Sedimentology and Sequence Stratigraphy of the Late Precambrian Carbonates of the Mbuji-Mayi Supergroup in the Sankuru-Mbuji-Mayi-Lomami- Lovoy Basin (Democratic Republic of the Congo) - Geology and Resource Potential of the Congo Basin - page 59

Table 4.1 Simplified stratigraphy of the Mbuji-Mayi Supergroup in the north Sankuru-Mbuji-Mayi-Lomami-Lovoy Basin, Kasai-Oriental
region, DRC (after Raucq 1970 )
Mbuji-Mayi Supergroup, DRC
Group Subgroup Formation Lithostratigraphy

948 20 Ma (Cahen et al. 1974, 1984 )

BIIe BIIe 5 Grey limestones with stromatolites (17.5 m)

BIIe 4 Brecciated grey limestones, stromatolites (24 m)

BIIe 3 Pink limestones (11 m)

BIIe 2 Grey limestones, grey to pink dolostones (15 m)

BIIe 1 Pink to grey shaly to calcareous dolostones (13.5 m)

BIId BIId 3 Grey cherty dolostones with cherts, pink shaly dolostones (343 m)

BIId 2 Grey dolostones, shaly dolostones and dolomitic limestones (42 m)

BIId 1 Shales with cherts (15 m)

BIIc BIIc 8 Dark shales, green to purple shaly dolostones (24 m)

BIIc 7 Grey dolostones with stromatolites (5 m)

BII BIIc 6 Dark shales, grey shaly dolostones (27 m)

BIIc 5 Grey dolostones with stromatolites (25 m)

BIIc 4 Dark shales, grey shaly dolostones (12.5 m)

BIIc 3 Grey dolostones with stromatolites (88 m)

BIIc 2 Dark shales, grey shaly dolostones (21 m)

BIIc 1 Grey dolostones with stromatolites (89 m)

810 Ma (Delpomdor et al. 2013a )
BIIb BIIb 5 Dark cherty dolostone, shaly dolostones (25 m)

BIIb 4 Shaly calcareous dolostones (23 m)

BIIb 3 Polygenetic conglomerates (19 m)

BIIb 2 Shaly dolostones and calcareous dolostones, often brecciated (39 m)

BIIb 1 Grey cherty dolostones (9 m)

BIIa Grey dolostones with stromatolites (105 m)

BIe BIe 2 Grey-pink feldspathic psammites (1 m), grey shaly dolostones (26.5 m)

BIe 1 Grey to pink dolostones with galena (25.5 m)

888.2 8.8 Ma (Delpomdor et al. 2013a )

1040-1065 Ma (Cahen 1954 ; Holmes and Cahen 1955 ; Raucq 1957 )
(BIE)

BIE 2 Locally visible in the Kafuku area—red shales, shaly psammites, grey calcareous dolostones (28 m)

BIE 1 Locally visible in the Kafuku area—pink to brown shales, grey dolostones (31.5 m)

BI BId BId 2 Quartzites (308 m)

BId 1 Red sandy psammites, sometimes dolomitic

BIc BIc 2 Red shales and shaly psammites (180 m)

BIc 1 Conglomerates

BIb Basal conglomerate, alternations of sandstones and conglomerates (17 m)

BIa Only visible in south SBLL basin—shales and quartzites (500 to 1,500 m)

1152 15 Ma (Delhal et al. 1989 )

1155 15 Ma (Delhal et al. 1966 )

1174 22 Ma (Delpomdor et al. 2013a )
1310 25 Ma (Cahen et al. 1984 )

BIIe (Formini`re and samples; Fig. 4.2 )

Subgroups were studied from the collection of the RMCA.

stop 628 and outcrop samples. Our carbonate microfacies are named

after the depositional fabric according to the classification
of carbonate rocks (Dunham 1962 ; Embry and Klovan
1972 ; Sibley and Gregg 1987 ) and take account of sedimen-
tary structures and/or fossils, e.g. wavy laminated
dolomudstones, oolitic grainstones, and stromatolites. Each
sample, in thin section, was etched with Alizarine red S and
potassium ferricyanide for recognition of carbonate minerals
(for more details, see Delpomdor and Pr ´ at 2012 ).

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4.4.2 Microfacies Analysis

Microfacies descriptions are based on the recognition of
grain and sediment types, sedimentary structures and
textures, using 788 selected thin sections from drillcores