes much much much more than a few bugs on treadmills to get the LHC powered up, and, again, that’s a lot of energy to be concentrated in a single subatomic particle racing at nearly the speed of light—but it’s an interesting comparison.

Strangelets and micro black wholes: 0; continued existence: 1.


For me, the greatest mystery in the universe is Lindsay Price, and how she continues to find work.: Not that great a mystery, I guess…
For me, the greatest mystery in the universe is Lindsay Price, and how she continues to find work.: Not that great a mystery, I guess…Courtesy catechism

And, let’s face it, who hasn’t had the urge now and then? At the “Quantum to Cosmos” physics conference in Waterloo, Canada, seven physicists were asked, "What keeps you awake at night?" (Apparently, they meant “what issue in science” as opposed to love, money, or lack thereof.) The panel came up with some pretty heavy questions:

Why are the fundamental laws of nature the way that they are? There doesn’t seem to be any reason why they couldn’t be some other way. Are there, perhaps, other universes with other rules?

How does the Observer Effect work? This is a little deep for me, but apparently at the sub-atomic level, simply observing a particle over here can effect another particle thousands of miles away. How does nature do that?

What is the nature of matter, anyway? Especially the “dark matter” which is theorized to exist in outer space, messing up all our gravity calculations.

On a related note, will string theory ever be proven? String theory is the latest theory for how matter and energy interact at the sub-sub-sub-atomic level. And while it is very elegant and seems right on paper, no one has any idea how to conduct an experiment to prove or disprove it.

How do complex systems arise out of simple, basic particles and forces? You know, complex systems. Like life, the universe, and everything.

How did the universe begin, anyway? Physics can only take us back to a few fractions of a second after the Big Bang, a moment at which the universe was very small, very hot, and very dense. Before that, the laws of physics break down. No one knows how to describe the Bang itself, or how / why it happened.

Which brings us to, what are the limits of science? Science is based on observation and experiment. But, at some point, you run into ideas that can’t be tested. In theory, it’s entirely possible that there are other universes. But we’re stuck in this one—how would we ever know?

If anyone has answers to any of these questions, please send them to Canada ASAP. It sounds like there’s a bunch of scientists up there who could use a good night’s sleep.


The golden web of an orb-weaver: Little does this spider suspect that it is about to be captured and milked by the clinically insane.
The golden web of an orb-weaver: Little does this spider suspect that it is about to be captured and milked by the clinically insane.Courtesy Tai Po Kau Nature Reserve
After decades of frustration and failure, mankind’s dream of weaving a blanket entirely from the stuff of nightmares has become a reality.

For centuries, the very possibility of creating fabric from nightmares was considered little more than a fever dream, and the criminally insane resigned themselves to nightmare cloth substitutes, like hammered-flat baby rabbits, and prison toilet paper. Inventive though these are, like soymilk, they fooled no one.

Then, at the end of the 19th century, reports began to filter from Africa that a French missionary in Madagascar, exploring the dark peaks of his own madness, was creating fabrics of almost pure nightmare.

The missionary had supposedly created a spider-milking machine, into which he was placing massive Golden orb-weaver spiders, collected in their hundreds by local young girls. (Having little girls collect the spiders made the nightmare purer, but was not strictly necessary. Leave it to a missionary for such meticulous detail.)

The spiders were restrained in “a sort of stocks,” and then the beginnings of a strand of silk was coaxed from their abdomens and attached to a hand cranked wheel, at which point several hundred yards of the orb-weavers’ characteristically golden silk could be withdrawn from each spider. When the creatures could yield no more silk, they were released, apparently unharmed, back into the wild, where they would regenerate their webbing material after several days. The spooled spider silk could then be woven like any other material… but scarier.

Seemingly too “good” to be true, the missionary’s experiments were never replicated, and generations of madmen made do with sheets of dried bat saliva and mortuary blankets. Until now.

