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Thread: Kīlauea Activity

  1. #61
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    Quote Originally Posted by Trebuchet View Post
    It was the early '80's when we were there, so yeah. My recollection is that the car rental companies forbid taking them up there.
    Ours was a standard 2 wheel drive rental vehicle hired from Hilo airport. The road was in excellent condition .. fully sealed (etc).
    There doesn't seem to have been any volcanic intrusions or quakes along that route since then (its all seems pretty stable in that direction).

  2. #62
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    From Wikipedia:
    Route 200, known locally as Saddle Road, traverses the width of the Island of Hawaiʻi, from downtown Hilo to its junction with Hawaii Route 190 near Waimea. The road was considered one of the most dangerous paved roads in the state, with many one-lane bridges and areas of marginally maintained pavement. Most of the road has now been repaved, and major parts have new re-alignments to modern standards. The highway reaches a maximum elevation of 6,632 feet (2,021 m) and is subject to fog and low visibility. Many rental car companies used to prohibit use of their cars on Saddle Road, but now allow use of the road. The highway experiences heavy use as it provides the shortest driving route from Hilo to Kailua-Kona and access to the slopes of Mauna Loa and the Mauna Kea Observatories.
    Apologies for the digression. There's also a road around the coast to the northwest, it appears.

    Back on topic, the Hale Ma'uMa'u crater has undergone dramatic changes in the past few days, with the walls caving in.
    Cum catapultae proscriptae erunt tum soli proscript catapultas habebunt.

  3. #63
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    There's some really neat images and relatively recent info on the caldera changes here.
    There's also a hi-def video of summit fly-overs conducted from June 5th showing what's been going on (takes forever to load, however).

    PS: Probably not: but there looks to be a set of footprints leading right up to the rim, too!
    Last edited by Selfsim; 2018-Jun-10 at 09:43 PM.

  4. #64
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    Quote Originally Posted by geonuc View Post
    The 1883 Krakatau eruption was plinian, not strombolian. While phreatic effects may have contributed to the overall sequence, the big eruption would have been due to a rapid buildup of pressure from degassing as fresh, hot magma was introduced into the magma chamber. That's my understanding.
    Then what about something like another Diamond Head?
    https://en.wikipedia.org/wiki/Honolulu_Volcanic_Series

    There is a part of me that wonders if this might be the last gasp of the 83' eruption, with everything becoming more quiet as the big island moves off the hot spot--or is that jumping the gun a little?

  5. #65
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    I'd suspect it's jumping the gun a lot. Geologic time is almost inconceivable to human minds. That's why we've got so many creationists.

    But thanks for the reminder to go look at the HVO site, I haven't since yesterday.
    Cum catapultae proscriptae erunt tum soli proscript catapultas habebunt.

  6. #66
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    Quote Originally Posted by publiusr View Post
    Then what about something like another Diamond Head?
    https://en.wikipedia.org/wiki/Honolulu_Volcanic_Series

    There is a part of me that wonders if this might be the last gasp of the 83' eruption, with everything becoming more quiet as the big island moves off the hot spot--or is that jumping the gun a little?
    Well, since the Pacific Plate is chugging away at 5 to 10 CM a year, it might be a bit too soon.

    Hawaiian volcanoes drift northwest from the hotspot at a rate of about 5–10 centimeters (2.0–3.9 in) a year.[18] The hotspot has migrated south by about 800 kilometers (497 mi) relative to the Emperor chain.[23] Paleomagnetic studies support this conclusion based on changes in Earth's magnetic field, a picture of which was engrained in the rocks at the time of their solidification,[45] showing that these seamounts formed at higher latitudes than present-day Hawaii. Prior to the bend, the hotspot migrated an estimated 7 centimeters (2.8 in) per year; the rate of movement changed at the time of the bend to about 9 centimeters (3.5 in) per year.[23] The Ocean Drilling Program provided most of the current knowledge about the drift. The 2001[46] expedition drilled six seamounts and tested the samples to determine their original latitude, and thus the characteristics and speed of the hotspot's drift pattern in total.[47]

    Each successive volcano spends less time actively attached to the plume. The large difference between the youngest and oldest lavas between Emperor and Hawaiian volcanoes indicates that the hotspot's velocity is increasing. For example, Kohala, the oldest volcano on Hawaii island, is one million years old and last erupted 120,000 years ago, a period of just under 900,000 years; whereas one of the oldest, Detroit Seamount, experienced 18 million or more years of volcanic activity.[21]


    The oldest volcano in the chain, Meiji Seamount, perched on the edge of the Aleutian Trench, formed 85 million years ago.[48] At its current velocity, the seamount will be destroyed within a few million years, as the Pacific Plate slides under the Eurasian Plate. It is unknown whether the seamount chain has been subducting under the Eurasian Plate, and whether the hotspot is older than Meiji Seamount, as any older seamounts have since been destroyed by the plate margin. It is also possible that a collision near the Aleutian Trench had changed the velocity of the Pacific Plate, explaining the hotspot chain's bend; the relationship between these features is still being investigated.[23][49]

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