SECTION 5 - ANNEXE 6: DESCRIPTITION DE CHAQUE UNITÉ

SECTION 5 - ANNEXE 6: DESCRIPTITION DE CHAQUE UNITÉ LITHOSTRATIGRAPHIQUE
DÉFINIE AU NIVEAU NATIONAL
INTRODUCTION
Comme mentionné dans l'appel TDR, les concepts géodynamiques ayant fondamentalement changé
depuis l’époque de la première définition formelle de la stratigraphie au premier niveau pour
l’entièreté du Pays par Lepersonne en 1974, et de nouveaux travaux ayant été publié depuis ayant un
impact sur cette stratigraphie, cette dernière était donc devenue obsolète et sujette à révision.
Tenant compte des nouveaux travaux qui ont été publié depuis sur divers (sous)régions / provinces
géologiques, nous avons essayé d’appliquer les directives récentes de l’UISG pour la définition des
unités lithostratigraphiques de premier niveau du pays.
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Des roches, associations de roches, qui ont connu une histoire géologique commune,
considérées d’origine sédimentaire, même si actuellement de faciès haut-métamorphique,
sont à regrouper dans des Supergroupes, etc ...
Des roches, ou groupes de roches dont l’origine est soit difficile à établir, soit des
associations de composition diverses mais qui ont connu une évolution – histoire géologique
commune, similaire, se regroupent dans des Complexes (magmatique, métasédimentaire,
métamorphique, tectonique)
DÉFINITION DES UNITÉS LITHOSTRATIGRAPHIQUES
Pour chaque unité stratigraphique (re)définie au premier niveau , nous donnons
En gras, le nom du Supergroupe / Complexe , accompagné de son code, redéfini
En italique, le nom équivalent et code défini par Lepersonne en 1974.
Les sous-divisions connues – publiées - de cette unité
Accompagné d’une brève description des connaissances actuelles, citant les sources principales les
plus récentes.
L’information est extraite de Deblond (2004, annexe 3) ou de la littérature plus récente renseignées
en annexe 4 . Les extraits sont produits dans la langue originale des publications, les copies
de figures, tableaux sont également extraits de ces références.
ARCHÉEN
Complexe tonalitique de la Haute Luanyi ( Cp-HL)
gneiss de la haute Luanyi - GnF
Delhal (1963), Delhal ( 1991); Walraven and Rumvegeri ( 1993), Rumvegeri (1990)
sous-divisions : aucune connue
This rock unit includes partly migmatitized fine-grained biotite gneisses and pegmatites .
Complexe amphibilotique et gneissique de la Bomu (Cp-Bo)
complexe amphibolitique et gneissique du Bomu - Bo
Thibaut (1983), Lavreau (1982a)
Histoire longue d’environ 1Ga ; Roches de haut métamorphisme + granitoïdes. Appartient aux
greenstones Kibaliens (Lavreau, 1982a). Cartographie de Lepersonne (1974) mise en défaut par
Lavreau (1982a). Age Paléoprotérozoïque d’après BRGM (1980-1982)=> plus que probablement
erroné, cfr datation géochronologiques de Lavreau qui confirme l’age Archéen.
Sous-divisions :
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Gneiss de Nzangi: gneiss mafique avec qq micaschiste, quartzite et granitoïde
Gneiss de Monga (RDC)/ de Ouango (RCA): micaschiste, quartzite et gneiss granitique
Gneiss de Bereme: quartzite micacé, gneiss à hornblendes et biotites ; couffe les gneiss de
Bomu
Gneiss mafique de Bomu : gneiss à amphiboles et clinopyroxènes (cpx) (souventà grenats) =
base
Magmatisme , événements thermiques:
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Granitoïdes précurseurs des gneiss de Nzangi datés à 3.42 Ga (Pb-Pb)
Evènement thermo-tectonique ~3.01 Ga dans les gneiss de Nzangi (Rb-Sr) et ~2.96 Ga
dans les gneiss de Bomu
Batholites granitiques(granite de Bondo) ont intrudé les gneiss de Nzangi vers 2.45 Ga
Déformations mylonitiques ~900 Ma
Supergroupe de la Gangu –( SG-Gn)
 Ganguien - G
quartzite et phyllade + talcschiste, contient des BIF
Lavreau 1982a, Lepersonne 1974 ; BRGM, 1980-1982
Série supracrustale Ganguen considérée comme inclue dans complexe amphibolitique et gneissique
du Bomu (Lavreau 1982a) : recouvre gneiss de Bomu.
Sous-divisions
(Lepersonne1 1974) ; BRGM (1980-1982)
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Unite supérieur: sericitochists, talcschists1 talcschists with feldspar-rich layers/
chloritoschists/ quartzitic sericitoschists
Unité inférieur: quartzitic sericitoschists/ sericite-bearing quartzites, magnetite-bearing
banded iron-rich quartzites .
Sous-divisions mises en question par Lavreau (1982a) : préconise des unités distinctes géographiques
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Bili : fuchsite-bearing quartzites, sericite-bearing schists, talcsch ists, graphitic schists,
Matundu : mainly composed of talcschists
Mupi : not mapped by Lepersonne (1974): talcschists and serpentine-bearing rocks
associated with quartzites and cherts.
Magmatisme :
intrudé par veines de qtz (à galène, 3.2 Ga) et d’aplite et par de petits massifs doléritiques.
Le Supergroupe du Kasai-Lomami
Delhal & Fieremans (1964), Delhal (1977, 1991), Lepersonne (1974), Delhal et al. (1967, 1976, 1986),
Walraven & Rumvegeri (1993), Kabengele et al. (1991), Rumvegeri (1990), Rumvegeri et al. (1991),
Delhal & Ledent (1971, 1973), Delhal & Liégeois (1982), Cahen et al. (1984)
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Le Complexe granitique et migmatitique de Dibaya
Charno-enderbitic and Granulitic Complex; also known as the Kasai-Lomami Gabbronorite
and Charnockite Complex
Granito-gneissic Complex of Western Katanga; also known as Sandoa-Kapanga-Complex
Kanda-Kanda Tonalitic Complex
Contacts entre unités non apparents
Nous n’utiliserons plus ce Supergroupe, composé de complexes ; Dibaya étant redéfini comme
Supergroupe à part entière
Magmatisme
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Tonalities, granodiorites, charno-enderbites: 2,8 – 3,1Ma
Alaskites:, granites, granodoirites : 2.8 Ma
Migmatites : 2.7
Malafundi Granite : 2.6Ma
Intrudé au Kasai et en Angola par des kimberlites du Crétacé
Complexe tonalitique de Kanda-Kanda _ Cp-KK
non cartographié par Lepersonne, 1974
Rumvegeri et al. (1991),
sous-divisions : aucune connue
The Dibaya Granite and Migmatite and the Charno-enderbitic and Granulitic complexes are
separated in the west by the Palaeoproterozoic Lulua-Luiza Supergroup while recent investigations,
conducted by Rumvegeri et al. (1991), show that their contact zone in the east, in the Kanda-Kanda
region, is occupied by a large, single Archaean plutonic complex, referred to as the Kanda-Kanda
Tonalitic Complex. The complex shows an outwards magmatic evolution from tonalite in the core to
granodiorite and finally monzogranite or granite s.s ..
