I travel out to Mauna Iki for the third time, with an established itinerary. My first task? Find a mysterious graben (block of crust that has been shifted downward relative to the blocks on either side) that we have been hearing people talk about. My partner and I teamed up with another pair to search for said graben, which was allegedly all the way at the south side of the map. We had a lot of walking ahead of us, some of it over treacherous shelly pahoehoe – but we made it to where the graben was thought to be.
Nothing.
We gave up on searching for the graben, deciding that it doesn’t exist and that people are lying. But this is a developing story. If someone can show me photographic evidence of this graben, I might reconsider.
My partner and I headed down the lava shield to trace a few lava flow contacts that we hadn’t figured out in detail yet, and cleared up some of our inconsistencies on our map before making our way back to the meet-up spot for lunch.
From that point forward, I worked on my map, writing in contact names and sketching up a legend. We must have waited there for hours before everyone else was ready to head back to camp, but return we did.
In the evening, we attended a lecture on the 2018 Kilauea Eruption, to foreshadow our work on Monday. I’ve mentioned this eruption here and there in the past, but I figured I’d write about it in a little more detail today.
It began on May 3rd, 2018 and continued through August 2018, producing about 1.4 cubic kilometers of lava. This makes it one of the biggest eruptions in the past few hundred years. Previously, another eruption had been going on in Kilauea since 1983 (35 years!) through the cinder cone Pu’u ‘O’o. Volcanologists started to notice that pressure was building beneath Pu’u ‘O’o, and the the Kilauea summit was showing signs of inflation. The lava lake within the summit then rose, overflowing.
Suddenly, on April 30th, Pu’u ‘O’o stopped erupting and completely collapsed, releasing high columns of dust and ash into the air. Then, the summit’s lava lake started to drop, followed by a series of earthquakes forming an eerie trail down the Eastern Rift Zone. The magma beneath the summit was draining and traveling down now that it wasn’t blocked by Pu’u ‘O’o.
Come May 3rd, the magma burst out of the ground in the southeast part of the island, in a residential area called Leilani Estates. Lava proceeded to cover 13.7 square miles of land, destroying hundreds of homes and displacing over 2,000 people. 875 new acres of land were added to the Big Island as lava poured into the Pacific Ocean. This resulted in steaming, explosive phreatomagmatic eruptions.
It’s difficult to imagine what that must be like… having to evacuate your home and leave behind most of your belongings, knowing that it will soon be entirely overrun by lava. Almost nothing can withstand the forces of a lava flow. So many homes, structures, beaches, pools, and resorts were lost to this disaster.
But it wasn’t over yet. The eruption down the ERZ drained out some of the magma in the chamber underlying the summit. In a series of “steps,” the summit sank bit by bit. Each collapse came with a huge plume of ash. Over 60,000 earthquakes later, the summit caldera of Kilauea had formed. It’s the same caldera I got photos of on my second day here, and the same one that is now filling with lava and lighting up the night. The crater grew from 280 ft deep to over 1,500 ft deep, putting it well below the water table. As a result, a large lake formed inside it – an unusual sight on Kilauea!
For two years, Kilauea went quiet. That is, until it erupted again in 2020! The lava made short work of the caldera lake, boiling it all off in hours. It then began to fill to its present depth.
While tomorrow is an “office day,” I will be exploring the aftermath of the 2018 eruption on Monday. Stay tuned!
I finished off my day by heading out to the caldera again, just like the past two nights. I put on some music, took some photos, and just sat out there alone on a rock by the edge of a cliff, enjoying the view. I love being out there. Once I can find an overlook to myself (away from all the others trying to see), it’s just me, the caldera, and the full moon. I could do this every night, and probably will until I leave. Each time is more magical than the last. I can’t help but be drawn to that glowing crater each moment I get. Today, when I was alone, I experienced a feeling of exhilaration I hadn’t quite encountered yet. It’s that feeling you get when you just know you won’t forget this moment for a long, long time. Maybe it was because I was by myself… I didn’t have to worry about anyone else, so I could just freely feel the eruption of all the emotions that had built up inside me.
Anika Tullos 