OR/16/004 Modelled faults

Barron, A J M. 2016. GSI3D model metadata report for HS2 Area 3 (Newton Purcell to Thorpe Mandeville). British Geological Survey Internal Report, OR/16/004.

Several small faults, most with throws of less than 10 m were modelled as fault plane objects, dipping 60 degrees for drawing guidance, based on mapped surface faults (Figure 11) but were subsequently removed (see model Development Log, 15/5/13; 14/6/13; 10/3/14) as they were hindering calculation. Faults were modelled using the superficial engine as steps in the geological surfaces (rather than as a faulted bedrock model) where the unit is in contact across the fault. However, where unit envelopes intersected faults at depth and were present on both sides, but fault throw exceeds unit thickness, slits in envelopes were drawn to aid calculation. No major faults occur in the modelled area.