Welcome (back) to Paradise!

12 08 2009

Hello and welcome to the 2nd edition of VolcanoSummer – Hawai`i! This year brings a much shorter visit to the Big Island and a somewhat familiar agenda, with exciting new faces and places added for your viewing pleasure. I arrived in Hilo via Honolulu on Sunday and was promptly met by the excellent Dr. Mark Kurz of the Woods Hole Oceanographic Institute and his nephew, David Kurz. We acquired the soon-to-be Dr. Brent Goehring of the Lamont-Doherty Earth Observatory and made the familiar trek up to Volcano, Hawai`i. This is the town outside of Hawai`i Volcanoes National Park, where our research group has rented two lovely houses for the duration of our expedition. We settled in to discuss the trip and await the arrival of the remaining members of our science party, Dr. Joe Licciardi of the University of New Hampshire and Shasta Marrero and Michelle Hinz of New Mexico Tech. Check out our awesome group!

CRONUS-HI09 Group

Our group was assembled to perform calibration work for the CRONUS-Earth Project using Mauna Loa lava flows. CRONUS is an international effort by geoscientists to use cosmogenic isotopes in dating many types of geologic features around the world. You may be scratching your head and wondering what the heck a cosmogenic isotope is, so I’ll give you the short version. The sun continually bombards the Earth with cosmic rays, and when some of these rays strike the ground they interact with certain elements contained in the rock. These interactions cause the elements to change into a slightly different version of themselves known as an isotope. You may be familiar with the concept of Carbon-14 dating, where scientists employ analysis of an isotope of carbon in order to date how old something is. CRONUS uses similar concepts but with rocks instead of carbon-based samples.

We are here in Hawai`i as part of an effort to determine just how accurate cosmogenic isotope dating methods can be. We are sampling lava from flows that we already know the ages of, whether through Carbon-14 dating of burned plant material (charcoal) or from historical accounts. The samples will be sent to laboratories for analysis, and we’ll be able to clearly see how accurate this dating method is. The benefit of cosmogenic isotope dating is that we are not limited as severely as we are with Carbon-14, and much older ages may be obtained. Basically, I’m hanging out with a bunch of geochemists who are into travelling the world and ascertaining the ages of various geologic features such as lava flows and landslides. It’s all in the name of science!

Ok, so that’s the detailed stuff. Let’s move on to the part you’ve all been waiting for: pictures!

Lava Ball the First

In this photo Mark, Brent, and Shasta are debating the merits of sampling from this particular lava ball. They’re standing on a roughly 900 year old Mauna Loa a`a lava flow. Site selection is key to our undertaking, as anything that could shield the rocks from the cosmic rays will throw off the dating technique. Also, the surface that is selected for sampling has to be the rock’s original surface. Erosion wears rocks down, and that type of material loss would make the rock appear younger than it actually is since the sun’s rays would have bombarded the eroded surface for less time. Scientists also like to use site selection as a means to argue amongst themselves. (No scientists were harmed in the making of that joke, FYI.) In the foreground of the picture you’ll find a 6lb sledgehammer, which can be used for sample collection or warding off greedy competing scientists. In the back right of the picture you can see Kilauea’s summit plume, which repeat readers may remember from last year. The summit eruption is indeed still going, in case anyone was wondering.

Plume Backwards

Hurricane Felicia never materialized by HVO, but the typical tradewinds were affected enough to cause the plume to blow in the direction opposite its normal route. Seeing the plume is like having a giant (and intensely awesome) welcome mat rolled out in greeting. The vent has increased substantially in size since I left HVO last September, and it now spans approximately 130 meters. To put it in perspective, that’s larger than a football field. Amazing.

I’m about to fall asleep while typing, so this’ll conclude tonight’s post.

P.S. – It’s great to be back!

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Adventures in liquid hot magma!

12 08 2008

Ok, I’m lying a bit while referencing Austin Powers. I haven’t played with active lava…YET. Tomorrow we’re going to the active flow field and I’ll hopefully get to poke lava with a stick. Here are some pictures of the lava flows from Sunday to tide you over until I have an adventure to relate!

Here’s a lava pool on Kilauea’s flank called the Thanksgiving Eve Breakout (TEB) vent.

Here’s a flow issuing from TEB.

