Geodetical and seismological evidences of stress transfer between Mauna Loa and Kilauea

Different studies evidenced an anticorrelated pattern behavior the activity of Mauna Loa and Kilauea  volcanoes. We quantitatively demonstrate the existence of this pattern by using DInSAR SBAS time series, areal strain of horizontal GPS components and the spatial distribution of hypocenters. The DInSAR time series have been studied by using the Independent Component Analysis (ICA) statistical algorithm revealing an anticorrelated ground deformation pattern between sources located at shallow depths beneath Mauna Loa and Kilauea. Furthermore, ICA showed another independent source beneath Kilauea alone, being located at greater depth. A similar pattern was observed in the time series of areal strain of GPS data as well as by spatial distribution of earthquakes depths.

The anticorrelated behaviour of both volcanoes, has been explained by the crustal-level interaction of pulses of magma that cause pressure variations in shallow magma system [1]. Another explanation for this peculiar behaviour is due to the interaction by pore pressure diffusion in a thin accumulation layer of the asthenosphere [2]. Geochemical and petrological studies [5] however, points at the existence of separate reservoirs for Mauna Loa and Kilauea.

The aim of this work is to explain the mechanism that allows the crustal-level relationship between shallow ground deformation sources of both volcanoes. We applied inverse modelling to determine the geometries of the magmatic reservoirs beneath Mauna Loa and Kilauea and their dynamics. This method revealed to be a useful tool to better understand the dynamics and represent the interaction between Mauna Loa and Kilauea.  

Our results indicate that the interaction between ground deformation sources of Mauna Loa and Kilauea occurs at shallower depths, therefore we excluded a direct interconnection between their magmatic systems and, instead, we postulate a stress transfer mechanism that explain this interaction. This mechanism has been postulated by several authors to explain the intrusions along rift zones and the interaction between earthquakes and eruptions in these two volcanoes [3, 4]. The magma ascent in Mauna Loa edifice creates a stress field in Kilauea which makes more difficult for the magma to ascent into its shallower reservoir. The same mechanisms could act in an opposite scenario.

[1] A. Miklius and P. Cervelli, “Interaction between Kilauea and Mauna Loa,” Nature, vol. 421, no. 6920, pp. 229–229, 2003.

[2] H. M. Gonnermann, J. H. Foster, M. Poland, C. J. Wolfe, and B. A. Brooks, “Coupling at Mauna Loa and Kilauea by stress transfer in an asthenospheric melt layer,” Nat. Geosci., vol. 5, no. 11, pp. 826–829, 2012.

[3] P. Amelung, F., Yun, S.H, Walter, T. and Segall, “Stress Control of Deep Rift Intrusion at Mauna Loa Volcano, Hawaii,” Science (80-. )., vol. 316, no. MAY, pp. 1026–1030, 2007.

[4] D.A. Swanson, W. A. Duffield, and R.S. Fiske, “Displacement of the south flank of Kilauea Volcano: the result of forceful intrusion of magma into the rift zones,” U.S. Geol. Surv. Prof. Pap. 963, p. 39 p.1976.

[5] J.M. Rhodes and S. R. Hart, “Episodic trace element and isotopic variations in historical mauna loa lavas: Implications for magma and plume dynamics,” Geophys. Monogr. Ser.,vol. 92, pp. 263–288,1995.