Rift Volcanism: Past, Present and Future [RiftVolc]

Kathy Whaler
2020
Rift Volcanism: Past, Present and Future [RiftVolc]
This is a Full Scientific Report resulting from NERC Geophysical Equipment Facility Loan 1036, principal investigator Prof Kathy Whaler.

Abstract

As part of a survey of the resistivity structure of the central main Ethiopian rift we used the GEF TEM and solar panels in 2016, and just solar panels in 2017. Solar panels were used to power magnetotelluric (MT) systems borrowed from Dublin, Ireland. The equipment performed as expected but the MT data quality was only average owing to significant civil unrest at the times of our surveys. Nevertheless our 2016 data were sufficient to publish a 2D cross-rift profile model, and we are in the process of preparing a manuscript on a 3D model of a broader area; the latter was presented at the 2020 virtual EGU meeting. The western flank of the rift is associated with high conductivities, interpreted as abundant melt, whilst the restive Aluto volcano is underlain by a prominent resistor. Our 3D model has ubiquitous high conductivities in the lower crust, away from the Wonji fault belt to the southeast. The extent and location of this feature corresponds well with a low shear wave speed feature obtained from ambient noise tomography.