Geoscience Reference
In-Depth Information
Fig. 5. The 1174 m Ichthyostega locality from Sederholm Bjerg, Paralleldal. (a) Profile Ravine showing formations
and location of 1174 m Ichthyostega locality. (b) Close-up of 1174 m locality showing residual blocks of sandstone left
by earlier expeditions. Henning Blom for scale. (c) Vertisol fracture surface from Britta Dal Formation showing
brecciation caused by expansion and contraction cycles. (d) Red-green (dark-pale) vertisol cycle from Profile Ravine.
Thin sandstone stringers (immediately above and below field notebook) occur within the green-coloured silts, indicating
these to be the relatively wetter units. (e) Part of Britta Dal Formation section measured from Parallel Ravine showing
vertisol cyclicity. These vertisol cycles together with the sandstones are the 'banks' used for correlation by Johansson
(Jarvik) 1935 and S
¨
ve-S
¨
derbergh (m/s cited in Blom et al. 2005).