Complexe granito-gneissique de Sandoa – Cp-SA
formations anté-Kibariennes indifférenciées - Ab
complexe de la Lukoshi - Ls
Walraven & Rumvegeri, 1993
Sous-divisions : aucune
The Granito-gneissic Complex of Western Katanga, .also called the Sandoa-Kapanga Complex is
characterized by a rather monotonous lithology and its constituents, granulites, tonalitic to granitic
gneisses, granites and (minor) amphibolites, are metamorphosed to the amphibolite-granulite facies.
Complexe granulitique de la Musefu – Cp-Mu
complexe gabbro-noritique et charnockitique du Kasai-Lomami ; partie charnochite
Walraven & Rumvegeri, 1993
Sous-Divisions : acune
It is composed of hypersthene gneisses (charnockites s.s. and enderbites) and of garnet-bearing
quartzo-feldspathic rocks regularly showing well-developed sillimanite crystals (granulites or
leptinites). The composition of these rocks, which displays a clear silicic character, shows that they
derive in part from sedimentary rocks and are the products of high grade metamorphism of an old
gneissic basement of which the Haute Luanyi gneisses would be a remnant (Delhal, 1963).
Supergroupe de Dibaya – SG-DI
complexe granitique et migmatitique de Dibaya – D
Delhal, 1967, 1991, Kabengele, 1991
Sous-division: aucune
The northern half of the complex is mainly occupied by migmatitic gneisses amongst which
amphibolite zones locally occur. These zones were considered to be residues of crystalline rocks
older than the migmatitisation (Delhal et al., 1967) but are now being questioned (Delhal, 1991). The
migmatites present three types of structures: agmatic, stromatic and schlieren, and all of them
contain pegmatites. Geochemically the migmatites display calc-alkaline features (Kabengele et al.,
1991)
Calc-alcaline granitic rocks (MAlafundi granite) occur in the southern aprt.
Upper Congo Granite-Greenstone (GG) association
Lavreau (1973), Cahen et al. (1976), Poidevin et al. (1981). Lavreau and Ledent (1975), Lavreau et al.
(1980), Lavreau (1982a), Lepersonne (1974); Lavreau and Deblond (2000)
The greenstone belts of the GG domain are restricted to a number of small units set in a granitoid
“matrix”: Tele, Panga, Ituri, Ngayu, Mambasa, Kilo, Zani, Moto, Tina & Isiro. They represent 15-20 %
of the whole and are more abundant in the eastern part of the domain, suggesting that erosion cuts
down to deeper levels in the west. In NE Congo, the greenstone belts are referred to as the Kibalian
of Archaean age (from Kibali river; not to be mistaken with the Mesoproterozoic "Kibaran") or to the
"Ganguan".
Supergroupe de la Kibali – SG-KI
Kibalien - Ki
Sous-divisions
Lavreau :
• Upper Kibalian: sediments, with some andesitic volcanics
• Lower Kibalian: volcanic-granitoid association.
The volcanic members contain distinct andesitic members together with less typical tholeiites. The
metavolcanics of the Lower Kibalian, akin to oceanic tholeiites including high-Mg basalts, have been
subdivided on geochemical grounds (Lavreau and Navez, 1983), into ultramafic, mafic, intermediate
and andesitic terms. The sediments are represented by various pelites and characteristic BIF
BRGM:
Upper Kibalian (Ki2): metavolcanic and metasedimentary
Lower Kibalian (Ki1): paragneissic
Complexe granitoide TTG de l’Uele – Cp-TTG
Non défini par Lepersonne, repris dans ‘roches granitiques affectant le KiIbalien’
Lavreau and Deblond (2000)
Typical TTG suite associated to the greenstones ( type A GG association; c. 95% of the gold
output). The tonalites of this GG association intruded 2.8-2.9 Ga ago (see below).
Contexte géodynamique:
Lavreau and Deblond (2000).
The granite-greenstone (GG) associations have been classified according to their nature and to that
of their basement:
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The type A GG association (c. 95% of the gold output) consists of greenstones with abundant
mafic-ultramafic volcanics and scarce sediments (Lower Kibalian). No basement has been
recognised. Associated granitoids correspond to a typical TTG suite. The tonalites of this GG
association intruded 2.8-2.9 Ga ago.
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The type B GG association comprises mafic-intermediate volcanics besides sediments, mainly
BIFs (Upper Kibalian). Their basement consists either of type A GG association or of medium
to high-grade metamorphic rocks. Associated granodiorites and granites (2.4-2.5 Ga)
representing most of the volume of the entire greenstone belts, intruded this type B
association and its basement
Magmatime:
Wanga tonalite: 2.84-2.89 Ma (dans KI) ; Kilo tonalite : 2.75 Ma
Moto granitoides : 2.51 – 2.63Ma (dans KS) ; Kilo granites : 2.41Ma
Énormes aires de granites indifférenciés.
The West Nile Gneissic Complex
This complex formed the subject of a small number of generally superficial studies. These include
McDonald (1963), Hepworth (1967) and Hepworth & McDonald (1966) for Uganda and Sudan,
whereas specific areas of the DRC were covered from the twenties to the fifties (re-ferences in
Cahen, 1954) and in the eighties (Lavreau 1980, 1982a, 1982b). Correlating the different results turns
out to be a futile exercise.
