Schematic east-west cross-section across Kīlauea caldera 2018-2019

Schematic east-west cross-section across Kīlauea caldera. Cartoon is not to scale, and features are greatly exaggerated for clarity. (A) Prior to the 2018 collapse, the summit eruptive vent was supplied by the Halemaʻumaʻu magma reservoir, 1–2 km beneath the caldera. (B) Collapse of the summit occurred due to drainage of the Halemaʻumaʻu reservoir to feed a lava eruption on the LERZ, resulting in the creation of void space at the summit. (C) During the time spanned by the two gravity surveys, magma accumulation in void space led to a gravity increase (blue arrows) without significant surface uplift. (D) After March 2019, magma accumulation was sufficient to cause both a gravity increase (blue arrows) and surface inflation (black arrows) due to pressurization in the Halemaʻumaʻu magma reservoir. From Poland and others (2019): https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2019GL084901.