Current Research in Earth, Environmental and Planetary Sciences: Sin-Mei Wu, University of Utah
Spatiotemporal Study of Naturally Eruptive Systems Using Seismic Interferometry and Dense Nodal Arrays
Volcano and geyser eruptions are powerful, which requires significant energy accumulation within the system before unrest becomes evident. Because such internal processes are weak and commonly obscured by nearby hydrothermal/volcanic activity, we designed and deployed seismic nodal arrays and developed interferometric-based methodologies necessary to understand the dynamics of the naturally eruptive systems. In this talk, I will present the investigations of spatiotemporal properties of seismic source and velocity structure at three different systems –– Old Faithful, Steamboat Geysers in Yellowstone, and Kīlauea Volcano in Hawaii.
For Old Faithful, we imaged the shear-wave velocity structure associated with the encompassing geologic deposits, discovered the large reservoir, and revealed how the geyser formation is controlled by local geology and fluid pathways. By constraining the 4D origin of hydrothermal tremor from bubble collapse/nucleation, we illuminated the first view of Old Faithful’s deep conduit to 80-m depth and its recharge evolution with minutely resolution.
For Steamboat, we simultaneously constrained the 4D tremor origins for Steamboat and the nearby hydrologically-connected spring, Cistern. The results construct the first image of the plumbing architecture for the Steamboat-Cistern system to 140-m depth and reveal the distinct recharge evolution in between, indicating the two systems might connect through a porous medium.
For Kīlauea Volcano, we resolved spatiotemporal seismic velocity variations associated with new subsurface dike emplacement and magma movement within. The changes in velocity are associated with crustal damage, relaxation, and strengthening at different volcanic components (i.e., summit, dike, and fissure), suggesting that the elastic properties in the shallow crust varied in concert with magma dynamics. Our findings provide constraints on the evolution of Kīlauea’s subsurface structure during its major eruption.