Figure 7. a. Cartoon section showing how passive margin sediments
(deltas, turbidites, carbonate banks) can prograde far beyond the
original position of the continental edge. 7b and 7c show a simple
method of estimating and restoring crustal extension during rifting and
passive margin formation. The cross-sectional area of the stretched
crust (hatch-pattern) must equal that of the unstretched crust after
sediment, water and mantle have been removed from the cross section.