Archive for July, 2011

Return to a Silurian crinoid forest

July 5th, 2011

KURESSAARE, ESTONIA–Today our Wooster Geology team visited a favorite outcrop of mine: the Äigu Beds of the Kaugatuma Formation exposed on the northwestern shore of the Sõrve Peninsula on Saaremaa. These are Late Silurian (Pridoli) limestones with a great abundance of crinoid fragments — so many that they are locally called “ringstones” (see the above image of a crinoid stem and isolated ring-like columnals). Palmer Shonk (’10) studied this outcrop for his Independent Study thesis. We returned here today to collect more field data so that Palmer, Olev Vinn, Bill Ausich and I can write a professional paper on the depositional system and paleoecology.

The limestones show significant storm beds made of skeletal debris, especially the crinoids but also corals, stromatoporoids, bryozoans, brachiopods and trilobites. The most remarkable aspect of this exposure is the presence of an in situ crinoid “forest” of holdfasts (the part of the crinoid that holds it to the sediment). Our job today was to find out more about the non-crinoid fauna since Palmer and I have already mapped out the crinoid holdfasts. We hope to soon publish a rare look at a Silurian crinoid community essentially preserved in place.

The Kaugatuma outcrop on the Sõrve Peninsula of Saaremaa. This was a Russian amphibious landing zone in 1944. You can bet you’ll read more about that story later!

The star-shaped fossil with the hole in the center is a crinoid holdfast in place at Kaugatuma. There are dozens of these scattered across the outcrop. The crinoid is Enallocrinus. The hole in the center is the hollow lumen of the crinoid stem.

Nick found this calyx of another crinoid known as Eucalyptocrinites. Such well preserved calices are rare.

Nick also found this very nice trilobite pygidium (tail piece). It is preserved well enough that we can probably later identify it to the genus level.

Last day at Undirhlíðar

July 4th, 2011

HAFNARFJORDUR, ICELAND: Guest blogger: Lindsey

Today we wrapped up my field work in Undirhlíðar by double-checking our annotated photos and a brief tour of the West wall to confirm our hypothesis that the olivine rich pillow unit continued consistently along this section. We had a quick lunch before heading off to Krysuvik, about 30 minutes south of where we were staying to see some sights we had read about yesterday but had unfortunately missed on our excursion. We first came to Kleifarvatn, a large lake with black sand beaches with a legendary worm-like monster residing in its depths. We spotted it immediately:

Nessy's cousin

We then traveled a little further to Seltun, a large geothermal field seated at the base of a ridge. This area was drilled to supply energy to nearby Hafnarfjordur, but a silica build up in the borehole caused the area to explode in 1999. Another interesting thing to note about this area is the legendary Hverafugl, or “hot spring bird” that supposedly hops into a geothermal vent to hide from humans when they approach. People don’t really believe they exist anymore as a picture has never been taken of one, but older generations believe the birds are apparitions in the steam that represent spirits of the dead. We did not see any Hverafugls, they were clearly hiding.

A geothermal vent at Seltun geothermal field

I decided to stick my hand in to see if it was hot- it was. Can you imagine what the vikings must have thought when they first saw water boiling up out of the ground?

Theory to practice

We then continued a little further to Graenavatn, a strange green lake that is supposedly an old explosion crater. The green color is due to the minerals from the nearby geothermal field as well as algae.

Graenavatn

At this point we turned around and came back as we had seen a lot of the peninsula yesterday, and seeing as we haven’t shared the sights on the blog yet, we thought our Estonian colleagues would appreciate seeming some coastline with real cliffs- no offense Nick, your study site is really cute! We started in Hafnarfjordur and ended in Rekjavik (bad map) but saw some incredible things along the way!

The first stop was at Leif the Lucky’s bridge, a spot where you can travel across the bridge from the North American to the Eurasian plate. It was so cold, rainy and windy!