A “textile expert” and a visionary in what liberal arts colleges refer to as “insane studies,” Simon Peers and Nicholas Godley, recreated the missionary’s spider-milking machine, and after four years and one million spiders they have created an indestructible golden blanket, woven of pure nightmares.

The madmen discovered that while a single spider might produce a strand of silk up to 400 meters long, the material is, of course, exceptionally light. It took approximately 14,000 spiders to produce a single once of silk. The final 11 foot by 4 foot piece of fabric weighed about 2.4 pounds (~38 oz). So many, many spiders were involved, and lots of time. To help pass the long months of spider-milking, the artists whispered their secrets into mouse holes, and built razor blade houses.

The final intricately patterned textile has a rich, naturally golden color—the golden orb-weaver is named for the color of its silk, which attracts pollen-seeking insects in sunlight, and blends with background foliage in shadow. The spiders can adjust the exact tone of their webbing based on ambient light levels and color, so this textile has a unique shade based on how a million spiders perceived the room containing the tiny spider stocks.

The fabric is also exceptionally strong. Spider silk can stretch to 140% without breaking, and has tensile strength comparable to or exceeding that of modern fabrics like Kevlar, used for bullet-proof body armor. The complex protein structure that gives spider silk its strength has also makes it very difficult to reproduce artificially (that is, it hasn’t been done). Attempts have been made to insert the gene for spider silk protein production into goats, which then produce the protein in their milk, if not actual fibers. Unlike silk moths, spiders aren’t suited for mass production of silk, as they tend to kill and eat each other. And so it takes a madman, obsessed with drawing the secreted material for trapping prey from a hand-sized, venomous arachnid predator, to obtain enough spider silk to actually make something form it.

Despite civilization’s unwritten, yet long-standing rules against allowing madmen to have golden bulletproof cloaks, there is little to be done in this situation, seeing as how they made it themselves. Out of nightmares.

The textile is now on display at the American Museum of Natural History. (And, again, a photo of it can be seen here.


Trailhead sign
Trailhead signCourtesy Mark Ryan
In the latter days of summer my wife and I took a drive up the Gunflint Trail and visited the Magnetic Rock Trail, a spur trail jutting off the Gunflint near Gunflint Lake. Our original plans of lounging about the North Shore of Lake Superior had been scuttled by a mix-up in our cabin reservations, so I saw it as an opportunity to check out first-hand some of the local geology. I had visited the MRT briefly once before and my reasons for wanting to make the 50-mile drive from Grand Marais to revisit the trail were three-fold: stromatolites, meteorite impact ejecta, and, of course, magnetic rocks

Well, as it turns out, I wasn’t very successful,

Signs of recent fire: Evidence of forest fire can still be seen along the Magnetic Rock Trail.
Signs of recent fire: Evidence of forest fire can still be seen along the Magnetic Rock Trail.Courtesy Mark Ryan
Readers may recall the Ham Lake forest fires raged along the Gunflint Trail in the early summer of 2007, destroying several hundred acres of the surrounding forest along with resorts and private property. The fire, it was later determined, was started by a legal campfire in the vicinity of Ham Lake that had gotten out of hand and spread quickly through the region. It was the second forest fire to rage through the Magnetic Rock Trail (MRT) in the past two decades (there was also a controlled burn in 2002). The latest fire removed much of the pine canopy that covered the area, opening it to more sky and sunlight, and new vistas of the surrounding terrain.

Idyllic scene at a pond along the Magnetic Rock Trail
Idyllic scene at a pond along the Magnetic Rock TrailCourtesy Mark Ryan
A new jack pine rises from the ashes
A new jack pine rises from the ashesCourtesy Mark Ryan
But as destructive as forest fires can be, they do have their upside. Forests are quick to revitalize after fires. New trees soon rise up from the ashes, and evidence of that in the MRT was apparent in the many jack pines (Pinus banksiana) we saw sprouting up everywhere. But trees aren’t the only affected flora. A lot of the groundcover gets incinerated as well, sometimes exposing patches of bedrock. In the case of the Magnetic Rock Trail, it meant new outcrops of the Gunflint Iron Formation were uncovered, revealing fresh unexplored exposures.

