Page 304 - Carbonate Platforms Facies, Sequences, and Evolution

282
150 m.
�� Black
� Urgonian
shales
wifh
sedimentary sector in Itxina
limesfones
wifh
Mendiola & Garcia-Mondejar (1983).
cal ca reous

Fig. 36. Western platform margin of the Gorbea
breccias
reef-mounds
J.
limestone tongue. Horizontal beds in the background
and the estimated original relief of the clinoforms is =
(sequence U3). Foreslope
clinoforms are seen in the foreground down lapping on to a
correspond to the reef crest. The height of the cliff is 328 m
the
filled
vious
basin,
Garcia-Monde jar
covered
the
practically
in
region,
'Valmaseda
clastic
Bilbao
carbonate
limestones rebuilt
Delta'
wedge
localized
(Fernandez-Mendiola,
Basin.
disappeared
(Rat,
stage
platform
places
in
1986)
1959;
and
and
(Fig.
the
and
reduced in the Aralar (Floquet &
transgressive marls were
was
12).
In the eastern
basin
Pujalte
Rat,
followed
&
Gorbea
Fig. 35. Aramotz-Aranguio palaeogeographic high, corresponding to the Gorbea sedimentary sector. Example of a
Guernica (Agirrezabala et al. , in press.) sectors.
carbonate bank from the sequence U3 with rectilinear, high-gradient outer margins and mud mounds. From Fernandez­
Subsequently, platform carbonate deposition re­
both basinal and platform areas, following the pre­
the suc­
deposited on
deposition
1975) and
part of the
Monge,
significantly
as lowstand deposits since a contemporaneous local
were formed in the west of the region (Ramales and
Bilabo sectors) (Figs 12 & 24). They are interpreted
angular unconformity has been identified in the Ebro
sector (Fig. 22). In the centre of the basin, the big
1985) prograded towards the northwest and partially
and grew vertically (Figs 12 & 24). These processes
the platform to its former limit
ceeding relative sea-level rise. In the western part of
sector
Prograding .