Travis and I halfway between two continents

Stop number 2 was Valahnukur, a coastal area with dramatic black cliffs and powerful waves. We added Icleandic horses to our wildlife list as some were in a field right off the road to the ocean.

Windblown Icelandic horses

The cliffs hosted a large population of seabirds, the most famous of which was the Great Auk, a now extinct breed of flightless bird. The last Great Auk was apparently shot, killed and eaten on a small island 10 km off the coast. Some countries try breeding programs, Iceland has a BBQ.

The Great Auk statue at Valahnukur contemplates its demise

Our last stop of mention yesterday was in Gunnuhver, a geothermal area named after Gunna-a legendary witch/vengeful woman depending on the guide book you read. The story that I like best is that Gunna didn’t like her neighbor, so killed him and his wife. The other villagers instructed her to hold on to a knotted rope, she complied and they then dragged her into the geothermal springs where she perished. We all thought that this story was missing some explanations and was probably literally translated from Icelandic.

Gunna's grave

After a long afternoon of sightseeing, we headed back home to cook dinner at our cozy guesthouse.

Happy Fourth of July to our Estonian colleagues in return! Today we found BBQ sauce and corn-on-the-cob at the grocery store and had a lovely celebratory dinner!

Travis makes liberal use of the lighter fluid

Perhaps if we had been able to combine the Estonian weather with our Icelandic dinner we would have had a pretty good approximation of an American Fourth of July!

Off to Travis’s study site in Blonduous tomorrow.

Back to the Big Island for the Fourth of July

July 4th, 2011

KURESSAARE, SAAREMAA, ESTONIA–The Wooster Geologists Estonia Team today braved the Baltic Sea again and took a ferry from the island of Hiiumaa to return to their previous field sites on the island of Saaremaa. We worked at Soeginina Cliff on the western coast (shown above) to finish up Nick Fedorchuk’s Independent Study field research on the Wenlock-Ludlow (Silurian) erosional sequence. It was a fun day because we now have hypotheses to test about these rocks and fossils. More on those later.

The above rock shows an advantage we have studying exposures on rocky coastlines. The waves erode blocks of limestone from the cliff and polish them up on the boulder-strewn beach. We can thus see our rocks in three dimensions rather than just the flat cross-section we would normally have. The trick, though, is to know from where in the section the boulders were derived!

We found some excellent sections through the numerous oncoids in our outcrops as well. We saw that many are formed around gastropod (snail) shells — very much like a Jurassic version I recently described as one of Wooster’s Fossils of the Week.

Tonight we will celebrate the 4th of July with a pizza dinner in downtown Kuressaare. It is as close to American food as we can get here. On this holiday we salute the Wooster Geologists Iceland Team also far from home on the front lines of science!

Tubes, Trolls, and the West Wall

July 4th, 2011

HAFNARFJORDUR, ICELAND- [guest bloggers Travis and Lindsey]

We only spent about 2 hours in Undirhlíðar yesterday due to the gale force winds that sent basalt shrapnel flying into our faces, in particular our eyeballs. It wasn’t raining luckily, as raindrops probably would have been lethal at that wind speed. We made an awesome discovery though on the Northeast wall- A lava tube! We were climbing up a talus pile when we noticed the hole leading down into the wall.

Travis is either falling in or being dragged in by a troll.

Here is what Travis and I hypothesized:
1. Troll den
2. Center of the earth
3. Dinosaurs
Unfortunately, Dr. Pollock didn’t let Travis get into the lava tube, though he tried his best to convince her. Reasons Travis thought getting inside the lava tube was a good idea:
1. We would find the base of the pillow unit
2. She would become the most famous geologist of all time
3. Dr. Wilson would let me
Reasons Dr. Pollock said no:
1. Because I said so

Travis may be convinced not to go into the lava tube but Lindsey still clings to the idea.

We then moved on to the West wall and found basalt that looked drastically different than anything we had found in the East wall.

The West Wall, Undirlihdar Quarry.

Sizable olivine and plagioclase crystals were in all of the rock units we saw in the Southern end of the West wall.

