THE OLIGOCENE-MIOCENE GHOMARIDE NAPPE COVER (INTERNAL RIF, MOROCCO) 93
THE OLIGOCENE-MIOCENE GHOMARIDE COVER:
A PETRO-SEDIMENTARY RECORD OF AN EARLY SUBSIDENT
STAGE RELATED TO THE ALBORAN SEA RIFTING
(NORTHERN INTERNAL RIF, MOROCCO)
MOHAMED NAJIB ZAGHLOUL
1
, LISA GIOCONDA GIGLIUTO
2
, DIEGO PUGLISI
2
*,
ABDELOUAHED OUAZANI-TOUHAMI
3
and ABDERRAHIM BELKAID
4
1
Département des Sciences de la Terre et dOcéanologie, Université Abdelmalek Essaadi, Faculté des Sciences et Techniques, Tanger,
Maroc; zaghloul@fstt.ac.ma
2
Dipartimento di Scienze Geologiche, Università di Catania, Italy; dpuglisi@mbox.unict.it
3
Département de Géologie, Université Abdelmalek Essaadi, Faculté des Sciences, Tetouan, Maroc; aouazani@fst.ac.ma
4
Département de Recherches Géologique et Géotechnique GEORET s.a.r.l., Tanger, Maroc; abelkaid1999@yahoo.fr
(Manuscript received May 22, 2002; accepted in revised form December 12, 2002)
Abstract: New sedimentological, petrographic and structural data have been collected from the Oligocene-Miocene
terrigenous deposits unconformably overlying the highest tectonic units of the Internal Rifian Chain (Ghomaride Units).
These new data show (i) the abundance of coarse-grained facies (disorganized and organized conglomerates and pebbly
sandstones), (ii) a sedimentary supply from very slightly metamorphic Paleozoic sources and from Mesozoic carbonate
cover and (iii) the dominance of a mainly extensional syn-sedimentary tectonic activity. Stratigraphic and petrographic
characters point out a paleogeographical scenario where the Ghomaride Units, believed to be the sources of the analysed
successions, fed small satellite basins located above the fold-thrust belt by means of gravity and debris flow processes.
Moreover, the low textural maturity of the analysed sandstones seems to suggest conditions of short transports linked to
a rugged topography and to a very unstable tectonic setting. Structural data acquired, in good agreement with that of
literature, confirm the existence of a mainly extensional tectonic activity which lasted from the Late Oligocene up to
Middle Burdigalian times during the deposition of the analysed successions. So, within a mainly extensional geodynamic
context, a continuous rapid erosion of the highly elevated parts (mainly Ghomaride Units) of the folded thrust belt,
progressively uplifted, produced the sedimentary supply. During this Late OligoceneLower Miocene rifting stage,
some of these satellite basins evolved, in the rear of the Rifian fold-thrust belt, to more subsiding areas as continental
trenchs and triggered the opening of the Alboran Sea.
Key words: Morocco, Rif Mediterranean belts, Oligocene-Miocene rifting, sedimentary petrography, turbidite sandstone
suites.
Introduction, geological setting and objectives
The internal zones of the Betic Cordillera (Spain) and of the
Rif (Morocco) are geologically homologous (Didon et al.
1973; Durand-Delga & Olivier 1988) and characterized by the
superimposition of several basement nappes, belonging to the
Alboran terrane (Chalouan et al. 2001; Michard et al. 2002),
locally with remnants of their original Mesozoic-Cenozoic
sedimentary cover. In the Rifian Chain these are commonly
regrouped into the Ghomaride, Sebtide and Dorsale Cal-
caire Units (structurally from top to bottom), the latter rep-
resenting remnants of a Mesozoic carbonate platform evolv-
ing into terrigenous deposits during EoceneOligocene times
(Wildi 1983).
The Ghomaride nappes (Fig. 1), the highest tectonic ele-
ments, mainly consist of slightly metamorphic Paleozoic suc-
cessions (Durand-Delga & Kornprobst 1963; Kornprobst
1974; Chalouan 1986), organized into four tectonic units
(from the base to the top: Aâkaïli, Koudiat-Tizian, Beni-
Hozmar and Talembote Unit; Chalouan 1986; Azzouz 1992),
the total thickness of which does not exceed 5000 m (Chal-
ouan & Michard 1990). Each of these Ghomaride Units has its
unconformable Mesozoic-Cenozoic sedimentary cover (Du-
rand-Delga et al. 1964; Belhadad 1983; Maate 1984; Bouhda-
di 1985; Chalouan 1986; Feinberg et al. 1990; Ouazani-Tou-
hami 1994), which could be considered as a lateral equivalent
of the so-called Dorsale Calcaire Units (Wildi 1983; Maate
1996, with references), detached from the uppermost Sebtide
Units and piled up in front of the Ghomaride realm. The Me-
sozoic portion of this succession (Middle Triassic reddish
quartzose sandstones and conglomerates, Upper Triassic dolo-
mites, Liassic limestones and reddish silts; Maate 1984) can
be related to the Tethyan rifting processes. In contrast, the
younger deposits (Microcodium and Nummulitic limestones
and mainly calcareous conglomerates; Maate 1984, 1996;
Maate et al. 1991; Ouazani-Touhami 1994), aged to Late
Eocene (Olivier 1979; Olivier et al. 1979), could represent a
depositional sequence post-dating an early Alpine compres-
sive event (Martin-Algarra et al. 2000).
Some of the Ghomaride Units, at the top, are transgressively
and unconformably covered and sealed (Durand-Delga 1980;
Feinberg et al. 1990; Maate et al. 1995; Martin-Algarra et al.
2000) by Oligocene-Miocene successions (Chattian to lower
Burdigalian; Belhadad 1983; Feinberg & Olivier 1983; Maate
GEOLOGICA CARPATHICA, 54, 2, BRATISLAVA, APRIL 2003
93105
*Corresponding Author: Tel.: 0039-095-7195724 ; Fax: 0039-095-7195728; dpuglisi@mbox.unict.it
94 ZAGHLOUL et al.
1984; Martin-Algarra 1987; Feinberg et al. 1990; Maate et al.
1995). These Ghomaride nappe covers, the object of this
study, display sandstones, marls, and carbonatoclastic depos-
its organized in thick conglomeratic bodies with presence of
metric olistoliths. These successions, well known also in the
Betic Cordillera where they unconformably overlie the
Malaguide Units (equivalent to the Ghomaride Units), have
formally been subdivided into two successive sedimentary cy-
cles (Chalouan 1987; Martin-Algarra 1987; Maate 1996): the
earlier (Upper Oligocene up to the Oligocene-Miocene bound-
ary) is related to the Ciudad Granada (Betics) and Fnideq (Rif)
Formations, while the latest, referred to as the Viñuela (Betics)
and Sidi Abdesslam (Rif) Formations, is dated as Early Mi-
ocene (mainly Lower Burdigalian). This second sedimentary
cycle is well known all along the Maghrebian Chain (Guerrera
et al. 1993), being in good agreement with the tectono-sedi-
mentary evolution of the internal domains of the Kabylides
(Algeria, Oligo-Miocene Kabyle; Tefiani 1970; Raymond
1976; Gelard 1979; Géry et al. 1981) and of the Calabria-
Peloritani Arc (Sicily, Stilo-Capo dOrlando Formation; Og-
niben 1973; Puglisi 1987; Patterson et al. 1995; Bonardi et al.
1996; Cavazza et al. 1997).
In this paper, we point out new petrographic and sedimento-
logic data about some Oligocene-Miocene deposits of the
Ghomaride nappe cover (Fnideq and Sidi Abdesslam Forma-
tions). In agreement with previous works (Chalouan 1986;
Chalouan et al. 2001) we show that these deposits can be ten-
tatively related to the Late Oligocene rifting phase which
widely affected the western Mediterranean region, as a pre-
lude to the Miocene opening of new oceanic areas (i.e. the Al-
gero-Provençal Basin Auct.).
Sedimentology and lithostratigraphy
Four stratigraphic sections of the Oligocene-Miocene de-
posits of the Ghomaride nappe cover, unconformably sealing
several Ghomaride Units in the Rif Chain, as above men-
tioned, were measured and sampled: the Kellaliyine and Beni
Maâdane Sections, representative of the Ciudad Granada-
Fnideq Formation Cycle, and the Sidi Abdesslam and Boujar-
rah Sections, representative of the Viñuela-Sidi Abdesslam
Formation Cycle
1
.
