Page 211 - Global Tectonics

60°W 30°W 0°
(a)
60°N 60°N
SW Greenland M A R
Labrador
North America
Flemish Cap
Goban Spur
45°N 45°N
Galicia Bank
Newfoundland Basin Iberia Abyssal Iberia
M A R Plain
30°N Africa 30°N
60°W 30°W 0°

(b) 0
Oceanic Exhumed mantle Continental
5 2.0 2.0 Galicia
Bank
4.0 4.0
10 6.0 7.0 6.0 7.0
Depth (km) 15 8.0 8.0
20
25
Iberia Abyssal Plain
30
280 260 240 220 200 180 160 140 120 100 80 60 40 20 0
Distance (km)

0
(c)
Water
Sediment
10
Oceanic PR Transitional S
M Continental
20 Depth (km)
Upper mantle
Ocean–continent transition zone 30
M
Iberia
40
100–150km

(d) Water Sediment 0
Oceanic
M Transitional 10
Continental
Depth (km)
20
Upper mantle
Ocean–continent transition zone M
30
Labrador
40
Figure 7.34 (a) Map of the North Atlantic showing location of selected nonvolcanic margins. MAR, Mid-Atlantic Ridge.

(b) Velocity model of the West Iberia margin and the Iberia Abyssal Plain (image provided by T. Minshull and modified
from Minshull, 2002 with permission from Royal Society of London). Data are from Dean et al. (2000). The dashed lines
−1
mark the approximate edges of the ocean–continent transition zone. Velocities in km s . (c,d) Two end-member types of
nonvolcanic margin (images provided by K. Louden and modified from Louden & Chian, 1999, with permission from the

Royal Society of London). PR, peridotite ridge; S, reflections interpreted to represent a detachment fault or shear zone;

M, Moho reflections.