BhFwas drilled on top of the esker ridge; the top 4 mare dominated
by muddy sandy gravel with silty sandy matrix, no recovery from 4 to
10m and gravelly mud from 10 to 11.5 m. The borehole logs and sample
descriptions based on Folk (1954) classification scheme are presented
in Fig. 3; the layers recorded for each borehole log are
generalised to the dominant lithology.