My coworker Ethan loaned me his Roadside Geology of Hawaii book, so I had made plans of all the cool geologic places to visit. Several of these were around Hilo, so we decided to spend a few nights there instead of wasting time driving every day. We ended up staying in three different spots on the island. I think some friends thought we were crazy, but I am used to moving around on field trips, why not do the same for vacation?
First stop of the day were the Boiling Pots! These stepped ponds at the base of a waterfalls were cool by themselves, but there were even more cool geologic things once you hiked down there. I took a few photos at the overlook, then we hunted around for the trail down.
Except the trail down did not exist. Everything was blocked off with big “Danger” and “Do Not Pass” signs. I kept thinking the trail was hiding somewhere, but every option had a sign and barricade in front of it. I finally came to the sad realization that there was not going to be a hike down to the boiling pots. :(
We headed over to Rainbow Falls instead, which was just downstream. There were supposed to be trails there as well. Guess what? All blocked off again! I was starting to feel like Hawaii didn’t want us to have any fun! Ok, in full disclosure, I googled it. The trails around Boiling Pots were blocked off after several people drowned - apparently those currents were pretty stout and the trails were not very good.
Fine, Hawaii. You win.
Our hotel was on Banyan drive and was covered in Banyan trees. They were also all around the falls. There was enough of them to form a shaded canopy and it was super cool and so alien looking. If it had been lunch time, it would have been a perfect picnic location. Next time!
My last spot to try from the guidebook was Kaumana Caves - which is a lava tube that had a skylight (roof) collapse shortly after formation and was big enough to walk through and explore. When we first arrived it looked like the caves were blocked off and I was about to lose it!
Luckily, that wasn’t the case, it was just a bunch of warnings and guardrails. :) We got down the staircase and realized it was super duper dark in the caves. Luckily, I had thought to pack a head lamp, so I ran back to the car to get it. Unfortunately, the batteries were low and the light didn’t really illuminate anything!
iPhones to the rescue! We used the flashlight function on the phones to work our way into the cave. We didn’t get too far back before even they weren’t super helpful. Who knew a lava tube could be so pitch black? I noticed that the walls had a cool yellow or white sheen when the light hit them, so I took a photo. I still have no idea what it is - maybe some kind of lichen? I was trying to get a good view of the lavacicles hanging down from the roof, but most of the ones I found were pretty small. So just pretend with me that they are more awesome than they look! ;)
We headed back to the entrance once it looked like we might have to start crouching down or crawling to get through. We are not quite that adventurous!
We then headed to Volcanoes National Park. There are plenty of trails and things to see, but I wanted to go walk on the lava that had taken out the Chain of Craters road back in 1983. It looked like just a short hike from the end of the road, so we headed down to the edge of the park.
To be met by this! What?!? Not another blocked off area!! I was muttering under my breath about just wanting to live my life and walk on some lava that had gone over the road. As much as we had picked the island for active volcanoes, there haven’t been any flows this year, so it was pretty darn safe to be walking around. Sigh…
I had to settle for walking around on the lava cliffs on the appropriate side of the fence. The views were gorgeous, the water was beautiful and while it was overcast toward the volcano summit, it wasn’t raining at the coast.
Plus there were these super green plants dotted along the black lava rocks, so they looked especially vibrant. The terrain in the part was actually super varied. When we were driving down the Chain of Craters road, it was almost jungle-like vegetation. We were so confused as to where the lava was. Then there would be a break in the trees and a vast expanse of black jumbled rock. It was the neatest thing. They had the different flows dated so you could see how much vegetation had grown in the last 30 years or so.
This park is almost entirely the volcano Kilauea, which butts up to the largest volcano, Mauna Loa. Kilauea is smaller, but is the most active of the volcanoes at the moment. But recent is relative, most of the lavas are pretty old. The maps show which ones that have been recorded and those range from the 1800’s to today. The most recent flows are in the East Rift Zone of Kilauea starting in 1983 and going until today. This picture is of a fault scarp (pali) of Kilauea that shows the more recent flows in gray and black, with the untouched ground (kipuka) in between. You can tell the relative age of the flows - the darker it is, the more recent it is.
