Kaʻū News Briefs Friday Nov. 25 2016

THE ERUPTING VOLCANO, WATERFALLS, HAWAIIAN AGRICULTURE AND LOCAL CULTURE were main features representing Hawaiʻi Island on the float in the 90th Macy’s Thanksgiving Day Parade in New York City yesterday. Macy’s partnered with King’s Hawaiian sweetbread company to build the float. It showed coco palms, sugar, pineapple, plumeria and other flowers, along with a waterfall, a volcano spewing confetti, and a rural shack, picnic table and garden.    Two hundred hula dancers and the Hawaiʻi all-state marching band of 500 musicians, from public and private schools around the state, joined the parade seen by about 50 million people on television and the Internet, and three million people on the streets of New York City.       Macy's Thanksgiving Day Parade Executive Director Amy Kule said, “Hawaiʻi is a land of absolute wonder. The agriculture, the culture itself, the sheer beauty of this island is going to be shared with a brighter and bigger audience.” To read comments, add your own, and like this story, see Facebook. Follow us on Instagram and Twitter. Tahiti-based London Missionary Society missionary William Ellis and American missionaries observed and recorded activity at Kīlauea Volcano in the summer of 1823 during a walk around the coastline of Hawaiʻi Island.  Wikipedia image  VOLCANO WATCH: “AN ASSUMPTION ABOUT KĪLAUEA VOLANO is proven wrong,” is the headline of this week’s report from Hawaiian Volcano Observatory scientists. “Everyone extrapolates facts and makes assumptions based on those facts. Sometimes, such an assumption is repeated so often that it takes on the aura of a ‘fact’ itself. This is the story of how one such assumption about Kīlauea’s recent past was proven wrong – and only in the past couple of months!”

     Going back in the history of western arrival in Hawaiʻi, the scientists write that “William Ellis, leader of the first missionaries to visit Kīlauea, described numerous pieces of windblown pumice (‘spumous lava...as light as a sponge’) in hollows on the ground as he approached the summit from the southwest on August 1, 1823. This must be the golden pumice. How long before his visit did the pumice fall?”
    The scientists explain that, “Scattered remnants of a once-extensive pumice deposit occur on the ground surface west of Kīlauea Volcano’s summit caldera. The pumice, known as the golden pumice, records a large lava fountain in the southwest part of the caldera.

Golden pumice is seen here along with many other kinds of offerings from the volcano. USGS photo

     “In a study of the golden pumice published in 1987, three celebrated geologists – Bob Sharp (CalTech), Dan Dzurisin (USGS), and Mike Malin (Arizona State) – suggested an eruption date ‘possibly around 1820.’ The only rocks that fell later onto the pumice were, in their interpretation, erupted in 1924. They observed other thin deposits locally overlying (hence, younger than) the golden pumice but ascribed them to remobilization of older deposits by water, rather than to younger eruptions.
     “These observations and interpretations led to the assumption – challenged in this Volcano Watch – that the golden pumice represents the youngest explosive eruption from the caldera until 1924.
     “Several years ago, another pumice bed, called the eastern pumice, was discovered in the southern part of Kīlauea’s caldera. It underlies, and therefore is older than, explosion deposits consisting largely of rock fragments, not pumice.
     “Work on the eastern pumice – see Volcano Watch for August 8, 2013 (http://hvo.wr.usgs.gov/volcanowatch/view.php?id=188)– tracked it westward into golden pumice
country. Nowhere, however, could we find the two deposits in the same outcrop, so we could not determine if the golden pumice was truly younger than the eastern pumice, as was assumed.
     “We looked in just the right place and found clear physical evidence of  two pumice layers, one on top of the other. The older, lower pumice has the golden pumice composition. A chemical analysis of the younger, upper pumice, which looks physically like eastern pumice, was completed in late October, and it is indeed eastern pumice. The outcrop was examined once more in November with neutral observers, just to be sure, and the field relations were confirmed.

     “This discovery upsets the apple cart. The assumption is wrong that the golden pumice records the last 19th-century explosion.