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Sunday, May 6, 2018

UPDATE ON VOLCANO ERUPTION IN HAWAII

Yes, the eruption in Puna on the Big Island is continuing, but there have been no deaths.  The number of fissures has doubled to twelve, and ten or so homes (number up to 25 later in the day) have been destroyed.  Last night a lava fountain of 230 feet was reported, the highest yet.  Note, however, that this housing tract is located in the middle of the very active East Rift Zone.

You can only wonder how Leilani Estates came to be.  In 1955 and 1960 serious eruptions occurred down the fault line in Kapoho, less than 10 miles away.  But in 1964 this subdivision was created, bestowed as the royal child or heavenly lei.  To quote:

Leilani Estates is a beautiful, rural subdivision in the Puna District on Hawai'i Island.  Our Community has well-maintained, paved roads, one-acre lots, an active Neighborhood Watch program, Community Emergency Response Team (CERT), and a volunteer Board of Directors. 


There is a Community Center with a multipurpose Pavilion, playground, fitness trail, ball fields and meeting facilities. We have a variety of weekly activities and classes available to Leilani Estates residents. 

Leilani Estates is close to Pahoa Town, a quaint town with an eclectic mixture of old and new. There is a variety of services, shopping and restaurants in Pahoa, including post office, banks, healthcare, an all-purpose community park and community pool. Down the road there are plenty of ocean activities with parks, swimming, snorkeling, fishing, surfing and even a hot pond heated by the Volcano. Leilani Estates is approximately 30 minutes south of Hilo and an hour from Volcanoes National Park


Then in 1983, Pu'u O'o crater formed, uphill, where one flow for months threatened the town of Pahoa, which is NOT ON THE RIFT ZONE.  This latest eruption skipped under Pahoa and vented right in the middle of Leilani Estates.

While you can deprecate the stupidity of the owners and laws to allow this development, 45 years ago the Hawaii Geothermal Project, of which I was a member, selected the site of HGP-A to be on this fault line, a mile or so from Leilani Estates, because that spot was deemed by geophysicists as the optimal point to do the drilling.  However, our 3 megawatt well, which, by the way, was then the hottest geothermal find ever, was experimental.  Why Puna Geothermal Ventures built their 38 MW facility close by makes some scientific sense, but was that financially and logistically smart?

The frustration and agony are compounded by USGS volcanologists just uncertain about what is next to occur.  They have no clue if the 6.9 earthquake was as large as it will get, or if the next fissures will destroy the Puna Geothermal Venture power plant.  But that is the nature of this science.  As we don't know much about dark matter, we still can't predict the whims of Madame Pele.

However, the Island of Hawaii remains open for business.  TV channels across the world report on burning homes and lava covering roads, and the Hawaii Visitors' Bureau is concerned that tourists will stop coming.  You are at this moment not allowed to enter the Hawaii Volcanoes National Park, and much of the lower Puna area.  However, the rest of the island is safe.  But what about the whole island falling into the ocean?  Won't happen, trust me.

But, to continue my story regarding mega-tsunamis caused by rift faults and massive landfalls into the deep ocean triggering these monstrous tsunamis, perhaps 100,000 years ago such a cataclysm probably occurred in Hawaii when part of the Kohala area dropped into the sea, causing seawaters to rise up the slopes of mountains on Lanai and Molokai to 1500 feet.  Only 73,000 years ago a flank of West African Fogo Volcano collapsed into the ocean and the nearby island of Santiago (left) experienced a 560-foot mega-tsunami.

To close, I live on Nuuanu Avenue on the Island of Oahu in Hawaii.  From my book, but extracted from a posting on this site:

A particularly good example is the collapse on Oahu of Koolau Volcano a million years ago (give or take 500,000 years). Known as the Nuuanu Landslide or Nuuanu Debris Avalanche, where an apparent earthquake caused one third of the island to break off and fall into the sea. This might have been the largest landslide in the history of the planet, for just one chunk, known as the Tuscaloosa Seamount, is 20 miles (32 km) by 11 miles (18 km) and just more than one mile (1.8 km) high, and is located 60 miles (96 km) northeast of the Nuuanu Pali at a depth of 8800 feet (2680 m). As you drive towards Kaneohe/Kailua through the Pali or Wilson Tunnels and look back at the mountains, what you are viewing is that inside portion of the volcano that remained, although over the years, there has been considerable erosion and land build-up. A web page by Paul Jokiel of the Hawaii Institute of Marine Biology provides good info (Google search: “Jokiel’s illustrated scientific guide to Kaneohe Bay, Oahu”).


Kenji Satake of the Japan National Institute of Advanced Industrial Science and Technology reconstructed the event and surmised on the resultant tsunami from computer models using digital bathymetric data obtained on cruises commissioned by the Japan Marine Science and Technology Center. Estimated were: volume of 3000 km3 and velocity range from 20 m/s to 100 m/sec. Calculated tsunami heights were 100 meters (328 feet) in north Oahu, but 30 meters (98 feet) on the opposite side of the island, Waikiki. Five hours after the slide, 10-40 meters hit the Pacific Northwest and 30-70 meters in California, and in eight hours, 5-10 meters on the Japanese coast. Satake indicated that the wave heights could well have been double those sizes in the Hawaii Islands. So, a noted scientist did write about the prospects of a mega-tsunami in the far field from a landslide.

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