Imperial College London

MissHelenLacey

Faculty of Natural SciencesThe Grantham Institute for Climate Change

Research Assistant
 
 
 
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Contact

 

h.lacey14 CV

 
 
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Location

 

2.49AARoyal School of MinesSouth Kensington Campus

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Summary

 

Summary

I am a PhD student in the department of Earth Science and Engineering. The focus of my work is to better constrain the representation and role of cementation in fault zones.

The cyclic fluid system induces significant changes in the strength and behaviour of fault zones, which has vast implications from reservoir longevity to earthquake recurrence intervals.

I utilise methods of stable isotope geochemistry and microscopy to study cements in fault zones, precipitation laboratory experiments and modelling to gain insight into cementation processes over the course of the earthquake cycle. Stable carbon and oxygen isotope ratios in cement phases are determined to derive information on the fluid source and thus the migration of fluids, as well as interactions with the surrounding rock. These geochemical signatures could also provide evidence on whether a feature is actually related to fault movement, which can be difficult to determine in the field. Field descriptions and conventional and cathodoluminescence (CL) microscopy permit the analysis of the textures and cement generations. Laboratory based precipitation followed by strength and permeability characterisation using standards and host rock from real fault zones allows us to see changes in rock properties based on the mechanism of precipitation. These studies present scope to link together the geochemistry of cements with the mechanical effects on a fault in a multidisciplinary approach.

Publications