 

Large olivine phenocrysts within the basalts of the west wall!

Today is our last day of field work in the quarries, we’ll keep you updated on our continued adventures.

Saying goodbye to the little island of Hiiumaa

July 3rd, 2011

KÄINA, ESTONIA–Today we had our last visit to our Silurian quarry working site (where I photographed the Paleofavosites coral fossil above, which by the way was preserved upside-down in the sequence), and then we had lunch in the town of Kärdla overlooking the Baltic. Tomorrow we take the early morning ferry back to the larger island of Saaremaa where we resume fieldwork. Here are a few last photographs from Hiiumaa.

The other Silurian outcrop on the island: Kallaste Cliff. A bit overgrown, we think.

Some purple flowers found in the woods near our field site.

Yellow flowers in the quarry itself. I do know the one on the left is a daisy!

Whitish flowers and then a moth-covered thistle. I photographed this Six-Spot Burnet moth earlier, but three on one flower deserved another image. I'm sparing you the photos of them mating!

Our hotel on Hiiumaa. For most nights we were the only ones there. The students said it reminded them of "The Shining".

A walk to the sea after lunch in Kärdla. We have enjoyed this weather very much.

Wooster’s Fossils of the Week: Nummulitid foraminiferans (Eocene of the United Arab Emirates)

July 3rd, 2011

The Great Pyramids of Egypt are made primarily of a yellowish limestone. About 40% of that limestone is made of the fossil type pictured above. These are foraminiferans (single-celled organisms with shells) that lived by the countless billions during the Eocene (56 to 34 million years ago) in the Tethys Ocean. They are called Nummulites from the Latin nummulus, which means “little coin”. They have the honor of having been first described by the 5th Century BCE Greek historian Herodotus, who noticed them in the Pyramid stones. (He thought, by the way, that they were fossilized lentils.)

(From R.A. Lydekker (1894), Life and Rocks.)

If you slice a nummulitid test (what we call a foraminiferan shell) like a bagel, the inside is revealed to be a long spiral. The single-celled organism built the shell by progressively adding to this spiral, making the largest foraminiferan tests ever known, some over 15 cm in diameter. (Most foraminiferans have tests about the size of a pinhead.)

I collected our Wooster Nummulites during fieldwork with my colleague Paul Taylor near Al Ain in the United Arab Emirates. I thought at the time that I was picking up two species: a small one and a significantly larger one. I later learned that these are two versions of the same species. Nummulites reproduced alternately sexually and then asexually. This alternation of generations is seen today in many living foraminiferans, and we see an analogue in some plants like ferns.

Nummulitids are the stars of a strange story in paleontology. A British zoologist who was at the time assistant keeper of invertebrates at the British Museum (Natural History) wrote a book (The Nummulosphere, 1912) and a series of papers with the astonishing thesis that all rocks were actually made of foraminiferan tests — all rocks! Even basalt, granite and meteorites are organic in origin. The late Stephen Jay Gould told the tale of Randolph Kirkpatrick (1863-1950) memorably in his compilation of essays The Panda’s Thumb (Norton, 1980). Kirkpatrick’s work is well worth reading for his incredible arguments. (Lava, for example, is melted “siliceous nummulitic rock” recycled back to the surface.) The tortured logic to show the remains of Nummulites tests in igneous rocks is oddly entertaining.

“Fig. A [Plate XXI]. Section of rotten trachyte [a volcanic rock] permeated with sulphur from interior of upper crater of Tenerife, x 4.5. The coils of a much-blasted nummulite in perpendicular section are visible to the trained vision.”

 

Using the iPad in geologic field work-Part 2

July 2nd, 2011

HAFNARFJORDUR, ICELAND- Guest Blogger: Lindsey Bowman

Our Estonia-based colleagues certainly have an advantage when it comes to timely blog posts; lagging three hours behind we are now appearing redundant in our post topic! We too have been using the iPad 2 in the field, particularly today in Vatnsskarth quarry as the rain has turned into intermittent mist. As Dr. Pollock and Travis took notes in their classic Rite in the Rain field books, I trailed along behind and took photos and annotated directly in front of the outcrop they were sketching.

