AAPG Distinguished Lecture Series, 2018-19 Season

Abstract: Re-evaluating the Relationship Between Relative Sea Level and Sediment Distribution Using Numerical Stratigraphic Forward Models

Changes in relative sea level are often cited as the principal control on sediment distribution, stratal architecture, and the overall development of continental margins. Implicit to the assumptions of sequence stratigraphic models are that sediment supply is constant, the depositional system response to relative sea-level change is linear, and autogenic processes operate at relatively short spatio-temporal scales. Field studies, numerical, and physical tank experiments suggest these assumptions may not adequately characterize the behavior of sediment routing across continental margins

Changes in relative sea level are often cited as the principal control on sediment distribution, stratal architecture, and the overall development of continental margins. Implicit to the assumptions of sequence stratigraphic models are that sediment supply is constant, the depositional system response to relative sea-level change is linear, and autogenic processes operate at relatively short spatio-temporal scales. Field studies, numerical, and physical tank experiments suggest these assumptions may not adequately characterize the behavior of sediment routing across continental margins.

This presentation will review the results of recent 3D diffusion-based numerical stratigraphic forward model studies of the impact of relative sea-level on deep-water sand delivery. Model results were analyzed for the total volume of deep-water sand, and the timing, magnitude, frequency, and spatial distribution of delivery events.

Key results show that:

  1. Autogenic and allogenic processes may produce similar depositional system responses,
  2. The timing of deep-water sand delivery with respect to the relative sea-level curve may not be predicable
  3. Relative sea-level does influence the short-term character of deep-water sand delivery, but not the total volume of sand delivered
  4. Relative sea-level does not adequately capture the dimensional space in which depositional systems reside.

These results are comparable to observations in natural settings because they can account for multiple controls on sedimentation in multidimensional space. Applying a sedimentological processed-based approach to the stratigraphic record can prove critical in the exploration, assessment, and characterization of hydrocarbon reservoirs. Finally, the insights derived from well-validated numerical models can be used in continued development of sequence stratigraphic concepts.

Distinguished Lecturer

Ashley

Ashley Harris

Clastic Stratigraphic Team Lead

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Video Presentation

Contacts

Adriane Hausher Programs Coordinator
Susie Nolen Programs Team Leader +1 918 560 2634