Geology Reference
In-Depth Information
Fig. 18.18
(
a
) Overview of the tidal bundle outcrop locality
along the Isábena River. The tidal bundles are located in the
lowermost 5 m of the cliff section as indicated by the box.
(
b
-
e
) Details of the tidal bundles showing the mud draped
foreset and bottomset laminae. Paleofl ow from
left
to
right
(SE to NW)
Bay' (Eichenseer
1988
). The Roda Sandstone Gilbert-
type delta lobes debouched into this embayment.
The uncommon occurrence of a tidal bundle suc-
cession of approximately 10 m long (Fig.
18.16e
) in
the Baronia Fm near the village of La Règula
(Fig.
18.11
) in an erosional depression on the seafl oor
is interpreted to be either associated with an estuarine
channel and shoal (cf. Mutti et al.
1985b
) or a large
tidal scour fi lled by a forward accreting compound
tidal dune (cf. Olariu et al.
2008a,
b
) . Given the paleo-
geographic setting of the Baronia Fm, the latter inter-
pretation is considered more likely.
Sigmoidal and bidirectional cross-stratifi ed beds
with double mud-draped toesets and tidal bundles as
well as herringbone cross-bedding and reactivation
surfaces occur in sandstone bodes 4 and 5 of the
Pallaresa member of the Ametlla Fm (Dreyer
1994
) .
Large-scale sigmoidal cross-stratifi ed sets of up to
5 m thick contain tidal bundles with well-developed
double mud drapes, mostly in the toesets, and reacti-
vation surfaces (Fig.
18.15c-f
). Average foreset dip
angle is 23° to the NW interpreted to have been
formed by the ebb-dominant currents (Dreyer and
Fält
1993
) .