In the DRC, the West Nile gneissic Complex comprises (Lavreau, 1982b):
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the Garamba gneissic Complex with some mica- and amphibole-rich horizons;
the Dungu Formation, composed of micaschists, quartzites and gneisses (some of them
reworked Garamba gneisses);
the Aru-Zani gneisses, composed of granitic gneisses overlain by micaschists and
amphibolites
A complex association of two or three units of gneisses and migmatites crops out along Lake Albert,
in continuation with the units defined in the West Nile District of Uganda. The Mount Speke gneissic
Complex, which is exposed in the Ruwenzori horst (western branch of East Afri-can Rift), may be
linked to the Garamba gneissic Complex (Lepersonne, 1974)
Supergroupe de la Garamba – SG-GA
complexe gneissique de la Garamba – Ga ;
gneiss du Mont Speke - Sp
formation Dungu (non défini par Lepersonne)
gneiss Aru-Zani (non défini par Lepersonne)
sous-divisions : tentative de définition d’unités tectono-stratigraphiques
Lavreau (1980, 1982a). This study has emphasized its complexity, whatever the scale of
the investigation could be. Aerial photographs interpretation allowed to define six main
tectonic domains and prevailing ENE-trending mylonitic corridors. An attempt has been
performed by this author (op. cit) in order to establish a link between the
lithostratigraphic and tectonic units. This led to the following subdivision (essentially in
DRC) :
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the gneisses and micaschists of the Aka domain;
the Garamba, Faradje and Pays Logo gneisses;
the granitoid gneisses of the area between the Dungu and Nzora rivers;
the augite-diopside-bearing gneisses of the Aba area;
the high-grade gneisses (granulite facies);
the eastern part of the Eastern Grey Gneisses (Uganda) and the Mahagi-Port
gneisses (DRC).
Complexe de Niangara – Cp-NIA
 formations attribuées au Lindien (Ubangien) – L, Lc
Lavreau (1982a) includes the Niangara-Zemio supracrustal series into the West Nile Complex. This
elongated NW to NNW-trending narrow zone (20-50 km) runs across DRC (over c. 300 km) and CAR
(over c. 150 km; Poidevin, 1985) along the edge between the West Nile Complex and the Upper
Congo Granite-Greenstone association.
Sous-division:
Two units separated by an angular unconformity have been identified in this zone (Lavreau, 1982a ; )
they were undifferentiated and previously mapped as Neoproterozoic (Lepersonne, 1974):
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a Neoproterozoic upper unit extending northwards across the Centrafrican border: Rumu
series (DRC) and Morkia series (CAR) (Poidevin, 1985);
a lower unit (Bolume Formation); of inferred Archaean, (Poidevin, 1985) or
Palaeoproterozoic age (BRGM, 1980-1982), composed of strongly folded quartzites, sericitebearing quartzites and white seritoschists.
Supergroupe des Muhila – SG-MU
complexe métasédimentaire et cristallin des Muhila – Mu
Lepersonne, 1971, 1974; Jamotte, 1949).
Sous-divisions : inconnues
Reported rocks (Lepersonne, 1974) include whitish to pinkish jasper with hematite banding, itabirites
(BIF), quartz-injected micaschists and sericitic quartzites. The main trend of the rocks is orthogonal to
the general trend of the Palaeproterozoic Rusizian belt, which the Muhila complex underlies. The
described lithologies are reminiscent of Archaean greenstone belts and Jamotte (1949) already
compared them to the greenstone belts of NE Congo (Upper Congo Granite-Greenstone association)
and of Zimbabwe.
Régions (d’extension limitée) à protolithe granitique archéen
Non cartographié par Lepersonne, 1974
These four presumed Archaean nuclei have been identified in Equator Province (Aderca, 1950;
Thibaut, 1983). They consist of banded coarse-grained biotite-garnet-bearing gneisses in Turkwa,
augen-gneisses in Banda and garnet-bearing two micas banded augen-gneisses associated to
magnetite-bearing metacalc-schists in Dula. The Litima nucleus exposes albite-bearing leptynites.
No radiometric age is available for these rocks, but according to Thibaut (1983) they display
similarities with Centrafican Archaean units in continuity of which they crop out, on the other bank of
Ubangi river. In CAR, this basement is intruded by Archaean granites, a situation arguing in favour of
a minimum Archaean age for this basement (Thibaut, 1983).
These inferred Archaean nuclei, by analogy with the more widespread similar formations identified in
CAR, may thus constitute small-sized inliers occurring within the inferred Palaeoproterozoic Ubangi
Complex, in the core of anticlines (Turkwa, Banda and Dula) or after faulting (Litima).
PALÉOPROTÉROZOIQUE
Complexe gabbro-noritique de Lueta – Cp-GN-LU
complexe gabbro-noritique et charnockitique du Kasai-Lomami ; partie gabbronorite
Delhal et al., 1976; Delhal, 1991, Lepersonne, 1974
A large mafic plutonic complex, composed of gabbronorite (representing about 50 % of the
mafic rocks), garnet–bearing gabbros and amphibolites.
The age of the Gabbronorite Complex, previously considered as Archaean (Lepersonne,
1974), has been requestioned and considered as Palaeoproterozoic (Delhal, 1991).
Sous-divisions: aucune
Supergroupe de la Lulua-Luiza – SG-LL
complexe sédimentaire et volcanique de la Lulua – Lu ;
Luizien – Lz
Delhal, 1963, Delhal et al., 1966, Delhal (1991) and Fieremans (1991)
Sous-divisions:
On the basis of recent age dating and former field observations Delhal (1991) and Fieremans (1991)
have advanced and/or confirmed the existence of a single Palaeoproterozoic Lulua-Luiza Supergroup
(2.2–1.9 Ga) enclosing:
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an upper volcano–sedimentary unit (the Lulua Volcano–sedimentary Group);
o The Lulua volcano–sedimentary Group is composed of schists, quartzites and
interstratified mafic volcanic rocks and has an estimated total thickness ranging
between 4,000 and 7,000 m (Delhal et al., 1966). These authors have recognized
at least two sedimentary graded sequences:
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an upper sequence starting with sandstones, overlying the lower
sequence’s lavas, and overlain by shales and carbonaceous rocks;
a lower sequence which comprises (from bottom to top) conglomerates,
quartzites, sandstones, shales or phyllites and lavas.
a lower and older metasedimentary unit (the Luiza metasedimentary Group and its
equivalent in Katanga, the Lukoshian),
o the Luizian metasediments are composed of mica–bearing quartzites, itabirites
(BIFs), micaschists and local metamorphic conglomerates. This succession rests
unconformably (but in normal contact) on the Gabbronorite Complex.
o The Lukoshian supracrustals, of greenstone affinities exist as abundant
isolated outcropping areas of sedimentary rock (phyllites, graphitic phyllites,
quartzites,...) as well as amphibolitic schists, possibly of igneous origin
The exposed contact between the Lulua and Luiza groups has been interpreted as a structural rather
than stratigraphic contact (Delhal, 1963).
