A.D. Donovan, 2013. "Depositional Topography and Sequence Development", Shelf Margin Deltas and Linked Down Slope Petroleum Systems–Global Significance and Future Exploration Potential, Harry H. Roberts, Norman C. Rosen, Richard H. Fillon, John B. Anderson
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In siliciclastic systems, depositional sequences having distinct physiographic relief (clinoform development) can occur in epicontinental seas, across the continental shelf, along the continental margin, or even in lacustrine basins. Furthermore, this depositional topography can occur along sequence boundaries, within sequences, or downdip of the shoreline in any basin. However, not all sequences having distinct “shelf (clinoform) breaks contain basin floor lowstand fans. It appears that only those sequences with clinoform breaks beyond a critical threshold of relief and inclination contain basin floor (lowstand) fans.
Integration of published seismic, well-log, and outcrop data from wide variety of basins, suggests that three types of depositional sequences (low-, moderate-, and high-relief) should be defined. Low-relief sequences lack basin floor (lowstand) fans. They have subtle clinoforms, typically with inclinations of less than 0.5 degrees and heights less than 30 meters (100 ft), both within sequences and along sequence boundaries. Moderate-relief sequences also lack basin floor (lowstand) fans. However, they display distinct clinoforms, typically with inclinations that range from 0.5 to 2.0 degrees and heights less than 150m (500 ft), both within sequences and along sequence boundaries. High-relief sequences contain basin floor (lowstand) fans. They have well-developed clinoforms, in which inclinations and heights, respectively, are greater than 2 degrees and 180 meters (600 ft), both within sequences and along sequence boundaries. These relationships suggest that there is a stable limit to topographic development that controls clinoform stability or failure during relative sea level falls. In basins where the depositional relief is less than the stable limit to topographic development, progradation continues during relative sea-level falls. The resulting low- to moderate-relief sequences lack basin-floor (lowstand) fans. In basins where the depositional relief is greater than the stable limit to topographic development, slumping, canyon formation, fluvial capture, and sediment by-pass occur during relative sea level falls. The resulting high-relief sequences contain basin floor (lowstand) fans. In siliciclastic systems, this boundary condition appears to occur in the range of 500-600 ft (150-180m) of vertical relief.