COMPARATIVE BASIN STRATIGRAPHY CONGO KWANZA - NAMIBE

RELATIVE CHANGE OF N Y N Y

M BIOSTRATIGRAPHY BIOSTRATIGRAPHY O O S M M M

I COASTAL ONLAP S S I

U (C0NGO)

(KWANZA) E T E T T E T N N I I T G A A

A TECTONIC

N I R I A E M R E M E U PHASE T Y S CONGO BASIN KWANZA BASIN NAMIBE BASIN R G R

R S S S G S S S

S C IC C I IC

E I A O A N N O N N O O O O

F T F T K H H LANDWARD BASINWARD N T K T A N N N L E A E 1.0 0.5 0 P B L B 0 W E W E P W E HOLOCENE UNIT QUATERNARY MILAZZIAN S PLEISTOCENE QUELO MUSSEQUES Silt, ferruginous and clay. Several unconformi-

SICILIAN E Sand, silt, ferruginous SSt and clay. Several EMILIAN U unconformities are noted with associated ties are likely with associated sand. Continen- 7 E N BTS 10 CALABRIAN Q tal depositional environment. BTS 10 E U 1.65 sand development. Continental depositional 5 C PIACENZIAN 3.5 I R TS 10 IO environment. TS 10 L UNNAMED LUANDA Luanda is likely to extend from BURDIGALIAN to PLIOCE- P ZANCIEAN C WESTWARD L 5.2 (CIRQUES EQ.) NE. Calcareous and argillaceous sands. SUBSIDENCE MESSINIAN Litoral depositional environment. 5 6.3 Delta sands, interbedded siltstone and PHASE P

R EROSION E claystone. Good delta sand reservoirs are TS 9 OR H

P TS 9 TORTONIAN NON DEPOSITION associated with unconformities. Inner neritic EROSION

P OR A depositional environment. NON DEPOSITION Sands with clay and silt. E 10 U S 10.2 TS 8 BTS 6/7 (PHASE VIII)

N BTS 6/7 E TS 8 10 10.5 E E Variable lithology from fluvial sands to L E SERRAVALLIAN G TS 7 insterlayers of sand and crinoidal l.st to TS 7 N D

I marl-shale-silt. Sand layers near the

O 15 E 15 M CACUACO unconformities are likely reservoir poten- 15.2 VIII E C LANGHIAN tial. Litoral, circalitoral depositional envi- 16.2 TS 6 TS 6 Variable lithology in interbedded shales and QUINDABELE O N

O ronment.

I silts. BTS 5/6 BURDIGALIAN B Thin turbiditic reservoirs are noted near BTS 5/6 Variable lithology from fluvial sands to M TS 5 unconformity levels. Inner neritic depositional BOM JESUS crinoidal l.st and sands to marl-shale-silt. TS 5 Shale, silt, marl. M 20 20 environment. Reservoirs are likely. E R 20 E UNIT

W Notable volcanism in deep basin 21 O 6 FUNDA ANGONDO L TS 4 BTS 4 TS 4 BTS 4 AQUITANIAN Variable lithology from fluvio-continental

CATALA

M A L sands to marl-clay-silt to shale and silt 25 TS 3 Sand layers are likely to be present near 25 25.2 TS 3 CALOMBOLOCA unconformities. Reservoirs are likely. QUI F

R

E BTS 2/3 BTS 2/3

E

P CHATTIAN TS 2 Depositional environment range from TS 2 C

P N CHIO Y

I outer platform to bathyal. U Variable lithology in shales, silts, marls and CALOMBOLOCA E 30 R 30 limes. Bathyal - neritic depositional 30

C O P environment. Noted thin turbiditic sands near TS 1 BTS 1 TS 1 BTS 1

O A Z R EROSION the uncoformity. Erosion or not deposition H I E G OR near offshore and onshore. A I RUPELIAN NON DEPOSITION W O

L S O EROSION L

O E 35 R T OR NOT NOT NON DEPOSITION 35 36 RECOGNIZED Sands, silt, shale. RECOGNIZED E

R

E T C E N PRIABONIAN

P

P

U 39.4 VII 40 TI 7 TI 7 BARTONIAN 39.5

E Variable lithology in shales, silts, marls. 40 Reservoirs sands developed near the

E 42 N E unconformities. Crinoidal limestones and L N E sandstones in Ambrizete, member a coastal BTI 6/7