Magmatisme:
The mainly basaltic volcanic activity in the Lulua Group occurred from the time of deposition of the
shales of the lower sequence to that of the shales and carbonaceous rocks of the upper sequence.
The maximum apparent intensity is attained at the end of the lower sequence. Three 2.0 Ga, basaltic
units have been identified (Delhal et al., 1966), :
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the Malafudi basalts, in the east, with an apparent thickness of more than 900 m;
the Yangwegi basalts, in the centre, some 700–850 m thick;
the Kasadi–Sadi basalts, in the west, of unknown thickness.
IN the Luiza group, “post tectonic” granites and pegmatites are dated at 2.0 Ga.
Supergroupe de Kimeza – SG-KM
complexe de gneiss et migmatites de Mpozo-Tombagadio - PT
Cahen et al., 1984
In the Pan-African West Congo orogenic belt, in Bas Congo, a major angular unconformity separates
the Neoproterozoic Zadinian Supergroup from the underlying c. 2.1 Ga Eburnian gneissic basement .
Different names have been given to this basement giving rise to a confusing terminology. In the more
recent literature of the Bas Congo region, the basement is generally referred to as the Kimezian
Supergroup, affected by the Tadilian orogeny.
Sous-division: aucune
Complexe de l’Ubangui – Cp-UB
complexe métasédimentaire et migmatitique de l’Ubangi - U
Lepersonne, 1974
Unité très mal connu, cartographiè par Lepersonne en continuité de roches similaires en Centrafrique
et Congo Brazaville.
Sous-division : aucune
Supergroupe de la Ruzizi – SG-RU
Rusizien –R
Originally defined in the eastern DRC (Kivu province), its existence in Rwanda and Burundi as
basement to the Mesoproterozoic Burundian belt was postulated on the basis of gneisses and
micaschists in areas such as the Butare complex and a few Palaeoproterozoic U/Pb ages in the latter
(2063 Ma and 1920 Ma – Cahen et al., 1984; Ledent, 1979; Gérards, 1969). The metamorphic rocks
actually turned out to be (dominantly?) higher-grade equivalents of Mesoproterozoic sediments, but
the radiometric age and aeromagnetic data suggest that a Palaeoproterozoic basement is
subcropping.
As there is no real Rusizian type-area and its original definition was based on rocks that later turned
out to be Mesoproterozoic in age, the existence of the Rusizian has been questioned by some
authors (Lavreau, 1985; Theunissen, 1989). The difficulty of identifying the Rusizian in the Kivu region
is illustrated by the geological map of the DRC (Lepersonne, 1974), where large zones of
undifferentiated Kibaran/Rusizian units are reported between Masisi (square degree S28/2) and
Lubero (square degree S29/1).
Whatever the case, logic demands that the Mesoproterozoic Kibara and Burundian belts evolved on
an older basement. In view of the observed structures, which call for extensive reactivation of this
basement, it is highly unlikely that rigid, cratonised, Archaean units are responsible. Consequently,
one has to postulate the existence of a Palaeoproterozoic basement, which likely corresponds to a
collisional belt between the Archaean domain of NE DRC and the Tanzania craton and would link up
to the south with the peripheral accretionary Ubendian orogen.
The Rusizian belt is thus considered as the NW extension of the Ubendian (or Ubende) shear belt
occurring in western Tanzania, (Cahen, 1954; Cahen and Lepersonne, 1967) and is characterized by a
poor level of knowledge.
.
The variable lithologic compositions include metasedimentary rocks (micaschists, phyllites,
quartzites...), amphibolites, granites, gneisses and migmatites. Although greenstones are locally
reported, greenstone belts as such are not documented.
Sous-divisions:
Speculative correlations between various regions of the DRC (N Katanga, Kivu and Maniema) give the
following general distribution of rock types (Cahen & Lepersonne, 1967; Lepersonne, 1974):
southern Kivu (DRC) and (NE?) Burundi:
migmatitic gneisses, micaschists, amphibolites, coarse-grained quartzites, metamorphosed
limestones and dolomites;
northern Katanga and southern Maniema (DRC):
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Upper beds
Various phyllitic schists, quartzites (locally with lateral transitions to micaschists),
amphibole-schists, amphibolites and metamorphic quartzites.
Phyllitic conglomerates (occasionally including carbonate pebbles, locally with lateral
transitions to biotite-schists containing elongate marble lenses), amphibole-schists
and amphibolites.
Lower beds
Mica-rich, often graphite-bearing, phyllitic schists, containing lenses and beds of finegrained marbles
Quartzites, arkoses and dark-coloured phyllitic schists
Schists, often graphitic, quartzitic schists and quartzites
Higher-grade and retrograde (?) equivalents of the Lower Beds comprise sericiteschists, chlorite-schists, amphibole-schists, micaschists, amphibolites and migmatitic
gneisses
Complexe volcano-plutonique acide des Marungu – Cp - MA
Rhyolites des Marungu et « lower plateau series » - ρ , Lps
The cratonic Bangweulu Block (Andersen and Unrug, 1984), a segment of the Ubende belt exposed
in northeastern Katanga, northeastern Zambia and western Tanzania, includes possible Archaean
segments assembled in a Palaeoproterozoic (2.5-1.6 Ga) structural setting. This assemblage is
composed by schists, gneisses and by late Palaeoproterozoic (c. 1.8 Ga) felsic metavolcanics
intruded by cogenetic granitoids, exposed in Katanga in the northernmost part of the Bangweulu
Block in the Marungu plateau (Kabengele et al., 1991) and also known across the border in western
Tanzania as the Kate-Kipili volcano-plutonic complex (Lenoir et al., 1993).
Sous-divisions: aucune
MÉSOPROTÉROZOIQUE
Supergroupe de la Liki-Bemba – SG-LB
 Liki-Bembien – LB
Lepersonne, 1974
Unité cartographiè par Lepersonne 1974, de position stratigraphique discutable puisque inconnue
en tant que Mésoprotérozoique dans les pays avoisinants (Centrafrique, Congo Brazzaville), ou des
unités en continuité sont répertoriées comme appartenant au Néoprotérozoiques (Lindien,
Ubangien).
