. Collected reprints / Atlantic Oceanographic and Meteorological Laboratories [and] Pacific Oceanographic Laboratories. Oceanography 312 C O N TI N K N T A I SHE! F SEDIMENTATION complex mosaic of sediment types, rather than a simple seaward-fining sheet. He suggested that these patches were deposited during Pleistocene low stands of the sea, rather than during Recent time. Emery (1952, 1968) raised this concept to the status of a new conceptual model. He classified shelf sediments on a genetic basis, as autlugenic (glauconite or phosphorite), organic (fcramini- fera, shells), re
. Collected reprints / Atlantic Oceanographic and Meteorological Laboratories [and] Pacific Oceanographic Laboratories. Oceanography 312 C O N TI N K N T A I SHE! F SEDIMENTATION complex mosaic of sediment types, rather than a simple seaward-fining sheet. He suggested that these patches were deposited during Pleistocene low stands of the sea, rather than during Recent time. Emery (1952, 1968) raised this concept to the status of a new conceptual model. He classified shelf sediments on a genetic basis, as autlugenic (glauconite or phosphorite), organic (fcramini- fera, shells), residual (weathered from underlying rock), relict (remnant from a different earlier environment such as a now submerged beach or dune), and detrual, which includes material now being supplied by rivers, coastal erosion, and eolian or glacial activity. On most shelves, a thin nearshore band of modern detrital sedi- ment' is supposed to give way seaward to a relict sand sheet veneering the shelf surface. A third, more generalized model for shelf sedimenta- tion has been primarily concerned with the resulting stratigraphy. It incorporates elements of both the Johnson and Emery models. Like the Johnson model, it views the shelf surface as a dynamic system in a state of equilibrium with a set of process variables. The rate of sea-level change, however, is one of these variables; hence the effects of post-Pleistocene sea-level rise, as noted by Shepard and Emery, may be accounted for. The model may be referred to as the transgression- regression model, since it is generally expressed in these terms, or the coastal model, since it focuses on the behavior of this dynamic zone. It was first explicitly formulated by Grabau (1913), and more recently by Curray (1964) and Swift et al. (1972). In this model, the rate of sediment input to the continental shelf S, the character of the sediment G (grain size and mineralogy), the rate of energy input E, the sense and rate of relative sea-level cha
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