Autogenic hiatus in fluviodeltaic successions: Geometrical modeling and physical experiments

Arti Tomer, Tetsuji Muto, Wonsuck Kim

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

Basinwide hiatal discontinuity has been generally accepted as firm evidence of a distinctive allogenic event such as tectonic movement or a complete eustatic cycle. Here we show through theoretical and experimental modeling that a largescale, hiatal discontinuous surface can be produced autogenically in fluviodeltaic successions under no changes in external dynamic forcing, i.e., constant relative sea-level rise (rate r slr) and constant sediment supply (rate q S per unit width). This "autogenic hiatus" occurs where (1) the hinterland slope is steeper than the subaqueous slope of the delta, and (2) the initial downstream length of the feeding alluvial river exceeds a critical magnitude L crt that is specified primarily by q S/r slr. In this topographic setting, the existing depositional system becomes transgressive and nondeltaic as soon as sea level starts to rise. The existing subaqueous surface is starved of sediment and progressively extends landward until alluvial length is reduced to L crt. After the retreating river has attained this critical length, the shoreline still retreats but the depositional system is restored to deltaic sedimentation. Because of this, the subaqueous surface, which was previously starved of sediment, becomes overlain by delta foreset deposits after a significant time gap. Thus a steady sea-level rise can produce all of the following: a) the strata underlying the hiatus, b) the hiatus itself, and c) the strata overlying the hiatus. Changes in r slr or q S are not required to account for the presence of a hiatus of this particular type. Numerical simulations suggest that autogenic hiatuses are likely to be produced in most natural river deltas if a sea-level rise such as occurred during latest Pleistocene to Holocene (i.e., 0.01 km/kyr for 10 kyr) is available. This further implies that autogenic hiatuses may well exist in stratigraphic records of river deltas, especially of Quaternary age. An understanding of autogenic hiatuses, when combined with the theory of shoreline autoretreat, provides an alternative view of the origin of some stratigraphic breaks.

Original languageEnglish
Pages (from-to)207-217
Number of pages11
JournalJournal of Sedimentary Research
Volume81
Issue number3
DOIs
Publication statusPublished - 2011 Mar 1

Fingerprint

hiatus
modeling
river
experiment
shoreline
deltaic sedimentation
sediment
geological record
discontinuity
Holocene
sea level
Pleistocene
tectonics
simulation
sea level rise
rate

All Science Journal Classification (ASJC) codes

  • Geology

Cite this

@article{28e2c59ef10d45a19d5fe3fa1f47d370,
title = "Autogenic hiatus in fluviodeltaic successions: Geometrical modeling and physical experiments",
abstract = "Basinwide hiatal discontinuity has been generally accepted as firm evidence of a distinctive allogenic event such as tectonic movement or a complete eustatic cycle. Here we show through theoretical and experimental modeling that a largescale, hiatal discontinuous surface can be produced autogenically in fluviodeltaic successions under no changes in external dynamic forcing, i.e., constant relative sea-level rise (rate r slr) and constant sediment supply (rate q S per unit width). This {"}autogenic hiatus{"} occurs where (1) the hinterland slope is steeper than the subaqueous slope of the delta, and (2) the initial downstream length of the feeding alluvial river exceeds a critical magnitude L crt that is specified primarily by q S/r slr. In this topographic setting, the existing depositional system becomes transgressive and nondeltaic as soon as sea level starts to rise. The existing subaqueous surface is starved of sediment and progressively extends landward until alluvial length is reduced to L crt. After the retreating river has attained this critical length, the shoreline still retreats but the depositional system is restored to deltaic sedimentation. Because of this, the subaqueous surface, which was previously starved of sediment, becomes overlain by delta foreset deposits after a significant time gap. Thus a steady sea-level rise can produce all of the following: a) the strata underlying the hiatus, b) the hiatus itself, and c) the strata overlying the hiatus. Changes in r slr or q S are not required to account for the presence of a hiatus of this particular type. Numerical simulations suggest that autogenic hiatuses are likely to be produced in most natural river deltas if a sea-level rise such as occurred during latest Pleistocene to Holocene (i.e., 0.01 km/kyr for 10 kyr) is available. This further implies that autogenic hiatuses may well exist in stratigraphic records of river deltas, especially of Quaternary age. An understanding of autogenic hiatuses, when combined with the theory of shoreline autoretreat, provides an alternative view of the origin of some stratigraphic breaks.",
author = "Arti Tomer and Tetsuji Muto and Wonsuck Kim",
year = "2011",
month = "3",
day = "1",
doi = "10.2110/jsr.2011.19",
language = "English",
volume = "81",
pages = "207--217",
journal = "Journal of Sedimentary Research",
issn = "1527-1404",
publisher = "SEPM Society for Sedimentary Geology",
number = "3",

}

Autogenic hiatus in fluviodeltaic successions : Geometrical modeling and physical experiments. / Tomer, Arti; Muto, Tetsuji; Kim, Wonsuck.