Driving back up the Chain of Craters road, I suddenly noticed an old road below us that was covered in lava! After making Matt stop the car, I finally got to tromp around on lava rock covering the road. I don’t know when this particular one happened, likely sometime in the 80’s, but they left the old road as it was and built a new one higher up the hill.
I wonder how much lava has to cover a road before it is easier to make a new one than the repair the old one?
We figured this would be a great photo opportunity to use my new fancy tripod and get both of us in the photo. Matt sat down and I went to set up the tripod - only to realize that the connector piece for the camera was missing. We carried it all the way there and won’t even get to use it. Sigh… It would have been a good photo, poor Matt looks so lonely by himself. :(
I don’t remember all of the volcanic geology from my undergraduate days, but I did remember that there are two types of lava, which have retained their Hawaiian names. ‘A’a is the rough and chunky kind and Pahoehoe is smooth and ropy. The chemical composition is the same, but Pahoehoe is much more fluid and smooth, while ‘A’a is jagged and chunky. They are pretty easy to tell apart, even from a distance.
The Pahoehoe was my favorite. Not only is it much easier to walk on, it had the neatest flow patterns preserved. It looks like the same patterns I see while pour cake batter, so that gives you an idea of how fluid it is. Plus the fact that those patterns are preserved gives you an idea of how fast the surface cools!
On a related note, the cooling effect is how the lava tubes form. “Channels” of lava tend to cool on the outer edges first while the inside of the channel remains hot enough to continue flowing. Once the supply cuts off, the remaining lava drains out of the channel and leaves behind a tube of lava rock - which ca be quite large. The Thurston Lava Tube is in the park and you can walk through the length of it, plus it is quite well lit!
But it wouldn’t be Hawaii without one more Danger sign! The roof of the tubes aren’t an even thickness and some are covered by future flows, but luckily some collapsing is good as it allows access to the tubes. Other collapsing, like the kind behind this sign, is best to be avoided. :)
The park is also littered with craters (thus the Chain of Craters road), these range in size from fairly small all the way up to the massive craters at the summit that are called Calderas. These form when the magma chambers beneath drain away and the volcanic summit collapses. The summit caldera for Kilauea has an active magma lake just below the surface - it isn’t visible from the ground, but the glow from the super hot magma can be seen at night. So we headed that way before the sun went down.
We stopped at the steam vents on the way to the caldera overlook. There is steam coming out of the ground all over the place in this park, but this particular pull off had an abundance. There were two right at the parking lot that had guardrails around them, so you can safely stand next to them. But don’t be fooled, that steam is still pretty darn hot (and stinky)! And the threatening rain finally made a pretty awesome double rainbow right at the overlook, we were all pretty excited and taking photos. When the light was just right it was reflecting up to four times - which of course was impossible to get in a photo!
Finally we made it to the caldera! The caldera was pumping out steam and smoke, but no glow is visible during the day. But the caldera in front of the sunset was quite a sight by itself.
As an aside, Matt and I aren’t usually too into selfies, but this trip we took a ton of them and sent them to my mom to show the boys. The first few ones we sent got such a happy response that we just kept sending more and more. A good majority of these had silly faces because they made Thomas laugh. In related news, apparently everyone else in the world has already jumped on the selfie band-wagon, I think I saw about 50 different people using self sticks!
We retreated into the Jagger Museum to wait for the sun to go down since it was raining pretty good. It was pretty interesting to see the old photos and how close people used to get to actively exploded volcanoes - with the caption of “we now know how unsafe this is”. After reading all the displays, we decided to head back outside. The glow was pretty awesome!
It just seemed to get brighter and brighter, the darker it got outside. It’s so hard to imagine just how hot it must be in the bottom of a caldera that doesn’t seem that far away. It was well worth the wait and the rain to see. It may not have been an active flow threatening to envelop our jeep, but it was a neat sight to see! And a lot safer too! :)