Mark Jefferd

Mark Jefferd

Profile Display Name:
Mark Jefferd
E-mail Address:
Start Year

2015 (Cohort 2)

Research interests:
Hobbies and interests:

PhD Project
PhD Title
A laboratory and field based study into the deformation of sandstone under hydrothermal conditions: implications for fluid flow within the crust
Research Theme
Solid Earth Dynamics
Primary Supervisor

Nicolas Brantut

Primary Institution
Secondary Supervisor

Phil Meredith

Secondary Institution

With increasing depth in the crust, the deformation mode of porous rocks transitions from brittle faulting at shallow depths, to cataclastic flow at greater depths. While the pressure dependence of this transition is reasonably well constrained, much less is known on the effect of temperature. To date very little work has been done to assess the impact that a temperature increase has on the transition from shear localisation and brittle faulting to cataclastic flow. At elevated pressures, porous rocks typically deform by compactant cataclastic flow; this mode of deformation has recently been shown to be time dependant, due to the chemical water-rock interaction. Temperature and fluid chemistry are expected to strongly effect the compaction rate, but there is currently no data documenting these effects. My study will utilise a new triaxial deformation press, to deform sandstone under triaxial conditions at pressures and temperatures found within the upper 6km of the crust. The response of the porosity, permeability and the development of microstructures within the rock will be measured and compared to data gathered from the field.

Policy Impact
Background Reading


Social Links
University Departmental Website:
Personal Website:

Stay informed

Click here to subscribe to our RSS newsletter by email.

Find Us

University College London is the administrative lead.

Pearson Building, UCL, Gower Street, London, WC1E 6BT

Follow us on Twitter