Prolongation des zones de fractures de l'ocean atlantique dans le golfe de guinee

Introduction

“…This motion is still active today along the Romanche Fracture Zone, which offsets the Mid-Atlantic Ridge by 945 km (Fig. 1 A ;Fail et al, 1970). The area of recent investigation along this margin is the Cöte d'Ivoire-Ghana Marginal Ridge (CIGMR), which corresponds to a transition between a laterally thinned continental crust and adjacent oceanic crust (Fig.…”

“…Within the past 20 years, several marine geophysical cruises conducting gravimetry, seismic refraction, and reflection profiling, as well as deep submersible dives, have been devoted to the study of the equatorial African transform margins (Fail et al, 1970;Arens et al, 1971;Machens, 1973;Delteil et al, 1974;Emery et al, 1975;Mascle, 1976;Klingebiel, 1976;Blarez, 1986;Blarez et al, 1987;Mascle and Blarez, 1987;Mascle et al, 1989;Basile, 1990;Basile et al, 1992;Mascle et al, 1993Mascle et al, , 1994Basile et al, 1993;Mascle et al, 1995) and of their conjugate along the northern Brazilian Margin (Ponte and Asmus, 1978;Zalan et al, 1985;Costa et al, 1990). From these studies two main morpho-structural features typical of transform margins can be recognized along the Cδte d'Ivoire-Ghana Margin (Figs.…”

The Cote d'Ivoire-Ghana Transform Margin Eastern Equatorial Atlantic

“…This motion is still active today along the Romanche Fracture Zone, which offsets the Mid-Atlantic Ridge by 945 km ( Fig. la) (Fail et al, 1970). The area of particular recent investigation along this margin is the Cote d'Ivoire Marginal Ridge, which corresponds to a transition between a laterally thinned continental crust and an adjacent oceanic crust (Fig.…”

“…Margin and its conjugate, the Falkland Margin (Ewing et al, 1971;Emery et al, 1975;Scrutton, 1976Scrutton, , 1979Scrutton, , 1982Lorenzo and Mutter, 1989); b) southern Newfoundland Margin (Hayworth and Keen, 1979;Todd et al, 1988;Keen et al, 1990); c) southern margin of the Exmouth Plateau (Lorenzo et al, 1991); d) Spitzbergen Margin (Lowell, 1972;Eldholm and Talwani, 1982;Eldholm et al, 1987); and e) equatorial African transform margins (Fail et al, 1970;Arens et al, 1971;Machens, 1973;Delteil et al, 1974;Emery et al, 1975;Mascle, 1976;Klingebiel, 1976;Blarez, 1986;Blarez et al, 1987;Mascle and Blarez, 1987;Mascle et al, 1988;Mascle, Auroux, et al, 1989;Basile, 1990;Basile et al, 1992;Mascle et al, 1993;Basile et al, 1993) and their conjugate, the northern Brazilian Margin (Ponte and Asmus, 1978 ;Zalan et al, 1985 ;Costa et al, 1990). Scientific drilling was conducted adjacent to transform margins during DSDP Leg 36 (Barker, Dalziel et al, 1976) and ODP Leg 114 (Ciesielski, Kristofferson, et al, 1988) in the Falkland area and ODP Leg 122 in the Exmouth Plateau (Haq, von Rad, O'Connell, et al, 1990).…”

Pre-Cruise and Site Surveys: A Synthesis of Marine Geological and Geophysical Data on the Cote D'ivoire-Ghana Transform Margin

“…These cruises resulted in a structural reconnaissance of parts of the deep continental margin and its southern bordering ridge (Delteil et al, 1974). The structural connection between the Marginal Ridge and the fossil Romanche Fracture Zone was first pointed out by Fail et al (1970). These data were complemented by underway single-channel seismic profiles, as well as by a few dredging and coring samples collected during the African margin reconnaissance Walda cruise, also conducted on board the /.…”