Ciudad GranadaFnideq Formations
The Ciudad GranadaFnideq Formations (Upper Oligocene
up to the Oligocene-Miocene boundary, Zone NP25 of Marti-
ni 1971, in Feinberg et al. 1990; Maate 1996 and bibliography
therein) regroup the syn-orogenic conglomeratic-arenaceous-
pelitic successions, which unconformably overlay the
MalaguideGhomaride nappes and their Mesozoic cover
(Martin-Algarra 1987; Guerrera et al. 1997).
In the Rifian sector this cycle can be subdivided into two
mainly conglomeratic intervals:
1. A lower siliciclastic conglomeratic interval (east and
north-east of Tetouan), directly overlying the Paleozoic base-
ment and/or its Mesozoic carbonate cover. In the Beni
Maâdane area and also in the Kellaliyine quarry, this interval
stratigraphically rests on an arenaceous-pelitic lithofacies,
about 4 m thick (Fig. 2). The sedimentological character of
this conglomeratic interval suggests processes such as debris
Fig. 1. Geological sketch map of the internal zones of the Rifian
Chain (Morocco).
Fig. 2. Simplified stratigraphic section of the Kellaliyine outcrop
(Upper OligoceneAquitanian?; Internal Rif, Morocco). 1 aren-
aceous lithofacies; 2 pelitic lithofacies; 3 grain size in
ϕ
scale; 4 location of the analysed samples; 5 and 6 positive
and negative cycles, respectively.
1
Kellaliyine Section (lat 35°3613 N and long 5°2039 W), Beni Maâdane Section (lat 35°3420 N and long 2°1730 W), Sidi Abdesslam
Section (lat 35°3513 N and long 5°1556 W), Boujarrah Section (lat 35°3601 N and long 5°2119 W).
THE OLIGOCENE-MIOCENE GHOMARIDE NAPPE COVER (INTERNAL RIF, MOROCCO) 95
flows and/or as highly concentrated turbidity currents with
traction transport as bed-load, which can be related to those of
the disorganized and organized conglomerates (facies
A
1.1
and A
2.1
of Pickering et al. 1989).
2. An upper mainly calcareous conglomeratic and arena-
ceous interval, about 150 m thick (Beni Maâdane Section,
Figs. 3 and 4), made up of matrix and clast-supported orga-
nized and disorganized conglomerates, displaying a thinning-
and fining-upward trend and also characterized by the occur-
rence of plurimetric calcareous and arenaceous olistoliths and
of the following lithofacies:
organized and disorganized pebbly sandstones, made up by
sandstone bodies up to 6 m thick, with repetitive normal
and/or inverse graded sequences and with clay chip hori-
zons, interpreted as the sedimentary result of high concen-
tration turbidity currents or as the mass deposition from hy-
perconcentrated flows of a pebbly-sandy mixture (facies A
2
and A
1.4
of Pickering et al. 1989).
stratified sandstones and gravelly sandstones, represented
by medium- to very coarse-grained sandstone beds, up to
1 m in thickness, with crude lamination and normal or re-
verse grading, resulting from multiple traction carpets under
high density turbidity current conditions (facies F
4
and B
2.1
,
according to Mutti 1992 and to Pickering et al. 1989, re-
spectively).
classical turbidites, characterized by medium- to coarse-
grained graded sandstones with complete or incomplete
Bouma sequences, derived from unstable high density tur-
bidity currents (facies F
7
-F
8
-F
9a
of Mutti 1992 and facies
C
2
of Pickering et al. 1989).
These two conglomeratic intervals are separated by yellow-
ish-brownish massive clays (about 190 m thick, Fig. 4) with
thin-bedded and fine-grained reddish turbidites, the thickness
of which increases upward.
ViñuelaSidi Abdesslam Formations
In the Internal Rif this second sedimentary cycle consists of
an Early to Middle Burdigalian depositional sequence (N56
of Blow 1969, in Maate 1996), known as Sidi Abdesslam For-
Fig. 3. Geological sketch map of the Beni Maâdane area (Internal Rif, Morocco) showing the mainly conglomeratic Oligocene-Miocene
deposits of the Ghomaride nappe covers. 1 Pliocene and Quaternary deposits; Oligocene-Miocene deposits of the Ghomaride nappe
cover: Upper Conglomeratic Interval: 2 calcareous conglomerates, 3 mixed conglomeratic lithofacies (siliciclastic and calcare-
ous), 4 siliciclastic conglomerates; Lower Conglomeratic Interval: 5 marls, 6 siliciclastic conglomerates; 7 limestones and
dolostones (Upper Triassic to Lower Lias); 8 Verrucano-like red clays, sandstones and conglomerates (Triassic); 9 Paleozoic base-
ment of the Ghomaride Units: (a) Beni Hozmar and (b) Aâkaïli nappes; 10 nappe stacking contacts; 11 low angle normal faults;
12 high angle normal fault; 13 strike-slip faults.
96 ZAGHLOUL et al.
mation, unconformably overlying the Ghomaride and the
Sebtide Units (Chalouan 1987; Maate 1996).
The Sidi Abdesslam Section (Fig. 5; Martin-Algarra 1987;
Ouazani-Touhami & Chalouan 1995), begins with an arena-
ceous-pelitic lithofacies, marked by yellowish-reddish coarse-
grained sandstones at the bottom (about 8.5 m thick) and
grading upward to yellowish marls with fine-grained and thin-
bedded turbidites. Successively, after about 200 m of unex-
posed section, the Sidi Abdesslam Formation shows a con-
glomerate interval made up by disorganized and organized
breccias and conglomerates (24 m thick) with angular to sub-
angular Paleozoic pebbles floating into an abundant fine-
grained sandy matrix. These conglomerates are associated
with chaotic facies (e.g. slumps) and, locally, with graded
coarse-grained yellowish-brownish sandstones.
The base of this section has been related to the Fnideq For-
mation (Ouazani-Touhami & Chalouan 1995) and the geomet-
rical relations with the overlying polygenic conglomerates of
the Sidi Abdesslam Formation are marked by a gentle uncon-
formity.
At the top of this conglomeratearenaceous interval the Sidi
Abdesslam Formation continues with yellowish thin-bedded
and fine-grained calcareous turbidites (not more than 2 m
thick) grading upward to mainly pelitic facies (about 20 m
Fig. 4. Simplified stratigraphic section of the Beni Maâdane out-
crop (Upper OligoceneLate Aquitanian; Internal Rif, Morocco).
1a calcareous conglomerates and chaotic facies, 1b arena-
ceous lithofacies, 1c lower siliciclastic conglomeratic interval;
2a pelitic lithofacies, 2b metric olistoliths; 3 convolute
laminations; 4 parallel laminations; 5 mud clasts; 6 and 7
normal and inverse grading, respectively; 8 scouring. For the
other symbols see Fig. 2.
Fig. 5. Simplified stratigraphic section of the Sidi Abdesslam For-
mation (Lower Burdigalian) at the homonymous locality
(Ghomaride nappe cover, Internal Rif, Morocco). 1 conglomer-
ate and breccia lithofacies; 2 gravelly to medium-grained sand-
stones; 3 fine-grained sandstones; 4 thin-bedded calcilu-
tites; 5 silexite levels; 6 marls and pelitic lithofacies. For the
other symbols see Fig. 2.
THE OLIGOCENE-MIOCENE GHOMARIDE NAPPE COVER (INTERNAL RIF, MOROCCO) 97
thick), characterized by rare arenaceous beds and by the occur-
rence of some whitish silexite beds (Maate 1996). These
clays increase in thickness in the Boujarrah Section (up to
100 m, Fig. 6), where silexite levels and amalgamated turbid-
itic sandstone beds, about 2 m thick, have been observed, re-
spectively, at the base and in the middle portion of this section.
Fig. 6. Simplified stratigraphic section of the Sidi Abdesslam For-
mation (Lower Burdigalian) at the Boujarrah outcrop (Ghomaride
nappe cover, Internal Rif, Morocco).