Annotating the East wall of Vatnsskarth

We found it incredibly useful to take the photo and be able to reference the wall directly in front of us, as subtle differences between columnar and pillow basalts are sometimes hard to see in a photo. We also struggled a little with the glare, but found that Iceland’s weather was actually advantageous as we never saw the sun today. Below is an example of a photo annotated in the field:

Base of the pillow ridge showing glacial sediment directly overlain by basaltic pillows.

However, some photos do require more detailed annotation later in the cafe over a latte.

Annotation of a photo taken previously in the field

Below is a photo from Undirhlíðar that I plan to use in some capacity of my I.S.:

Undirhlíðar- SE wall

We also wanted to share one of our equipment finds that leaves us worry-free about tossing the iPad into our day packs with basalt samples and other sharp or heavy objects. Below is the Otterbox case that we have on the iPad, which not only keeps it safe, but also acts as an easel-like stand for when we want to use the iPad on a flat surface.

Otterbox case leaves us worry-free about the iPad's safety!

We have been using the annotation app ArtStudio which we have found to be flexible and intuitive. We are using a Just Mobile AluPen with the app to make drawing easier; like Dr. Wilson, I have found the stylus helpful.

Stylus > Finger

Finally, to keep the iPad safe from the rain and mist, we have found that a gallon-sized ziploc bag works just fine.

Tomorrow we will head back to Undirhlíðar, since we finished in Vatnsskarth today. We are hoping for clear skies, but watching the mist blow through the quarry and across the rocky landscape today was beautiful. Dr. Pollock mentioned how easy it is to visualize Icelandic folklore and legends in weather like this, and honestly, imagining ghostly vikings emerging from the billowing mist didn’t seem all that far-fetched.

Using the iPad in geological fieldwork

July 2nd, 2011

KÄINA, ESTONIA–It is not yet one of my regular bits of field equipment, and I am certainly far from an expert with its use, but I can say a few things about the value of an iPad in geological fieldwork. This summer I have used it in Israel, Poland and Estonia and it has served me very well.

Despite the dramatic photos here, I have used my iPad2 mostly indoors. It is by far the most convenient field library I have ever had. Laptops are great for storing and displaying pdfs of papers and maps, but it just can’t beat the convenience of simple taps on the iPad screen to pull up astonishingly clear text and images. I use PDFReader Pro so I can easily zoom in and out on the screen with the classic Apple two-finger move. I add documents to this reader and others with Dropbox (recommended to me by Lisa Park), which has the advantage of syncing with all my other computers. (I seem to have more than a few now.) It has never been easier in a remote location to read documents and share them with students and colleagues. My trusty MacBook Pro seems terribly primitive for reading now.

Although I haven’t used them on this trip, I want to mention the excellent geological map programs of Integrity Logic. I have map programs for California, Utah and Ohio. Each comes with 25 layers, including bedrock geology, roads, mines, earthquake epicenters and much more. They are essentially GIS products for the iPad and iPod. I’ve found them most useful when traveling through (or flying over) a region I want to know more about.

For making typed notes indoors and out, I like the app Evernote because the typing is intuitive and it does a good job of correcting my mistakes. I would not use this for serious writing (I can’t yet break free from the laptop for that), it is good for quick notes and, astonishingly, audio recordings and photographs through the iPad camera. I can, if I want, easily talk about an outcrop to my iPad and have it archive my precious words. (I haven’t yet.)

I use Bamboo Paper for sketches in the field and with colleagues around the dinner table. It is great for outlining crazy ideas in six colors. As with Evernote, the results can be emailed from the iPad. (Although I must say, I haven’t made any such notes worthy of leaving the device!) By the way, for sketching I very much like the Boxwave Stylus rather than relying on my fat fingers.

