Archive for July, 2019

Team Geochemistry’s Grand Finale

July 31st, 2019

Wooster, OH – Team Geochemistry wrapped up their grand adventure last week. The summer research experience left us with fond memories of trips to Dickinson College and Iceland, knowledge of lots of new analytical techniques, and many new friendships, not to mention the important findings from a critical field site that we’ll be presenting at the December meeting of AGU. Here are some parting thoughts on our bittersweet ending from guest blogger Kendra Devereux (’21):

After returning from Iceland, team geochemistry has been hard at work prepping their samples. In just two short weeks, all 23 whole rock samples from the field have been cleaned, powdered, sieved and turned into fused glass beads and pressed pellets.

Hannah, Layali, and Kendra spent the first week back from Iceland sieving their powdered samples.

Layali happily sieving!

Hannah happily sieving!

Hannah finished her time for the summer last week and is busy moving to Florida with her family, leaving Layali and Kendra on their own for their last week of work. Layali and Kendra spent this past week making 23 fused glass beads and 23 pressed pellets

Pressed pellets and glass beads are all ready to be analyzed with the XRF next week!

As a celebration of all their hard work, Dr. Pollock, Layali, and Kendra enjoyed “Taste of Wooster” downtown on Thursday night.

A delicious chocolate marshmallow whoopie pie from The Blue Rooster.

After 8 weeks together, team geochemistry have said goodbye until the 2019-2020 school year begins!

Wooster geologists working at site of first glacier memorial in Iceland

July 23rd, 2019

Iceland – Big news this week as researchers dedicate the first-ever monument to Okjökull glacier, memorializing the first Icelandic glacier to lose its glacier status to climate change. Ice loss in Iceland is dramatic; researchers expect all of Iceland’s glaciers to go extinct in the next ~200 years, with drastic changes to Icelandic culture and economy. As the ice retreats and reveals the underlying land, scientists can investigate ancient volcanoes that erupted thousands of years ago under the glacier. Wooster geologists were with a team from Dickinson College on the scene of Ok volcano this summer, exploring a glaciovolcanic ridge that is now exposed on the southeast flank of Ok volcano.

View of Ok shield volcano from the south. Bræðravirki is the glaciovolcanic ridge on the southeast flank of Ok volcano. (Photo Credit: Hannah Grachen)

Another view of Bræðravirki ridge from the east. The summit of Ok volcano is off of the photo to the right. (Photo Credit: Hannah Grachen)

Most of Bræðravirki ridge is made of yellow ash that was erupted explosively and has been consolidated into a rock called tuff. The patterns in the rock tell us about how it formed. (Photo Credit: Hannah Grachen)

The tuff has a distinct yellow color that forms when the volcanic ash reacts with hot water. We also see glassy black rocks in the ash that we think are volcanic bombs, which form when lava is ejected violently during an explosive eruption. (Photo Credit: Hannah Grachen)

The ridge also has irregularly shaped bodies of massive rock. These are light gray and extremely hard, with a unique pattern of cracks that forms as the molten rock cools and solidifies. We think these are fingers of magma that get injected into the growing ash pile. (Photo Credit: Hannah Grachen)

Ok volcano and Bræðravirki ridge give us the opportunity to explore past climates and interactions between volcanoes and glaciers, helping us predict what might be in store for Iceland and other ice-covered volcanoes across the world. (Photo Credit: Hannah Grachen)

Look for us at the December 2019 meeting of the American Geophysical Union in San Francisco, CA (USA), where we will be presenting our findings from Bræðravirki ridge.

Summer undergraduate researchers travel to Iceland to explore volcanoes

July 19th, 2019

Iceland – In our last post, Team Geochemistry was getting ready to head to Iceland for some field work on volcanoes. Our goals were to map and sample volcanoes that erupted under glaciers, which have since retreated, exposing the pillow lavas and ash that formed when lava met ice. We met up with a research team from the Dickinson College Earth Sciences Department, and also brought Dr. Shelley Judge, Wooster’s structural geologist. Together, we collected over 30 samples, took 1000s of photos, flew the drone for 8 hours, and made 100s of structural measurements. Overall, it was a successful and productive field season, with some laughs along the way! Layali Banna, member of Team Geochemistry (and basalt goddess), describes their field experience.

