Lithospheric structure north of Scothland--I. P-wave modelling deep reflection profiles and gravity

Abstract

The W-reflector and the Flannan reflector are two enigmatic planar structures in the lithospheric mantle north of Scotland, mapped in three dimensions using deep reflection profiling. The Flannan reflector dips eastwards from the Moho to a depth of 80 km at an angle of 0°, whilst the W-reflector is subhorizontal, lying 10-20 km beneath the Moho and terminating westwards against the Flannan. Both reflectors have a strong impedance contrast and are laterally coherent over tens of kilometres. Wide-angle seismic reflection and refraction data are used here to constrain the P-wave velocity structure of the lithosphere in this region and to investigate the physical properties and geometry of these reflective structures.