Page 128 - Carbonate Platforms Facies, Sequences, and Evolution

1984;
iron ore.
immature
SE
Galien,
characteristics
and
grainstones; 11 =
lowest Liassic beds
even
1985).
have
in
kept
Hms
the
their
and morphoscopic studies (Taibi,
Si
Hms
spicules (sponges); 12 =
marine
fluvial
SO
or
to S3b
(mainly Hettangian) are wide­
sandstones, and of carbonate pebbles sourced from
1984; Elmi et at. ,
cephalopods; 9 = nodular limestones with cephalopods; a-
spread along the Ardeche margin. Carbonate matrix
as well as bioclasts are genetically independent of
and quartzite pebbles, reworked from the Triassic
environment
transport, as evidenced by calcimetric, granulometric
the coarse clastic material, especially in regard to
Quartz grains or pebbles are
littoral
S 5.TOARCIAN
the
but
marly, b-
age.
more
slopes
example,
owing
initial
the
to
extending
the
fluvial
Late Triassic and Jurassic platforms, France
coarsest
from
to AA LENIAN {pars)
HETTANGIAN- SINEMURIAN
and
general
commonly related to
stromatolites; 13 = erosion; 14 = slumps and slides; 15 =
more
emergent
3
14
a
granulometric
13
or
environment,
15 \illilll\11
! >-SI
4 1L I\ I
1 - 1
12�
s!�-.
1oiT]
11[TI
1E
s!'m!
�
I::±.::::?!
very
1�
ENE
immature
9��
the existence of
swells, to more-or-less narrow, deep, basins
pattern.
detrital limestones; 6 = coarse, terrigenous clastics and conglomerates; 7 = marls; 8 = nodular limestones without
mostly calcareous; 10 = Isocrinus breccias and
they
Fig. 7. Palinspastic profiles along the Ardeche Margin of the Subalpine Basin from the early Liassic to the early Bathonian.
material has been found in micritic laminated lime­
1 = fine-grained micrites; 2 = skeletal limestones; 3 = oolitic limestones; 4 = sandy and quartzitic limestones; 5 = coarsely
ferruginous beds and
117
stones interbedded in black shales of early Toarcian
Some of these influxes can be storm-related,
are
quartz
where they have been buried. Marine transportation
has been fast and short without any modification of
For
(here
shallow
steep