Still working out kinks and learning. Helpful hints and criticism appreciated. Let me know if you do NOT want to receive these missives. And I think itʻs best, if can, if youʻd forward to friends and family. If humbug, let me know and Iʻll add them to The List.
Oh. And if you have Topics youʻd like info on, let me know.
OK. Allʻs quiet on the Eastern Front at the moment. Attached EQ graphic (earthquake or ʻōlaʻi). One for the Island of Hawaii showing the past week or so. The other is the LERZ (lower east rift zone) and has the legend. Things seem to have slowed a tiny bit at the distal (farthest) end of the Intrusive Dike. The ID is the blade-like body of magma that pushed into the LERZ starting on May 1 or so. Dikes are typically several feet wide and several kilometers tall. Boggles the mind, but there we have it. The blade of pele pushes through the volcanic edifice (the mountain), breaking rocks as she progresses = the smaller earthquakes.
Each intrusion is a separate dike, and they remain in the rift, parallel to, and sometimes adjacent and mixing with older dike material. Dikes remain molten for a LONG time. Many decades or more. Lava is a great insulator and doesnʻt conduct heat well, so in the ground, magma stays hot. Then when another intrusion comes along it may push older material to the surface. Thatʻs whatʻs happening now. Geochemists have determined that the lavas erupted in Keahialaka (the fire of Laka) in Leilani Estates, were emplaced in the neighborhood in 1955, during that 3 month eruption from multiple vents. Here again is a link to the report of that eruption:
Definitely worth at least browsing.
A detail of interest to me, and perhaps to you: lava erupted fresh from the source, the hotspot under our feet tens and tens of kilometers down, is HOT (2,000+ fahrenheit degrees), making it very fluid and flowable, usually as pahoehoe, as weʻve seen much of the last 30+ years. The skin freezes when it hits the air and the flow ends up with a silver, smooth, glassy surface. Pahoehoe in Hawaiian, also means "satin" like the fabric. Can you visualize it? If not, an attached pic might help.
But. If magma has been sitting around for many many decades, degassing, cooling slightly (remember how good an insulator lava is), when itʻs pushed to the surface, itʻs often dark, pasty, and kinda spooky looking. I know, I know...very subjective... THATʻS what been erupting in Keahialaka. Dark rough lava, often transitional combinations of aa and pahoehoe. And that "slight cooling"? Often just several degrees. Another pic or two are attached of these flows in Leilani Estates.
Hmmmm. Then we read AP reports and other national media saying that "Kilauea is about to Blow its Top!!!!!!!!!!!". Most unhelpful. Journalists write. They most often arenʻt geologists or other specialists. Their uninformed writing can be sensationalistic. Causing The Populace to rush out and buy face masks of various sorts, causing shortages of those devices. Again, I may be living in a Foolʻs Paradise, but I watch and sit and observe... I believe that Iʻm prepared as I can be without going nuts. Thank you Social Media...
Iʻll be taking a break for a bit, heading to Waimea to listen to the dulcet tones of Robert Cazimero, and hopefully relaxing. Back Sunday afternoon, paha.
Questions are more than welcome. And though I canʻt respond to all who thank me, I appreciate that you appreciate this. And in the midst of our excitements here, we still are reminded of our friends on the other end of the chain, on the north shore, especially, of Kauai. What to make of this...Lohiau at Kee, Pele here...
As always, with aloha,
Bobby
(808) 967-7787 (h)
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