In: Journal of Sedimentary Research, Vol. 81, No. 3, 01.03.2011, p. 207-217.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Autogenic hiatus in fluviodeltaic successions

T2 - Geometrical modeling and physical experiments

AU - Tomer, Arti

AU - Muto, Tetsuji

AU - Kim, Wonsuck

PY - 2011/3/1

Y1 - 2011/3/1

N2 - Basinwide hiatal discontinuity has been generally accepted as firm evidence of a distinctive allogenic event such as tectonic movement or a complete eustatic cycle. Here we show through theoretical and experimental modeling that a largescale, hiatal discontinuous surface can be produced autogenically in fluviodeltaic successions under no changes in external dynamic forcing, i.e., constant relative sea-level rise (rate r slr) and constant sediment supply (rate q S per unit width). This "autogenic hiatus" occurs where (1) the hinterland slope is steeper than the subaqueous slope of the delta, and (2) the initial downstream length of the feeding alluvial river exceeds a critical magnitude L crt that is specified primarily by q S/r slr. In this topographic setting, the existing depositional system becomes transgressive and nondeltaic as soon as sea level starts to rise. The existing subaqueous surface is starved of sediment and progressively extends landward until alluvial length is reduced to L crt. After the retreating river has attained this critical length, the shoreline still retreats but the depositional system is restored to deltaic sedimentation. Because of this, the subaqueous surface, which was previously starved of sediment, becomes overlain by delta foreset deposits after a significant time gap. Thus a steady sea-level rise can produce all of the following: a) the strata underlying the hiatus, b) the hiatus itself, and c) the strata overlying the hiatus. Changes in r slr or q S are not required to account for the presence of a hiatus of this particular type. Numerical simulations suggest that autogenic hiatuses are likely to be produced in most natural river deltas if a sea-level rise such as occurred during latest Pleistocene to Holocene (i.e., 0.01 km/kyr for 10 kyr) is available. This further implies that autogenic hiatuses may well exist in stratigraphic records of river deltas, especially of Quaternary age. An understanding of autogenic hiatuses, when combined with the theory of shoreline autoretreat, provides an alternative view of the origin of some stratigraphic breaks.

AB - Basinwide hiatal discontinuity has been generally accepted as firm evidence of a distinctive allogenic event such as tectonic movement or a complete eustatic cycle. Here we show through theoretical and experimental modeling that a largescale, hiatal discontinuous surface can be produced autogenically in fluviodeltaic successions under no changes in external dynamic forcing, i.e., constant relative sea-level rise (rate r slr) and constant sediment supply (rate q S per unit width). This "autogenic hiatus" occurs where (1) the hinterland slope is steeper than the subaqueous slope of the delta, and (2) the initial downstream length of the feeding alluvial river exceeds a critical magnitude L crt that is specified primarily by q S/r slr. In this topographic setting, the existing depositional system becomes transgressive and nondeltaic as soon as sea level starts to rise. The existing subaqueous surface is starved of sediment and progressively extends landward until alluvial length is reduced to L crt. After the retreating river has attained this critical length, the shoreline still retreats but the depositional system is restored to deltaic sedimentation. Because of this, the subaqueous surface, which was previously starved of sediment, becomes overlain by delta foreset deposits after a significant time gap. Thus a steady sea-level rise can produce all of the following: a) the strata underlying the hiatus, b) the hiatus itself, and c) the strata overlying the hiatus. Changes in r slr or q S are not required to account for the presence of a hiatus of this particular type. Numerical simulations suggest that autogenic hiatuses are likely to be produced in most natural river deltas if a sea-level rise such as occurred during latest Pleistocene to Holocene (i.e., 0.01 km/kyr for 10 kyr) is available. This further implies that autogenic hiatuses may well exist in stratigraphic records of river deltas, especially of Quaternary age. An understanding of autogenic hiatuses, when combined with the theory of shoreline autoretreat, provides an alternative view of the origin of some stratigraphic breaks.

UR - http://www.scopus.com/inward/record.url?scp=84860321294&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84860321294&partnerID=8YFLogxK

U2 - 10.2110/jsr.2011.19

DO - 10.2110/jsr.2011.19

M3 - Article

AN - SCOPUS:84860321294

VL - 81

SP - 207

EP - 217

JO - Journal of Sedimentary Research

JF - Journal of Sedimentary Research

SN - 1527-1404

IS - 3

ER -