Depositional styles and adjustment of channel cross sections in a seasonal deltaic system: a large scale physical experiment

• Autorzy: Luo You , Zhang Hongbin , Zhu Senlin

Identyfikatory

DOI

10.1007/s11600-021-00690-7

• Języki publikacji: EN

Abstrakty

EN

Small scale experiments provide limited mechanistic insight on the evolution of the cross-sections of the channel in a deltaic system. Here, we report the results of a large-scale tank experiment on the deltaic processes in a new river course into the Qinglan Lake. The depositional body occurred from upstream to downstream in the new river course in the depositional processes. Three depositional styles have been observed in the delta building: levee, stable-bar, and wandering-bar. Single thread and braided channels have been formed with deposits of levee style and stable-bar style. Wandering-bar style, which is an autogenic process, refers to the switching in the location of the main silting zones at different spatial–temporal scales and is frequently accompanied by avulsion, river braiding, and mainstream migration. The elevation of levees and bars increased to the bankfull elevation in the blocked river reach in the first 30~40 years and impacted the main channel flow. Comparing to the blocked river reach, the evolution of the bankfull elevation and geomorphic coefficient B0.5/H (B is width, H is water depth) of the cross-sections in the new reach indicates that the evolution pathways of the cross-sections could be divided into two stages: convergent stage and autogenic feedback stage. The convergent stage refers to a positive feedback loop, while the autogenic feedback stage is dominated by autogenic process. The present study shows the diversity of landforms, complex feedbacks and internal thresholds of a seasonal deltaic system, and the results provide another view on hydraulic geometry.

Słowa kluczowe

EN

Delta; physical model; self-adjustment; hydraulic geometry; complex feedbacks; internal threshold

PL

Delta; model fizyczny; samoregulacja; geometria hydrauliczna

• Wydawca: Instytut Geofizyki PAN ; Springer
• Czasopismo: Acta Geophysica
• Rocznik: 2021
• Tom: Vol. 69, no. 6
• Strony: 2443--2452
• Opis fizyczny: Bibliogr. 33 poz.

Twórcy

autor

Luo You

• College of Hydraulic Science and Engineering, Yangzhou University, Yangzhou, China 2 China Institute of Water Resources and Hydropower Research, Beijing, China

• https://orcid.org/0000-0002-8682-5745

autor

Zhang Hongbin

• College of Hydraulic Science and Engineering, Yangzhou University, Yangzhou, China 2 China Institute of Water Resources and Hydropower Research, Beijing, China

autor

Zhu Senlin

• College of Hydraulic Science and Engineering, Yangzhou University, Yangzhou, China 2 China Institute of Water Resources and Hydropower Research, Beijing, China

