Stories tagged geology

Literally dig deeper into the earth surface and discover what is lying right under your feet.

Oct
07
2010

What if I told you University of Minnesota geology and geophysics professor, Martin Saar, says geothermal energy can be made even greener through carbon sequestration?!

You’d probably say, “Huh?? Hold on, what is geothermal energy anyway, and how does it work?”

Geothermal is heat from deep inside the earth. Because heat is a form of energy, it can be captured and used to heat buildings or make electricity. There are three basic ways geothermal power plants work:

  1. Dry steam plants: Uses high-pressured hot steam to turn generator turbines. Think “steam to turbines.”
  2. Flash steam plants: Uses high-pressure hot water to create steam to turn generator turbines. Think “water to steam to turbines.”
  3. Binary cycle power plants: Uses high-pressure hot water to heat another liquid, which then turns to steam and turns the generator turbines. Think “water to other liquid to steam to turbines.”

(Click here for great diagrams of each of these geothermal energy production methods.)

“And what about carbon sequestration too? What’s that and how does it work?”
Carbon Sequestration: This nifty diagram illustrates both terrestrial and geologic carbon sequestration pathways.  Bonus!
Carbon Sequestration: This nifty diagram illustrates both terrestrial and geologic carbon sequestration pathways. Bonus!Courtesy Department of Energy

Carbon sequestration includes carbon (usually in the form of carbon dioxide, CO2) capture, separation, transportation, and storage or reuse. Plants, which “breathe” CO2, naturally sequester carbon, but people have found ways to do it artificially too. When fossil fuels are burned to power your car or heat your home, they emit CO2, a greenhouse gas partially responsible for global climate change. It is possible to capture those emissions, separate the bad CO2, and transport it somewhere for storage or beneficial reuse. CO2 can be stored in under the Earth’s surface or, according to Martin Saar’s research, used in geothermal energy production.

Alright. We’re back to Professor Saar’s research. Ready to know just how he plans to sequester carbon in geothermal energy production?

It’s a simple idea, really, now that you know about geothermal energy and carbon sequestration. Prof. Saar says geothermal energy can be made even greener by replacing water with CO2 as the medium carrying heat from deep within the earth to the surface for electricity generation. In this way, waste CO2 can be sequestered and put to beneficial use! As a bonus, CO2 is even more efficient than water at transferring heat.

But don’t take my word for it. Come hear Professor Martin Saar’s lecture, CO2 – Use It Or Lose It!, yourself during the Institute on the Environment’s Frontiers on the Environment lecture series, Wednesday, October 27, 2010 from noon-1pm.

Frontiers in the Environment is free and open to the public with no registration required! The lectures are held in the Institute on the Environment’s Seminar Room (Rm. 380) of the Vocational-Technical Education Building on the St. Paul campus (map).

A major earthquake (magnitude 7.0) has struck near Christchurch, the second-largest city in New Zealand. Early reports describe extensive damage, but few injuries.

Wonder what magnitude really means?

Apr
16
2010

Tracking worldwide earthquakes: Here is a map showing the epicenters of worldwide earthquakes over a 35-year span. No wonder it seems like earthquakes are happening all over the globe.
Tracking worldwide earthquakes: Here is a map showing the epicenters of worldwide earthquakes over a 35-year span. No wonder it seems like earthquakes are happening all over the globe.Courtesy Wikipedia
Geology may not be the "sexiest" of sciences, but when it gets cranked up, it can really make its presence known. And we've had a very interesting run of geological news in the past few months. The recent focus on earthquake matters is really summed up well in this commentary piece by Craig Childs of the Los Angeles Times.

Just in case you don't click the link, here are a few important notes from the piece to keep in mind while you're trying to figure out if the world is indeed coming to an end:

• With population increasing across the globe, more people are living in more hazardous regions.

• With our explosion of communications, we're hearing about earthquakes more often and in more depth.

• Since records have been kept on seismic activity, we know that about 50 earthquakes are recorded every day. Annually, the Earth averages 17 major earthquakes (7.0 to 7.9 on the Richter scale) and one doozy (8.0 or higher). The activity we've been seeing this year fits into those numbers so far.