Petrographic characters of the sandstones
Table 1 lists the gross composition of the sandstone levels
characterizing the Ciudad Granada-Fnideq Formation and
Viñuela-Sidi Abdeslam Formation Cycles. The mean values
of the detrital modes known in literature for these formations
(Guerrera et al. 1977; Puglisi et al. 2001) are shown in Table 1
and compared with the new petrographic data here obtained.
In Table 1 are also shown the compositional parameters
adopted for the modal analysis; these have been performed ac-
cording to the criteria suggested by Gazzi (1966), Dickinson
(1970) and by Gazzi et al. (1973), in order to minimize the de-
pendence of rock composition on grain size. The Q
m
, F and
L
t
parameters are also included in this Table, as suggested by
Graham et al. (1976) and by Dickinson & Suczek (1979) as a
means of recognizing the provenance of the clastic supply
(QFL and Q
m
FL
t
parameters, in fact, emphasize the maturity
and provenance of the sandstones, respectively).
In the first cycle eleven sandstone samples have been analy-
sed: four collected from the lower siliciclastic conglomeratic
interval (East and North-East of Tetouan, near the Kellaliyine
village; samples K
1
→
K
4
) and seven from the upper calcare-
ous conglomeratic interval (Beni Maâdane Section; samples
BM
1
→
BM
11
).
On the basis of their composition all the analysed sand-
stones can be referred to the litharenite group. Small differ-
ences, in fact, observed among the two sets of sandstones are
not significant and the framework modes of the studied rocks
as well as their textural characters point to the same prove-
nance and to very similar conditions of sedimentary transport,
usually not prolonged and related to a very rugged topo-
graphy.
Ciudad Granada-Fnideq Formation Cycle
The sandstones of the Fnideq Formation sampled within
both the lower siliciclastic and upper calcareous conglomerat-
ic intervals show a very similar composition. The first ones
(Q
62.1
F
3.2
L
34.7
, Qm
38.8
F
3.2
Lt
58.0
) are characterized by the
abundance of quartz grains and of lithic fragments, with a
very low content of feldspars. The lithic fraction is mainly
represented by quartzites, metasedimentary rocks (quartzose
metarenites and metalimestones), rare phyllites and alterated
volcanic rocks, these last with porphyritic structure, ground-
mass with fluidal texture, and with almost all mineralogical
components poorly preserved.
The sandstones of the Beni Maâdane Section (upper calcar-
eous conglomeratic interval) can also be ascribed to the lith-
arenite family (Q
54.3
F
1.7
L
44.0
, Qm
31.8
F
1.7
Lt
66.5
) showing
abundant fragments of quartzites, semischists, chlorite-
schists, mixed with a few of micritic limestone. Moreover, in
some clast we also observe the biotite as accessory component
of phyllite fragments, testifying to a metamorphic grade of the
source rocks slightly higher than that recognized for the prov-
enance of the Kellaliyine outcrop sandstones. However, for
both successions it is possible to exclude a conspicuous con-
tribution from plutonic and/or high grade metamorphic sourc-
es. The content of feldspars, in fact, is very scarce in spite of
the abundance of quartz and lithic fragments, the latter being
represented by a small amount of volcanic clasts. Further-
more, the sandstones of both the lower siliciclastic and upper
calcareous conglomeratic intervals usually show a low textur-
al maturity (poor sorting, abundance of angular to subangular
quartz grains, presence of a large amount of siliciclastic ma-
trix, often pseudomatrix-like, sensu Dickinson 1970) which
strongly points to very short transports.
A provenance from volcanic sources is supported within
this upper calcareous conglomeratic interval, well exposed in
the Beni Maâdane Section, by the presence of abundant volca-
nic pebbles. The petrographic characters of these volcanic
98 ZAGHLOUL et al.
Table
1:
Modal
point
counts
of
the
analysed
sandstones
of
the
Fnideq—Ci
udad
Granada
and
Sidi
Abdesslam—Vi
ñuela
Formations.
x and
σσσσσ
= mean framework modes and standard deviation; n = number of analysed samples.
1 — Ciudad Granada and V
iñuela Formations (Betic Cordillera), analyses from Guerrera et al
. (1977);
2
— Fnideq
and Sidi Abdesslam Formations (Rif, Morocco), analyses from Puglisi et al. (2001).
Symbols of the parameters adopted for the modal analysis
Q = Q
m
+ Q
p
, where:
Q
=
total quartzose grains,
Q
m
=
monocrystalline quartzose grains (including
Q
r
= quartz in coarse-grained rock fragments, i.e. > 0.06 mm),
Q
p
=
polycrystalline quartzose grains (including
Ch
= chert);
F = P + K
, where:
F
= total feldspar grains,
P
and
K
=
plagioclase and potassium feldspar single grains (
Ps
and
Ks
) or in coarse-grained rock fragments (
Pr
and
Kr
);
L
= Lv + Lc + Lm
, where:
L
= unstable fine-grained rock fragments (< 0.06 mm, i.e.:
Lv
= volcanic,
Lc
= carbonate and
Lm
= epimetamorphic lithic fragments);
Lt = L + Q
p
, where:
Lt
= total lithic fragments (both unstable and quartzose);
M =
micas and/or chlorites, in single grains (
Ms
) or in coarse-grained rock fragments (
Mr
);
Al =
other mineral grains,
Mt
= siliciclastic
matrix;
Cm
= carbonate
cement.
C
iu
d
ad G
ran
ada
-F
ni
d
eq F
orma
ti
on
C
ycl
e
V
iñ
ue
la
-S
id
i A
b
de
ss
la
m F
orm
ati
on
C
ycl
e
L
owe
r si
lic
ic
la
st
ic
c
on
glo
me
ra
tic
in
te
rval
U
p
pe
r
cal
car
eo
us
c
on
gl
omer
ati
c i
nte
rva
l
(B
en
i M
aâdan
e
Sect
io
n)
B
ouj
ar
ra
h S
ec
ti
on
S
id
i A
b
de
ss
la
m
S
ec
ti
on
C
iu
d
ad
G
ran
ada
Form
at
io
n
1
(n
=
6)
Fn
id
eq
Form
at
io
n
2
(n
=
3)
V
iñue
la
Form
at
io
n
1
(n
=
5)
Si
di
A
b
de
ss
la
m
Form
at
io
n
2
(n
=
6)
K
1
K
2
K
3
K
4
BM
1
BM
2
BM
3
BM
4
BM
7
BM
8
BM
11
BJ
1
BJ
2
BJ
3
BJ
4
SD
A
5
SD
A
11
SD
A
15
x
σ
x
σ
x
σ
x
σ
Q
m
22.
6 25.
1 24.
9
26.
8 18.
7 17.
5
19.
1 20.
3 18.
5
21.
2 19.
9 23.
6
25.
0
21.
9 22.
8
31.
1
27.
2
26.
7
12.
5 3.
03 66.
0
4.
88 24.
5 5.
0
0
27.
2
3.
20
Q
p
16.
1 13.
7 16.
3
17.
2 14.
9 16.
3
15.
0 16.
7 15.
7
16.
5 16.
0
9.
1
8.
4
11.
7 12.
7
6.
5
5.
3
3.
2
17.
0 1.
24
7.
2
1.
47 17.
5 2.
09
6.
6
1.
45
Qr
6.
9 4.
9 4.
1
3.
8 5.
8
4.
1
3.
7 2.
2 5.
1
4.
3 3.
7 4.
5
3.
1
2.
8 4.
6
3.
4
3.
0
4.
8 0.
1
0.
24
-
0.
2
0.
35
4.
1
1.
53
Ch
2.
9 3.
3 1.
2
1.
1 0.
9
-
1.
3 1.
1 1.
1
- 0.
9 1.
2
1.
9
-
-
-
-
0.
6 1.
0
0.
86 1.
7
0.
40 0.
9
0.
73
1.
6
1.
42
Ps
2.
1 1.
5 1.
7
1.
6 0.
9
1.
1
1.
6 1.
0
-
- 1.
3 4.
9
5.
2
6.
5 4.
0
3.
8
2.
5
2.
6 3.
7
0.
85 6.
4
1.
67 3.
7
1.
01
6.
5
0.
95
Pr
- -
1.
2
0.
5
- -
0.
5 -
-
0.
5 -
0.