Bibliografia

• 1. Adams PN, Slingerland RL, Smith ND (2004) Variations in natural levee morphology in anastomosed channel flood plain complexes. Geomorphology 61:127–142
• 2. Chen ZC, Wang GQ, Zhan XL (1996) Experiment study of settling velocity and incipient velocity of fine plastic particles. J Hydraul Eng 2:24–28 ((in Chinese))
• 3. Clarke L (2015) Experimental alluvial fans: advances in understanding of fan dynamics and processes. Geomorphology 244:135–145
• 4. Clarke L, Quine TA, Nicholas A (2010) An experimental investigation of autogenic behaviour during alluvial fan evolution. Geomorphology 115:278–285
• 5. Clifford NJ (1996) Classics in physical geography revisited. Prog Phys Geogr 20:81–87
• 6. Davies TRH, Korup O (2007) Persistent alluvial fan head trenching resulting from large, infrequent sediment inputs. Earth Surf Proc Land 32:725–742
• 7. Dijk MV, Postma G, Kleinhans MG (2009) Autocyclic behaviour of fan deltas: an analogue experimental study. Sedimentology 56:1569–1589
• 8. Edmonds DA, Slingerl RL (2007) Mechanics of river mouth bar formation: implications for the morphodynamics of delta distributary networks. J Geophys Res Earth Surf 112:237–254
• 9. Edmonds DA, Paola C, Hoyal CJD, Sheets BA (2011) Quantitative metrics that describe river deltas and their channel networks. J Geophys Res Earth Surf 116:F4
• 10. Fagherazzi S, Edmonds DA, Nardin W, Leonardi N, Canestrelli A, Falcini F, Jerolmack DJ, Mariotti G, Rowland JC, Slingerland RL (2015) Dynamics of river mouth deposits. Rev Geophys 53(3):642–672
• 11. Fang H, He G, Liu J, Chen M (2008) 3D Numerical investigation of distorted scale in hydraulic physical model experiments. J Coastal Res 52:41–54
• 12. Ferguson RI (1986) Hydraulics and hydraulic geometry. Prog Phys Geogr 10:1–31
• 13. Gleason CJ (2015) Hydraulic geometry of natural rivers: a review and future directions. Prog Phys Geogr 39:337–360
• 14. Harman C, Stewardson M, Derose R (2008) Variability and uncertainty in reach bankfull hydraulic geometry. J Hydrol 351:13–25
• 15. Hooke RL (1967) Processes on arid-region alluvial fans. J Geol 75:438–460
• 16. Jerolmack DJ, Swenson JB (2007) Scaling relationships and evolution of distributary networks on wave influenced deltas. Geophys Res Lett 34:L23402
• 17. Kim W, Mohrig D, Twilley R, Paola C, Parker G (2009a) Is it feasible to build new land in the Mississippi river delta? EOS Trans Am Geophys Union 90:373–374
• 18. Kim W, Dai A, Muto T, Parker G (2009b) Delta progradation driven by an advancing sediment source: coupled theory and experiment describing the evolution of elongated deltas. Water Resour Res 45:495–512
• 19. Mackin JH (1948) Concept of the graded river. Geol Soc Am Bull 59:463–511
• 20. Morozova GS, Smith ND (2000) Holocene avulsion styles and sedimentation patterns of the Saskatchewan river, Cumberland Marshes, Canada. Sed Geol 130:81–105
• 21. Nicholas AP, Quine TA (2007) Modeling alluvial landform change in the absence of external environmental forcing. Geology 35:527–530
• 22. Nijhuis AG, Edmonds DA, Caldwell RL, Cederberg JA, Slingerland RL, Best JL, Parsons DR, Robinson RAJ (2015) Fluvio-deltaic avulsions during relative sea-level fall. Geology 43(8):719–722
• 23. Paola C, Twilley RR, Edmonds DA, Kim W, Mohrig D, Parker G, Viparelli E, Voller VR (2011) Natural processes in delta restoration: application to the Mississippi delta. Ann Rev Mar Sci 3:67–91
• 24. Parker G (2006) Dam removal express assessment models (DREAM). J Hydraul Res 44:291–307
• 25. Phillips JD (2014) Thresholds, mode switching, and emergent equilibrium in geomorphic systems. Earth Surf Proc Land 39:71–79
• 26. Roger LH, Dorn RI (1992) Segmentation of alluvial fans in death valley, California: new insights from surface exposure dating and laboratory modelling. Earth Surf Proc Land 17:557–574
• 27. Rowland JC, Dietrich WE, Day G, Parker G (2009a) Formation and maintenance of single-thread tie channels entering floodplain lakes: observations from three diverse river systems. J Geophys Res 114:363–374
• 28. Rowland JC, Stacey MT, Dietrich WE (2009b) Turbulent characteristics of a shallow wall-bounded plan jet: experimental implications for river mouth hydrodynamics. J Fluid Mech 627:423–449
• 29. Rowland JC, Dietrich WE, Stacey MT (2010) Morphodynamics of subaqueous levee formation: insights into river mouth morphologies arising from experiments. J Geophys Res Atmos 115:1489–1500
• 30. Schumm SA, Mosley MP, Weaver WE (1987) Experimental fluvial geomorphology. John Wiley, New York
• 31. Syvitski JPM (2008) Deltas at risk. Sustain Sci 3:23–32
• 32. Zhang RJ, Xie JH (1993) Sedimentation research in China - systematic selections. China Water and Power Press, Beijing ((in Chinese))
• 33. Zhang RJ, Xie JH, Wang MP, Huang JT (1998) River sediment dynamics, 2nd edn. China Water and Power Press, Beijing ((in Chinese))