UCL Earth Sciences


Becca Strachan

“Modelling structurally controlled ore deposits.”

PhD project title:

Structural Controls on Fluid Pathways and Alteration in the Seismic Cycle of Porphyry Deposits in Chile.

Becca Strachan
Project description:

Chile is the world’s leading copper producer, home to 16 of the world’s largest porphyry deposits. These deposits are temporally and spatially constrained to specific structural tectonic belts which are the direct result of Chile’s complex and multiphase tectonic history. Understanding the fundamental fluid-rock interactions associated with hydrothermal fluid and magma transport in porphyry systems is essential in defining the controlling structure of these ore bodies. 

The overall aim of the project hopes to redefine the generalised porphyry model by considering the structural, spatial and temporal controls on alteration and fluid flow in the system. A 4D model will be produced that integrates the evolution of fault structure, magmatism and fluid flow, as a function of time. 3D models will be created by combining detailed structural fault/fracture and alteration field data with high resolution UAV ‘structure from motion’ mapping of major structures and alteration patterns. Samples collected from selected sites, based on alteration style and proximity from fracture networks, will be geochemically analysed to enhance the 3D model of the fracture-alteration spatial distribution from major structures. 

My primary interest is how ore deposits are spatially and temporally controlled by structural geology. I am fascinated by how tectonics can have such a crucial role in all stages of mineralisation; from initial fluid flow transportation, to an essential control for syn- and post- mineral deposition. Understanding these processes on a regional and deposit scale is vital to future mineral exploration and discovery of obscure and complex deposits.