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Post-Doctoral Research Fellow in Geophysics The Post-Doctoral Research Fellow (PDRF) will work under the direction of Prof. Tim Minshull at the National Oceanography Centre Southampton (NOCS). He/she will be employed to work on a NERC-funded research grant entitled “Continental extension leading to breakup: determining the 3D structure of the west Galicia rifted margin”. The position is funded for up to three years ending no later than 31st July 2016. Research Environment The research fellow will work alongside a large group of marine geophysicists in the Geology and Geophysics research group. The group is involved in a wide range of research programs funded by national, European and international funding agencies and industrial partners, and is equipped with an extensive range of marine geophysical equipment. He/she will also have extensive interactions with project partners at the University of Birmingham (Prof. Tim Reston), Rice University (Prof. Dale Sawyer and Dr Julia Morgan), Lamont Doherty Earth Observatory (Dr Donna Shillington), and GEOMAR (Dr Dirk Klaeschen). Research Facilities The geophysics group at NOCS has extensive computing facilities including a dedicated geophysics group Linux cluster. For seismic data processing we have 2D and 3D Promax, and for interpretation we have Petrel. The National Oceanographic Library is located within the building, and most journals relevant to the project are available electronically through the library. The project will make use of the UK’s national pool of ocean bottom seismometers, which is operated by the UK Ocean Bottom Instrumentation Consortium at Southampton and Durham. Project Description The project is a collaborative effort between the Universities of Southampton and Birmingham in the UK, Rice University and Lamont-Doherty Earth Observatory in the US, and GEOMAR in Germany. The overall aim of this international project is to provide new insights into the process of continental breakup by acquiring a unique new three-dimensional seismic dataset on the west Iberia rifted margin. Data acquisition will take place during May to September 2013 and will involve a 45-day cruise of the US vessel R/V Marcus Langseth in June-July 2013 preceded by deployment of 78 ocean bottom seismometers (OBSs) from the UK and Germany during late May to early June and followed by recovery of these instruments in August-September. OBS operations will be conducted from the German vessel Poseidon. A fully three-dimensional seismic reflection volume will be acquired, augmented by some longer 2D lines, and all shots will be recorded on a grid of OBSs. The experiment will focus on the rifted margin west of Galicia Bank in a region where the so-called “S-reflector” marks a large-scale low-angle detachment that was active during the later stages of continental breakup. The analysis of this dataset will allow the following specific objectives to be met: 1. Measure the degree, direction and mechanism of brittle extension and its variation in space and time over a c. 15000 cubic km volume of lithosphere. Key questions include the timing, duration and rates of fault growth, fault linkage and other interactions, the importance of sub-seismic faulting, interaction of faults with S, evidence for multiple phases of faulting; 2. Determine the relationship between subsidence patterns, lateral fault propagation and linkage of faults, and the pattern of strain localisation 3. Measure the physical properties of the fault zone defined by S and those of the underlying mantle, and relate variations in these properties to the 4. 5. 6. behaviour of the fault over time. Determine the relationship between the intensity of faulting of the crust overlying S and the degree of serpentinisation of the mantle beneath S. Generate a full 3D reconstruction of the development of a c. 25x55 km segment of margin over time. Determine optimum sites for future IODP drilling to provide detailed timing constraints on margin evolution and hence rates of the processes involved. The project builds on extensive previous work on the west Iberia margin and its conjugate by Minshull, Reston, Sawyer, Shillington and Klaeschen. Role of the Research Fellow The project will involve a large team of scientists. The specific role of the NOCS PDRA will be to take charge of the tomographic analysis of the three-dimensional OBS dataset, including: 1. Participation in at least one of the three cruises in summer 2013. 2. Application of novel processing methods to the densely-sampled threedimensional OBS dataset. 3. Travel-time tomographic inversion of a subset of the full 3D dataset. 4. Integration of wide-angle seismic models with coincident reflection data (existing or newly acquired as part of the project) and other geophysical constraints. 5. Interpretation of models in terms of lithologies, degree of serpentinisation, etc. 6. Supporting and collaborating with other consortium members working on different aspects of the OBS dataset for different purposes. 7. Presentation of results at international conferences and timely publication in top international journals. Skills Required Applicants should have a strong educational background in geophysics. A strong mathematical and computing background is desirable, as is experience of analysing large datasets in a Unix environment. Experience of wide-angle and/or deep crustal seismic data analysis is also desirable, though not essential. The successful candidate will have good written and verbal communication skills.