Elucidating the Magma Plumbing System of the Active Volcano Ol Doinyo Lengai, Natron Rift, Tanzania Using Geodesy and Numerical Modeling
Abstract
The active volcano Ol Doinyo Lengai is located in the magma-rich southern eastern branch of the East African Rift and erupts unique low-temperature carbonatites. Between 2007 and 2010, the volcano had several explosions and erupted with ash falls, and lava flows ((VEI 3) and caused damage to the nearby community. Although this volcano has been studied for decades, its eruptive processes and plumbing system are still poorly understood, in part, because of the lack of precise observations of surface deformation during periods of unrest. Here, we seek to elucidate the volcanic plumbing system of Ol Doinyo Lengai using data from the permanent GNSS network monitoring the volcano called TZVOLCANO. First, we calculate velocities for 6 continuously operating GNSS sites distributed around Ol Doinyo Lengai between 2016 and 2021. Then, we compare the GNSS velocity solutions with Interferometric Synthetic Aperture Radar (InSAR) observations for nearly the same time-period. We then use the GNSS solution and InSAR observations to invert for the source(s) of observed surface deformation. Finally, we use the USGS code Coulomb 3.4 to forward model the observed deformation in the region and validate the best-fit model. Preliminary results suggest the presence of two magma sources generating surface deformation beneath Ol Doinyo Lengai.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2021
- Bibcode:
- 2021AGUFM.G24B..05D