Helicopter fun!

1 09 2008

On Thursday I went on a geology overflight to Kupaianaha and Pu`u O`o. This area of Kilauea is in its 24th year of eruption. Pu`u O`o is a parasitic cinder cone on the flank of Kilauea, and Kupaianaha is a shield that has formed 3km down from Pu`u` O`o.

The first part of the flight consisted of travelling down the path of the flows towards the current ocean entry.

This is a view to the northeast. The older flows are darker, and the younger flows are silvery.

This is the ocean entry plume shot from above. The lava is pouring into the ocean from a lava tube that is just under the hardened surface flows. The plume is poisonous sulfur dioxide gas (SO2).

Here’s a shot of the plume as we were flying away. Helicopters can induce some funky camera angles.

The helicopter dropped us off further up the flow field so that we could take some measurements. Two of my colleagues are performing Total station measurements with Pu`u O`o in the background. These measurements help us to determine how the ground around the active lava flows and lava tubes is deforming. We can measure elevation change and distances, among other things.

After we finished with the Total station, we hiked towards Pu`u O`o to map a new seep of “toothpaste” lava. This texture of lava is considered to be a transitional stage between smooth pahoehoe and rough a`a flows. We use GPS tracklogging and walk along the boundary of the seep to create the map. That’s what I’m doing here.

The lava seep is from just a few months ago, so the lava itself has an interesting array of colors and textures. There are many small vents of hot SO2 that waft up from beneath where we were standing. I was examining some of the textures and enjoying the warmth of my own volcanic sauna.

After we mapped the boundaries of the seep, we measured the thickness of the seep itself. I was holding the base of the tape measure and recording the data.

The helicopter met us after a few hours and flew us over Pu`u O`o for a look at the current eruption. For those of you waiting anxiously for the smoking cone, here you go!

Of course, this doesn’t provide a good perspective of how large Pu`u O`o really is. That’s why I’m including this image as well.

Those very small, silver dots near the rim in the foreground? Those are our measurement stations. They’re about the size of an average adult. Yes, Pu`u O`o is large. Flying over it was incredible.

I hope everyone is having a wonderfully restful long weekend!

It’s work time…field work, that is.

26 08 2008

It’s high time that I posted about the field work I’ve been doing lately. Before I became sick last week, I was out mapping the newest lava flows at Waikupanaha. Well, it was a gorgeous day and I did manage to snap a few pictures before the hospital called.

While hiking to where we were to begin our mapping, we heard and saw some lava bubble bursts to the left of the ocean entry plume. Unfortunately, a watched pot never boils and neither does a watched ocean entry. As soon as I pulled my camera out, the bursts stopped. Ah well, at least the ocean entry plume still looked good.

This is a view to the south, and you can see the pali (or cliff) at the right of the frame. The lava flows toward the ocean from very far up the pali, sometimes aboveground and mostly underground through lava tubes.

The way we map new lava breakouts is by putting handheld GPS units on Tracking mode and then walking along the boundaries of the fresh lava. It’s a good way to map, since you can set the GPS to record your position at intervals of three seconds. The level of accuracy is enough for our purposes. After all, the flow field changes fairly often.

Moving on to the field work I did on Friday (it wasn’t too strenuous, don’t worry)! We met up with a cultural resources guy from Pohakuloa Training Area, a massive area between Mauna Loa and Mauna Kea where the Army and Marines practice bombing and combat. The samples we needed to obtain were on the military’s land, so we have to go through the proper channels to collect them.

There’s a bit of archaeology in what we were doing there.

That is a pit dug by the ancient Hawaiians. No one is sure why they dug these pits, which happen to be about 9,000 feet up the slope of Mauna Loa. We collected samples of the displaced rocks to perform the same Chlorine-36 cosmogenic isotope dating that we did on Mauna Loa’s summit. The reddish lava flow that the pits are situated in is of unknown age, so we’re also going to date that as well. It should give us an idea of how long ago the Hawaiians made the pits.

I suppose it can’t hurt to throw in a picture of the other massive volcano on this island. If you can make out a small whitish blob in the left foreground, past the plants…that’s our truck. This might give some sense of how gentle this particular slope of Mauna Loa is. Trust me, they’re not all like that!

Tonight is my last night housesitting, so my internet access (and consequently posting) should pick up a bit this week.

Office work for the glory of science!

22 07 2008

Having an injury while in Hawai`i for a summer of outdoor research is definitely a drag. Even my meager plans to go snorkeling last weekend were derailed by rainstorms. My boss wouldn’t let me go to the ocean entry tonight because I’m not medically cleared until this Friday. ((Sigh))

To say that desk work is frustrating doesn’t begin to convey today’s small agonies. I’m attempting to georeference new and improved satellite photography for our mapping project. I am using a program called ArcGIS, and its offshoot known as ArcMap, to compare the old satellite imagery with the new. Unfortunately, the new images come to me as 1 kilometer squares with absolutely no reference points (aside from their topographic features). I have to place the new image over several older ones and then compare distinctive features to link the images up. Imagine trying to take two different tracings and line them up as closely as possible by stitching them together. It’s a very time-intensive job, since you have to look for the smallest recognizable features to stitch in order to make an accurate map.

I spent 5 hours working on one quadrant (Mauna Loa’s summit and the NOAA Weather Observatory on its flank). Guess what happened? Yes, the computer lost the data. 26 meticulously georeferenced points. 5 hours of beating the thing into submission, and all for naught. ARGH. I will conquer it tomorrow, I swear.

Here’s a sample of the type of images I’m working with. The Big Island is 10,432 square kilometers. Each image I work with is one kilometer. You can see how this would take quite a while.

Since I haven’t posted one of these before, this shows how much of the Big Island’s surface area is covered by its various volcanoes. Mauna Loa is huge, and covers 51% of the island. Remember that Hualalai, Mauna Loa, and Kilauea are the only 3 active volcanoes. Hualalai has been dormant for some time, and doesn’t have much eruptive capability left. Kilauea is always erupting (these days) and is the current star of the show. However, the amount of lava produced by Kilauea in one day was produced by Mauna Loa in 20 minutes in 1984. It’s far and away the most potentially dangerous volcano in Hawai`i.

Thankfully, we’re going on a field trip up Mauna Loa on Thursday. I am so excited to get out of the office it’s almost silly. The week after this one I’ll either be hacking through the low jungles of Mauna Loa’s eastern flank doing a gravity survey, or up on Mauna Loa’s summit doing more kinematic GPS. Down with office work!*

*Bear in mind that office work is also necessary for good science, and that the author of this post is just mildly stir-crazy.