Pourrait être revu en tant que Néoprotérozoique.
Sous-divisions :
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Série supérieur
Série inférieur
Supergroupe des Monts Kibara – SG-KB
Kibarien – Kb
Laghmouch et al, 2012, Fernandez-Alonso et al, 2012, Cahen, L., Lepersonne, J. 1967, Kokonyangui,
2004, 2005, 2007
The Kibara belt was defined in the type-region of the Kibara Mountains of southeastern DRC . It
extends NE-SW over a distance of 750-800 km from Kalemie on Lake Tanganyika in the north to the
Nzilo gorges in the Kolwezi area (Katanga province). It is bordered to the west by the Kasai domain of
the Congo craton .Part of the western margin is covered by Neoproterozoic sediments of the MbujiMayi. The eastern margin of the Kibara belt corresponds to border faults of the Neoproterozoic
Kundelungu aulacogen, to which it may form (part of) the basement; the actual eastward extent of
the belt underneath the Kundelungu sediments remains unknown. In the north, Kibaran sediments
are covered in places by sediments of the continental “Karoo cycle”, mapped as both CarboniferousPermian and Triassic-Jurassic
Sous-divisions:
The Mesoproterozoic stratigraphy of the KIB can be subdivided into 4 lithostratigraphic units. They
are from oldest to youngest: the Kiaora Group, the Nzilo (or Lufira) Group, the Mount Hakansson
Group and the Lubudi Group.
The Kiaora Group is dominantly consisted of (quartzo-) phyllites and schists, with quartzitic horizons
and with rhyolites at the top (K1a of Cahen & Lepersonne, 1967).
The(Lufira) Nzilo group is dominantly quartzitic, with locally (quartzo-)phyllitic levels and lava’s on
top. (K1b, K2 of Cahen & Lepersonne, 1967)
The Mount Hakanssson Group consists of dark-coloured slates and quartzites, with conglomerates at
the base. (K2b, K3, K4a of Cahen & Lepersonne, 1967)
The Lubudi Group consists of dark-coloured arkoses and conglomerate lenses, black graphitic shale
with some sandstone levels and an upper part consisting of limestones and dolomites, often silicified
with stromatolites (K4b, K5 of Cahen & Lepersonne, 1967)
The topmost carbonate - stromatholites level (K5) is probably part of the lowermost Neoproterozoic
Mbudji-Mai units as stromatholites have not been described in the Mesoproterozoic in the DRC.
Magmatisme:
Granites : 1370 – 1380 Ma
Granites – pegamtites à étain : +/- 1000 Ma
Supergroupe de la Bilati-Luhule
 fromations de la Bilati – Bi
 formations de la Luhule – Mobisio – LM
the Luhule-Mobisio and Bilati units, already identified by Lepersonne (1974) in northernmost Kivu,
and considered as a possible Mesoproterozoic formation has to be pointed out. The age of these
series outcropping in a restricted areas is poorly constrained. Lonchampt, a BRGM geologist (BRGM,
1972) considered the Luhule-Mobisio unit as situated at a lithostratigraphic level between a locally
defined “Middle Burundian” and a “Middle Lindian” tillite, i.e. as “Upper Burundian”. Moreover, as
above-mentioned, work of the French BRGM performed in the seventies has led to some
reconsiderations of the lithostratigraphy. In the absence of any geochronological data, the age of the
Luhule-Mobisio could as well be Palaeoproterozoic (Lavreau, pers. comm).
Supergroupe du Kivu
 Burundien – B
Badosa, 1996, Villeneuve, 1978, Villeneuve, 1987, Fernandez-ALonso et al, 2012, Tack, 2010,
Lepersonne, 1974
Sous-divisions :
Les travaux de Villeneuve (1977, 1978), dans la région de Bukavu (Kivu), lui ont permis de définir
deux unités lithostratigraphiques, séparées par une discordance ou hiatus sédimentaire, dans le
« Burundien » de cette région. De haut en bas :
•
•
Groupe de Nya-Ngezie
o Fromation de Mughera
o Formation de la Mukubio
o Formation du Bangwe
Groupe de Bugarama
o
o
o
Formation de Mushenie
Formation de Kamanyola
Formation de Kashenie
Cependant, des travaux plus récents de Villeneuve (2004, 2006) sur le Kivu et le Maniéma, lui font
définir trois groupes « Burundiens », séparés par des discordances tectoniques et/ou hiatus
stratigraphiques. De haut en bas :
•
•
•
Groupe de Nya-Ngezie (plus jeune que 1200Ma ; intrudé par des granites et pegmatises à
étain ; 986Ma)
o Fromation de Mughera
o Formation de la Mukubio
o Formation du Bangwe
Groupe du Burundien supérieur (intrudé par les granites 1380Ma)
o Sans non ni sous divisions formelles
Groupe du Burundien inférieur (= Groupe de Bugarama de 1978 ? ; >1600Ma)
o
o
o
Formation de Mushenie
Formation de Kamanyola
Formation de Kashenie
Le Groupe de Nya-Ngezie se corrèle avec la partie supérieure des formations « Burundiennes » au
Rwanda, Burundi, redéfinies en tant que Supergroupe de l’Akanyaru - Groupe de Cyohoha, Groupe
de Rugezi -(Baudet, 1987, Fernandez-Alonso, 2012). Le granite et pegmatites à étain (type G4) datés
à 986Ma, (Tack, 2010) sont intrudés jusqu’à ces niveaux stratigraphiques.
Le Groupe du Burundien supérieur se corrèle avec la partie inférieure des formations
« Burundiennes » au Rwanda, Burundi, redéfinies en tant que Supergroupe de l’Akanyaru - groupe de
Gikoro, groupe de Pindura – (Baudet, 1987, Fernandez-Alonso, 2012). Ces séquences sont intrudé par
les venues des granites de type G1-G3, datés à 1375 Ma (Tack, 2010)
La position stratigraphique du Groupe de Bugarama est problématique : soit « substratum » d’âge
non défini mais probablement Paleoprotérozoique en similitude avec le Rwanda, Burundi; soit la
partie inférieure de la séquence du « Burundien Supérieur », partie non observée au Rwanda,
Burundi.
Au Maniéma, plusieurs géologues de l’UNILU ont travaillé sous la direction de A. H. Kampunzu et R.T.