The Gunflint Iron Formation is a mass of iron ore taconite that spans from the Arrowhead region of Minnesota eastward into Ontario, Canada with the majority of the formation located on the Canadian side of the border. Most iron formations on Earth were formed around the same time, about 2 billion years ago during the Middle Pre-Cambrian (Early Proterozoic) times. A shallow sea (the Animikie) covered much of northern Minnesota and eastern Ontario at the time. The sea teemed with cyanobacteria in the form of stromatolites; thick microbial mats that helped oxygenate the Earth’s atmosphere and metabolize iron out of solution through photosynthesis. The iron-oxide sediments later became the iron ranges that span across northern Minnesota and Canada. Much of the rock along the Magnetic Rock Trail is composed of magnetite (Fe3 O4) inter-bedded with layers of chert or shale. Magnetite is the most magnetic of all the naturally occurring minerals, hence its name. The Gunflint Iron Formation is particularly resistant to erosion on the Minnesota side probably due to its nearness to the Duluth Complex intrusives. These influxes of magma moved into the area around 1.1 billion years ago, adding tremendous heat to the existing strata. The portion of the Gunflint Iron Formations (that located in Minnesota) closest to the heat source shows the most resistance to erosion.

Stromatolites and not?: Stromatolites by geologist Jim Miller, MN Geological Survey (top); maybe not stromatolites by author (bottom)
Stromatolites and not?: Stromatolites by geologist Jim Miller, MN Geological Survey (top); maybe not stromatolites by author (bottom)Courtesy Jim Miller, MN Geological Survey (top) Mark Ryan (bottom)
Preserved within some of the newly exposed outcrops along the MRT are fossil records of these stromatolites, representing some of the oldest fossils found in Minnesota. Gunflint stromatolites contain large numbers of fossils that can be seen under a scanning electron microscope. I had been told that you can walk off the main path and find some of these ancient fossils, so I searched off-trail for a while and found what I thought were stromatolites, and took photos of them.

But later when I consulted with geologist Mark Jirsa, he wasn’t so sure.

“You're looking at thin bedding in the iron formation that dips shallowly in comparison to the dip of the outcrop surface,” he wrote me. “The result is a swirly look, that looks deceptively like stromatolite mounds.”

Jirsa was in the field when I contacted him, and his Internet capability was limited, so when he tried to send me some photos of what the stromatolites actually looked like, they didn’t come through. However, his colleague, geologist Jim Miller (who also supplied welcomed assistance with this post) sent me a stromatolite photo he had taken at MRT.

Personally, I can’t tell the difference, but then I’m no geologist. so I have to bow to the professionals.

My second quest – to locate and photograph ejecta from the Sudbury Impact – wasn’t successful either. The aforementioned Mark Jirsa discovered this record of a 1.85 billion-year-old meteor impact in 2007. I wrote a previous post about it that same year so I won’t go into those details (you can read it here) but I will bring you up to speed on how he’s since interpreted the find.

Briefly, the Sudbury Impact Crater is located in Ontario, Canada, and was made by a meteorite about 10-miles in diameter that slammed into the Earth 1.85 million years ago. The 150-mile wide crater is the second largest known on the planet. The collision sent a tremendous firestorm of superheated material into the atmosphere, and some of it coalesced like hailstones and landed 480 miles away in northeastern Minnesota. This is what Jirsa discovered two years ago: a layer of ejecta mixed with torn up pieces (breccia ) of the Gunflint Formation, and all of it overlain by a younger layer of slate known as the Rove Formation. He published an article about it in Astronomy magazine, and there’s also a PDF file downloadable from Minnesota Geological Survey website (the link is located in the upper left of the MGS homepage).

