Geology and Geophysics Staff
Prof Tim A Minshull
- Telephone
- External: +44 (0) 23 80596569
- Internal: 26569
Specialism
Marine geophysics
Research Interests
My research focuses on the application of marine geophysical techniques, and in particular controlled source seismology, the study of geological processes in the oceans and on their margins:
This is my main area of research, with a particular focus on magmatic and tectonic processes occurring in the final stages of continental breakup. For many years I have worked on the West Iberia margin, where mantle rocks were exhumed to the seafloor during these final stages and the processes involved are documented by extensive geophysical datasets and drilling by the Ocean Drilling Program. Recent work on the Goban Spur continental margin southwest of the UK suggests that a similar process may have taken place there.
already established elsewhere, mantle rocks were exhumed to the seafloor at the time of continental breakup. In 2003, with Prof. R. B. Whitmarsh (NOCS), Dr J. Collier (Imperial), Prof. M. Kendall (Leeds), I led a detailed seismic study of the conjugate Laxmi Ridge and Seychelles rifted margins in the northwest Indian Ocean. Here, breakup closely followed the formation of the Deccan igneous province and was followed by much faster seafloor spreading than at well-studied margins in the North Atlantic. In 2005 I led a wide-angle seismic study of the Black Sea, in collaboration with Dr N. White (Cambridge), Dr Rose Edwards (NOCS), BP and Turkish Petroleum. The experiment involved both onshore and offshore components. The data from this experiment, combined with extensive deep reflection and borehole data available through our industry collaborators, will allow us to determine both crustal and lithospheric stretching factors and hence whether stretching varies significantly with depth.
Methane hydrate is an ice-like substance that forms in deep water off continental margins and hydrate formation and dissociation may have an important role in global methane budgets. I have worked for many years on the seismic characterisation of gas hydrate provinces all over the world. Most recently, with Dr S. Chand (now at NGU) I have worked on the effect of the presence of hydrate on seismic velocity and attenuation in ocean bottom sediments. My NERC Margins-funded student M. Ellis taking this work further by developing techniques for combined modelling of seismic velocity and electrical resistivity data from marine sediments. Methane sometimes escapes to the seafloor through “pockmark” structures underlain by zones of poor reflectivity in seismic data. In June 2006, with Prof. G. Westbrook (Birmingham) and Dr H. Nouze (IFREMER), I led a high-resolution wide-angle seismic experiment focused on two such pockmarks that forms part of the EU-funded HERMES project.
I led a major initiative involving the universities of Southampton and Durham and Imperial College to set up the UK Ocean Bottom Instrumentation Consortium (www.obs.ac.uk) which operates instrumentation for controlled source seismology, local earthquake and electromagnetic recording on the seafloor. The instrumentation was delivered in 2003 and has supported four major science programs to date. The consortium is now chaired by Dr C. Peirce (Durham).
Links to Active Research
Research on the deep structure of the Eastern Black Sea Basin
