UCL Earth Sciences


Interview with Dr Ashley Stanton-Yonge Sesnic

23 January 2024

As one of the assignments in the year one “The Earth” course, students conduct interviews with researchers in the department and write “Meet your researcher” newsletter-style article. Written by: Harry Wilkins, Jacob Coyle, Naadiyah Begum, Nick Cheung, Ishita Chauhan

Dr Ashley Stanton-Yonge Sesnic

Dr Ashley Stanton-Yonge Sesnic, a research associate at UCL, focuses on structural geology and rock physics. She studied engineering as an undergraduate where she had the opportunity to take an introductory geology course. Upon falling in love with the subject during fieldwork she decided to complete a masters in structural geology.

When you go into the field and some professor explains to you mountains, in the context of how they were formed, and you start understanding the landscape in a different way, there is no turning back.

Her passion led her to a PhD focusing on transfer of fluid through fracture networks and she now conducts research on rock deformation and fluid flow. She currently works on a machine that compresses rocks in three dimension to provide more realistic environments for conducting tests. Her favorite rock is Mylonite due to the beautiful patterns it develops as it forms!

PhD Research:

Dr Ashley Stanton-Yonge Sesnic research

Ashleys most recent publication was the article about ‘The Hydro-Mechanical Properties of Fracture Intersections: Pressure-Dependent Permeability and Effective Stress Law’. From which the main take away is, “The intersections between fractures might be the primary pathways for fluid flow when subjected to a lot of pressure at depth.” This essentially states under extreme pressure due to depth the small tube-like intersections of two fractures are responsible for the greatest portion of fluid flow.
Thus indicating fluid flow through rock at depth is primarily controlled through fracture intersections rather than the quantity of fractures themselves. A ‘tube-like’ intersection is illustrated above: (Stanton-Yonge et al., 2023)

Fieldwork and Experiences

Dr Ashley Stanton-Yonge Sesnic research
Before her PhD Ashley visited the Atacama Desert (pictured left) in Northern Chile where “beautiful faults” and “great geology” are found in the kilometers of exposed rock which have suffered minimal erosion due to the arid environment.

Ashley’s favorite aspect of research is the freedom to focus on her passions and feel proud of the data she produces. All research areas are enjoyable to her such as the lab and theory; however nothing is quite like the field where she is able to experience her findings and their impact.

An interesting place Ashley’s research took her is Iceland. Its location, at a tectonic triple junction, makes the area highly geothermally active. She observed hot water being piped from geothermal hotspots straight into showers, she commented on the noticeability of the sulfur smell.

Ashley’s research was conducted over 2.5 years and 40 different experiments, it’s the proudest achievement of her career. She encountered many challenges and “there was a long learning curve until (she) managed to get good results.” In short her research measured the flow of fluid through a basalt, she compared howpermeable rocks were with different fracture patterns (varying quantity and quantity of intersections) and how pressure effected this. Her findings will greatly improve computer simulations of fluid flow in the earth’s crust.

Research applications

Dr Ashley Stanton-Yonge Sesnic research

The improved modelling as a result of Ashleys research has many applications. She was particularly excited by geothermal exploitation and ore deposit exploration. With the former she feels she's making a difference as efficient geothermal operations will be more cost effective and safe,” That’s very nice! That’s what we all want!” Further, the application of her research to enhanced geothermal systems, pictured right, (Olasolo et al., 2016) could enable greater exploitation of this resource and she believes it might potentially form part of a solution to the global energy crisis. On top of this, "the implementation of realistic fluid flow models... has numerous practical applications including... carbon dioxide storage and the underground disposal of radioactive nuclear waste” (Stanton-Yonge et al., 2023, n.p.). For more information of enhanced geothermal systems, visit



  • Olasolo, P., Juárez, M.C., Morales, M.P., D´Amico, S. and Liarte, I.A. (2016). Enhanced geothermal systems (EGS): A review. Renewable and Sustainable Energy Reviews, 56, pp.133–144. doi:https://doi.org/10.1016/j.rser.2015.11.031.
  • Stanton-Yonge, A. (2023) Interviewed by Begum, N., Cheung, N., Chauhan, I., Coyle, J. Wilkins, H. 12th October, London.
  • Stanton-Yonge, A., Mitchell, T.M. and Meredith, P.G. (2023). The Hydro-Mechanical Properties of Fracture Intersections: Pressure-Dependant Permeability and Effective Stress Law. Journal of Geophysical Research: Solid Earth 128(2). doi:https://doi.org/10.1029/2022jb025516. 
  • UCL (n.d.) Dr Ashley Stanton-Yonge Sesnic Research Profile