Debris from Sudbury Impact found in Minnesota: Photo by Mark Jirsa, Minnesota Geological Survey
Debris from Sudbury Impact found in Minnesota: Photo by Mark Jirsa, Minnesota Geological Survey
What Jirsa found was quite remarkable: a layer of churned-up rocks laid down above the Gunflint Iron Formation. The odd jumble of rock included berry-shaped rocks known as accretionary lapilli, intermixed with the Gunflint Iron Formation rock. According to his interpretation, what is seen in the layer essentially shows the events of a single day in the geological record. And a nasty day it must have been.

Three minutes after the initial fireball impact at Sudbury, seismic waves from earthquakes measuring more than magnitude-10 on the Richter Scale reached the Animikie basin, ripping loose the iron formation off the seafloor crust, and redistributed it along a submarine slope. Within 10 minutes, a firestorm of molten material hailed down from the sky covering the region with from 3 to 10 feet of ejecta in the form of accretionary lapilli. Ultra-hurricane-force winds measuring up to 1400 mph(!) blasted over the shallow sea soon after, followed by the coup de grace – titanic tsunamis the likes of which have never been seen since which tossed everything into a stew of breccia (jumbled rock) and berry-shaped ejecta.

This day of horror took place sometime in the 48 million year interim that separates the Gunflint Iron Formation and the time the sediments of the Rove Formation were laid down above it. The entire concoction was later baked and metamorphosed by the intrusive magmas of the Duluth Complex.

How hard could it be to find evidence of a mess like this? Well, considering the MRT covers a large area, and since I had no information pinpointing any locations, it was like looking for a needle in a haystack – a very large haystack. In the end, I soon gave up because I really didn’t know what I was looking for and I realized how futile it probably would be. However, I’ve sure learned a whole lot about it now.

Magnetic Rock Trail's rocks are magnetic: as my handy magnet proves.
Magnetic Rock Trail's rocks are magnetic: as my handy magnet proves.Courtesy Mark Ryan
Initially, I thought at least my third quest – finding magnetic rock – would be a complete success because just about every rock exposed along the MRT is highly magnetic (I had a magnet with me and I can attest to that fact – see photo). It made sense that the whole reason the trail is called the Magnetic Rock Trail is because of all the magnetic rocks found there. But I’ve since learned I was once again totally wrong. The trail is name after a single large magnetic rock that’s about 1.5 miles up the trail. This 30-foot monolith stands upright and obvious in the middle of the forest and its notoriety dates back to early native American times. It is a chunk of the Gunflint Iron Formation – and highly magnetic like the rest of the rock in the area – but is deemed an erratic moved into place from a short distance away by glaciers during the last Ice Age. Had I read any of the brochures I had collected on our trip sometime other than when I got home, I would have known this before I even got there. But as it was, we didn’t walk that far into the trail so we missed it completely. Oh, well.

Blueberry picking: Mrs. R collects blueberries near the Magnetic Rock Trail.
Blueberry picking: Mrs. R collects blueberries near the Magnetic Rock Trail.Courtesy Mark Ryan
But even though my three main objectives for visiting the MRT were pretty much complete washouts, there was one unexpected surprise that will probably draw us back to the region next year: blueberries.

Blueberries and metamorphism: The real attraction at the Magnetic Rock Trail?
Blueberries and metamorphism: The real attraction at the Magnetic Rock Trail?Courtesy Mark Ryan
Wild blueberries (Vaccinium angustifolium) were all over the place. The low-bush berries thrive in sandy, acid soils of forest clearings, and in rocky areas around pines forests – just the type of environments you find around the MRT. So, once I finished with my failed geological studies, I assisted my wife in picking as many wild blueberries as we needed. We kept them in our cooler for the ride home, and as Mrs. R is prone to do, she jumbled all the berries together into a viscous concoction, all within a flakey crust that was heated over time at a very high-temperature.

The result looked something like the Sudbury Impact ejecta layer found near the Magnetic Rock Trail, but it was much more delicious, and a great way to end the summer.

Forest regrowth on Buzz
More about stromatolites
Top Ten Most Impressive Impact Craters
More about Minnesota geology