Sunday, December 20, 2020

Kilauea Roars Back to Life!

****BREAKING****

**UPDATE 12/28/2020**

There has been no significant change lately, except that weak summit inflation briefly dipped to deflation, and then back to inflation again. Down rift in the LERZ, the magma supply appears to be favoring the summit eruption, and gradual inflation is now trending towards deflation. 

The lava lake level has remained steady, and the 'island' of cooled rock that has been floating on the lava lake continues to circulate and shrink over time. 

The last active vent has 2-3 small steams of lava pouring out, and SO2 output has decreased significantly within the last day. 

All updates can be found here at Hawaiian Volcano Observatory (usgs.gov)

**UPDATE 12/26/2020**

The lava lake rose to the level of the North fissure, and appears to have stopped it. Lava appears now to be draining back into the fissure, as a 'crust ledge' has formed around the lava lake, and the molten lava is lower than the ledge. The East fissure is slowly spattering lava out back into the lake. It is entirely possible given these developments that the eruption ceases within the next several days or weeks, as the lava lake cools, and the pressure in the shallow magma chamber decreases.


Thermal Time-lapse from HVO on 12/26/2020 shows the inundation and 'death' of the North fissure, while activity from the East (lower fissure resumes).

Summit inflation has also slightly resumed, which could be due to the North fissure now being 'plugged' or receiving lava back into it. 


Summit changing from deflation to inflation, a DI event.

What this means for now is not certain, as this could be a minor inflation, deflation event, or could signal a positive pressure change. The next few days should be telling.

Down rift at Puʻu ʻŌʻō, a slight deflationary trend has been noted, likely due to lack of fresh magma supply as it erupts from the summit. 


**UPDATE 12/22/2020**


The lava lake continues to rise, and it's surface is just beginning to overtake the North fissure's edifice. Hawaii health officials have begun resuming 'vog' (volcanic fog) warnings to residents.

By tomorrow, a new dynamic in the lake should unfold as the magma source becomes lower than the lava lake surface. Spatter cones may form, the lava lake may continue to rise, or it may stop and simply circulate. There is no way of knowing at this point. Summit deflation is consistent with magma release, with the latest subsidence readings at about 0.10 meters in the last several days.

Deflationary event post-fissure eruption and lava lake formation. Copyright HVO.


Down rift to the Lower East Rift Zone (LERZ), the inflationary trend near the 1983-2018 Puʻu ʻŌʻō vent continues a steady upward inflationary trend, apparently unaffected by the summit action at Halema'uma'u caldera. Time will tell if eruptive activity resumes at both vents, although at this point, HVO does not seem overly concerned with this.

Current inflationary trend at Puʻu ʻŌʻō. Copyright HVO.


HVO had been weighing raising the alert level at Kilauea in recent days/weeks, and purportedly were about to do so the night of the eruption, when the eruption occurred suddenly. 

Neighboring Mauna Loa was raised to Yellow alert after the cessation of Kilauea's long-lived eruption which began in 1983 and ended in late 2018. 

Lava lake surface approaching main fissure vent during 12/21-12/22, 2020.

The next few days should give an indication as to whther this lava lake and eruption will be sustained, or short lived. A minor magma intrusion did occur earlier this month at shallow depth, and on occasion, these do result in minor effusive eruptions. 

More updates will follow. 

**UPDATE 9:06pm HST 12/21/2020**

The latest image shows that the lava lake has risen even further. The rate of rise has slowed either due to less lava output, or due to the diameter of the crater widening as levels rise. It appears at least one fissure is issuing lava from beneath the lava pool surface, while two fissures on the crater rim are continuing to issue lava as well. Earlier reports indicated one fissure had ceased, but it is difficult to tell from the images whether this is still the case.

It is still unknown how long the eruption will continue for, and whether other phases will occur.

At this time there is minimal danger to the public as, according to HVO, "The eruption has stabilized" and ash emissions have ceased. HVO lowered the aviation color code from RED to ORANGE in response, after the former water lake had been completely evaporated and lava/water interactions ceased. 





