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Ben Gaddis

Publications and source records attributed to Ben Gaddis.

5 recordsLinked to original sources

Small-volume tephra deposits of the May 1924 explosions from Halemaʻumaʻu, Kīlauea volcano, and their origin

More than 50 explosive eruptions occurred from Halemaʻumaʻu at Kīlauea volcano over 17 days from May 11 to 27, 1924. Ballistics weighing as much as 14,000 kg were ejected and most landed within 2 km of the vent. Fine ash made up a major component of the tephra and was dispersed tens of kilometers downwind. Draining of the Halemaʻumaʻu lava lake occurred in late February 1924, with the crater floor eventually subsiding by a further ∼70 m (to ∼180 m below the crater rim) by the time the first explosions took place during the night of May 10–11. The largest explosions occurred on May 17–18 and smaller explosions continued until May 27, at which point Halemaʻumaʻu had more than doubled in width and depth. The explosions generated plumes reaching up to ∼10 km high with ballistics ejected up to 2 km from the crater. Almost 100 years later, we investigate and characterize the preserved tephra deposits within ∼3 km of the 1924 crater rim. Grain size and shape analyses were performed on 202 samples collected from 34 tephra profiles using dynamic image analysis, with a subset of layers from nine tephra profiles used for componentry (200 grains per layer in the 0.5–1 mm size fraction). Additionally, we characterize the average diameters (using the five largest clasts) at 216 locations and measure the average diameters of 2291 ballistics (largest per ∼100 m 2 area). Physical descriptions from fieldwork and grain size distributions were used to subdivide the tephra layers into five lithofacies: coarse homogeneous, fine homogenous, red ash, accretionary lapilli-bearing, and finely laminated. Grain size versus shape data show a range of values that demonstrate most grains are dense, smooth, and equant, in alignment with lithic clasts dominating the tephra componentry. The fine grained and accretionary lapilli-bearing nature of some of these lithofacies confirms that water influenced the style of the explosions. However, we also note juvenile clasts within many of the tephra layers, indicating that many of the layers were formed during phreatomagmatic explosions (sensu stricto), despite the eruptive mechanism being dominantly phreatic. Juvenile clasts are more abundant higher in the tephra profiles, suggesting that juvenile magma was more involved later in the explosive sequence. Thermal and hydrologic modeling indicate that groundwater inflow into a short-lived, small-diameter volcanic conduit (10-m to 120-m-diameter used for modeling) during the 78–85 days preceding the first explosion provides a physically plausible mechanism for this eruptive sequence.

Hawaii↗

Views of a century of activity at Kīlauea Caldera—A visual essay

The 2018 eruption of Kīlauea Volcano marked the end of the first sustained period of volcanic activity at Halemaʻumaʻu Crater in 94 years. The views of the lava lake (informally named “Overlook,” nestled within Halemaʻumaʻu) lasted for a decade and seemed timeless. But as we were recently reminded, the summit of Kīlauea is part of a dynamic system that has provided countless new views to observers over the centuries. This visual essay features a few of the many scenes recorded by early observers at the volcano, from the first visits by westerners in 1823 through the explosive eruption of 1924. The early images left by casual visitors, artists, and photographers raise many questions: What is shown? Where is this? Who captured the scene and when? How accurate is the portrayal? Where possible, we attempt to answer these questions and provide interpretations of the images featured. In 1912, the nature of observations at Kīlauea changed when Thomas A. Jaggar, Jr., and others occupied the Hawaiian Volcano Observatory on a full-time basis. They began a visual and written record of what they saw, heard, and experienced that has continued to this day. We describe some of the early work of these scientists and photographers, and showcase the results.

Hawaii↗

Correcting the historical record for Kīlauea Volcano's 1832, 1868, and 1877 summit eruptions

Three fissure eruptions are known to have occurred along the northeastern edge of Kīlauea's summit caldera in the 19th century—in the years 1832, 1868, and 1877. Modern portrayal of these eruptions on maps and in written sources indicates that the 1832 eruption was from a fissure on the side of the Poliokeawe scarp south of Byron Ledge, the 1868 eruption was from a fissure on the southern wall of Kīlauea Iki Crater and fed a lava flow that covered the bottom of that crater, and the eruption in 1877 occurred on the floor of Keanakākoʻi Crater, as well as from a fissure of uncertain location on the east wall of the caldera below Byron Ledge. New geologic mapping and a review of historical documents and maps contradict these views. We find, instead, that: (1) the 1832 eruption discharged from a fissure on Byron Ledge (not Poliokeawe scarp), from another fissure on the southwestern wall of Kīlauea Iki Crater, and from at least one fissure along the east side of Kīlauea caldera below Byron Ledge; (2) the 1868 lava erupted through the floor of Kīlauea Iki Crater, not from a fissure in its southwestern wall; and (3) the 1877 lava erupted from Kīlauea Iki Crater's mid-wall fissure (until now believed to have opened in 1868), from the fissure previously assigned an 1832 date on Poliokeawe escarpment, and from a precisely relocated vent on the northeastern wall of the caldera. Finally, no conclusive first-hand accounts of the late 19th century eruption in Keanakākoʻi Crater were identified, leaving in doubt the often-inferred 1877 date for this event. Possible alternative dates include 1868, 1879, and 1881.

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The lava flow that came to Hilo—The 1880–81 eruption of Mauna Loa volcano, Island of Hawai‘i

The Mauna Loa eruption sequence of 1880–81 consists of two eruptions. The May 1880 eruption in Mokuʻāweoweo at the summit of Mauna Loa lasted just a few days and was followed 6 months later by three lava flows that issued from vents along the Northeast Rift Zone. The November 1880 eruption lasted almost a year and one of its flows nearly reached Hilo Bay. Public reaction in Hilo to the advancing lava flow increased as the lava got closer, but a smallpox quarantine prevented travelers and government officials from leaving Honolulu, the government seat of the Hawaiian Kingdom, until July 1881. In the King’s absence, his sister Princess Regent Liliʻuokalani and key officials met in Hilo at the beginning of August to plan a government response. This included the first known plan to use barriers and explosives to divert the lava flow in Hawaiʻi. Fortunately, the lava flow stopped before the plan was enacted; however, both Christian prayer and traditional Hawaiian chants and gifts to the Hawaiian deity Pele were offered in the last few weeks of lava activity. Mauna Loa was again restless in 2019 and the time seems optimum to review this and other Mauna Loa flows, in order to be ready for the next lava flow. Should the next flow threaten developed areas, review of past lava flow threats may provide valuable experience on how the public may best be provided with information.

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Volcano art at Hawai`i Volcanoes National Park—A science perspective

Long before landscape photography became common, artists sketched and painted scenes of faraway places for the masses. Throughout the 19th century, scientific expeditions to Hawaiʻi routinely employed artists to depict images for the people back home who had funded the exploration and for those with an interest in the newly discovered lands. In Hawaiʻi, artists portrayed the broad variety of people, plant and animal life, and landscapes, but a feature of singular interest was the volcanoes. Painters of early Hawaiian volcano landscapes created art that formed a cohesive body of work known as the “Volcano School” (Forbes, 1992). Jules Tavernier, Charles Furneaux, and D. Howard Hitchcock were probably the best known artists of this school, and their paintings can be found in galleries around the world. Their dramatic paintings were recognized as fine art but were also strong advertisements for tourists to visit Hawaiʻi. Many of these masterpieces are preserved in the Museum and Archive Collection of Hawaiʻi Volcanoes National Park, and in this report we have taken the opportunity to match the artwork with the approximate date and volcanological context of the scene.

Hawai'i↗