The members of the Staffelegg Formation are correlatable between all boreholes (Fig. 4‑23). Some lateral facies changes occur, but in general the different facies can be identified in all boreholes. In relation to other Mesozoic formations, thickness variations of the different members are small.

Fig. 4‑25:Outcrop of the Staffelegg Formation in the Frick Gruhalde clay pit

The Beggingen Member forms a few-metre-thick limestone succession between the clay-mineral-rich Schambelen and Frick Members. The red arrow denotes a normal fault, which displaces the Beggingen Member (see Section 5.5.4 and Fig. 5‑36 for further information). Modified after Nagra (2014b).