Studies of Recent Eruptive Phenomena at Kīlauea Volcano

Abstract

Kīlauea Volcano, on the island of Hawaiʻi, hosts a broad range of basaltic eruptive styles that have traditionally been studied with relatively sparse observations and data. Recent advances in digital camera and webcam technology, however, as well as improvements in the sensitivity and acquisition rate of geophysical data, offer new opportunities to study these processes. Here, robust visual and continuous camera observations are integrated with high-rate geophysical data in four studies, to enhance our understanding of eruptive activity at Kīlauea: (1) A brief eruption on Kīlauea’s East Rift Zone during 2007 led to a pause in the long-lived Puʻu ʻŌʻō eruption. Activity resumed with the refilling of the Puʻu ʻŌʻō crater, first by lava, and then by endogenous uplift. Filling culminated in the opening of a new eruptive fissure at Puʻu ʻŌʻō, marking the start of a new period of eruptive activity. (2) During 2010, lava flows advanced toward the Kalapana Gardens subdivision on Hawaiʻi’s southeast coast, eventually destroying three homes. As the relatively low-discharge flow advanced into this area, it was laterally confined by low topography. Subsequent inflation was focused over the lava tube that developed in the flow, forming a long, sinuous tumulus that snaked across the gently sloping terrain. The unusual feature may be an analog for similar lava flow structures identified in New Mexico and on Mars. In addition, the sinuous tumulus was the source of frequent breakouts associated with cycles of deflation and inflation at Kīlauea’s summit, providing a means of forecasting activity. (3) Kīlauea’s ongoing summit eruption has been punctuated by small, impulsive explosive eruptions since it began in 2008. High-rate webcam imagery shows convincingly that these explosive events were triggered by rockfalls from the vent walls that directly impacted the top of the lava column, generating a rebound splash (Worthington jet). (4) The March 2011 Kamoamoa eruption, preceded by months of precursory changes, was exceptionally well documented with an array of geological, geophysical, and geochemical observations. This multiparametric monitoring suggests that the eruption was driven by an imbalance between the magma supplied to and erupted from the Puʻu ʻŌʻō vent.