Skip to main content

Clinoform progradation by turbidity currents: Modeling and experiments

Publication ,  Journal Article
Gerber, TP; Pratson, LF; Wolinsky, MA; Steel, R; Mohr, J; Swenson, JB; Paola, C
Published in: Journal of Sedimentary Research
January 1, 2008

Clinoform morphologies and growth patterns are typically viewed as the product of a particular mode of sediment transport, but process-specific models for their generation from turbidity currents are few, despite observations of turbidity currents on modern clinoforms and turbidites in ancient clinoform deposits. We present a simple morphodynamic model, supported by laboratory experiments, which shows how net-depositional turbidity currents can build sedimentary clinoforms. Most conceptual models for clinoform evolution assume that under constant (sea level, sediment supply) forcing progradation occurs via continuous basinward migration of a depocenter localized near the clinoform rollover. Abrupt basinward shifts in depocenter location are therefore an indication of allogenic variability in forcing. In contrast, our results document a unique style of progradation driven by autogenic cycles of slope steepening, sediment bypass, and depositional backstepping on the foreset slope. In experiments designed to investigate this slope-flow feedback, deposition from a continuous turbidity current transporting fine sand and silt repeatedly steepened a clinoform foreset to a graded slope which bypassed sediment to the slope base, depositing a sediment lobe. Continued deposition then caused the lobe to backstep up the slope, building a lower-slope foreset and eventually reinitiating the cycle. Our model shows how this cyclic depositional pattern arises from a morphodynamic feedback between the foreset gradient and the rate of sediment resuspension by the overriding turbidity current. Using our model to scale experimental results to the field, we predict gradual foreset steepening in prograding turbidity-current- dominated clinoform strata, with slope grading and cyclic deposition favored where these clinoforms build over steep basin slopes under conditions of high sediment supply and/or lateral confinement. We demonstrate how our results can add new insight to process-based interpretation of clinoform strata by application to a modern and an ancient field example. Copyright © 2008, SEPM (Society for Sedimentary Geology).

Duke Scholars

Altmetric Attention Stats
Dimensions Citation Stats

Published In

Journal of Sedimentary Research

DOI

ISSN

1527-1404

Publication Date

January 1, 2008

Volume

78

Issue

3-4

Start / End Page

220 / 238

Related Subject Headings

  • Geology
  • 3705 Geology
  • 0403 Geology
 

Citation

APA
Chicago
ICMJE
MLA
NLM
Gerber, T. P., Pratson, L. F., Wolinsky, M. A., Steel, R., Mohr, J., Swenson, J. B., & Paola, C. (2008). Clinoform progradation by turbidity currents: Modeling and experiments. Journal of Sedimentary Research, 78(3–4), 220–238. https://doi.org/10.2110/jsr.2008.023
Gerber, T. P., L. F. Pratson, M. A. Wolinsky, R. Steel, J. Mohr, J. B. Swenson, and C. Paola. “Clinoform progradation by turbidity currents: Modeling and experiments.” Journal of Sedimentary Research 78, no. 3–4 (January 1, 2008): 220–38. https://doi.org/10.2110/jsr.2008.023.
Gerber TP, Pratson LF, Wolinsky MA, Steel R, Mohr J, Swenson JB, et al. Clinoform progradation by turbidity currents: Modeling and experiments. Journal of Sedimentary Research. 2008 Jan 1;78(3–4):220–38.
Gerber, T. P., et al. “Clinoform progradation by turbidity currents: Modeling and experiments.” Journal of Sedimentary Research, vol. 78, no. 3–4, Jan. 2008, pp. 220–38. Scopus, doi:10.2110/jsr.2008.023.
Gerber TP, Pratson LF, Wolinsky MA, Steel R, Mohr J, Swenson JB, Paola C. Clinoform progradation by turbidity currents: Modeling and experiments. Journal of Sedimentary Research. 2008 Jan 1;78(3–4):220–238.

Published In

Journal of Sedimentary Research

DOI

ISSN

1527-1404

Publication Date

January 1, 2008

Volume

78

Issue

3-4

Start / End Page

220 / 238

Related Subject Headings

  • Geology
  • 3705 Geology
  • 0403 Geology