Here are a few more items to points to take home regarding the recent geological frenzy:

Latest Chinese earthquake

As of Friday midday, the death toll in the China earthquake had climbed to over 1,100. While the devastation is much like the quakes in Haiti and Chile, the quake's cause, we're learning, was different.

Not all earthquakes start the same way. While most at the result of interactions between Earth's tectonic plates, this week's earthquake in China was different. It was an "intraplate" quake contained within an individual tectonic plate. Here's a full explanation. Basically, a quake occurs along a smaller fault that forms inside the plate, which is caused by other plates pushing on that plate's edges.

The New Madrid Seismic Zone in the central U.S., stretching from Arkansas to southern Illinois, is another example where "intraplate" earthquakes occur. On average, there's about an earthquake every-other-day in that zone, but they're very mild. But a large quake in the zone can spread damage over a much larger area.

Volcanic ash aloft: This aerial photo shows a volcano in Alaska spewing ash into the air in 2006.
Volcanic ash aloft: This aerial photo shows a volcano in Alaska spewing ash into the air in 2006.Courtesy Wikipedia

Iceland volcano update

Iceland's Eyjafjallajokull volcano continues to erupt and its ash continues to interrupt airline travel. Geologists have no idea how long the eruption might last. Back in 1821, the volcano erupted for several months. And the larger neighboring volcano, Katla, has not erupted yet. Typically it follows after Eyjafjallajokull's initial eruptions, and geologists say if that happens again, Katla could send out even greater amounts of volcanic ash.

Iceland may be the Rodney Dangerfield of Europe – it just doesn't get no respect – but geologically it's at the epicenter of world attention these days. Iceland is in a volcano hot zone and an eruption Sunday of the volcano Eyjafjallajokull has garnered a lot of attention. Historically, every time Eyjafjallajokull erupts, the larger volcano Katla erupts soon after.

Below is aerial video shot by the Iceland Coast Guard showing Sunday's eruption. Stay tuned to see if there are more eruptions to come. Past eruptions of Katla, with lava and gases passing through Iceland's ice sheets, have created toxic smog that have damaged crops and sickened people in the British Isles. Here's the full AP report.

Nov
05
2009

A new exhibit featuring artwork by geologists, other earth scientists, and geoscience students is being presented this month at the Two Wall Gallery on Vashon Island, Washington.

Fabric art
Fabric artCourtesy Linda Hope Ponting
Geo sapiens, Geology and Art” could be the first-ever show of its kind, and will feature artwork from entrants from such places as the US, Canada, Great Britain, France, Australia, New Zealand, and Okinawa. Artwork includes sculpture, painting, photography and fabric art.

Block print
Block printCourtesy Greg Wessel
Curator Greg Wessel, who co-owns the gallery - and is also a working geologist - put out a call for submissions to geo-science websites and magazines.

Meteor Crater
Meteor CraterCourtesy Mark Ryan
"There is a lot of potential to generate works of art that exhibit the wonder and beauty of nature,” Wessel said. “Most geologists take a lot of photos, for example. But in addition, I'm looking for connections both in the brains of the geologists and in their conscious application of geologic themes to the creation of artworks."

Stone Sculpture
Stone SculptureCourtesy Bill Laprade
Wessel received nearly twice as many entries than his small gallery can hold but he promised to show as many pieces as possible. And I’m happy to report that a photograph by yours truly is included in the exhibit.

Geo sapiens, Geology and Art” opens tomorrow and runs though November. Vashon Island is located in Puget Sound about 8 miles from Seattle.