Bear in mind that these aren’t my photos, but rather pictures taken by one of our geologists on a helicopter overflight. I’ll have a much different perspective tomorrow…up close and personal, I hope!





This is my job?!

5 08 2008

Last Wednesday we went down to the southern part of the island to collect littoral cone deposits. My boss is collaborating with a University of Massachusetts-Amherst professor to prove the magmatic origin of these littoral cones. Essentially, there is a large amount of olivine in the deposits closer to the coastline. The lavas that have erupted near Mauna Loa’s summit are olivine-poor. There are different hypotheses about why this is, and we were sampling to test the different ideas. On with it, right?

Well, we off-roaded for about an hour after we left the highway. When we tumbled out of the truck, this is the view that greeted us.

Very, very nice. After a few minutes of wistful gazing, we headed off to find our littoral prey.

This section of the island has littoral cones all along the shoreline. They’re the distant hills in that picture. Here is a closer view.

We had to climb the cones, find likely samples, break them open with a rock hammer, see if they were glassy and non-stratified enough, and then fill a whole bag with similar samples. Essentially, I spent the day smashing rocks with a hammer. It’s really a fun activity!

Our lunch break afforded me the opportunity to take a few pictures. You need to click the last one to appreciate it fully.

To say the waves were stunning would be an understatement. Eating lunch on a beach while trying to scrape basalt chunks out from under my fingernails has to be one of the best ways to enjoy a sandwich I’ve ever attempted.

We collected samples from 6 littoral cones and then headed back to HVO. On the way we stopped by some petroglyphs and I was able to get a shot.

Sometimes I still can’t believe I’m a geologist. It’s incredibly hard work, but worth every second. I remind myself of that when I feel like whining about doing something difficult. Hard work does have its rewards, and that’s why I’m working my butt off here in paradise.





Everything except for poking it with a stick.

24 07 2008

Tonight after normal work hours I was trained how to monitor the vent at Halema`uma`u. Ever since the caldera explosions earlier this year, HVO has had staff members watching the vent around the clock. The explosions have been at night, so it’s critical to have someone monitoring it constantly. However, monitoring an active vent isn’t as simple as sitting and staring at it.

There are several measurements geologists, seismologists, and geophysicists use to forecast eruptive activity and study an active volcano. Some of these measurable factors include earthquakes/seismicity, vent temperature, and tilt (deformation).

Seismicity and earthquakes help us see the frequency and characteristics of movement inside the earth. Some earthquakes are very shallow and originate within the volcano, oftentimes near the magma chamber. Other earthquakes are deep and come from the earth’s mantle, more than 70 kilometers (43.5 miles) below the surface. We’re concerned with the shallow ones, since they often occur in “swarms” before a volcanic eruption. Tonight I learned how to examine a seismograph and earthquake data to determine if significant eruption activity is happening.

We constantly monitor the temperature of the sulfur dioxide (SO2) gas that Halema`uma`u emits. Temperature spikes can indicate changes in vent activity, or just changes in the weather. You have to pay attention to see what is significant.

Another of the things that we monitor closely is called deformation. We use electronic tiltmeters that are semi-permanently or permanently located all around the island to measure changes in the slope of various locations. If the slope of an area increases steadily, it can indicate that the magma chamber is filling up. This can mean that an eruption is in the near future. It doesn’t always, however, so we have to make sure that we see a definite trend or we’ll be caught crying wolf. Here’s a really cool example of how volcanologists used tilt to track Kilauea’s past eruptions.

There’s more than this to monitoring, but it’s late and I have a field excursion tomorrow! It’s going to be very low-impact, since I’m still 2 days away from medical clearance to resume hardcore field work. I’m housesitting for another volcanologist now, and this one has eight cats. It’s quite a bit different than watching the two dogs at the other house! Word has gone around the office that I used to be a vet tech, so my pet-sitting skills are proving helpful to members of the staff who want their vacations.

Just so you don’t feel deprived, here’s a picture of the ocean entry plume from last week. Tomorrow will bring new and exciting pictures of Mauna Loa, Mauna Kea, Hualalai, and the Kona coast, provided the weather decides to cooperate. We’re catching the rain from a passing tropical storm, and it’s quite wet right now. Anyway, the plume awaits!