[Guest blogger Layali Banna] Last week, team geochemistry went to Iceland. We met up with some old friends there, but we met some new ones as well. In total there were ten of us and we were ready to take Iceland by storm.

All of us walking along Undirhlíðar (from left to right: Phoebe, Dr. Edwards, Marisa, Dr. Judge, Dr. Pollock, Kendra, Layali and Ethan; Hannah Is behind the camera taking the photo.)

After a long day of flying we decided to mostly take it easy, just doing a short walk around a nearby quarry to learn more about what we will be looking for out in the field.

Dr. Pollock posing for her glamour shot.

The second day was much different though – we spent almost all day out on Hannah’s site collecting samples for her project at Bræðravirki ridge. Divided into two teams, one group walked the ridge collecting samples, while the other group used a drone to map the ridge. This was a prime time up at the ridge since there was no snow cover, unlike past years where the gullies were hidden by snow, allowing us a great look at it without anything in the way.

Kendra smiling with Prestahnúkur in the background, which is a rhyolite volcano.

A gulley on Bræðravirki that was buried in snow during past years was now accessible for sampling.

Our third day in Iceland after that long day in Bræðravirki we spent the morning inside working on our field books and collecting some data, making observations on our samples.

 

Everyone working together to look through all the samples we had collected the day prior.

The latter half of the day we surveyed Undirhlíðar and ended up goofing around a bit at a certain spot called the bowl.

Kendra and Marisa trying to figure out how they are going to climb up the side of the bowl.

After our half day we returned to Undirhlíðar. This time we were split up into three groups all doing different things in separate areas. One group mapped with drones, another analyzed and mapped deformation bands, taking samples and pictures of the bands, and the last group went and took samples for Marisa’s project.

A beautiful, thick, glassy dike found on Undirhlíðar.

Time for a snack break! Marisa is eating a nutritious energy boosting cookie.

Finally, on our last day in Iceland everyone was given a free day to do what they want, exploring some of the natural wonders the island has to offer as well as touring the capital of Iceland, ReykjavÍk.

Hannah finally getting her photo taken instead of her always being the one taking them at Krýsuvík thermal zone.

The group stopped for some famous Icelandic street dogs in ReykjavÍk, Kendra is ready to dig in.

All too soon it was time for us to pack our bags and say goodbye to our friends and Iceland. It was time to head back to Wooster and work on the samples we collected in the lab.

 

A continental heat wave won’t stop Wooster Geologists …

July 18th, 2019

… but it will slow us down! Today Nick Wiesenberg, our excellent departmental technician, and I took a short day trip to southeastern Indiana to collect fossils for my upcoming Paleoecology course. It was in the middle of what may be globally the hottest month on record, as well as the start of a long extreme heat event in North America. It was plenty hot and sticky, but the fossils were toasty warm and inviting. Nick is shown above on my favorite outcrop of the Upper Ordovician Whitewater Formation along US 27 (locality C/W-148). It is no doubt the most photographed section on this blog. [Update: July 2019 was indeed the hottest month ever. Sadly, I’m sure it will later be superseded by a still hotter one.]

Here is the same scene in March 2017 with Wooster students Luke Kosowatz and Matthew Shearer. Note the white icicles!

And here am I testing the concept that baggy clothes are cooler. I’m standing on an outcrop of the Upper Ordovician Liberty Formation exposed along IN 101 (locality C/W-149).

Nick and I were successful in filling a box with beautiful fossils for lab exercises, and we were happy to retreat to the air-conditioned car for the four-hour ride back home!

Tree Corps Visits the Tree Ring Lab

July 11th, 2019

Tree Corps visits the Wooster Tree Ring Lab. Tree Corps is a program run out of the Holden Arboretum designed to provide training to the arboriculture workforce in the Cleveland Area. It is funded by the Cleveland Foundation and this is the second year the group has visited Wooster. We all learned a lot from each other and everyone got to core some of the oaks on campus with the end of assessing tree health and age.

