Nouvelles du volcan Kilauea
Kilauea volcano update: Kilauea's lower East Rift Zone eruption continuous with vigorous fountaining from fissure 8 and lava flowing into the ocean at former Kapoho Bay
mardi juin 12, 2018 15:41 | IS
The three closely spaced lava fountains at fissure 8 are building a cinder-and-spatter cone around the erupting vent through downwind accumulation of lava fragments falling from the fountains. (HVO/USGS)
Aerial photograph of some minor overflows of the upper fissure 8 lava that sent small flows of lava down the levee walls. These overflows did not extend far from the channel and hence did not pose and immediate threat to nearby areas. Channel overflows like the ones shown here add layers of lava to the channel levees, increasing their height and thickness. (HVO/USGS)
Lava flow and fissure map as of 3:00 p.m. HST, June 11, 2018. Besides the ongoing lava fountaining from fissure 8, only fissures 16 and 18 are active with some mild lava spattering. Most of the large lava flow formed and sustained by fissure 8 is now flowing into the ocean, covering only small additional areas of land along its sides. Shaded purple areas indicate lava flows erupted in 1840, 1955, 1960, and 2014-2015. (HVO/USGS)
Kilauea’s eruption in the lower East Rift Zone continues without showing any signs of weakening. The current activity has been sustained for 38 days now, 2 days longer than the last fissure eruption that occurred in this area in 1960. However, compared to the rapid change of activity locations and advancing lava flow fronts, the eruption seems to have geographically settled for the past week.
This thermal map shows the fissure system and lava flows as of 6:45 am on Sunday, June 10. The flow from Fissure 8 remains very active, its lava entering the ocean at a single entry point in Kapoho. The black and white area is the extent of the thermal map. Temperature in the thermal image is displayed as gray-scale values, with the brightest pixels indicating the hottest areas. (HVO/USGS)
Fissure 8 remains the centre of activity with a line of closely spaced vents that continue to erupt lava. The height of the produced lava fountains thereby fluctuates between 35 – 55 meter (115 - 180 feet), just above or below the rim of the large spatter cone (pu’u) that they build up along the downwind side of the vents. Lava fountaining from fissure 8 continues to feed a fast-moving channelized lava flow trending north and then east to the ocean entry at Kapoho Bay. Hawai’i Volcano Observatory scientists estimate the lava output to reach up to approximately 100 cubic meters per second!
The width of the active part of this long lava channel varies along its length, ranging from about 90 to 275 meter (100 to 300 yards) wide, splitting from 1 channel into a braided lava river that comes back together before turning eastward to Kapoho. Despite the fact that this channel is full of lava, only minor overflows of the channel levees occurred along the length of the lava flow which so far were short-lived and hence did not pose an immediate threat to areas not previously covered by lava.
Comparison of previous lava flow maps and thermal maps with the current ones show that the wide lava channel flowing over what used to be Kapoho concentrates into a narrow funnel from where there is now only 1 main ocean entry. The lava that has filled Kapoho Bay in the past week built a new lava delta which is now about 1 square kilometre (250 acres) in size.
The interaction of molten lava flowing into cool seawater causes pulsating "littoral explosions" that throw spatter (fragments of molten lava) and pieces of solidified glassy lava high into the air. HVO/USGS warns that these ocean entry littoral explosions can create hazardous conditions both on land and at sea, because the lava fragments can be thrown far inland, as well as seaward. Volcanic gas emissions from the fissure eruption remain very high, a recent measure indicated them to be nearly twice the value of the past two weeks.
The only other activity in the Lower East Rift Zone fissure system was glow, degassing and weak spattering noted for the last several days at Fissures 16 & 18. This activity is however not creating any lava flows.
You can find some spectacular and fascinating images of the fissure 8 fountaining, lava flow and ocean entry on the Facebook page of Bruce Omori (Extreme Exposure Fine Art Gallery) who undertakes almost every day an early morning overflight with Paradise helicopters:
Bruce Omori (Extreme Exposure Fine Art Gallery) photographs of 11 June 5h45 am overflight:
Bruce Omori (Extreme Exposure Fine Art Gallery) photographs of 10 June 5h45 am overflight:
Meanwhile at Kilauea’s summit the caldera continues to subside, resulting in inward slumping of the rim and walls of Halema`uma`u crater along with a ca. 24h returning pattern of increasing seismicity that builts up towards a small explosion with abve M5.0 earthquake after which there is a short break before seismicity picks up again. Sulfur dioxide emissions from the volcano's summit have dropped to levels that are about half those measured prior to the onset of the current episode of eruptive activity.
mardi, juin 12, 2018
lundi, juin 11, 2018
dimanche, juin 10, 2018
samedi, juin 09, 2018
Kilauea volcano update: Kilauea lower East Zone Rift eruption: continued vigorous lava fountaining from fissure 8
samedi, juin 09, 2018
The eruption in the lower East Rift Zone remained concentrated on fissure 8, where continuous vigorous lava fountaining fluctuates, at times reaching heights of 70 meters (230 feet). This activity continues to feed the lava channel flowing northeast before turning westward toward Kapoho where it transforms in a very broad lava flow that by now almost entirely covered Kapoho and Vacationland and filled up Kapoho Bay. Sideways moving of this broad Kapoho Bay lava flow creeps north through what remains of Kapoho Beach Lots, but none of the other previously active lobes of the large fissure 8 flows are receiving fresh lava and have hence stalled. Also no other fissures apart from fissure 8 were actively erupting lava in the past few days. The only activity observed was some incandescence from fissure 24 and heavy fuming from fissures 24, 9 and 10 – all located just west of fissure 8. ... [details]