Seismic interpretation and gravity modelling of BIRPS SWAT lines 5 and 6

Seismic interpretation of the British Institutes Reflection Profiling
Syndicate (BIRPS) seismic reflection lines SWAT 5 and 6 was carried out
and a time section showing the major reflective horizons drawn up. This
section was depth converted and where possible geological ages given to
the sedimentary reflectors and densities assigned to the geological
bodies. Using a computer gravity modelling program the theoretical and
observed gravity anomalies were compared and some slight modifications
were made to the models to enhance agreement between the two.
The models indicate that the lower crust may have a higher density in the
north, suggesting that there may be a boundary between two crustal blocks
at the north end of the SWAT 6 profile. It is also tentatively suggested
that the Haig Fras batholith was injected from below whereas the Cornubian
Batholith may have been intruded from the south.