Fig. 6
Working basis section (unbalanced) across the Chasseral crest, illustrating constructed field-constrained horizons and interpreted deep structures that suggest a large-scale fault-bend fold. Wells are projected horizontally into the section plane; therefore the real depth of horizons at the section may deviate. Wells in the Vallon de St-Imier are from Della Valle et al. (1998), whereas wells projected into the Plateau de Diesse are from the Amt für Wasser und Abfall (AWA) Bern. The base excess-area line (BEA-line) was used to estimate the tectonic uplift. Interpolated depth-grids (Engler and Sommaruga 2013) indicate the presumed ramp of the fault-bend fold. Important heights above the basal décollement are indicated on the right hand side. h 1–5 heights of field-constrained horizons, h u height of upper detachment, h 0 basal décollement. Field-constrained horizons are TCr top Cretaceous, TPo top Portlandian, TKi top Kimmeridgian, TSe top Séquanien and TDo top Dogger. Additional horizons indicated by depth-grids are TLi top Liassic, TMuka top Muschelkalk, BMes base Mesozoic