6
- -
-
1.
1
-
1.
2
-
-
0.
1
0.
16
-
Ks
1.
3
- -
- -
- -
0.
6
- -
- -
0.
8
-
1.
2
2.
6
2.
5
1.
7 -
-
0.
2
0.
24
0.
8
0.
77
Kr
-
0.
6
-
-
-
0.
5
- - -
0.
6 -
1.
2
-
1.
7
1.
2
-
0.
5
-
-
-
-
-
Lv
3.
5
- 1.
7
2.
1 4.
5
3.
9
5.
0 3.
7 1.
2
- 3.
9 0.
6
-
1.
8
-
-
-
0.
6 0.
2
0.
30
-
0.
4
0.
38
-
Lc
3.
3
4.
6
5.
8
2.
0 13.
7 13.
6
11.
9 13.
3 14.
6
13.
5 13.
5
9.
6
8.
9
8.
5
7.
9
9.
8
6.
5
5.
4
20.
4 9.
63
5.
8
5.
35 16.
9 1.
37
6.
8
2.
35
Lm
20.
7 21.
2 19.
9
22.
3 13.
6 15.
1
16.
7 15.
2 17.
7
16.
7 15.
9 25.
7
27.
2
24.
9 23.
8
27.
9
26.
0
25.
8
29.
3 6.
56
7.
2
2.
30 18.
9 7.
45
28.
8
3.
77
Ms
2.
8 4.
9 5.
8
4.
7 4.
8
6.
5
6.
2 8.
7 9.
4
8.
8 9.
4 6.
9
7.
5
8.
9 7.
5
4.
4
9.
3
8.
9 3.
0
1.
92 0.
7
0.
57 3.
3
1.
72
5.
3
1.
10
Mr
4.
3 3.
8 4.
1
4.
2 5.
2
5.
0
5.
6 4.
3 3.
9
3.
1 2.
3 4.
9
3.
8
2.
3 4.
4
2.
1
4.
7
3.
2 0.
4
3.
24
-
0.
4
0.
18
3.
0
1.
05
Al
1.
6 0.
9 1.
2
1.
4 2.
1
2.
9
1.
6
- 1.
2
1.
1 1.
6 1.
1
-
1.
1
-
1.
1
0.
5
1.
7
-
-
0.
1
0.
10
0.
8
0.
64
Mt
8.
7 4.
4 9.
2
8.
9
11.
0
9.
3
8.
8
10.
5 8.
9
10.
5 8.
7 6.
1
5.
9
7.
9 6.
8
6.
2
8.
5
9.
5 0.
8
0.
96 4.
0
1.
88 0.
8
1.
03
0.
6
0.
76
Cm
3.
2
11.
1 2.
9
3.
4 3.
9
4.
2
3.
0 2.
4 2.
7
3.
2 2.
9
-
2.
3
- 3.
1
-
3.
5
4.
1
11.
5
1.
63 1.
0
0.
73
12.
1
1.
50
7.
9
2.
25
10
0.
0 10
0.
0 10
0.
0
10
0.
0
10
0.
0 10
0.
0
10
0.
0 10
0.
0 10
0.
0
10
0.
0 10
0.
0 10
0.
0
10
0.
0 10
0.
0 10
0.
0
10
0.
0
10
0.
0
10
0.
0
10
0.
0
10
0.
0
10
0.
0
10
0.
0
Q
61.
1 62.
8 60.
5
63.
2 55.
2 52.
6
52.
3 54.
4 54.
7
57.
3 54.
0 47.
4
47.
8
45.
5 51.
3
43.
7
48.
4
48.
7
36.
6 4.
68 79.
4
3.
26 51.
6 6.
90
48.
0
4.
62
F
4.
3 2.
8 3.
8
2.
7 1.
2
2.
2
2.
8 2.
2
-
1.
5 1.
7 8.
3
7.
4
10.
4 8.
2
8.
7
7.
4
7.
5 4.
4
1.
04 6.
7
1.
89 5.
0
1.
58
8.
9
1.
84
L
34.
6 34.
4 35.
7
34.
1 43.
6 45.
2
44.
9 43.
4 45.
3
41.
2 44.
3 44.
3
44.
8
44.
1 40.
5
47.
6
44.
2
43.
8
59.
0 5.
21 13.
9
3.
47 43.
4 7.
62
43.
1
4.
91
10
0.
0 10
0.
0 10
0.
0
10
0.
0
10
0.
0 10
0.
0
10
0.
0 10
0.
0 10
0.
0
10
0.
0 10
0.
0 10
0.
0
10
0.
0 10
0.
0 10
0.
0
10
0.
0
10
0.
0
10
0.
0
10
0.
0
10
0.
0
10
0.
0
10
0.
0
Q
m
37.
1 40.
0 37.
7
39.
5 33.
6 30.
0
30.
5 30.
3 31.
9
34.
8 31.
5 34.
7
35.
0
30.
8 35.
0
40.
0
41.
1
43.
4
16.
0 5.
93 70.
0
3.
31 28.
8 6.
04
38.
1
5.
24
F
4.
3 2.
8 3.
8
2.
7 1.
2
2.
2
2.
8 2.
2
-
1.
5 1.
7 8.
3
7.
4
10.
4 8.
2
8.
7
7.
4
7.
5 4.
4
1.
04 6.
7
1.
89 5.
0
1.
58
8.
9
1.
84
L
t
58.
6 57.
2 58.
5
57.
8 65.
2 67.
8
66.
7 67.
5 68.
1
63.
7 66.
8 57.
0
57.
6
58.
8 56.
8
51.
3
51.
5
49.
1
79.
6 6.
50 23.
2
4.
42 66.
3 7.
26
53.
0
5.
37
10
0.
0 10
0.
0 10
0.
0
10
0.
0
10
0.
0 10
0.
0
10
0.
0 10
0.
0 10
0.
0
10
0.
0 10
0.
0 10
0.
0
10
0.
0 10
0.
0 10
0.
0
10
0.
0
10
0.
0
10
0.
0
10
0.
0
10
0.
0
10
0.
0
10
0.
0
THE OLIGOCENE-MIOCENE GHOMARIDE NAPPE COVER (INTERNAL RIF, MOROCCO) 99
rocks are hardly defined because of their alteration. Some of
the pebbles show evidence of porphyritic structure (Fig. 7a),
due to the presence of plagioclase phenocrysts in a holocrys-
talline to oligohyaline fine-grained groundmass, mainly
formed by a felt of twinned plagioclases, opaque minerals and
femic minerals, these last nearly always altered and replaced
into a calcite-vermiculite aggregate and locally into chlorite.
Other volcanic pebbles show an ophitic-like texture, made
up by a subhedral plagioclase felt with the interstices filled by
opaque minerals and by mafic minerals almost completely al-
tered, whereas in other volcanics it is also possible to observe
an abundance of gas-bubble vesicles filled by secondary cal-
cite (Fig. 7b).
Viñuela-Sidi Abdesslam Formation Cycle
Within the Sidi Abdesslam Formation the seven sandstone
samples have been collected from the Boujarrah outcrop, al-
ready studied by Maate et al. (1995) and dated as lower Burdi-
galian, and from the Sidi Abdesslam Section (Mediterranean
coast, 4 km S of Martil; Chalouan 1987; Martin-Algarra 1987;
Maate et al. 1995; Maate 1996; Puglisi et al. 2001).
The sandstones of both these outcrops are characterized by
abundant quartzose-lithic detritus coupled with a low content
of feldspars and their compositions are very similar
(Q
48.0
F
8.6
L
43.4
-Qm
33.9
F
8.6
Lt
57.5
andQ
46.9
F
7.7
L
45.4
-Qm
33.3
F
7.7
Lt
50.6
,
for the Boujarrah and the Sidi Abdesslam outcrops, respec-
tively).
The slightly more lithic nature of the sandstones of the
Viñuela-Sidi Abdesslam Formation Cycle could tentatively be
considered as an element of discrimination even if the popula-
tions of lithic grains are essentially indistinguishable qualita-
tively in the two sets of analysed sandstones (Fig. 7c,d). These
rocks show strong affinities with the sandstones of the Ciudad
Granada-Fnideq Formation Cycle and their provenance also
appears to be linked to metasedimentary and epimetamorphic
rocks rather than to plutonic and/or high grade metamorphic
sources (Fig. 8).
