G11C-07
Deep and shallow sources for the Lusi mud eruption revealed by surface deformation
Monday, 14 December 2015: 09:30
2002 (Moscone West)
Manoochehr Shirzaei, Arizona State University, School of Earth and Space Exploration, Tempe, AZ, United States, Maxwell L Rudolph, Portland State University, Geology, Portland, OR, United States and Michael Manga, University of California Berkeley, Berkeley, CA, United States
Abstract:
The Lusi mud eruption, near Sidoarjo, East Java, Indonesia, began in May 2006 and continues to the present. Previous analyses of surface deformation data suggested an exponential decay of the pressure in the mud source, but did not constrain the location, geometry and evolution of the possible source(s) of the erupting mud and fluids. To map the surface deformation, we develop and new multitrack multitemporal interferometric processing algorithm and apply it to overlapped zones of three well-populated SAR data sets, including 51 images and acquired by the ALOS L-band satellite between May 2006 and April 2011. To understand the spatiotemporal evolution of the mud and fluid sources, we then apply a time-dependent inverse modeling scheme. Volume changes occur in two regions beneath Lusi, at 0.3-2.0 km and 3.5-4.75 km depth. The cumulative volume change within the shallow source is ~2-3 times larger than that of the deep source. The observation and model suggest that a shallow source plays a key role by supplying the erupting mud, but that additional fluids do ascend from depths >4 km on eruptive timescales.
