Diana Roman Matthew Burgess 2021 <p><span>“Surges” in magma supply from the mantle can lead to significant changes in eruptive behavior, thus their early identification is critical to long-term eruption forecasting. Here, we document and analyze two order-of-magnitude increases in seismicity in the upper mantle beneath southern Hawaiʻi between 2015 and 2020. We interpret the anomalous seismicity, which involved the rapid formation of new multiplets and a change in fault-plane solution orientations relative to pre-2015 events, as reflecting a substantial increase, or “surge” in mantle-derived magma, and we suggest that the intruded magma has been driving concurrent unrest at Mauna Loa, Kīlauea, and Lōʻihi Volcanoes through mechanical stress transfer.</span></p> application/pdf 10.1029/2020GL091096 en American Geophysical Union Ongoing (2015-) magma surge in the upper mantle beneath the Island of Hawaiʻi article