Furthermore, the very poor sorting, the low roundness of
the clasts (usually angular to subangular shaped detrital
grains) and the presence of siliciclastic matrix characterize a
very low textural maturity for these sandstones, suggesting
also in this case very short transports, probably related to a
rugged topography and to a very unstable tectonic setting.
Fig. 7. Thin section photomicrographs of two different volcanic pebbles collected from the Beni Maâdane Section and of two sandstones
representative of the two sedimentary cycles. Volcanic rocks show evidence of (a) slightly porphyric structure (plagioclase phenocrysts
floating in a oligohyaline fine-grained groundmass with feldspars, femic and opaque minerals) and (b) abundance of gas-bubble vesicles filled
by secondary calcite. Sandstones of both the Fnideq (c) and Sidi Abdesslam (d) Formations show a mainly quartzose-lithic composition.
100 ZAGHLOUL et al.
Tectonic setting
Modern orogenic models (Dewey 1988; Michard et al.
2002) suggest that lithosphere thickening and extensional tec-
tonics controlled by internally generated forces are contempo-
raneous and subsequent to the regionally compressive regimes
linked to the north-south convergence of the African and Eu-
ropean plates (Platt & Vissers 1989). Thus, Oligocene com-
pressive events responsible for the deformation and stacking
of the Ghomaride nappes in the internal Rifian zones have
been followed by exhumation and uplift processes of the fold-
thrust belt which occurred in an extensional geodynamic con-
text during Late Oligocene times (Doglioni et al. 1999; Chal-
ouan et al. 2001).
This mainly extensional tectonic regime was dominant and
lasted up to Middle Burdigalian times being accompanied by
the input of detrital supply from the uplifted blocks toward
small basins located above the fold-thrust belt itself. Traces of
extensional tectonic events predating the onset of the Late
Fig. 8. QuartzFeldsparLithic fragments diagram showing the
framework modes for the analysed sandstones from the Oli-
gocene-Miocene cover of the Ghomaride Units. The arrows show
possible evolutive trends. Open and solid circles and squares =
new data, grey squares and circles = data from literature, as shown
on the panel under the QFL plot.
Oligocene unconformable sedimentation above the Ghomar-
ide nappes are testified by the presence of:
decimetric to plurimetric high angle conjugated NNW-SSE
normal faults, affecting the Paleozoic basement near the
Fnideq village (Chalouan 1986) and sutured by the Late
Oligocene-Aquitanian deposits of the Fnideq Formation
(Feinberg et al. 1990),
tardi-metamorphic flexures, evolving to ductile-brittle nor-
mal faults filled by quartzose-feldspatic veins and revealing
a mainly NE-SW extensional trend, observed within the
gneiss and micaschists of the lower Sebtide Units at the
Cabo Negro and Bou Ahmed localities, north and south of
Tetouan (Benmakhlouf 1990; Benmakhlouf & Chalouan
1991) and in the Beni Mzala area (Zaghloul 1994).
Further extensional episodes are well marked in both the
above described sedimentary cycles. In fact, at the base of the
Fnideq Formation the presence of syn-sedimentary normal
faults with a NE-SW extensional axis (Feinberg et al. 1990)
could imply the temporal continuum of the same extensional
event. The coexistence of NW-SE regional compressive con-
straints, almost orthogonal to this extensional trend, is sug-
gested by the occurrence of decimetric folds with the NE-SW
axis (Ouazani-Touhami 1994; Chalouan et al. 1995). On the
contrary, the overlying pelitic interval (more than 190 m
thick) with thin-bedded and fine-grained reddish turbidites
could record an early subsidence episode, contemporaneous
to a period of tectonic quiescence.
Furthermore, at the top of the Fnideq Formation in the Beni
Maâdane area, that is within the upper calcareous conglomer-
ate interval, as well as at the base of the Sidi Abdesslam For-
mation (Fig. 9) several decimetric syn-sedimentary normal
faults of Aquitanian and Burdigalian age and with a mainly
NW-SE extensional trend have been found (Benmakhlouf
1990; Ouazani-Touhami 1994; Chaouni 1996). This last ex-
tensional episode probably reflects a tectonic reactivation of
the tilted listric normal faults by increasing of subsidence and
rejuvenation of relief giving a rugged topography as testified
by the thick calcareous conglomerates in the upper interval of
the Fnideq Formation (Fig. 10). This event would have been
followed by a period of tectonic quiescence which marks the
end of this cycle, materialized by the occurrence of more than
20 m of yellowish marls with thin-bedded turbidites above a
thick (8.5 m) arenaceous body (Puglisi et al. 2001). Note that
the highest levels of the Viñuela-Sidi Abdesslam Formation
Cycle in the Sidi Abdesslam outcrops also show syn-sedimen-
tary normal faults with an ENE-WSW (Ouazani-Touhami
1994; Ouazani-Touhami & Chalouan 1995) to E-W extension
(Chaouni 1996).
Successively, during and after Lower Miocene sedimenta-
tion, a drastic contraction was responsible of the piling-up of
the GhomarideSebtideDorsale Units and of their overthrust
onto the Flysch and the External Domains. The main defor-
mations of the Ghomaride realm, which post-date the nappe
stacking and their overthrust onto the Sebtide Units, are char-
acterized by NW to NE trending open folds, coupled with
brittle thrusts and back-thrusts (locally, low angle normal
faults) and by sinistral and dextral strike-slip fault systems, as
recognized at the Jebha-Chrafat and Jebel Fahies localities, to
the south and north of the Rifian Chain, respectively (Olivier
THE OLIGOCENE-MIOCENE GHOMARIDE NAPPE COVER (INTERNAL RIF, MOROCCO) 101
1982; Morley 1987; Frizon de Lamotte 1987; Zaghloul 1994;
Zaghloul & Chalouan 1997). These deformations also affect
the Oligocene-Miocene Ghomaride nappe covers as testified
by the presence of a lot of decimetric to metric sinistral and
dextral strike-slip faults (Benmakhlouf 1990; Chaouni 1996).
Discussion
The above reported facies analyses yield a better definition
of the sedimentological features of the two sedimentary cycles
characterizing the Oligocene-Miocene successions of the
Ghomaride nappe cover. High density turbiditic flows (very
coarse- and coarse-grained facies such as disorganized and or-
ganized conglomerates and pebbly sandstones) are dominant
in the Ciudad Granada-Fnideq Formation Cycle, whereas a
Fig. 9. Scheme of distribution of the syn-sedimentary normal faults located within the Oligocene-Miocene Ghomaride nappe cover (after
Benmakhlouf 1990, Ouazani-Touhami 1994 and Chaouni 1966, with the integration of new data marked as n.d.). At the bottom, on the right,
the geological sketch map with the location of the stations: 1 Pliocene and Quaternary deposits; 2 Oligocene-Miocene Ghomaride
nappe cover; 3 Ghomaride Units; 4 Sebtide Units; 5 Numidian Flysch; 6 Dorsale Calcaire; 7 Flysch Domain; 8 location
of the stations.
thinning- and fining-upward megasequence with massive
polygenic conglomerates and breccias grading upward to
thin-bedded calcareous turbidites with nodular yellowish-
brownish marls and silexite levels characterize the Viñuela-
Sidi Abdesslam Formation Cycle.
Thus, the whole successions of both the analysed cycles
seem to have been controlled by highly concentrated turbidity
currents with the exception of short vertical interruptions
characterized by mainly pelitic lithofacies with thin-bedded
turbidites, which mainly mark the highest stratigraphic levels.
At the top of the Sidi Abdesslam Formation, in fact, the suc-
cession acquires sedimentological characters probably linked
to low density turbidity currents.
Petrographic analyses indicate a very similar sedimentary
supply for the sandstones of both the Ciudad Granada-Fnideq
Formation and Viñuela-Sidi Abdesslam Formation Cycles,
102 ZAGHLOUL et al.
mainly consisting of metasedimentary and epimetamorphic
detritus with carbonate clasts, rather than of plutonites and
high grade metamorphites as testified by the scarcity of feld-
spar grains. These data could justify the hypothesis of a drain-
age basin made up by the Ghomaride realm rocks, believed to
be the sediment sources rather than the Sebtide Domain, and
by their mainly carbonate Mesozoic sedimentary covers.