E TI 6 D depositional environment. G 45 I BTI 6/7 AMBRIZETE TI 6 C M LUTENIAN Variable lithology from sands-silt, 45 O Reservoir bearing deltaic channel sands CUNGA O marl-clay-silt to shale-silt. Thin layers of

E development A E limestone. L EQ.) 49 Erosion near offshore. 50 A Pelagic depositional environment. A N 49.5 P 50

E R GRATIDAO D TI 5 BTI 5 YPRESIAN TI 5

W BTI 5 UNIT N O DRIFT L 5 TI 4 BTI 4 PHASE 54 TI 4 BTI 4 Volcanism L A 55 UNNAMED P 55 H

R TI 3 E E THANETIAN TI 3 A (LANDADAN A

P (PHASES IV-VII) Variable lithology having shales, marls and S

P E N U silts. Thin sandy reservoirs are noted near the E unconformities (1). Lithology includes shale, marl and layers 59.5 C BTI 1 60 BTI 1 60.2 RIO DANDE of dolomitic limestone and limestone. 60 O Neritic bathyal depositional environment. TI 2 Moderate source potential. TI 2 E

E R Marine shales, silts, marls. L DANIAN Source potencial is in selective basinal areas. Platform depositional environment. VI W A O P 65 L TI 1 3 TI 1 65 66.5 (POST RIFT) E R 67

P CS 9

U CS 9 70 ALTO MAASTRICHTIAN BCS 8/9 70 TEBA

R BCS 8/9 E W

O SEPULTURES P ) L Llithology includes fluvio-continental

N H 74 sands-silts, interlayers of crinoidal l.st, 75 A A I Variable lithology having shales, marls and marls, shales and siltstone. 75 N E R silts. Bathyal pelagic depositional environ- S P O ment. E U Platform depositional environment. CS 6/8 N CS 6/8 BOLD E CAMPANIAN Very good marine source rocks that are BCS 6/7 BCS 6/7 S regional in extent.

( Good source potencial. Likely reservoirs 80 Marine shales, silts, marls. E R

E are in sands and l.st. Good source is likely. 80 E R W Thin sandy reservoirs near the unconformity.

O UNIT V P L A B P I 4

U 84 R E (IABE EQ.) UNNAMED

P CS 5 P

85 U 85 SANTONIAN CS 5 R

E BCS 4/5 BCS 4/5 NGOLOME W CS 4 L O CS 4 88 U FRIO CONIACIAN L 89 U 2 AZUL CS 3 90 M Reservoirs in (1) Lago sst and (2) Azul sst Lithology includes fluvial sands to marine CS 3 TURONIAN 90 Lithology is variable mixture of silt, shale, BCS 2/3 MORRO L LAGO marls, claystones and siltstones. Good source BCS 2/3 C DA CRUZ 1 CS 2 ITOMBE 92 marl. potential. CS 2 U

O U S 1 Pelagic depositional environment. MESA Reservoirs in (1) Mesa dolomite (2) Vermelha O I CENOMANIAN M Varied lithology from fluvial sands to mari- E sst Lithology is variable mixture of silt, lime 2 BCS 1 P Z 95 and clay. Fluvial to marine transational Cs 1b ZENZA/ ne carbonetes, marls, silts and clay. Poten- BC 1 94 L MUCONGA

CABO LEDO Cs 1b 95 C VERMELHA depositional environment. tial reservoirs are in Cabo Ledo carbona- H 96 SANDSTONE ? ? CS 1 tes. Pelagic depositional environment. ? A Varied lithofacies that grade from sands to carbo- CS 1 ? A 5 MOITA SECA

E R Varied lithofacies grading from continental fluvio- S O nates. Reservoirs in shoal carbonates and porous S 2 QUISSONDE P -alluvial, sabkha, shelf edge to deep marine facies. UP ALUVIAL sandstones are known. The lithofacies from coast E U to offshore are (1) Vermelha-continental, (2) Verme- Cs 1a 5 98

2 Cs 1a Varied lithological sequences 100 PUNJA lha-fluvio/alluvial, (3) Bufalo-marine, (4) Pinda car- Depositional environment varies from fluvio- A

M E bonate platform with high energy oolitic shoals -continental, lagoonal to outer platform. from very coarse sands, sands, 100

R E T 4 E PACASSA MP MUCANZO/ L ALBIAN (Pacassa) and open marine carbonates (Punja), EQ.) CACOBA

D carbonate buildups to deep 4 BC 1 CATUMBELA BC 1

D (5) Moitaseca (bathyal-neritic)-deep marine,

C UNIT

I 1 Good reservoir and source potential.

