EAPSI:Investigating Magma Ascent Rates and Eruption Styles at Kîlauea Volcano Using Diffusion Modeling of Element Zoning in Olivine Crystals

Lynn Kendra J, Honolulu HI

Investigators

Abstract

Modern activity at Kîlauea Volcano (Hawai'i) has been dominated by effusive lava flows and spectacular fountaining events. However, recent work reveals a history of explosive eruptions, which killed large numbers of Hawaiians near the volcano's summit. These eruptions were drastically different compared to modern activity that has made Kîlauea seem like a relatively safe, quiet volcano. To understand and predict the frequency and style of volcanic eruptions at basaltic volcanoes like Kîlauea, knowing the amount of time magma resides within the volcano is crucial. This work will use the chemical composition of the most common mineral from Kîlauea (olivine) to determine how quickly magma ascends to the surface for explosive versus effusive eruptions. Comparing magma storage histories for different eruption types will contribute to understanding the long-term evolution of Kîlauea's magmatic plumbing system. Most importantly, this work will address how and when hazardous explosive eruptions can occur. The study will be conducted at Nanyang Technological University in collaboration with Dr. Fidel Costa Rodriguez, a leading researcher using olivine chemistry to calculate magma residence times at volcanoes around the world. This project aims to (1) characterize magma residence times for two summit reservoirs at Kîlauea using recent effusive eruptions, and (2) evaluate the relationship between olivine residence time and eruption style by comparing diffusion histories from effusive and explosive eruptions. Major and minor (electron microprobe), plus trace (laser ablation mass spectrometry) element analyses of olivine crystals, in combination with crystallographic orientations (electron backscatter diffraction), will be used as model inputs to calculate residence times of olivine in eruptions of different styles and chemistries. Timescales will be determined using a finite difference diffusion modelling scheme. The volcanic implications will enhance understanding of the dynamic nature of Hawaiian volcanoes. This NSF EAPSI award is funded in collaboration with the National Research Foundation of Singapore.