Lubala dans le cadre de leur thèse de Licence. Les travaux de Badosa et de ses collègues entre Kalima
et Shabunda, dans la partie cartographiée comme « Ruzizien » par Lepersonne, 1974, font conclure
ces auteurs qu’ils sont en fait dans des formations « Burundiennes ». Ils sont amenés à définir ces unités
comme suite :
•
Groupe du Maniéma
o Formation de Mukombe :
Méta-arkoses en bancs très durs, à cassure conchoïdale, à texture massive et à
grains moyens avec du ciment siliceux. Puissance 600 à 800m.
o Formation de Ngongomeka :
Métabasites noire à gris sombre ou noir verdâtre se débitant en bancs subhorizontaux. Puissance 1000 à 1500m.
o Formation de Lubile :
Grès quartzitiques gris sombre avec alternance des niveaux noir-bleuâtre et brun
violacé (bariolé). Puissance 1000 à1800m.
Magmatisme : Ces trois formations ci-haut citées sont intrudé par les massifs granitiques et
leur cortège filonien d’âges Mésoprotérozoïques.
La corrélation avec les travaux de Villeneuve au Kivu, et ceux de Baudet, Fernandez-Alonso, Tack au
Rwanda, Burundi reste spéculative.
•
Si on se base sur la carte de Lepersonne (1974), il est certain que les unités cartographiées
comme « Burundien » au Kivu, doivent se corréler avec le Supergroupe de l’Akanyaru, puisqu’ils
sont en continuité cartographique de ce dernier.
•
La réinterprétation de la géologie régionale du Kivu – Maniéma par Villeneuve (2004), place les
unités décrites par Badosa et collègues dans le Groupe du Burundien supérieur (sillons plissés du
Burundien supérieur), ce qui les corrèlerait avec les groupes de Gikoro et Pindura ; les séquences
inférieures du Supergroupe de l’Akanyaru.
NÉOPROTÉROZOIQUE
Supergroupe du Ouest-Congo – SG-WC
 Ouest-Congolien – I, mp, sc, sh, ti, S
 Mayombien- M
 Zadinien – Z
Tack et al, 2001, Baudet et al, 2013
The type cross-section of the West Congo belt illustrates a general decrease in deformation and
regional metamorphism from west to east. To the west, in the more internal Pan-African thrust and
fold belt, the east-verging, oldest c. 2.1 Ga Kimezian Supergroup (polycyclic Palaeoproterozoic
basement) is thrust onto the Zadinian Group, itself in places thrust onto the Mayumbian Group,
which finally comes into contact with the youngest West Congolian Group
Sous-divisions:
The recently (Tack et al., 2001) revised lithostratigraphic column of the West Congo Supergroup
includes, from oldest to youngest, the Zadinian, Mayumbian and West Congolian Groups. Baudet et
al, 2013, on stratigraphic grounds, introduced a new terminology: resp. from oldest to youngest:
•
•
•
Groupe de Matadi
Groupe de Tschéla (ouest) / Groupe de Seke-Banza (est)
Groupe des Cataractes
o Sous-groupe de la Mpioka
o Sous-groupe de Lukala
o Sous-groupe du Haut-Shiloango
o Sous-groupe du Sansikwa
The topmost unit of the former West Congo group, i.e. the Inkisi subgroup, is postulated by Baudet
et al, (2013), to be post Precambrian, in line with equivalent postulates for the topmost units of the
Lindi and Katanga Supergroups (Kadima et al, 2011, Tait et al, 2011). This unit is a typical ‘redbeds’
arkose, which is characterized by a relative important thickness, red beds, and a series of sedimentay
features typical of a rapidly deposited shallow-water deltaic siliciclastic deposits.
Inkisi (Super) Group
Cataractes
Group
Seke-Banza
Tshela
Group
Matadi
Group
Supergroupe de la Lindi – SG-LI
Lindien – L, a, l, tillite, it
Ubangien – a,l
Verbeek, 1970, Kadima et al, 2011, Tait et al, 2011
The Neoproterozoic Lindian Supergroup (Verbeek, 1970) exposed in N DRC (essentially in Eastern
Province of DRC), at the southern edge of the Pan-African Ubanguide fold belt consists of a
sedimentary sequence with a thickness of more than 2,500 m, which was considered as alleged
foreland deposits of this orogen. The Ubangian is the local name for the extension of this unit in
Equator Province of DRC. The prolongation of these sedimentary series to the north, in CAR, via the
N-S-trending Fouroumbala basin, includes a series of units with local names gathered by Poidevin
(1985) under the names of Middle Chinko–Morkia-Rumu and Fouroumbala Formations.
Sous-divisions:
According to the detailed study of Verbeek (1970), the Lindian Supergroup has been subdivided into
three main units, which are from top to bottom, the Aruwimi, Lokoma and Ituri Groups .
Verbeek (1970)
BRGM
(1980-1982)
Aruwimi Group
Average thickness
Yambuya Formation
not mapped
± 1.200 m
L8
± 400 m
L7
± 150 m
S
Banalia Arkoses *
(not anymore part of Aruwimi but separate
(Super)Group
L i
d i
Malili Formation
Alolo Shales
Galamboge Quartzites = Gemena Quartzite
(Ubangian)
Lokoma Group
Bombua Formation
Kole Shales
L6
± 100 m
L5
from 250 to 500 m
L4
50 - 300 m
LT
50 m (lenticular)
Asoso Shales
L3
50 m
Lenda Limestones
L2
50 - 100 m
Penge Quartzites and Arkoses
L1
± 20 m
Opienge-Bomili-Bafwabato Conglomerate
Mamungi Shales
=Wanie-Rukula Limestones
=Opienge Dolostones
Panga Formation
Bobwamboli Arkoses
= Avakubi Sandstones and Conglomerates
= Lundutuda Sandstones and Conglomerates
Akwokwo Tillite
Ituri Group
The Banalia Arkoses, which is characterized by a relative important thickness (c. 1200 m), red beds,
and a series of sedimentary features typical of a rapidly deposited shallow-water deltaic siliciclastic
deposits, laid down under a regular subsidence of the basin, and resulting from a granitic source, are
postulated to be of Post precambrian age (Kadima et al, 2011, Tait et al, 2011) ..