PINDA VERMELHA-FLUVIO marine marl, shale, silt. M SANDSTONE (6) Pinda sandstones-marine. IV 6 3 DONDO 3 Good reservoir is likely in C 1 Encountered lithologies include sand and silt, CS 1 P I N D LP 1 Good reservoirs same source potential. anhydrite, dolomite, crinoidal l.st, argillaceous carbonate buildups. 105 BUFALO R TUENZA 105 UNNAMED l.st marl and shale. E 3 (PIND A

W Marine depositional environment . VERMELHA Anhydritic, dolomite and sand;subreefal O CONTINENTAL

L 1-Mesa 2-Vermelha carbonates are locally developed in BINGA QUIANGA INHUCA Quianga lagoonal depositional environment. 107.5 MAVUMA 108 PENESALINE-1 Penesaline -1 layers of carbonate clay and anhydritic. ANHYDRITE E R Layers of anydrite, halite and other salts. Wherever MASSIVE SALT Massive salt with diapers penetrated upto Tertiary sedi- 1 UNIT Marine sequence-shale, silt and TRANSITIONAL

R LOEME MASSIVE SALT LOEME 110 P present, acted as inhibitant to upward oil migration. ? ment. Restrictid evaporitic environment. PHASE U sand. 110 POST E APTIAN Restrict evaporitic depositional environment. 2 (PHASE IV) AS 12 PENESALINE 2 Penesaline -2 layers of carbonate, anhydritic, clay. 2

R RIFT C IX E CHELA 1 W Marine transgressive sequence in a transitionalenvironment. A A 3 Marginal marine transgression. W 112 Good porous sandstone with layers of shale limestone. Acted as AS 1 GREY CUVO O Marginal marine transgressive sequence. Layers of sand, O L

pipe rock HC migration. 1 K 13 Shale, silt and sand. 113 ? 1 4 AS silt, claystone and carbonate. Moderate reservoirs. LATE

L VOVO UB TOCA 9/10 U VOVO Lacustrine shales, silts and limestone. Good organic rich 2 shale. Layers are present al places. Lacustrine turbidites ORGANIC CUVO 2 C VII/IX BARREMIAN OB B Recognized unusual massive salt in Maculungo (500m Lacustrine sequence shales and silts 115 BUCOMAZI (Vovo member) developed at places. Good source and reser- AS 3 3 K 15 B 115 s 6/8 thick). Lacustrine sequence-siltstone shale and carbonate. 4 C V/VI with volcanics. Likely source. L LB voir. Lacustrine carbonate mounds (TOCA) ou basement flank in UB. Restrict lagoonal-lacustrine depositional environment. 4 C IV MASSIVE SALT Good source potential. Lacustrine depositional environ- 5 116.5 ment. 6 T K 16 C IV U P L RED CUVO 5 DRIFT PHASE H

HAUTERIVIAN 5 T

A 7

K 17 6 A L ? 120 AS 120 S ERVA 3/5 ? S N Possibly continental red beds with basement 121 E Possibly continental red beds. UNIT E A intraclasts. Poor reservoir and poor source. (PHASE III) I 7 Continental sequence with lacustrine U 6 MACULUNGO Lithology is siltstone, clyst, conglomerate, R

Lithology is siltstone claystone, shale. CUVO M carbonates, volcanoclasts and basement 8 1 influence.

PRESA L 8 P O intraclasts. ? Depositional environment is continental to ? VALANGIAN ? Present in reservoirs and source. 125 lacustrine. K 18 Silts and shales with extensive O C L 7 ? volcanoclasts. 125 III E

N 126 The lower lithological sequence in wells Volcanics are likely. EARLY 128 ? U Maculungo, Calomboloca indicate to be LUCULA Lucula is fluvio-alluvial sands with stringers of clay, lime and basement CALOMBOLOCA Jurassic. 128.5 RYAZANIAN clasts. Good reservoir, Fluvio-continental depositional environment. INITIATION PHASE 130 L QUEMBELE Nacanga is cherty limestone on basement flanks and fractured reservoir, 130 PHASE II NACANGA likely to be a Pre-Neocomian (Jurassic) in lacustrine (?) environment. ? 131 CAMBAMBE . E

T PRE RIFT P B Precambrian granitic and gneissic basement. Precambrian basement inundated by Mesozoic volcanics overlying the PHASE H older than 600 my. The high areas are inundated, hypabyssal dykes and Mesozoic volcanism.