**UPDATE 12:05PM HST 12/21/2020**

Animated GIF From HVO shows the rapid rise of the lava in the crater.




**UPDATE 11:00am HST 12/21/2020**

The caldera floor has now been filled up to the N eruptive fissure, according to the latest Summit Webcam shot (the quality is low, and the HVO web server appears to be under some stress at the moment).

It appears the SW fissure may now be underneath the lava lake, and that the lava lake is now nearly up to the point of overtaking the largest fissure at the N wall of the caldera. The lava lake has greatly exceeded the level of the former water lake.

Image from approximately 8am HST


It is not known how long the eruption will continue.


 Image from about 11am HST

As you can see above, the lava lake is rapidly rising. If the eruption continues throughout the day, there is the possibility that it will overtop the new collapse crater and fill the caldera in further.

   

**UPDATE 8:00am HST 12/21/2020**

According to USGS, the eruption currently consists of three crater wall fissure vents, and the lake is completely gone. A lava lake is forming within Halema'uma'u crater. The eruption so far is limited to the summit, although it is unclear whether any activity may start down rift. 

The eruption in 2018 was spurred by rapid summit lava drainage down rift to Pu'u'O'O crater, which then drained further down the LERZ to the Leilani Estates area. Given that magma still exists down rift from that eruption, and that it is still reasonably hot, it is always possible that the 2018 system can receive a new injection of magma. 

It is too soon to tell what the return of a summit lava lake will mean, or if this eruption will be long lived, or a shorter episode resulting from the minor magma dike intrusion a couple weeks ago. The eruption could go for only days, or go for on for weeks to years. The previous eruptive period on Kilauea was from 1983-2018, with lava present first at  Pu'u'O'O, and then simultaneously with Halema'uma'u, ultimately resulting in the LERZ fissure eruption.





**UPDATE 11:57pm HST 12/20/2020****

Local News now reporting Hawaii Island erupting again, new eruption in Halema'uma'u (khon2.com)

A 4.4 Mag temblor was recorded downrift on the LERZ preceding the summit eruption. It is unclear how this is related at this time.


***UPDATE 11:09pm HST 12/20/2020****

HVO Has now raised the alert level to RED for Kilauea. Kīlauea - Volcano Updates (usgs.gov)

Shortly after approximately 9:30 p.m. HST, the USGS Hawaiian Volcano Observatory (HVO) detected glow within Halemaʻumaʻu crater at the summit of Kīlauea Volcano. An eruption has commenced within Kīlauea’s summit caldera. The situation is rapidly evolving and HVO will issue another statement when more information is available.

Accordingly, HVO has elevated Kīlauea’s volcano alert level to WARNING and its aviation color code to RED.

Alert levels and aviation color codes are explained here: https://www.usgs.gov/natural-hazards/volcano-hazards/about-alert-levels

HVO continues to monitor the volcano closely and will report any significant changes.

Stay informed about Kīlauea by following volcano updates and tracking current monitoring data on the HVO web page (https://www.usgs.gov/volcanoes/kilauea/volcano-updates) or by signing up to receive updates by email at this site: https://volcanoes.usgs.gov/vns2/.

HVO is in communication with Hawai‘i Volcanoes National Park as this situation, which is taking place within the park, evolves.

HVO is in contact with the County of Hawai‘i Civil Defense Agency.

Recent Observations:

For the past several weeks, the USGS Hawaiian Volcano Observatory (HVO) has recorded ground deformation and earthquake rates at Kīlauea Volcano’s summit and upper East Rift Zone that have exceeded background levels observed since the conclusion of the 2018 lower East Rift Zone eruption and summit collapse.

Beginning in September 2020, increased rates of uplift were observed by GPS stations in Kīlauea’s upper East Rift Zone. In the past month, increased uplift has also been measured at GPS stations in Kīlauea’s summit region. While uplift related to post-collapse inflation of the summit reservoir has been occurring since March of 2019, rates have been steadily increasing in recent months and are currently higher than they have been since the end of the 2018 eruption.

