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Photo of Mr Louis Penfound-Marks

Mr Louis Penfound-Marks



Pegmatites have traditionally been considered synonymous with highly evolved, hydrous melts enriched in incompatible elements associated with the latter stages of fractional crystallisation of a spatially and temporally restricted magma batch in the upper crust. The transcrustal magma mush concept suggests a continuum of mush spanning the lower and upper crust, with subordinate fluid and melt distributed and interacting chemically with the enclosing 3D framework of crystal mush, an important mechanism by which the melt evolves.

The occasional supply of magma from elsewhere into the crystal mush may disrupt dominantly mush-like conditions, switching sufficiently to allow local pockets of magma to exist and be emplaced upwards and laterally to form transient zones of magma. Compaction of crystal mush associated with shearing represents an additional mechanism by which melt migration may be initiated and is compatible with the frequent spatial relationship between pegmatites and shear zones.

The Leinster pegmatite belt of County Wexford in SE Ireland represents a demonstration site of the GREENPEG Horizon 2020 project, which aims to develop new exploration tools for European pegmatite-hosted green technology resources. The study site is also being actively explored by junior exploration company, Blackstairs Lithium Ltd.

My PhD aims to reappraise the genesis of LCT pegmatites of the Leinster area in the context of the transcrustal magma mush concept with the aim of developing a new exploration model. The study will involve detailed core logging, mineralogical and petrographical studies as well as mineral-chemical-imaging studies.

My previous industry experience spans exploration geology and the design of special geotechnical measures and earthworks in the UK.

Academic Qualifications
BSc Applied Geology (2011-2014), University of Exeter (Camborne School of Mines) – 1st Class.
MSc Applied Geotechnics (2015-2016), University of Exeter (Camborne School of Mines) – Distinction.

Honours and Awards
CSM Undergraduate Scholarship (2011).
JC Industrial Geology Prize (2014) – for best undergraduate dissertation project.