YNOMORPHS A YNOMORPHS Precambrian basement. Pulses of O M OSTRACODS A L sporadically, by hypabyssal dykes or Mesozoic A L Volcanism is estimated to be around 111 MY,

PC - BSMT P S BSMT volcanism is likely in the entire Y + volcanics. Volcanism is estimated to be around 133-135 MY and 164 10 MY. YNOMORPHS OSTRACODS (PHASE I AND II) I

A E A L stratigraphic column. AGE IN MY 130 my. AGE IN MY CONGO OSTRACODS CABIND A P CONGO P

CONGO CALNANINOP L CABIND A M CAL.NANNOPLANK.

BLOCK 2, 3 BLOCK 3,4 ONSHORE, LWR CABINDA MUBAFO (BLOCK 5) CABINDA NAVALHA CONGO, BLOCK 2 AREA A FLAMINGO-1 CEGONHA (BLOCK 6) ONSHORE AREA B, C CABINDA AREA A ONSHORE GAVIÃO ONSHORE CABINDA (BLOCK 6,7) BLOCK 7,8 AMBRIZ-2 (BLOCK 5) WSW ENE NNW SSE WSW ENE WSW ENE

5 MOITA SECA 1 UP 5

UP U UP U 4 A B 4 QUISSONDE CATUMBELA PUNJA VERMELHA 4 FLUVIO/ALLUVIAL MP 1 A M PACASSA PINDA LAGOONAL

MP DONDO MP PUNJA 3 LP M PINDA SANDSTONE 2 LP 3 L TUENZA PACASSA VERMELHA 2 BUFALO CONTINENTAL SHELF-EDGE 6 NOT TO SCALE PACASSA MUCANZO/CACOBA LP ZONE ARD PW lain by U der t ridge MAVUMA Un men L ase DOLOMITES BINGA/QUIANGA D ZONE b AR by E PW rlain ON U nde nt ridge P Z y Schematic view of Albian Platfotm in Namibe Basin. Shelf-edge carbonate buildups are anticipated. U me WAR in b e ase ZONE UP rla idg No exploration well in the basin. OPE b RD y nde nt r LF-SL NOT TO SCALE WA in b U me SHE UP erla ge ase nd nt rid b U eme as NOT TO SCALE PE b -SLO SHELF Schematic view of Albian Platfotm in Congo Basin. Varied lithologies are noted across the basin from onshore to present day shelf-slope. Prominent oolitic carbonate reservoirs in Upper, Middle and Lower Schematic view of Albian Platfotm in Kwanza Basin. Reservoir s (A,B) are in Upper, Middle (Catumbela) Albian are associated with upward zones (or paleo shelf-edge). Chert market beds are noted in Middle and Lower (Tuenza) Albian Carbonates, associated with upwarp zones (or paleo shelf-edge). Pinda. Schematic Albian platform showing varied lithofacies in Congo, Kwanza and Namibe

10E 15E

Biostratigraphy: explanation Biostratigraphy: explanation A Biostratigraphy: explanation EXPLANATION OF TECTONIC PHASE: D N re I ai N B . Z 5S A R C 1. Presalt: Congo Basin 2. Albian - Cenomanian (zonation based on Gofas, 1985) 4. Paleocene - Eocene (zonation based on Gofas, PHASE-I : LANDSCAPE OF EXTREME PENEPLANATION 1985). Cabinda Ostracods by Chevron: 1. Hourcquia africana, 2. Petrobrasia PHASE-II : DOMING AND FLOOD BASALT ERUPTION CONGO Albian: Planktonic Foraminifer: Favusella washitensis; BASIN spp. Benthonic Foraminifer: Trocholina silvai; Veenia spp. (Ostracods); Planktonic: TI 1- Globorotalia trinidadensis/Globigerina DEPOSITED FLUVIO-ALLUVIAL SEDIMENT. 3. Cypridea (Sebastianities), 4. Reconcavona, Nannoconus donatensis (Calcareous Nannoplankton); daubjergensis; TI 2 - Morozovella angulata; TI3 -

5. Paracypridea, 6. Tucanocypris, 7. Metacypris. Globorotalia PHASE-III : RIFTING AND CONTINENTAL EXTENSION. DEPOSITED N Ambris Anomalina berthelini (Benthonlc Foraminifer)

velascoensis; TI 4 - Globorotalia aequa/lensiformis CONTINENTAL AND LACUSTRINE SEDIMENT.