There is a behavioral barrier I’ve had to overcome before taking my iPad into the field itself. Carrying this precious machine in my backpack along with hammers, chisels, water bottles and, eventually, bags of rocks seemed a bad idea. I have a protective cover for the screen, but no sealed box for the whole iPad. I know they’re out there, but I haven’t found one I like. Instead I seal it into a separate pocket as far away from hard, sharp and wet things as possible. So far, no problems, but I hesitate pulling it out in the wilderness with all those hazards for electronics. I’ll get more accustomed to it, I’m sure. (Although I still feel that way about my camera.) Of course, no one would use an iPad in the rain — another reason I don’t work in Iceland.

The most useful apps in the field are again PDFReader Pro for accessing documents downloaded through Dropbox, Evernote and Bamboo Paper. I have been experimenting with Sketchbook Express for taking photographs in the field with the iPad and then annotating them on the spot. It is a very useful way to remember something visual, and the images can be exported out through email. Again, none of these jottings are publication quality — they are quick notes to myself. There is much potential in this latter application for more sophisticated field observations and records.

Taking an image of an outcrop with the iPad camera and then annotating it with Sketchbook Express.

Example of an annotated field image. Not brilliant because it is intended for my own notes alone. (The blogger's dilemma.)

Finally, general iPad apps I like as a geologist include Disaster Alert (realtime maps of disasters around the world), Sunrise Clock (especially helpful when you’ve crossed significant amounts of latitude!), Google Earth (of course), Star Walk (for starry nights), various language translation programs (I try), and GW Mail (for Groupwise email accounts — easier than accessing through a computer).

Again, I’m just starting with the iPad so I know there is much I’m missing. It has not replaced my laptop (I can’t write blog posts with it, for example), so I’ve actually increased the electronics I carry around on trips. I had an awkward moment in the Tel Aviv airport when a security officer looked at my US cell phone, Israeli cell phone, iPod, iPad, Macbook Pro, and GPS and asked why I needed all these things! Indeed. The future no doubt will have some sort of iPad-like device that does it all.

Feel free to add information and ideas through the comments below!

(Photos courtesy of Rachel Matt.)

First day of field work in Undirhlíðar Quarry

July 1st, 2011

HAFNARFJORDUR, ICELAND: Guest Blogger: Lindsey Bowman

Today Travis, Dr. Pollock and I started our field work in Undirhlíðar Quarry. It was cold, windy and rainy- perfect for our new rain gear!

Geochemists at work

We started mapping the quarry walls in detail where Becky Alcorn ’11 left off, and made it along the East wall in about six hours. We observed some gorgeous pillow lavas, the most abundant formation in the quarry.

Pillow from the East wall

Undirhlíðar is much larger than I had originally imagined it (certainly a  grander scale than Estonian quarries). Here’s a great picture taken by Travis:

Undirhlíðar quarry wall under consideration by Dr. Pollock and Lindsey Bowman

To brighten up this post, I’d like to nod to the colorful and abundant flora of Iceland. Barren? I think not.

Nootka Lupin outside Undirhlithar

Wood crane's bill

The only fauna that we’ve seen besides seagulls are these unfortunate fish- species unknown.

Dried fish- yummy!

Finally, below is a video taken by Travis today to give you an idea of Undirhlíðar in 3D-

Tomorrow we head to Vatnsskarth to continue our field work!

Tiny bit of wildlife on Hiiumaa

July 1st, 2011

KÄINA, ESTONIA–This is a shout-out to our Wooster Geology colleagues currently working on the barren volcanic island of Iceland. We thought they might want a break from the bleak expanses of black basalt for a little color of wildlife from Estonia. The creature above, of course, is a grasshopper we found in our quarry today.

This colorful moth seems to specialize in the nectar of a common thistle here. It is a Six-Spot Burnet (Zygaena filipendulae).

A native bee on a daisy.

And delicious wild strawberries every day!

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