The group discusses the information that can be derived from the tree-ring record. This black oak shows outward signs of deterioration, however inside it is solid. In terms of management, the location of the tree with respect to foot traffic,  balanced with other pressing tree issues across campus, all need to be considered when assessing the possible removal of this tree.

Nick extracts a core from the oak and discusses the reasons for the various discolorations of the wood.

Josh Charlton (class of 2019, purple shirt) was visiting the lab and offers some advice in coring – thanks Josh for your help.

 

 

 

 

 

We also spent some time coring pin oaks on campus. Great fast growing trees – the group mounted up the cores and analysis of the tree rings is underway. Thanks to Tree Corps for making it down to the lab, we look forward to following the future progress of the group in arboriculture.

The week leading up to international field work

July 6th, 2019

Wooster, OH – In the week leading up to field work, Team Geochemistry was frantically trying to “put out fires” and clean up loose-ends.

The “fires” started first thing Monday morning, when a leak in the geochemistry lab caused the ceiling to collapse. Fortunately, the students and cleaning staff were quick thinking and all ended well.

Next, we tried to wrap up our petrology classification project, which involved lots of microscope work. Classifying minerals in the microscope was more challenging than we expected, and we still have more work to do when we return from the field.

Finally, we had to gather our field gear, double-checking that we had everything we needed. Undoubtedly, there will be something that we forgot.

Even with the frantic pace of the week, we still made some time for an ice cream (or two!). It was the Fourth of July holiday, after all.

Team Geochemistry in currently en route to Iceland for some field work. We’ll be reunited with Marisa, our teammate from Dickinson College, along with Dr. Ben Edwards and three other Dickinson students. Dr. Shelley Judge, from Wooster, is also joining us for this field excursion. Look for updates from the field late next week!

Columbia Bay’s Emerging Landscape

July 5th, 2019

I had the distinct pleasure of working in Columbia Bay, Alaska for ten days along with researchers Drs. Tim Barrows from the University of Wollongong – Australia, Peter Almond of Lincoln University, New Zealand, and Wooster’s own, Nick Wiesenberg.

Tim with the retreating West Branch glaciers in the background.

Peter with the spectacular backdrop of the calving glaciers in the West Branch.

Nick reclining in the old growth mountain hemlock forest overlooking Lake Terentiev – sure to be a classic tree-ring record of past climate.

Logistic centered on travel in an aluminum skiff. Captain Peter took the helm and Nick kept us off the ice, which on some days was easier than others (see below).

One of the primary objectives was to sample boulders on moraines and bedrock surfaces to determine the timing of glacial changes in Columbia Bay. Tim and Nick sampling for cosmogenic dating on a surface outside of the Little Ice Age limit.

Sampling a boulder that is well vegetated. Note the bug nets – we did notice the bugs.

Peter is a soil scientist and he dug pits on most surfaces we studied; here a well-developed spodosol is revealed. It had been years since we have dug soil pits and I was amazed. Future trips will include soils work and a stout spade.

The geomorphology was interesting at all turns – here is a beach berm that likely formed when the glacier, now 25 km away, was nears its maximum during the early decades of the 20th century. Note the trees growing on the surface; a nice project for dendrogeomorphology.

In 1909 Tarr and Martin observed the then expanded and soon to be advancing Columbia Glacier – the top panel is their photograph taken in 1909 with the Columbia Glacier looming over a remanent forest. The lower panel is a photo from the same location in June of 2019.

We were also fortunate to work on Heather Island (great thanks to the Tatitlek Corporation for permission to visit the Island). The upper panel is the Tarr and Martin 1909 photograph from near the summit of Heather Island and the lower photograph was taken in June of 2019.

The photo above was taken in June of 2014 – note the location of the calving glacier in the background relative to the photo below taken in June of 2019.

The active ice in the west arm of Columbia Bay is now 4 tributary glaciers – a dramatic change in less than five years.