D. R. Seely, 1979. "The Evolution of Structural Highs Bordering Major Forearc Basins", Geological and Geophysical Investigations of Continental Margins, Joel S. Watkins, Lucien Montadert, Patricia Wood Dickerson
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The evolution of structural highs bordering the seaward edges of major modern forearc basins is controlled by their location at inception and two primary processes-seaward accretion, and landward understuffing. Many highs probably initiate as crustal ruptures. Seaward accretion broadens the highs. Landward understuffing elevates the highs and tends to move them in a landward direction by tilting or by failure of their inner edges by compressional folding and faulting. Forearc basins behind the highs grow seaward if accretion is accompanied by submarine elevation of progressively younger accreted section added to the structural highs. Forearc basins become narrower, however, when the highs bordering their outer edges tilt landward or fail under compression in the absence of such contemporaneous accretionary growth. Accretionary broadening has previously been discussed and is exemplified by the postulated late Mesozoic history of the northern California forearc. Landward tilting, or compressional failure, is exemplified by the Cenozoic history of the northern California forearc and is suggested by a cross-section across the Guatemalan forearc, where small landward migration similar to that of highs bordering smaller Aleutian and Chilean forearc basins is recorded.
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Geological and Geophysical Investigations of Continental Margins
Knowledge of continental margins advanced rapidly during the 1970s. Multichannel seismic reflection whose cost formerly restricted its use largely to the immediate vicinity of shallow-water prospects has become more common in deeper waters. The use of the technique by government and academic groups helped solve basc structural and evolutionary problems of rocks of the deeper offshrore. Better sources and more sophisticated processing yielded better and deeper resolution of the data. To better disseminate new knowledge of continental margins, AAPG held three meetings in 1977 to review the current status of knowledge. The papers presented at those meetings are contained in this volume. There are 32 chapters divided into the following sections: Rifted Margins; Convergent Margins; Small Basin Margins; and Resources, Comparative Structure, and Eustatic Changes in Sea Level.