Such a paleogeographical hypothesis could help to interpret
the analysed successions as elements of slope apron deposi-
tional systems pounded between fault tilted blocks, controlled
by gravity and debris flow processes and related to backarc
basins.
Thus, the sedimentary infilling of these basins, considered
to be syn- to late-orogenic because of their contemporaneity
with the main orogenic events of uplift and nappe exhumation
(Puglisi et al. 2001), is mainly controlled by normal faults at
the rear of the chain which provides spectacular sediment dis-
persal by means of gravity mass flows.
Therefore, the paleogeographical scenario is closely con-
nected to a geodynamic context where the crust, very thick-
ened by compression and subduction processes, before and
during the stacking of the Ghomaride nappes onto the Sebtide
Units, could have suffered an important extensional buoyancy
of the folded overthrust belt responsible for its progressive up-
lift in the innermost areas. In this way the highly elevated
parts of this tectonic edifice (Ghomaride Units p.p.) could
have been progressively uplifted and suffered a continuous
rapid erosion during Oligocene times, feeding small intramon-
tane satellites basins produced by extensional effects and
located behind the piled nappes, above the GhomarideSebt-
ide Units.
In the Gibraltar Arc, in fact, the exhumation of the Sebtide
(Rif) and Alpujarride (Spain) Units, the consequent tectonic
deformation and the stacking of the GhomarideMalaguide
nappes in the internal BeticRifian zones were concomitant
with the input of detrital supply within small basins (Mar-
tin-Algarra et al. 2000; Puglisi et al. 2001). Thus, the conse-
quent syn- to late-orogenic sedimentation recorded in the two
successive sedimentary cycles above described could have
been contemporaneous with the younger thrusts achieving the
deformation of the more external unites of the internal zones.
In conclusion, it is possible to admit that a dominant mainly
extensional tectonic activity lasted from the Late Oligocene
up to Middle Burdigalian times with permutation of the exten-
sion directions during the Chattian-Aquitanian boundary, re-
lated to the similar values of the intermediate and lower stress-
es (
σ
2
≈σ
3
).
Owing to this extensive normal faulting, the Sebtide Units
and the overlying metamorphic slices, during their uplift, un-
derwent a considerable thinning up to 10 km (Chalouan et al.
1995). In fact, the extensional episodes affecting the Sebtide
Ghomaride nappes, here aged Late Oligocene up to Lower
Miocene times, perfectly coincide with the radiometric ages
measured in the Sebtide Units (about 22 Ma in average; Mi-
chard et al. 1983, 1991; Saddiqi 1988), representing the pas-
sage during their uplift at the depth of about 10 km (Chalouan
et al. 1995). Successively, the distension reached the most ex-
ternal point of the Internal Rif (i.e. the boundary zone between
Fig. 10. Block diagram showing the paleogeographical setting of the internal part of the Ghomaride realm during the early rifting stage
related to the opening of the Alboran Sea of the north-occidental margin of Mesomediterranean terrane. A: Crystalline basement of the
Ghomaride Domain: 1 plutonic rocks (granites and granitoid rocks); 2 high grade metamorphic rocks (augen gneiss and mic-
aschists); 3 low grade metamorphic rocks, such as metasedimentary (metapelites) and phyllites. B: Pre-nappes Triassic to Paleogene
sedimentary cover of the Ghomaride Domain: 4 carbonate and siliciclastic deposits (TriassicUpper Eocene); C: syn- to late-orogenic
siliciclastic flysch of the Ghomaride Domain: 5 thin-bedded sandstones with marly-pelitic intervals, 6 siliciclastic and carbonate-
clastic conglomerates, 7 fine- to medium-grained sandstones, microbreccias and microconglomerates.
THE OLIGOCENE-MIOCENE GHOMARIDE NAPPE COVER (INTERNAL RIF, MOROCCO) 103
the Dorsale Calcaire and the Flysch Domain) during
Aquitanian times, when blocks and olistoliths of the Dorsale
Calcaire nourished the more proximal area of the flysch ba-
sin (the Predorsalian Domain, Auct.)
2
.
Some of these rifts and particularly the more subsident, lo-
cated in the innermost part of this Domain (in relation to the
present geography) and oriented in the same way to the coast
line (e.g. deposit of the synclinal of HaddouFnideq, of Sidi
Abdesslam, Beni Maâdane, and Jebha) seem to be precursors
of continental troughs which evolved into the present Albo-
ran Sea. As suggested for the Calabria-Peloritani Arc by
Weltje (1992) a pattern similar to the arc migration model
(Malinverno & Ryan 1986) could be proposed for the Oli-
gocene-Miocene evolution of the Gibraltar Arc. It allows us to
adequately explain the roll back which occurred during Oli-
goceneMiocene times (De Jonge & Wortel 1990; Royden
1993; Lonergan & White 1997; Frizon de Lamotte 2000), the
southward Maghrebian thrusting and the opening of the Albo-
ran Sea and the Algero-Provençal Basin (Burrus 1984; Bouil-
lin 1984; Rehault et al. 1984).
Conclusions
Thus, in conclusion, the sedimentological and petrographic
data obtained in this study suggest for the Oligocene-Miocene
deposits of the Ghomaride nappe cover the following re-
marks:
provenance of the clasts from the same Ghomaride realm
rocks,
gravity mass flows, mainly highly concentrated turbidity
currents were responsible for the short transport of the sedi-
ments within,
small backarc basins, strongly controlled by extensional
tectonics, and
penecontemporaneous with the orogenic events of uplift
and exhumation of the folded overthrust belt.
Acknowledgments: Financial support was provided by the
Italian MURST Grant to D. Puglisi and by REMER Grant
(20002001) provided by the Moroccan-French Scientific
Cooperation framework. We recognize the helpful of B. El
Moumni (Scientific Coordinator of the REMER Project at the
University of Abdelmalek Essaadi) and the careful revision of
A.H.F. Robertson (Edinburgh), A. Michard (Paris) and of an
anonymous referee, whose rigorous and constructive reviews
strongly improved the manuscript. The first author thanks S.
Lazaar for her stimulating support.
References
Azzouz O. 1992: Lithostratigraphie et tectonique hercynienne des
terrains paléozoïques Ghomarides du massif de Bokoya (Rif
interne, Maroc). Thèse de 3
ème
Cycle, Université Med. V de Ra-
bat (Maroc), 1208.
Belhadad F. 1983: Etude géologique des zones internes du Rif sep-
tentrional (Maroc) au cours de lOligocène et du Miocène in-
férieur. Le Jbel Zem-Zem. Thèse Doct. 3
ème
Cycle, Université
de Rabat (Maroc), 1120.
Benmakhlouf M. 1990: Genèse et évolution de laccident de Tet-
ouan et son rôle transformant au niveau du Rif septentrional
(Maroc). Thèse de 3
ème
cycle, Université Med. V de Rabat (Ma-
roc), 1163.
Benmakhlouf M. & Chalouan A. 1991: Mise en évidence dune dis-
tension tardi- métamorphique précoce dans les Sebtides in-
férieures (Rif interne, Maroc). Newsletter (Lausanne) 2, 10,
3342.
Ben Yaich A. 1981: Etude géologique de la Dorsale Calcaire entre
Tlata Taghramt et Ben Younis (Haouz, Rif, Maroc). Thèse de
3
ème
Cycle, Université Med. V de Rabat (Maroc), 1207.
Blow W.H. 1969: Late middle Eocene to recent planktonic foramin-
iferal biostratigraphy. In: Bronniman II Renz, (Ed.): Proc.
First Int. Conf. Plank. Microfossils, 1, 199422.
Bonardi G., Giunta G., Messina A., Perrone V. & Russo S. 1996:
The Calabria-Peloritani Arc and its correlation with Northern
Africa and Southern Europe (Field Trip Guidebook). IGCP
Project n° 276, Newsletter, v. 6 spec. issue, Messina, 2786.
Bouhdadi S. 1985: Rapports géologiques de la zone paléozoïque et
de la Dorsale Calcaire au SE de Tetouan (Rif interne, Maroc).
Thèse Doct. Ing., Université Paul Sabatier de Toulouse
(France), 1144.