In late November 2020, increased earthquake rates began when seismic stations recorded an average of at least 480 shallow, small-magnitude earthquakes (97% of which were less than or equal to magnitude-2) per week occurring at depths of less than 4 km (2.5 miles) beneath Kīlauea's summit and upper East Rift Zone. This compares to a rate of fewer than 180 per week following the end of Kīlauea’s 2018 eruption and through early November 2020.

On December 2, 2020, GPS stations and tiltmeters recorded a ground deformation event at Kīlauea’s summit. Accompanied by earthquake swarms, the patterns of ground deformation observed were consistent with a small dike intrusion of magma under the southern part of Kīlauea caldera. The injection resulted in about 8 cm (3 inches) of uplift of the caldera floor, and modeling suggests that it represented 0.4–0.7 million cubic meters (yards) of magma accumulated approximately 1.5 km (1 mile) beneath the surface. Though the intrusion did not reach the surface and erupt, it represented a notable excursion from trends observed in Kīlauea summit monitoring data streams following the end of the 2018 eruption.

On December 17, 2020, seismometers detected a notable increase in occurrence and duration of long-period seismic signals beneath Kīlauea’s summit, which are attributed to magmatic activity. Whereas this type of seismicity was observed on average once every few weeks following the 2018 eruption, rates have increased to over a dozen in the past several days.

Other monitoring data streams including volcanic gas and webcam imagery were stable until this eruption.

An earthquake swarm began on the evening of December 20, accompanied by ground deformation detected by tiltmeters. An orange glow was subsequently observed on IR monitoring cameras and visually beginning approximately 21:36 HST.

***Original post below***

10 minutes ago HST, Kilauea has now roared back to life, according to HVO.


This marks the first resumption of eruptions from Kilauea since the cessation of eruptive activity after the 2018 Leilani Estates/LERZ eruption, which destroyed over 700 homes and displaced twice as many people. 

It is unknown what role the water lake has had in the eruption at this time, however according to the above image, it appears to have been vaporized. There appears to be no trace of it in new images, and due to the time of night, is it unclear if a phreatic eruption has occurred, which was hypothesized. 


Current screen grab from HVO's Kilauea Summit Cam



More news will follow.

Right now, you can follow the Facebook page of Hawaii Volcanoes National Park for updates.

Kilauea was previously at Green alert, after a little over two years of quiescence. Following the 2018 eruptive episode, long periods of inflation were recorded, including a recent dike intrusion event. These events were apparently not enough for HVO to become concerned that a new eruption may take place, even though the intrusion was quite shallow, as had been many recent quakes.

Hawaii Island has been hit both by the COVID-19 pandemic, as well as the recent eruption of Kilauea in its Lower East Rift Zone, which erupted in the middle of a neighborhood development, and near a geothermal power planet, the Puna Geothermal Plant. This plant only recently reopened for power generation, and it is unclear whether or not renewed activity at Halema'uma'u will change this.

I expect that the aviation color code will be raised to orange/red, and that the local code be changed accordingly as well in the next USHS HVO Update. 

This is a developing situation, and more updates will be posted as the eruption progresses.

Mauna Loa is also on Yellow alert at this time. A recent deflation event at the summit may or may not have contributed to pressurization of Kilauea, but it is possible. Mauna Loa had been consistently inflating until just a few days ago when a dike intrusion was detected at Kilauea Summit. Whether this is a true correlation is a mystery at this time. 

Residents near the volcano should heed the warnings of local authorities, and evacuate immediately if necessary. Kilauea's behavior of late is not exactly predictable, and quakes have been detected down-rift of last as well. A 2.8 quake, and many smaller magnitude, but still over 2.0 quakes had been detected today down to Mauna Ulu, the site of the eruption preceding that of Pu'u'O'O in 1983.

This is a rapidly developing situation, and many new updates will be posted. 

Hawaiian local news is not yet reporting on the eruption. 






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