A

Lower Congo Ostracods: Zonation by Grosdidier, E. Luanda

Cenomanian: Dominated by Planktonics. E Benthonic: BTI - 1/3 - Bolivina africana Eponides PHASE-IV : THERMAL SUBSIDENCE, EVAPORITE FORMATION KWANZA Common Occurence is Hedbergellids and Rotaliporids. BASIN

DEPOSITED MARINE DOMINETED SEDIMENT, SEA-LEVEL RISE. C

Lower Congo Calcareous Nannoplankton: Zonation by Sissingh, 1977. pseudoetevatus BTI 4 - Lexostomoides/Nuttalides;

BTI 5 - Uvigerina spp. BTI - Eponides elevatus. O 10S

3. Turonian to Maastrichtian (zonation based on Gofas, 1985) PHASE-V : ACCELERATED PLATE SEPARATION AND FURTHER SEA -LEVEL RISE.

A) C. litterarius B) M. obtusus

Planktonic Zone CS 9-Rugoglobigerina; CS 6/8 - Contusotruncana Biostratigraphy: Explanation PHASE-VI : DROP IN RATE OF PLATE SEPARATION, FALL IN SEA-LEVEL. C

I

Cabinda Palynomorphs: Zonation by Chevron fornicata; T

PHASE-VII : SUBSTANTIAL FALL IN SEA-LEVEL, NON DEPOSITION ON THE MARGIN. 5 - Oligocene - Miocene _Pliocene Lobito

Congo Palynomorphs: Zonation by Drapeau, 1984. CS 5 - Dicarinela carinata; CS 4 - Praeglobotruncana inornata; WESTWARD TILT AND STRONG UPLIFT. N

Planktonics (zonation based on Meijer, 1972) A Kwanza Basin CS 3 - Archaeoglobigerina; CS 2 - Whiteinella spp. PHASE-VIII : RISE FOLLOWED BY FALL IN SEA-LEVEL LEAD TO TRANSGRESSION TSI - Globigerina ampliapertura; TS 2 - Globigerina L Lucira angulisuturalis; TS 3 - Globigerinoides primordius; AND REGRESSION. SECOND TIME, WESTWARD TILT AND MARGIN UPLIFT. T Ostracods: 1. Cypridea spp. 2. Hourcquia africana Benthonics: BCS 8/9 - Orthokarstenia clavata; TS 4 - Globigerinita; TS 5 - Globigerinatella insueta; 3. Cypridea aff. salvadorensis, 4. Petrobrasia tenuistriatra TS 6 - Globorotalia fohsi s.l.; TS 7 - Globorotalia siakensis; A For elaboration of tectonic phase, Refer Namibe 15S 5. Cypridea spp. 6. Candona cf. gregaria, 7. Reconcavona ? polita, BCS 6/7 - Orthokarstenia dentata/Gabonita elongata; TS 8 - Globorotalia menardii; TS 9 - Globorotalia acostaensis; TS 10 - Globorotalia margaritae. “Avaliação de Formações de Angola”, NAMIBE 8. Paracypridea brasiliersis SCHLUMBERGER, 1991 BASIN BCS 4/5 - Stensioeina spp; Calcareous nannoplankton: similar to Congo Benthonics (zonation based on Gofas, 1985) BTS 1 - Uvigerina alazanesis; BCS 2/3 - Gabonita obesa/Dorothia oxycona Namibia 0 Palynomorphs: Zonation by A Doerenkamp. BTS 2/3 - Gavelinella stenzelli/Uvegerina mantaensis; 100 1000km 1. Gnetaceapollenites 2. Cicatricosisporites diversus BTS 4 - Gavelinella beninensis; BTS 5/6 - Eponides eshira/ 3. Monosulcites, 4. Araucariacites, 5. Classopolis classoides, /Bolivina interjuncta; 6. Dicheiropolis etruscus, 7. Clavatipollenites hughuesii, BTS 6/7 - Marginulina costata; 8. Concavissimisporites cf. variverrucatus BTS 10 - Rectuvigerina siphogenerinoides. Autor: 11/00 DEX Computer Drafted: DEX GAD - DRAFTING INTERPRETATION DEPT.

REFERENCES: BASIN 1. Chronostratigraphic scale is from “Chronoly of Flutuating Sea Levels Since The Triassic” U. Bilal, Hardenbol and Peter R. Vail, 1987, Science. 2. Lithostratigraphic Columns - Stratigraphic Commission For Angola Sedimentary Basins, 1985. STRATIGRAPHY 3. Biostratigraphy: Mario G.P. Brandao, Laboratorio de Exploracao e Producao (Sonangol).

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