A Relationship between Wave-Induced Cliff Erosion and Erosive Force of Waves

Sunamura, Tsuguo

doi:10.1086/628340

“…Coupled with sufficiently high water levels, storm generated waves have been considered a principal cause of recession along shorelines (Jibson and Odum 1994, Dewberry and Davis 1994, Davidson-Arnott and Pollard 1980, Sunamura 1976, Sunamura 1977. Unlike lake level, which plays only a passive role in coastal erosion or "sets the stage" for erosion to occur, wind generated waves on the Great Lakes are capable of eroding till bluffs both directly and indirectly (Kamphuis 1987, Carter 1976.…”

Section: Beach and Nearshore Processesmentioning

confidence: 99%

Factors Controlling Rates of Bluff Recession at Two Sites on Lake Michigan

Brown

¹

,

Mickelson

²

,

Edil

³

2005

Journal of Great Lakes Research

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“…Given the mode of platform development at Kaikoura detailed above, then the five models presented in Chapter Three Layzell1980, 1981;Trenhaile 1983a;and Sunamura 1977and Sunamura , 1978band Sunamura , 1992) cannot be applied to shore platforms at Kaikoura. This is because the underlying assumption that wave erosion causes platform development has been shown not to apply at Kaikoura.…”

Section: Models Of Platform Developmentmentioning

confidence: 99%

“…Thirdly, Sunamura (1977) proposed that the rate of cliff retreat was proportional to the erosive force of waves and could be empirically described by: This was designed on the premise that waves cause erosion of the platform.…”

Section: 7mentioning

confidence: 99%

“…The difficulty with this approach is that it does not explain what happens when resistance is over come. From physical modelling and field investigations, models have been developed to predict the elevation, width and gradient of shore platforms (Sunamura 1978b(Sunamura , 1990(Sunamura , 1991(Sunamura , 1992, and the relationship between wave force and cliff retreat (Sunamura 1977).…”

mentioning

confidence: 99%

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Development of shore platforms on Kaikoura Peninsula, South Island, New Zealand

Stephenson

¹

,

Kirk

²

2000

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Shore platforms on the Kaikoura Peninsula have been examined to determine the roles of marine and subaerial weathering processes in platform evolution. Erosion was measured to assess rates of development and processes of erosion. Lowering rates on platforms are presented from two years of monitoring using a traversing micro-erosion meter. Cliff retreats were calculated using aerial photographic interpretation. Marine processes were investigated by using deep water wave data, by measuring waves on shore platforms and by analysing measured tidal data. Weathering processes were investigated using tidal data, climate data, the Schmidt Hammer test, and a laboratory experiment on wetting and drying.Lowering rates over two years ranged from 0.07 to 19.80mm, and annual rates ranged from 0.154 to 9.194mm/yr. Rates of erosion varied with lithology and the type of platform.Erosion on Type A mudstone platforms was 1.98mm/yr; on Type B mudstone platforms erosion was 0.733mm/yr; and on limestone platforms it was 0.88mm/yr. The grand mean lowering rate for all shore platforms was 1. 13mm/yr . These rates fall in the middle of the range of published rates from previous studies at Kaikoura and at locations around the world. For the fITst time, erosion data from a traversing micro-erosion meter were presented as volumes of material eroded.The total volume of rock eroded from study sites having, each with an area of 45.4cm 2 , ranged from 1.20 to 92.50cm 3 • A significant finding was that rock surfaces swell up as indicated by a rise in surface level rather than lowering from erosion. The maximum measured swelling was 8.90mm. At some measurement sites as much as 90 per cent of measurements showed swelling over a period of 98 days. Values for erosion and swelling were higher during summer months.Both erosion and swelling were shown to be statistically related to season, suggesting that weathering is the group of processes causing both erosion and swelling. Summer provides better conditions for wetting and drying, which is thought to be the most important weathering process on shore platforms. Horizontal retreat rates were calculated over 52 years for cliffs, beaches and lagoon deposits backing shore platforms at Kaikoura, these ranged from 0.05 to 0.91mJyr.Investigation of marine processes showed that the deep water wave environment off the Kaikoura Peninsula is very energetic, but the amount of wave energy delivered to platforms is very low. A comparison of deep water wave energy flux with wave energy flux at the landward cliff of platforms, showed that there was a reduction by as much as five orders of magnitude. An analysis of the role of breaking waves revealed that these were ineffective as an erosional agent ii because the depth of water offshore causes breaking well before waves arrive on platform surfaces. Shear stresses and dynamic forces under waves were calculated from waves measured on shore platforms. TIus showed that these forces never exceeded the compressive strength the platform rocks at Kaikoura. It was co...