Bouillin J.P. 1984: Nouvelle interprétation de la liaison Apennin-
Maghrébides en Calabre: conséquences sur la paléogéographie
téthysienne entre Gibraltar et les Alpes. Rev. Geol. Dyn.
Geogr. Phys. 25, 321338.
Burrus J. 1984: Contribution to a geodynamic svnthesis of the
Provençal Basin (northwestern Mediterranean). Mar. Geol. 55,
247269.
Cavazza W., Blenkinsop J., De Celles P. G., Patterson R.T. & Rein-
hardt E. G. 1997: Stratigrafia a sedimentologia della sequenza
sedimentaria oligocenica-quaternaria del bacino calabro-ioni-
co. Boll. Soc. Geol. It., 116, 5177.
Chalouan A. 1985: Indices dune tectonique synsédimentaire dans
le Permo-trias du Rif interne (Maroc). Bull. Inst. Sci. Rabat 9,
2531.
Chalouan A. 1986: Les nappes ghomarides (Rif septentrional, Ma-
roc). Un terrain varisque dans la chaîne alpine. Thèse ès-Sc.,
Université Louis Pasteur de Strasbourg (France), 1371.
Chalouan A. 1987: Mise en évidence dans le Rif interne dune tec-
toniques distensive anté-pliocène. Les premiers stades
deffondrement de la mer dAlboran. 4
éme
Colloque des Bassins
Sédimentaires Marocains, Tetouan (Maroc), 30 Octobre1 No-
vembre 1987.
Chalouan A., Benmakhlouf M., Mouhir L., Ouazani Touhami A.,
Saji R. & Zaghloul M.N. 1995: Les étapes tectoniques de la
structuration alpine du Rif interne (Maroc). VI Coloquio inter-
national sobre el enlace fijo del estrecho de Gibraltar Ed.
S.E.C.G., SA. Madrid, ESPAÑA, VII, 136192
Chalouan A. & Michard A. 1990: The Ghomarides nappes, Rif
coastal range, Morocco: a Variscan chip in the Alpine belt.
Tectonics 9, 15651583.
Chalouan A., Michard A., Feinberg H., Montigny R. & Saddiqi O.
2001: The Rif mountain building (Morocco): a new tectonic
scenario. Bull. Soc. Géol. France 172, 5, 603616.
Chaouni A. 1996: Apport des données LANDSAT M. S. S., RA-
DAR ERS1-SAR; modèle numériques de terrain; mor-
phométriques structurales de terrain à la compréhension de la
cinématique des principales failles de la péninsule de Tanger
depuis lOligocène supérieur jusquà lActuel (Rif Septentrion-
al Maroc). Thèse de 3
ème
Cycle, Université Med. V de Rabat
(Maroc), 1265.
De Jonge M. & R. Wortel M.J.R. 1990: The thermal structure of the
2
Moreover, it seems that also the more internal flysch has been deposited in a subsident foredeep submitted to a divergent geodynamic
context, at least during Upper OligoceneAquitanian times (Zaghloul et al. 2002).
104 ZAGHLOUL et al.
Mediterranean upper mantle: a forward modeling approach.
Terra Nova 2, 609616.
Dewey J.F. 1988: Extensional collapse of orogens. Tectonics 7,
11231139.
Dickinson W.R. 1970: Interpreting detrital modes of graywacke and
arkose. J. Sed. Petrology 40, 2, 695707.
Dickinson W.R. & Suczek C.A. 1979: Plate tectonics and sandstone
composition. Amer. Assoc. Petrol. Geol. Bull. 63, 21642192.
Didon J., Durand Delga M. & Kornprobst J. 1973: Homologies
géologiques entre les deux rives du Détroit de Gibraltar. Bull.
Soc. Géol. France (7), XV, 2, 77105.
Doglioni C., Fernandez M., Gueguen E. & Sabat F. 1999: On the in-
terference between the early Apennines-Maghrebides backarc
extension and the Alp-Betics orogen in the Neogene geody-
namics of the western Mediterranean. Bull. Soc. Geol. It. 118,
7589.
Durand-Delga M. 1980: La Méditerranée occidentale: étapes de sa
genèse et problèmes structuraux liés à celle-ci. Mém. Soc.
Géol. France 10, 203224.
Durand-Delga M. & Kornprobst J. 1963: Esquisse géologique de
la région de Ceuta (Maroc). Bull. Soc. Géol. France (7), 5,
10491057.
Durand-Delga M., Kornprobst J., Leikine M. & Raoult J.F. 1964: Le
Lias des unités paléozoïques au nord de Tetouan (Rif interne,
Maroc). C. R. Acad. Sci. Paris 358, 59255929.
Durand-Delga M. & Olivier Ph. 1988: Evolution of the Alboran
Block margin from Early Mesozoic to Early Miocene time. In:
Battachayi S., Friedman G.M., Neugebauer H.J. & Seilacher A.
(Eds.): Lecture Notes in Earth Sciences, n 15; Jacobshagen
V.H. (Ed.): The Atlas System of Morocco. Springer-Verlag,
465480.
Feinberg H., Maate A., Bouhdadi S., Durand-Delga M., Maate M.,
Magné J. & Olivier Ph. 1990: Signification des dépôts de
lOligocène supérieur Miocène inférieur du Rif interne
(Maroc), dans lévolution géodynamique de larc de Gibraltar.
C. R. Acad. Sci. Paris 310, série Il, 14871495.
Feinberg H. & Olivier Ph. 1983: Datation des termes aquitaniens et
burdigaliens dans la zone prédorsalienne Bético-rifaine et ses
conséquences. C. R. Acad. Sci. Paris 269, 473476.
Frizon de Lamotte D. 1987: La structure du Rif externe: mise au
point sur le rôle des décrochements et des glissements gravi-
taires. J. Afric. Earth. Sci. 6, 5, 755766.
Frizon de Lamotte D., Saint Bezar B., Bracène R. & Mercier E.
2000: The tow main steeps of the atlas building and geodynam-
ics of the western Mediterranean. Tectonics 19, 740761.
Gazzi P. 1966: The upper Cretaceous Flysch sandstones (Modena
Apennine); comparison with the Monghidoro Flysch. Miner-
al. Petrogr. Acta (Bologna) 12, 6997 (in Italian).
Gazzi P., Zuffa G.G., Gandolfi G. & Paganelli L. 1973: Provenance
and dispersal of the sands along the Adriatic littoral between
the Isonzo and Foglia rivers: regional framework. Mem. Soc.
Geol. It. 12, 137 (in Italian).
Gelard J.P. 1979: Géologie du Nord-Est de la Grande Kabylie (un
segment des zones internes de lorogène littorale maghrébin).
Thèse Doct., Université de Dijon 1335.
Géry B., Feinberg H., Lorenz C. & Magné J. 1981: Définition dune
série-type de l«Oligo-Miocène Kabyle» anténappes dans le
Djebel Aïssa-Mimoun (Grande Kabylie, Algérie). C. R. Acad.
Sci. Paris 292,15291532.
Graham S.A., Ingersoll R.V. & Dickinson W.R. 1976: Common
provenance for lithic grains in Carboniferous sandstone from
the Ouachita Mountains and Black Warrior Basin. J. Sed. Pe-
trology 46, 620632.
Guerrera F., Martin-Algarra A., Martin-Martin M. & Puglisi D.
1997: The Oligo-Miocene geodynamic evolution of the Inter-
nal Zones of the eastern Betic Cordillera: new data from tur-
biditic successions. Interim Colloquium R. C. M. N. R. S. Neo-
gene Basins of the Mediterranean Region: Controls and Corre-
lation in space and time, Catania (Italy) 49 November 1997,
6768.
Guerrera F., Martin Algarra A. & Perrone V. 1993: Late Oligocene
Miocene syn-/-late-orogenic successions in Western and Cen-
tral Mediterranean Chains from the Betic to the Southern
Apennines. Terra Nova 5, 525545.
Kornprobst J. 1974: Contribution à létude pétrographique et struc-
turale de la zone interne du Rif (Maroc Septentrional). Notes et
Mém. Serv. Géol. Maroc 251, 1256.
Leeder M. 1999: Sedimentology and sedimentary basins: From tur-
bulence to tectonics. Ed. Blackwell Sciences Ltd., 1592.