AAPG Explorer article
More Geo sapiens info

Alfred Wegener birthday

by Anonymous on Nov. 01st, 2009

Alfred Wegener: Greenland, 1930.
Alfred Wegener: Greenland, 1930.Courtesy Public domain
Today is the birthday of Alfred Lothar Wegener, the scientist who first developed the theory of continental drift. Wegener was born in 1880, schooled as an astronomer, and became interested in climatology and meteorology. When he noticed how the shapes of some continents fit nicely into the forms of others, (such as how South America fit into Africa), he proposed in 1915 that they had once all made up a supercontinent he called Pangaea, and later drifted apart. Similar rock strata and fossils found in coastlines of distant continents seemed to corroborate his theory, but Wegener was unable to come up with a mechanism that would cause such movement, so his theory lay dormant, mostly spurned and unaccepted until the 1950's when new geological evidence regarding plate subduction and sea-floor spreading came to light. Wegener's theory of continental drift is the basis for present-day theory of plate tectonics. Unfortunately, Wegener didn't live to see his theory gain acceptance. He died tragically sometime in late 1930 while on a meteorological expedition to Greenland.

More about Alfred Wegener

Two volcanoes in Congo, Africa, are exhibiting signs of erupting soon. Here are the details. Half a million people live with in the impact zone of a major eruption. Lava flows from an eruption seven years ago from one of the volcanoes killed about 100 people.

Mar
27
2009

Ever wonder just why the Red River seems to flood so regularly? North Dakota State geology professor Don Schwert says:

"Fargo and Moorhead sit on one of the flattest surfaces on Earth. It's the lakebed of what was a gigantic lake at one time--glacial Lake Agassiz. Lake Agassiz was here from about 12,000 years ago to about 9,000 years ago, and after the lake drained, it left behind sediments that formed this flat surface. These sediments form the basis for wonderful soils, but they form as well this flat surface off of which water is reluctant to drain. And so the Red River is doing the best it can in trying to process water across this flat landscape. But what happens is that, during times of floods, as we're having now, water spills out of the channel and onto the bed of the old glacial lake, and the glacial lake sort of reappears."

"The Red River Valley is unusual compared to other river valleys around the world. Most river valleys are effectively carved by the rivers themselves (if you think about the Colorado River, or the Mississippi River). But the Red River Valley, the river itself couldn't have begun to flow until glacial Lake Agassiz drained about 9,000 years ago. Now the importance of that statement is that we normally measure the ages of rivers around the world in terms of hundreds of thousands of years, millions of years, maybe even tens of millions of years, and here we have a river that began to flow about 9,000 years ago, and began to flow across this flat surface. It hasn't had time and it hasn't had the energy to carve any kind of meaningful valley. The lakebed of Lake Agassiz becomes the effective floodplain in times of flooding, and the river spills out onto the old lakebed, and glacial Lake Agassiz kind of reappears."

"One of the problems with the Red River is that floods can't be confined, in an engineering sense, by means of dams. A dam crosses a river valley, and water builds up behind it, and it can store water. Well, here we have this expansive surface: the feature we call the Red River Valley is actually the lakebed of Lake Agassiz, and in some places it's 60 or 70 miles wide, and there's no way, really, of effectively managing water in terms of reservoir storage in the southern Red River Valley.... There's really no other river in the world like it."

"[The Red River flows north, which is not really unusual.] But it does have a consequence: typically, in the Red River Valley, a spring thaw begins in the southern portion of the valley. So waters are released in the southern portion of the valley and begin slowly to work their way northward at about the same pace, perhaps, as the the thaw is working its way northward along the valley. So as waters are being delivered northward, waters are also being released in portions of the valley. And everything's kind of clumping together and keeps on building up as the river and its waters and the flood are processed northward. So it becomes very problematic, particularly in the northern portion of the valley: massive, shallow, expansive floods. In 1997, in portions just north of the North Dakota border on into Manitoba, one could measure the flood, in terms of width, at 60 to 70 miles wide. An Ohio River flood might be 1,000 yards. Here it's 60 to 70 miles wide, so it's an incredibly expansive flood. It's sort of a rebuilding of the old lake, in that sense."

"Urban development, or urbanization, is a problem worldwide in terms of helping to exacerbate flooding of rivers. If we think about the path of a raindrop before human settlement, that raindrop would take a long time being delivered into the main drainage. But here in Fargo-Moorhead, or cities elsewhere around the world, we can process that raindrop in a matter of minutes or a couple hours in there, and it's immediately delivered into the channel. When we think about parking lots and shopping malls, housing and driveways and streets, highly efficient drainage ditches or drain tiles in agricultural fields--all of that is processing water, all of that is accelerating the delivery of water into the main stem drainages."