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“…Rather, direct field evidence oflow tide cliff recession is required. Sunamura (1977) investigated the relationship between cliff erosion and the erosive force of waves. He proposed that cliff erosion was controlled by the relationship between the erosive force of waves and the resisting force of rock, but the obvious difficulty of quantification of these variables was noted.…”

mentioning

confidence: 99%

Development of shore platforms on Kaikoura Peninsula, South Island, New Zealand

Stephenson

¹

,

Kirk

²

2000

View full text Add to dashboard Cite

Shore platforms on the Kaikoura Peninsula have been examined to determine the roles of marine and subaerial weathering processes in platform evolution. Erosion was measured to assess rates of development and processes of erosion. Lowering rates on platforms are presented from two years of monitoring using a traversing micro-erosion meter. Cliff retreats were calculated using aerial photographic interpretation. Marine processes were investigated by using deep water wave data, by measuring waves on shore platforms and by analysing measured tidal data. Weathering processes were investigated using tidal data, climate data, the Schmidt Hammer test, and a laboratory experiment on wetting and drying.Lowering rates over two years ranged from 0.07 to 19.80mm, and annual rates ranged from 0.154 to 9.194mm/yr. Rates of erosion varied with lithology and the type of platform.Erosion on Type A mudstone platforms was 1.98mm/yr; on Type B mudstone platforms erosion was 0.733mm/yr; and on limestone platforms it was 0.88mm/yr. The grand mean lowering rate for all shore platforms was 1. 13mm/yr . These rates fall in the middle of the range of published rates from previous studies at Kaikoura and at locations around the world. For the fITst time, erosion data from a traversing micro-erosion meter were presented as volumes of material eroded.The total volume of rock eroded from study sites having, each with an area of 45.4cm 2 , ranged from 1.20 to 92.50cm 3 • A significant finding was that rock surfaces swell up as indicated by a rise in surface level rather than lowering from erosion. The maximum measured swelling was 8.90mm. At some measurement sites as much as 90 per cent of measurements showed swelling over a period of 98 days. Values for erosion and swelling were higher during summer months.Both erosion and swelling were shown to be statistically related to season, suggesting that weathering is the group of processes causing both erosion and swelling. Summer provides better conditions for wetting and drying, which is thought to be the most important weathering process on shore platforms. Horizontal retreat rates were calculated over 52 years for cliffs, beaches and lagoon deposits backing shore platforms at Kaikoura, these ranged from 0.05 to 0.91mJyr.Investigation of marine processes showed that the deep water wave environment off the Kaikoura Peninsula is very energetic, but the amount of wave energy delivered to platforms is very low. A comparison of deep water wave energy flux with wave energy flux at the landward cliff of platforms, showed that there was a reduction by as much as five orders of magnitude. An analysis of the role of breaking waves revealed that these were ineffective as an erosional agent ii because the depth of water offshore causes breaking well before waves arrive on platform surfaces. Shear stresses and dynamic forces under waves were calculated from waves measured on shore platforms. TIus showed that these forces never exceeded the compressive strength the platform rocks at Kaikoura. It was co...

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A Relationship between Wave-Induced Cliff Erosion and Erosive Force of Waves

Cited by 104 publications

References 4 publications

Factors Controlling Rates of Bluff Recession at Two Sites on Lake Michigan

Factors Controlling Rates of Bluff Recession at Two Sites on Lake Michigan

Development of shore platforms on Kaikoura Peninsula, South Island, New Zealand

Development of shore platforms on Kaikoura Peninsula, South Island, New Zealand

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