Lonergan L. & White N. 1997: Origin of the Betic-Rif mountain
belt. Tectonics 16, 3, 504522.
Maate A. 1984: Etude géologique de la couverture mésozoïque et
cénozoïque des unités ghomarides au Nord de Tetouan (Rif in-
terne, Maroc). Thèse 3ème Cycle, Université de Toulouse
(France), 1161.
Maate A. 1996: Stratigraphy and palaeogeographic evolution of
the Ghomaride Domain (Internal Rif, Morocco). Ph. Doct.
Thesis, Universidad de Granada (España), 1397 (in Spanish).
Maate A., Martin-Algarra A. & Ouazani-Touhami A. 1991: Les
paléokarsts de lunité de Buluazen (Haouz, Rif interne, Ma-
roc). Conséquences paléogéographiques. C. R. Acad. Sci. Paris
313, Série II, 10591064.
Maate A., Martin-Perez J. A., Martin-Algarra A., Serrano F., Agua-
do R., Martin-Martin M. & El Hajjaji Kh. 1995: Le Burdigalien
inférieur de Boujarrah (Rif septentrional, Maroc) et la signifi-
cation paléotectonique des séries miocènes transgressives sur
les zones internes bético-rifaines. C. R. Acad. Sci. Paris 320,
Série IIa, 1522.
Malinverno A. & Ryan W. B. F. 1986: Extension in the Tyrrhenian
Sea and shortening in the Apennines u result of arc migration
driven by sinking of the lithosphere. Tectonics 5, 227245.
Martin-Algarra A. 1987: Evolucion geologica alpina del contacto en-
tre las Zonas Internas y las Zonas Externas de la Cordillera Beti-
ca. Ph. Doct. Thesis, Universidad de Granada (España), 11171.
Martin-Algarra A., Messina A., Perrone V., Russo S., Maate A. &
Martin-Martin M. 2000: A lost realm in the Internal Domains
of the Betic-Rif orogen (Spain and Morocco): evidence from
conglomerates and consequences for Alpine geodynamic evo-
lution. J. Geol. 108, 4, 120.
Martini E. 1971: Standard Tertiary and Quaternary calcareous nan-
noplankton zonation. In: Farinacci A. (Ed.): Proc. II Planktonic
Conference, Roma, 1970, 739785.
Michard A., Chalouan A., Feinberg H., Goffé B. & Montigny R.
2002: How does the Alpine belt end between Spain and Moroc-
co? Bull. Soc. Géol. France 173, 1, 315.
Michard A., Chalouan A., Montigny R . & Ouazani-Touhami A.
1983: Les nappes cristallophylliennes du Rif (Sebtides, Ma-
roc), témoins dun édifice alpin type pennique incluant le man-
teau supérieur. C. R. Acad. Sci. Paris 296, II, 13371340.
Michard A., Goffé B., Chalouan A. & Saddiqi O. 1991: Les corréla-
tions entre les Chaînes bético-rifaines et les Alpes et leurs con-
séquences. Bull. Soc. Géol. France 162, 11511160.
Morley C.K. 1987: Origin of a major cross-element zone: Moroccan
Rif. Geology 15, 761764.
Mutti E. 1992: Turbidite sandstones. Agip S.p.A Milano Istituto di
Geologia, Università di Parma, 1275.
Ogniben L. 1973: Geologic framework of Calabria inferred from
recent data. Geol. Romana 12, 243585 (in Italian).
Olivier Ph. 1979: Nouvelles données sur le paléogène rifain (Ma-
roc). C. R. Soc. Géol. France fasc. 2, 6063.
Olivier Ph. 1982: Laccident de Jebha-Chrafate (Rif, Maroc). Rev.
Géol. Dyn. Géogr. Phys. 23, Fasc. 2, 97106.
THE OLIGOCENE-MIOCENE GHOMARIDE NAPPE COVER (INTERNAL RIF, MOROCCO) 105
Olivier Ph., Cantagrel J.M. & Kornprobst J. 1979: Problèmes posés
par la découverte de blocs de granite dans un conglomérat ter-
tiaire, couverture de lunité ghomaride dAkaïli (Rif interne,
Maroc). C. R. Acad. Sci. Paris 288, 299302.
Ouazani-Touhami A. 1994: Lévolution géodynamique alpine des
nappes ghomarides (Rif interne septentrional, Maroc). Thèse
de 3
ème
Cycle, Université Med.V. Rabat (Maroc), 1126.
Ouazani-Touhami A. & Chalouan A. 1995: La distension oligo-mi-
ocène dans les nappes ghomarides (Rif interne septentrional,
Maroc). Geogaceta 17, 113116.
Patterson R.T., Blenkinsop J. & Cavazza W. 1995: Planktic fora-
miniferal biostratigraphy and
87
Sr/
86
Sr isotopic stratigraphy of
the Oligocene-to-Pleistocene sedimentary sequence in the
southeastern Calabrian microplate, southern Italy. J. Paleont.
69, 1, 720.
Pickering K.T., Hiscott R.N. & Hein F.J. 1989: Deep-marine envi-
ronments: Clastic sedimentation and tectonics. Unwin Hyman,
London, 1352.
Platt J.P. & Vissers R.L.M. 1989: Extensional collapse of thickened
continental lithosphere: a working hypothesis for the Alboran
Sea and Gibraltar Arc. Geology 17, 540543.
Puglisi D. 1987: Cretaceous-Tertiary turbidite successions of the
north-east Sicily during the evolution of the southern sector
of the Calabria-Peloritani Arc and of the Sicilian Maghrebian
Chain. Giornale di Geologia 49, 1, 167185 (in Italian).
Puglisi D., Zaghloul M.N. & Maate A. 2001: Evidence of sedimen-
tary supply from plutonic sources in the Oligocene-Miocene
flysch of the Rifian Chain (Morocco): provenance and palaeo-
geographic implications. Boll. Soc. Geol. It. 120, 5568.
Raymond D. 1976: Evolution sédimentaire et tectonique du nord-
ouest de la Grande Kabylie (Algérie) au cours du cycle alpin.
Thèse Doct., Université de Paris (France), 1152.
Rehault J.P., Boillot G. & Mauffret A. 1984: The western Mediter-
ranean basin geological evolution. Marine Geol. 55, 447477.
Royden L.H. 1993: Evolution of retreating subduction boundaries
formed during continental collision. Tectonics 12, 629638.
Saddiqi O. 1988: Tectonique de la remontée du manteau: les péri-
dotites de Beni-Bousera et leur enveloppe métamorphique (Rif
interne, Maroc). Thèse Doct., Université Louis Pasteur, Stras-
bourg (France), 1180.
Tefiani M. 1970: Présence dolistostromes à la base des nappes de
flyschs reposant sur la Dorsale Kabyle au Sud-Est dAlger. C.
R. Somm. Soc. Géol. France 8, 315.
Weltje G.J. 1992: Oligocene to Early Miocene sedimentation and
tectonics in the southern part of the Calabrian-Peloritain Arc
(Aspromonte, southern Italy): a record of mixed mode piggy-
back basin evolution. Basin Research 4, 3768.
Wildi W. 1983: La chaîne tello-rifaine (Algérie, Maroc, Tunisie):
structure, stratigraphie et évolution du Trias au Miocène. Rev.
Géol. Dyn. Géogr. Phys. 24, 3, 201297.
Zaghloul M.N. 1994: Les unités Federico septentrionales (Rif in-
terne, Maroc): Inventaire des déformations et leur contexte
géodynamique dans la chaîne Bético-rifaine. Thèse de 3
ème
Cy-
cle, Université Med. V de Rabat (Maroc), 1218.
Zaghloul M.N. & Chalouan A. 1997: Lévolution tectonique de
laccident de Fahies au cours du Cénozoïque. 14
ème
Colloque
des Bassins Sédimentaires, Faculté des Sciences Ibn Tofail,
Kénitra (Maroc), 168.
Zaghloul M.N., Guerrera F., Loiacono F., Maiorano P. & Puglisi D.
2002: Stratigraphy and petrography of the Beni Ider Flysch in
the Tetouan area (Rif Chain, Morocco). Bull. Soc. Geol. It.
121, 6985.