Paleogeography and Tectono-Stratigraphy of Carboniferous-Permian and Triassic ‘Karoo-Like’ Sequences of the Congo Basin - Geology and Resource Potential of the Congo Basin - page 115

A B

Dekese

Samba

46

5

82

73A 80

45

49

27

44 71

115 2 6 73

28 25 15

29 22 39 72 81

117 70

1270

24 23A 40 36

1920

38

2000 1900

1950

37

1850

16

2000 1900

1700 1810

2330

4860 2100 1950 2090 1950

2000 1970 1950

1850

2000
2250

2100 2500

2350 2060 2050 2020 2150

2050 2400 1980 1960 1900

2860 2540

1970

2500 2260 2420 2780

2300

2710

2400

2570 2450 3000

2450 3000

2700 3000

2710

2685 2780

3700 2700

2600

2620 2580 3070

5250

4680 500

3000

4450 500 500

2720 500 2710

3000 2770 500

2830

500 2870 500

3000 500

500

500 500 500

500 500 500 500

500 500 500

500 500 500 3040 500 500 3410 3340 3200 3100

500

3600 2740 3000 500

500

5100

3150 3000

2730 3430

3180

3400 4400

3200 3650

3100

4200

4

3000

Vertical
exageration
x 25

3200

3700

3600 3600

3

3240

3600

2

1000

3600

3600

4400

1000

1000

4300 1000 3600

1000

1000 4500

1000

4200

1000 4100 4200 1000

1000 1000 1000

1000 1000 1000 1000

4300 1000 3750 5700

1000 1000 1000 1000

1000 5200

4300 1000

1000

4300

4200

3850

4450 4350

4100

4300 4200

6000

5200 5200 4300

4600

1500 4400

1500

5300

1500

1500

5300 1500 4200

1500 1500 1500

1500

5200

4200

1500

4530

5200

5200

100 km

2000

4500

2000

2000

5200

2000 2000

2000

2000

5000

5200

1

4600

5860

Seismic velocities (m/s) diagram frequency 6050

2500

12

2500 2500

10

5550

8

6

4

3000

5700

2

0

<2200 m/s 2300-3600 m/s
3600-3900 m/s

>5200 m/s

4200-4600 m/s

Dekese

Samba

Kalahari Group

Kwango Group

Aruwimi
Group

Loia and Bokungu Group

Stanleyville Group

Lukuga Group

Haute Lueki Group

KASAI
CRATON

Fig. 7.6 N-S seismic refraction profile (data are from Evrard 1960 ),
850 km long across the Samba and Dekese sections (Fig. 7.2A for
location). The upper profile shows five distinct units separated by
seismic discontinuities: (1) basement rocks ( > 5,200 m/s); (2) quartzitic
sandstones (4,200-4,600 m/s);

(3,600-3,900 m/s); (4) poorly consolidated sandstones and mudstones
(3,000 and 3,300-3,600 m/s); and (5) uppermost unconsolidated mate-
rial ( < 2,200 m/s). Lower figure is a schematic interpretation ( arrows
pointing up represent cross-cutting relationships)

(3) black shales and diamictites