Supergroupe de la Mbuji-Mayi – SG-MB
 Bushimay et Luamba – b0, b1, b2, Lu
The Neoproterozoic Mbuji-Mayi (Bushimay) Supergroup (Raucq, 1957) crops out in the type area of
eastern Kasai and in northwestern Katanga. In Katanga, the Supergroup rests unconformably upon
the Mesoproterozoic Kibaran belt, while in southern Kasai, it unconformably overlies the Archaean
Kasai craton. In the north, the supergroup is overlain by Mesozoic sedimentary rocks belonging to
the Congo Basin (“Cuvette Centrale”). The Roan Supergroup of Katanga, forming the lower part of
the Katangan System, is considered as the stratigraphical equivalent of the Mbuji-Mayi Supergroup
(Raucq, 1970; Cahen, 1982; Baudet, 1987). The poorly studied Luamba unit, in western Katanga,
forms a narrow zone which is considered as correlative with the Mbuji-Mayi Supergroup
(Lepersonne, 1974)
Sous-divisions:
According to Raucq (1957) and Lepersonne (1973), the Supergroup is subdivided into, from bottom
to top B0, B1, B2. In Kasai, Baudet 1987; Raucq and Baudet, 1991 identified B1 and B2 as resp. B I
and B II.
•
B0 Group (1000 – 2000 m): mainly constituted of arkoses, quartzites, red shales and
conglomerates. This Group, absent in Kasai, occurs only in the southern part of the zone
located in Katanga, along the Kibaran belt. It is characterized by its local distribution and is
presumably older than the Roan group of Katanga.
•
B1 (B I) Group (c. 1000 m): subdivided into a series of subunits (B1a–B1e), which can be
summarized as follow:
 B1a–b: displaying lateral variations of facies, from calcschists to
conglomerates including pebbles from the basement. In Katanga, no
distinction is made between this unit and the B0 Group;
 B1c–d: whitish quartzites and shales;
 B1e: shales and calcschists;
•
B2 (B II) Group (800 – 1000 m): limestones (locally silicified, cherty, oolitic, or with
stromatolites), dolomites.
Magmatisme:
The Mbuji-Mayi Supergroup includes amygdaloidal basaltic pillow lavas. Their relationship with the
Supergroup is still matter of discussion. The coincident ages obtained from samples of different lavas
(950 Ma ± 20 Ma; K-Ar age determination; Cahen, 1982) suggest a single volcanic event. Many
dolerite dykes cutting the Supergroup are considered as the feeder systems of the lavas.
(Super)Groupe de la Lubudi – SG-LU
non cartographié par Lepersonne, 1974
Le groupe de Lubudi est l’unité supérieure de la pile sédimentaire du Supergroupe des Monts Kibara,
et consiste en sa partie inférieur d’arkoses et conglomérats sombres, des shales noirs graphitiques et
quelques niveaux de grés ; ainsi qu’une partie supérieur composée de calcaires et dolomies, silicifiés
et des stromatholites.
Nulle part ailleurs en RDC, des stromatholites ont été décrit faisant part du Mésoprotérozoique .
D’autre part, des unités géographiquement avoisinantes du Néoprotérozoique (Mbuji-Mai)
contiennent typiquement ce genre de formations organiques. Il y a donc lieu à supposer que les
géologues, travaillant dans la région, ont mal attribué ce niveau au Supergroupe Mésoprotérozoique
des Monts Kibara.
Supergroupe de l’Itombwe – SG-IT
non cartographié par Lepersonne, 1974 ; considéré Burundien - B
Villeneuve, 1977, 1987 and Walemba et al, 2005
The Itombwe and Irumu troughs
The previously called “Itombwe Syncline” or “Itombwe Synclinorium”, first described in 1946, has
been studied by several geologists, who have established different lithostratigraphic columns for this
geological unit (Lohest, 1946, 1964; Peeters, 1955, 1956; Villeneuve, 1973, 1976, 1978, 1983, 1985;
Waleffe, 1988).
Sous-divisions:
According to Walemba et al, 2005, the Itombwe Supergroup consists of an Upper Kadubu group and
a Lower Kadubu group, separated by a tectonic contact.
Villeneuve 1987 also describes these upper and lower Kadubu “sections” but postulates that both
might be equivalent stratigraphic levels. He divides the Itombwe Supergroup into into a lower NyaKasiba Group (thickness ~ 1000 to 1500m) and an upper Tshibangu Group (thickness ~ 2000 m).
Supergroupe du Katanga  Katangien - K
Cailteux et al, 2008, Kampunzu et al, 2009
Sous-divisions
The Katangan sedimentary rock succession totals 5-10km in thickness and is divided into three major
lithostratigraphical units (François,1974, 1995). From bottom to top, these units are the Roan
(codeR), Nguba (code Ng, formerly Lower Kundelungu) and Kundelungu (code Ku, formerly Upper
Kundelungu) Groups.
PHANÉROZOIQUE
(Super)Groupe de l’Inkisi
Inkisi – I
(Super)Groupe de Banalia
non cartographié par Lepersonne, 1974 ; partie supérieure de Aruwimi - a
(Super)Groupe des Biano
non cartographié par Lepersonne, 1974 ; partie supérieure de Kundelungu supérieur –
K3
post-précambrien, pré-Karoo
Kanda-Nkula et al, 2011, Delpomdor et al, 2011, Tait et al, 2011
Neoproterozoic tabular sedimentary sequences were largely preserved and define respectively the
West Congo and Katanga Supergroups. The uppermost unit of these Supergroups consists of a ca
1000m thick Redbed-facies sequence, respectively the “Inkisi” and “Plateaux (also known as KilunguLupili or Biano)” Subgroups. Other similar Neoproterozoic sequences are known in intracratonic
aulacogenes in and/or around the Congo river basin, where they define distinct Supergroups (e.g. the
Mbuji-Mayi Supergroup in the DRC Kasai region). The most prominent is the Lindi/Ubangi
Supergroup exposed to the N and NE of the CRB. Its uppermost unit (the “Banalia Arkoses”) is also a
ca. 1000m thick Redbed sequence.
It was shown that these Redbeds overlie unconformably the folded Neoproterozoic sequences of the
Pan-African West Congo and Katanga belts and are thus post ca. 550Ma (paroxysm of Pan African
orogeny). Therefore, they can no longer be considered as Precambrian but are Phanerozoic in age.
The Redbeds are themselves overlain by the ca. 320Ma Karoo tillite (base of the Karoo Supergroup).
The Redbeds of the CRB are characteristic of lacustrine and fluvio-deltaic (semi)arid palaeoenvironments, in contact with atmospheric oxygen as indicated by their colour due to iron
oxides/hydroxides coating around detrital grains, but their palaeo-depositional history is still poorly
constrained.
