Overview
Caldera volcanoes are complex and dangerous, and their highly explosive eruptions are infrequent but responsible for some of the most catastrophic geological events, with potentially devastating local, regional and global environmental and societal consequences.
About this opportunity
One of the major problems faced in volcanology is understanding the triggers of volcanic eruptions and how to recognize them. Key to solving this problem is improved understanding of volcanic plumbing system dynamics and how these impact the efficiency of magma mingling and mixing during ascent.
Despite magma mixing and mingling being identified as important potential triggers for large silicic caldera-forming eruptions, there is relatively little understanding about the physical processes involved and how they occur in a caldera setting. Geological field studies have provided important insights into the nature of magma mingling and mixing in the lead up to eruptions, though these are not often integrated with physical models.
A major obstacle to understanding magma ascent at caldera volcanoes is that the long-lived paradigm of a magma chamber sitting in the crust beneath a volcanic edifice is no longer the dominant model for explaining how volcanic eruptions are fed. Instead, the magma reservoir is now characterized as an interconnected network of magma-filled sheets, such as dykes and sills, hosted within a magma mush. As magma moves upwards through the crust it can interact with stalled magma bodies and encounter lithological complexities, such as mechanically distinct rock layering and faulting.
The 16 x 20 km Diamante caldera of the Southern Andean Volcanic Arc formed 167±8 ka, erupting ~350 km3 of rhyolitic ignimbrite and rating this as 7 on the Volcanic Explosivity Index. It last erupted in 1912 and has had at least seven eruptions in the past 100 kyr which have built the Maipo stratovolcano. Any future volcanic activity from Diamante-Maipo would impact health, global economics and resourcing of the green-energy transition as this active volcanic system is situated on the Chile-Argentina border, with Chile’s capital city, Santiago (population >5.6 m), the Mendoza Province of Argentina (population >1.2 m) and the largest underground copper mine in the world, El Teniente all nearby.
Objectives
The project aims to reduce the negative environmental and societal impacts of caldera unrest and eruptions by modelling the processes of magma ascent in a caldera setting and quantifying how these are affected by mingling and mixing of magmas at depth. This will be achieved through the following objectives:
- Complete a set of analogue experiments and apply state-of-the-art particle image velocimetry (PIV) to quantify the fluid dynamics of mixing and mingling in interconnected magma bodies. These experiments will be conducted at the MAGMA Lab, University of Liverpool using the Medusa Laser Imaging Facility.
- Develop new analogue modelling techniques to quantify mixing and mingling processes within an analogue ring fault, typical of caldera volcanoes. These experiments will be conducted with CASE partners at CSIC in Barcelona.
- Collect new field data and rock samples to characterize the nature of magma mixing and mingling in erupted deposits. Our target caldera volcano will be the Diamante-Maipo caldera-stratovolcano system of the Southern Andean Volcanic Arc.
Research Environment and Training:
You will become a member of the ACCE+ postgraduate research community and join the Liverpool Volcanology Group. Bespoke training will be provided in analogue modelling and igneous petrology as required.
Project CASE Status
This project is a CASE project. Your project will be co-supervised by the non-academic partner organisation, and you will spend 3-6 months on a placement with your CASE partner in their workplace. You will experience training, facilities and expertise not available in an academic setting, and will build business and research collaborations.