Continental Margin Process Analysis, Structures & Stratigraphy
Global synoptic survey of the breakup unconformity and its links to volcanism and post-rift sedimentation
Supervisors: Prof J Morgan, Dr M Perez-Gussinye, Prof P Burgess
At rifted margins, a ‘breakup unconformity’ is frequently found between the transition from syn-rift to post-rift sediments. Here we propose to examine globally distributed 2-D seismic profiles to make time-space maps of the global patterns of breakup unconformities at rifted margins, and their relationships to other margin patterns such as whether the margin was a volcanic or non-volcanic rifted margin, whether there was noticeable post-rift deformation, and whether and how post-rift deposition migrated with respect to syn-rift deposition.
Using this atlas of global patterns, the student will then examine how the Arctic-, North- and South Atlantic basins differ in their appearance and development of the breakup unconformity from other margins. We will also explore what volcano-tectonic mechanisms are responsible for the formation of a breakup unconformity using in-house codes for 2-D visco-elastic-plastic rift deformation and volcanism that incorporate regional pattern of erosion and sediment transport. We will also explore the effects of a possible phase of post-rift deformation in these models to assess this effect on the development of margin structures.
Specific deliverables of PhD project 5 are:
- A literature review of breakup unconformity examples, with initial assessment of the proposed mechanisms.
- Description and interpretation of correlations between global patterns and correlations of the breakup unconformity with other margin characteristics (such as the presence or absence of seaward-dipping reflectors and the presence or absence of post-rift margin deformation).
- Systematic comparison of observed global B/U patterns with 2-D numerical models for the development of volcanic/non-volcanic rifted margins.
- Review of breakup unconformity examples, with explanation and critical assessment of the proposed mechanisms.
- Global B/U survey and synthesis will also be made available as a ‘digital atlas’ of maps and correlations as part of the COMPASS deliverables.