PhD Studentship: Modelling Near Surface Variations for Gravity Surveys

Understanding what is buried in the ground and what is the condition of the ground (soft areas, low density) is vitally important to deliver safe and in budget construction projects, especially large projects such as HS2 and Crossrail and reduce the risk due to buried hazards such as mineshafts. More importantly, this knowledge is essential if the underground space is going to be utilised more effectively in the future to free up surface space for green developments. Several different technologies exist to see through the ground, but many rely on transmitting an electromagnetic wave through the ground which is then reflected off a buried pipe or cable with the reflected signal received at the ground surface. However, the ground, especially wet clay, can make it really difficult to see anything deeper than a few centimetres. Thus, an alternative technology such as micro-gravity needs to be utilised. This technology measures the gravitational field of the subsurface by measuring density variations, but existing sensors are affected by the density of surrounding buildings or features, vibration from traffic and wind and ocean tides, to name but a few. This limits the possible resolution, i.e. smaller objects cannot be detected.

One key issue is the spatial variability of the near surface. Understanding soil and made ground heterogeneity and its impact on gravity surveys are important. It could be used to support modelling and prediction, and then tested when Quantum Technology (QT) instruments as developed by the QT Hub are ‎available. Therefore, this project will focus on understanding the variability of the soil, especially in the top 2m below the ground surface and assess its impact on gravity measurements, in particular the forward modelling and the inversion of data. The project will combine theoretical assessments with computer modelling and field trials. Close collaboration with the QT Hub in Sensors and Metrology (http://www.birmingham.ac.uk/generic/quantum/index.aspx) led by Birmingham is expected as well as collaboration with the British Geological Survey.

Therefore, if you are interested working across disciplines (e.g. geotechnical engineering, physics, electrical engineering, computer science), are highly motivated, adaptable and a good communicator, this might be a PhD project for you.

Interested applicants should contact the project supervisor, Dr Nicole Metje, for an informal discussion.

To find out more about studying for a PhD at the University of Birmingham see http://www.birmingham.ac.uk/undergraduate/courses/applicant-information.aspx.

Funding Notes

This research project is one of a number of projects at this institution. It is in competition for funding with one or more of these projects. Usually the project which receives the best applicant will be awarded the funding. The funding is for UK home fees and a stipend.

Overseas Students: If you have the correct qualifications and access to your own funding, either from your home country or your own finances, your application to work on this project will be considered.