Clavel et al. (2010b) identify six-third order
sequences (one pars: top, four full, one pars:
bottom): Ha2 to Ha6, all of Hauterivian age
(Clavel et al., 2007). This dating is based on the
biostratigraphy of orbitolinids and other fossil
groups. The final sequence of the Hauterivian
(–Barremian transition) is absent and Barremian
or later sequences were not identified in the area.
In a neighbouring section, La Lance, 28 km to the
north-east, Lower Aptian marls cap Hauterivian
strata and infill palaeokarstic cavities (Charollais
et al., 1998). This feature suggests that a major
discontinuity exists above the succession
exposed at Ecle´pens and that the hiatus there
spans a huge interval of time equivalent at least to
the whole Barremian and the earliest Aptian