(You can listen for yourself at the link above.)

Glacial Lake Agassiz and the Red River Valley: Not all of this huge area was underwater at one time, but Lake Agassiz was bigger than all the Great Lakes put together and held more water than all the lakes in the world today.
Glacial Lake Agassiz and the Red River Valley: Not all of this huge area was underwater at one time, but Lake Agassiz was bigger than all the Great Lakes put together and held more water than all the lakes in the world today.Courtesy Figure 1-2 from A River Runs North, by Gene Krenz and Jay Leitch, Red River Water Resources Council (1993)

Lake Agassiz
Lake AgassizCourtesy North Dakota Geologic Survey

More interesting resources:

Minnesota Public Radio posted this cool time-lapse, shot over 20 minutes, of sandbag operations at the Fargodome on Wednesday, 3/25.

One more interesting/worrisome thing to consider: the area of Canada once covered by the glaciers and glacial Lake Agassiz is still slowly rebounding after being pressed down by the weight of the ice. According to the New York Times,

"For the north-flowing Red River, that means its downhill slope, already barely perceptible, is getting even less pronounced with each passing year, adding to its complexity, and its propensity to flood."

Nov
30
2008

Diamonds from Canada: Click on the mafic link for more photos related to hunting for diamonds near the Arctic Circle.
Diamonds from Canada: Click on the mafic link for more photos related to hunting for diamonds near the Arctic Circle.Courtesy mafic

Understand geology

Chuck Fipke, with a degree in geology, was hired out of college by Kennecott Copper to look for gold and copper. About 8 years later Superior Oil hired him to look, not for metals, but diamonds. A Superior geologist named John Gurney, discovered that the presence of chromite, ilmenite, and high-chrome, low-calcium garnet within kimberlite predicted the finding of diamonds. Fipke, combining what he understood of Gurney's work with results coming out of Russian labs and his own skills with field sampling, started looking for diamonds in Canada.

Using what you know, start looking

With Superior's backing, he teamed up with a geologist and pilot named Stewart Blusson, formed Dia Met Minerals, and headed north.

Drill for samples and work "upstream"

De Beers geologists were already looking for diamonds in Canada. Fipke knew that glaciers pushed everything southward so he looked further north. He also noticed that the further North he went the less worn were the edges of the diamonds.

Fipke got a helicopter and flew back and forth over the Arctic Circle, using a magnetometer to track variations in magnetic field that would suggest kimberlite. After thousands of miles and hundreds of hours in the air, he found a promising site near Lac de Gras, a barren world of lakes and rock and muskeg a few hundred miles outside the Arctic Circle.

Keep looking, don't give up

He'd been surveying for eight years. He hadn't found a single diamond. Superior had abandoned the diamond business. Dia Met's stock was trading at pennies a share.

I worked hard, and I mean really hard. I worked seven days a week from 8 am until 3 am. Every day. We drilled and drilled all winter when it was dark and the windchill was 80 below. Everyone thought I was crazy.

Become a billionaire

In 1991, Fipke found a kimberlite pipe (buried under 30 feet of glaciated sediment) with a concentration of 68 carats per 100 tons — the first Canadian diamonds ever found. Shares of Dia Met rocketed to $70.

Chuck Fipke had partnered with mining giant Broken Hill Proprietary Company (now BHP Billiton) to get the diamonds out; BHP opened the Ekati mine at Lac de Gras in 1998. Soon Dia Met's 29 percent share of the mine was worth billions. Fipke would go on to sell his chunk to BHP for $687 million, retaining 10 percent ownership in the mine, worth another $1 billion.

Diamonds from Canada now account for 10 percent of all diamonds by carat sold in the world. The country's four working mines produced 17 million carats in 2007.

Source: How a Rogue Geologist Discovered a Diamond Trove in the Canadian Arctic Wired

Three volcanoes in South America have become quite active. Here's a video report from National Geographic. One volcano in Ecuador is so active that it suspended flights into Quito's airport for a while.