Page 211 - Carbonate Platforms Facies, Sequences, and Evolution

0
Ql
A
to
5
s
4
2
� 3
1981;
I
I
about
210
1982),
the
corded
(1981).
(Jansa,
sectional
E
Portugal.
American
the
'0'
number
O r- -
Ellis,
The
were
I
--
from
of
1981),
M
180
this
1984:
marker
C
for
Atlantic
JURASSIC
geometries
0
lithological
carbonate
�
K
- � \ - ,
carbonate
both
T
150
and
Fault-controlled
I
although
located over a
margin
\ \ � ·-
Canadian
ramp
compacted burial
.�
_
decompacted burial
content
..••• I paleo) water depth
Buildup geometries and settings
\ �
units
carbonate of
Age IMal
buildups
=
E
have
shelves
of the
settings
120
and
the
variation of the Portuguese buildups.
breccias
�
overly
from
to
example),
=
Mem
were
I
Shell Penobscot L-30 on the Scotian Shelf
similar
Grand
lateral
the
=
90
while
CRET ACEOUS
not
analogous
those
L
AAeeEIAO
formation displays similar lithofacies and cross-sec­
cross­
re­
rapidly subsiding con­
(Eliuk,
tional geometry to sequences cored by Petro-Canada
to
the
to represent the main 'reef trend' (Schlee & Grow,
North
in
tinental margin and facing the newly-opening ocean.
from the Grand Banks Le Have platform by Jansa
Montejunto and Ota, for example, were identified
Martins
facies
slope sediments. The majority of the eastern North
American Upper Jurassic buildups and those taken
prograding
Though this represents a very different setting from
Banks
Amaral Formation has a similar stratigraphic setting
' �- ----------
:5
estimated from sedimentological and palaeoecological studies.
E
0
�
Ql
a.
��
5
4
3
2
11
sw
o
400]
m""et
NW
O +"' ""re-=-
s -
180
--,
•o ' oo
Upper Jurassic carbonate buildups, Portugal
( Eliuk, 1978)
·oEMASCOTA
MONTEJUNTO
�SE
150
------.J BARREIRO
BALTIMORE CANYON
then into presumed slope deposits.
Age (Mal
(Meyer,19 89l
120
W
& 111·············
..-
E
orA
90
CRET ACEOUS
Fig. 23. Comparative cross-sectional geometries of
level, and above the Lourinha formation using thicknesses from nearby measured sections. Palaeowater depths were
NE
north west, which pass basinwards into carbonates and
Canyon example comprises siliciclastic sediments to the
or penetrated by wells. The white area in the Baltimore
Fig. 22. Burial histories for the Barreiro and Ramalhal areas. That for Barreiro was computed from well data from Barreiro
197
#1, but the well data for Ramalhal was augmented using seismic data below the Upper Jurassic down to the top-Dagorda
speculative extensions of the buildings not seen at outcrop
Portuguese and North American buildups discussed in the
text. The white areas in the Portuguese examples represent