The erupting fissure stretched for nearly a mile across the down dropped block. This block is an enourmous slab of the old caldera floor, a mile across and wide, it had slumped down hundreds of feet during the 2018 Kilauea caldera collapse.
USGS reports had dubbed this slab the “down-dropped block” where it is routinely referred to in the daily reports of eruptive activity. The lower western edge had succumbed to the lava lake slowly filling the lower sections of the collapse pit where the edge of the block had become flooded by the growing lava lake.
This block had slumped down nearly intact, the top still flat, if now somewhat tilted to the west. The old features atop this block still visible including pahoehoe flows, old eruptive vents, and the hiking trail I had once hiked in crossing the caldera floor.
The old Halemaʻumaʻu Trail could still be seen as a lighter path beaten across the black lava by thousands of hiking boots. The trailhead was at the Halemaʻumaʻu parking lot, the pavement of that lot and sections of Crater Rim Drive still visible on smaller slump blocks on the west side of the caldera, also hundreds of feet below the original caldera floor.
The September 2023 eruption started as a fissure right across the down dropped block. For almost a mile fountains of lava surged and frothed. The down dropped block completely bisected by the eruption.
One small vent marked the end of the fissure, right at the eastern end where lava had forced its way through the pile of debris at the cliff that marked the block’s edge. Overlooked by most with far more spectacular fountains to be enjoyed. I found that last little vent fascinating where lava tumbled down through the talus.
I have not had a chance to look again, but I suspect this eruption finally covered over much of that section of the hiking trail. I wonder, one day when the caldera floor is filled by this series of eruptions if there will once again be trails out to cross the caldera, and if I will still be around to hike them.
Yes, she is rumbling again, mere weeks after the last eruption ended.
Inflation at the summit has surged with a vengence, the pressure under the caldera right back to where it was at the start of the September eruption. A persistent pattern of earthquakes rumbles beneath the southwestern flank indicating intruding magma.
The USGS has noticed, they are back to issuing daily reports. The park service has noticed, trails in the southwestern rift zone have been closed. Local photographers have noticed, plans are ready to spring into action with grab-and-go bags of photo gear by the door.
The Kilauea eruption that started one week ago today is pau. To translate that from Hawaiian to English… Done.
The eruption had notably waned over the last couple days, comments on social media and webcam video indicating sluggish spatter within the small cones that had built up over the last week around the fissures. Last night numerous small bits of glow were visible all across the crater floor, but no fountaining was in evidence.
Today’s USGS Volcano Observatory report is clear… “The Kīlauea summit eruption that began on September 10th stopped yesterday, September 16th, and is unlikely to restart.”
So we wait for the next one, any bets?
My Facebook post describing a last moment mission to the volcano caught the attention of one of our local reporters. Result? An interview and a little piece about volcano viewing carried on several of the local media outlets. Nothing serious, they are just trying to capture the event of the moment and the local response. Perhaps something positive in the face of all the tragic fallout from the Lahaina disaster that fills the local news. Not my first time in the news, but the first time in a while, it is always fun…
Watching the recent and repeated eruptions in the Kilauea caldera has made an interesting bit of info clear… The first few hours are the most spectacular.
Months of inflation Kilauea had stored large quanities of gas and built up a considerable amount of pressure, enough pressure to lift the megatons of rock above the magma chamber and cause the entire summit region to swell outwards.
Beween eruptions USGS geologists and armchair vulcanologists like myself keep an eye on the tiltmeters as the pressure in the volcano builds, awaiting the time that accumulating magma and increased pressure bursts through the overlying rock to begin a new eruptive cycle.
At 15:13 HST Sunday afternoon that moment came.Continue reading “The First Few Hours”
The question of the week… Is it over?
Eruptive activity began to wane at the end of last week,with the lava fountains diminishing, then disappearing over the weekend. Views in the webcams showed a steady decrease in activity at fissure 3 over the course of several days.
At this point no lava appears to be emerging onto the surface, with only a few dribbles left in the lava flow to be seen as minor glows across the flank of the mauna.
Oddly Kilauea, after erupting continuously for over a year seems also to have paused. There is no longer any visible lava or even a glow within the Halemauʻmauʻu crater.Continue reading “Is it over already?”
On the way home in the eve the red glow dominates the horizon. Going to work the next morning it is the plume on the skyline. The eruption is ever present.
When moving to the island fifteen years ago I had looked at the mauna and thought to myself… One day you will erupt, will it be during my time on the island? This though has occured to me many times in the intervening years… When hiking the lava flows in the saddle, when driving up and down Mauna Kea to work looking across at the many flows streaking the flanks of Mauna Loa. How many times have I looked up and wondered when? One day.
That day was Sunday, November 27th, 2022.Continue reading “Mauna Loa Awakens”
I am not certain what woke me up at one AM, but I was awake. Before going back to sleep I decided to check the satellite photos to see if I might get some telescope time before dawn. But what I found online had me totally awake and grabbing a couple batteries for the camera.
Mauna Loa has awoken.
I was soon driving out from the house to a point above the village with a clear view of the mauna. The whole southern sky an angry red over the village as I drove. I did not have to drive far, just a couple minutes from the house where you can find a clear view. Pulling off I set up the camera and shot.
I was not the only one out, half a dozen cars could be seen stopped along Waikoloa Road to view the eruption. The whole mauna is lit up red and it looks like the west flank is erupting, not just the caldera as Civil Defense currently insists. Just the clouds lit up on that side?
Life is intertesting.
Update: By dawn much of the caldera has flooded with lava. Scale is hard to see in the photos, you have to recall that the caldera is almost two miles across and three miles from end to end.
Update 9:11am: The eruption has already migrated to a series of fissures on the northeast flank. The typical Mauna Loa eruption script is a summit caldera eruption followed by a flank eruption a few days, or a few weeks later. We have just seen that happen in a few hours.
I am including a couple photos here taken by a co-worker as she commuted across the saddle this morning at dawn. You can already see the lava flows making their way into the saddle…
Earthquake activity is on a bit of an uptick around here. While the mag 3.9 that woke us up a few nights ago was probably just a settling event under Mauna Kea, much of the remaining activity is under Mauna Loa. This includes a 3.7 magnitude event last night, part of an ongoing swarm under the long mountian.
Mauna Loa’s activity has remained elevated for some weeks now. There are two swarm centers. One directly under the caldera, but more interestingly a persistent swarm under the northwest flank a few kilometers away.
All of this has the island buzzing with concern. On social media, in the local papers, Mauna Loa is the subject of much speculation. The official line is that no eruption is imminent, but officials are quick to remind residents to monitor local emergency channels and have an evaculation plan at the ready.Continue reading “This is a Bit Concerning”