Geophysics, Geodynamics and Tectonics.
Nigel Woodcock is accepting applications for PhD students.
Nigel Woodcock is available for consultancy.
Continental Tectonics - From Fault Breccias to Collision Zones
Charting how and why the continents deform is fundamental to understanding the Earth. The geometries of deformation structures strongly influence where petroleum is stored in the Earth and where mineral deposits form. Traditional field-based observation of these structures remains invaluable in evolving new ideas and testing existing hypotheses. Field observation scales from centimetres to kilometres can be extended downwards by lab-based microscopy and upwards by regional comparisons. Examples of recent projects on three different scales are given below
- Reassessment of the timing and field relations of the Acadian deformation, 400 million years ago, usually attributed to the closure of the Iapetus Ocean between England and Scotland. We have shown that this deformation post-dates closure by 20 million years, and that the intervening period was dominated not by crustal shortening but by crustal extension, sedimentation and magma production.
- Reconstruction of the fault geometry and kinematics along the Dent Fault Zone in northwest England. This fault zone underwent both vertical and lateral slip about 300 million years ago. The way in which these displacements are partitioned between different faults in the zone provides an instructive model for fault zones in general
- Reinterpretation of fault breccias along the Dent Fault. New results show how these breccias created zones of high permeability along the fault, but how this permeability was rapidly sealed by carbonate cements. These results have important implications for the role of faults in petroleum and mineralization systems.
The description and diagnosis of fault breccias forms an exciting research direction for the future. Structural and petrographic techniques will be newly integrated (together with colleague Tony Dickson) to enhance understanding of this poorly understood but economically crucial phenomenon.
Older Publications by Dr Nigel Woodcock