Gravity anomalies at rifted continental margins and their geological significance.

The free-air gravity "edge effect" anomaly at rifted continental margins is one of the most distinctive features of the marine gravity field. The "edge effect", which comprises of a positive- negative "couple" has traditionally been interpreted as the consequence of the juxtaposition of thick continental crust against thin oceanic crust. This essay explores the role that geological processes such as rifting, flexure, sedimentation, and magmatism may contribute to the "edge effect" anomaly and investigates how it might be used, together with other geophysical data, to determine the boundary that separates continental and oceanic crust.

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