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Chapter 12 Basin Evolution and Sediments
RIFT BASINS, NORTH ATLANTIC
AQU, AQUIT AN BASIN
AST , ASTURIAS B.
SOCAM, SORIACAMEROS B.
a
BR.CH, BRISTOL
CHANNEL B.
WA , WESTERN
APPROACHES B.
WE , W ESSE X B.
IV'V"V'-",",,CAN, CANTABRIAN B.
GA , GALICIA BANK
b
Fig. 12.7. a Jurassie and early Cretaeeous basins on
rifted eontinental ernst of the North Atlantie oeean.
(After Hiseott et al. 1990). b United States Atlantie
eontinental rnargin between Nova Seotia and north
Florida showing loeation of late Triassie to early Jurassie rift basins (blaek) exposed on land, rift basins
below younger shelf sediments, and Mesozoie-Cenozoie basins along the shelf edge. (Modified from
(1989), Hiscott et al. (1990), Gradstein et al. (1990),
SincIair et al. (1994), and also Winterer and Hinz (1984).
I
,. OCEANi CONTINENT
BOUNDARY
Hutehinson and Klitgord 1988). c Rift basins of the
Grand Banks shelf off Newfoundland, based on seismie and gravity data. Note sub division of Grand
Banks by transfer (strike-slip) faults and ehanging
orientation of normal faults on southem Grand
Banks. (After Tankard and Welsink 1988; Welsink et
al. 1989)
General Trends
As ernstal extension in the North Atlantie progressed, the zone of aetive rifting tended to migrate
toward the axial zone of the wide rift strueture. This
oeeurred at the expense of peripheral graben and
fault systems, whieh beeame inaetive. The rifting