Geologic Evolution of Atlantic Continental Rises

ISBN-13: 9781468465020 / Angielski / Miękka / 2013 / 378 str.

C. W. Poag; P. C. Graciansky

Opis

Continental rises comprise approximately 10% of sedimentary processes by which modern and sub- the earth's surface and contain 20% of its total sedi- modern submarine fans and related features are ment volume ( 100 million cubic kilometers). How- constructed. To provide a broader perspective of conti- ever, their great depth (2,000-6,000 m) below the sea nental-rise evolution, we have organized this volume surface and distance from shore-based population cen- into four parts: ters, have kept them relatively insulated from man's geological explorations. During the last 10-15 years, 1. Part I addresses prerift and synrift tectonic and however, driven by an ever-increasing thirst for knowl- depositional aspects that account for the location, edge of our planet's nature and origin, by a rising geometry, and thickness of subsequent continental imperative to find new reserves of fossil fuels, and by a rises. demand to find safe haven for hazardous wastes, ma- 2. Part II embraces early postrift aspects, such as rine scientists have intensified their surveys of this vast subsurface structure, stratigraphy, and accumula- province. tion rates; relationships to continental slope and Voluminous geological and geophysical data from shelf deposition and to continental source terrains; multichannel and single-channel seismic-reflection and the relative effects of local and global reg- profiles, high-resolution seafloor images (SEABEAM, ulating agents, such as tectonism, eustacy, and pa- Sea MARC, GLORIA), and various gravity, piston, leoclimate. This accounts for most of the 187 and rotary cores (Deep Sea Drilling Project, Ocean million-year evolution of Atlantic continental rises.

Spis treści

Part I: Prerift and synrift evolution: Galicia continential margin: Constraints on formation of non-volcanic passive margins; Southwest Africa plate margin: Thermal history and geodynamical implications; Part II: Early postrift evolution: Antarctic continental margin: Geologic image of the Bransfield Trough, an incipient oceanic basin; Southwestern Africa continental rise: Structural and sedimentary evolution; Angola basin: Geohistory and construction of the continental rise; U.S. Middle Atlantic continental rise: Provenance, dispersal, and deposition of Jurassic to Quaternary sediments; Norweigan Continental margin: Structural and stratigraphical styles; Part III: Late postrift evolution: Southern Brazil basin: Sedimentary processses and features and implications for continental rise evolution; Southeastern New England continental rise: origin and history of slide complexes; Western Nova Scotia continental rise: Relative importance of mass wasting and deep boundary-current activity; Guinea and Ivory Coast-Ghana transform margins: Combined effects of synrift structure and postrift bottom currents on evolution and morphology; Northwest African continental rise: Effects of near-bottom processes inferred from high-resolution seismic data; Saharan continental rise: Facies distribution and sediment slides; Part IV: Synthesis; Index.