Sous-divisions: non connues
Supergroupe du Karoo – SG-K
 Carbonifère supérieur , Permien inférieur, : série de la lukuga - pc
 Triasique et ( ?) Liasique : série de la haute Lueki – t
Delvaux, 1991
The Karoo deposits (encompassing Upper Carboniferous, Permo-Triassic and Lower Jurassic) occur
either as part of the sedimentary pile of the “Cuvette Centrale”, or as infilling of rift basins (e.g.
Lukuga and Luena basins).
Sous-divisions:
The Karoo deposits include the Permo-Carboniferous Lukuga series (siliciclastic rocks with minor coal
seams; Cahen and Lepersonne, 1978) and the Triassic red facies rocks of the Haute Lueki series.
Lower Karoo sediments are of fluvial/lacustrine origin, while Middle and Upper Karoo are essentially
of fluvial origin
(Super)Groupe de Kisangani - (S)G-KIS
 Jurassique supérieur post Oxfordien : série de Stanleyville - J
Lepersonne, 1974, 1977
Sous-divisions : alternances d’unités lithologiques sans division formelle :
Dans la région comprise entre de Kisangani au nord et Lubefu, au sud, de haut en bas
Grès, argillites de la Lilo
Argillites de la Riki
Grès , argillites sableuses, intercalations chistes bitumineux
Argillites
Argillites et schistes bitumineux de l’Usengwwe
Argilites calcaires
Argillites et schistes bitumineux de la Loso
Argillites, grès
Schistes bitumineux de Minjaro
Argillites
Argillites, grès , grès conglomératiques, conglomérats avec passées bitumineuses.
-
Supergroupe de la Sankuru – SG-SAN




Crétacique indifférencié, principalement inférieur - c
Wealdien : série de la Loia – c1
Albien – Aptien : série de Bokungu – c2
Crétacique supra-Cénomanien et ( ?) Cénomanien : série du Kwango, couches de
Boende – c3
Lepersonne, 1974, Lepersonne, 1977, Kadima, 2011
Lepersonne (1977) has proposed the following succession for the Mesozoic formations, from top
to bottom:
•
•
•
Kwango Group
Bokungu Group
Loia Group
(Cenomanian –C3)
(Albian -? Lower Cenomanian – C2)
(Albian-Aptian – C1)
Supergroupe de la Luki – SG-LU




Crétacique inférieur continental : « grès sublittoraux » - c1
Albien – Aptien continental : Mavuma supérieur – c2
Aptien marin : Mavuma inférieur – c2
Maestrichtien, Campanien, Santonien, Coniacien, Turonien – c3
Cahen 1954, Lepersonne, 1974, Kadima, 2011
•
•
•
Formation de Bulu-Zambi – C3
Formation de Mavuma – C2
Formation de Lukunga – C1
Supergroupe du Kalahari-SG-KAL
 Paléogène : série des « grès polymorphes » (« Kalahari » inférieur) – tt
 Néogène : série des sables ocre (« Kalahari » supérieur) – tt
 Miocène inférieur, Eocène, Paléocène – e, mi
The Cenozoic to Recent formations overlying the “Cuvette Centrale” are continental in origin and
comprise (from top to bottom):
1. The fine Neogene yellow (ocre) sands, relating to the Upper Kalahari formations, form
discontinuous lenses of 30 to 40m thickness which represent remnants of a formerly continuous
blanket. They rest on a Mid-Tertiary peneplain;
2. The Paleogene “Grès polymorphs”: a series of sands and soft sandstones exposed along
discontinuous lenses. The series is related to the Lower Kalahari and its thickness ranges, e.g. in
Kasaï between 10 and 20m (Delhal et al., 1966, in Carte géologique à l 'échelle 1/200,000, feuille
de Dibaya).
Supergroupe de la Cuvette centrale – SG-CC
 Pléistocène , Pliocène : alluvions, éluvions et colluvions – pp
Lepersonne, 1974
(Cahen, 1954); The Lower Pleistocene to Pliocene sediments: more or less argillaceous sands with
conglomerates at the basis cover the late-Tertiary plains. The yellow sands are recognized to
originate from the Neogene sand formations, the red sands relate to the Cretaceous formations. The
thickness of the Lower Pleistocene to Pliocene cover is reported to range between 25 and 40m
Lepersonne, 1974: couches de Yagambi, de Salonga, Lodja
Formations du Rift
Miocène : fossé tectonique centre africain – ml
Pléistocène , Pliocène : alluvions, éluvions et colluvions – pp
Kampunzu et al., 1998b, De Paepe and Fernandez-Alonso, 1981, Tack and De Paepe, 1983; Tack et
al., 1987
The Cenozoic volcanic activity is contained in three volcanic provinces in Kivu: the Virunga,
Bukavu and Mwenga-Kamituga Volcanic Provinces.
The Virunga Province is characterized by two major volcanic episodes:
1. The Recent to Present (Pliocene-Pleistocene) episode, including peralkaline potassic volcanics
(silica undersaturated lavas: nephelinites, melilites and leucitites, potassic basanites,
mugearites,...); outpoured from eight major volcanoes;
2. The older initial Virunga episode (Miocene) including basalts with tholeiitic affinities at the base,
overlain by Na-alkaline lavas (basanites, hawaiites, ...).
The Bukavu and Mwenga-Kamituga Provinces, also extending in Rwanda and Burundi display:
1. Tholeiitic to transitional basalts during the pre-rift stage;
2. Na-alkaline lavas during the initial stage of downwarping (rift individualisation);
3. Transitional volcanics during the graben stage.
It is suggested (Kampunzu et al., 1998b; Pasteels, 1989) that the volcanism associated with the
Western Rift began c. 11 Ma ago in the Virunga region and c. 10 Ma ago in the Bukavu region. The
age of the earliest extrusive rocks recorded in the Mwenga-Kamituga region, not well constrained,
could be close to 6 Ma.
(Super)Groupe de Quelo – (S)G-QU
Pléistocène, Pliocène et ( ?) Miocène supérieur : « série des Cirques », Quelo – ppm
Lepersonne, 1974
Sous-division :
• Quelo supérieur - « Série des Cirques » pleistocène ?
• Quelo inférieur : pliocène – miocène supérieur
Alluvions et sédiments subaériens - Ho
 Holocène : alluvions modernes - Ho
Lepersonne, 1974
Alluvions anciennes, modernes, terrasses fluviatiles, produits d’altération, plages anciennes, sables
d’estuaire.