Shore Processes and Shoreline Development

Johnson, Douglas W.

doi:10.1080/11035892009442361

Cited by 166 publications

(107 citation statements)

References 0 publications

Supporting

Mentioning

100

Contrasting

Unclassified

Order By: Relevance

“…Johnson (1919) proposed that width increased through time, but the rate of extension decreased over time. Edwards (1941) considered the width of a platform to be controlled by the relative difference in the rate of retreat of the low and high tide cliffs.…”

Section: Shore Platform Widthmentioning

confidence: 99%

“…No erosion will occur where Fw (z) < FR(Z). The lower part of tbe cliff does not tberefore erode (Sunamura 1992 (Davis 1896, andJohnson 1919). Bartrum (1916Bartrum ( , 1924Bartrum ( , 1926Bartrum ( , 1935 distinguished between platforms of the Old Hat type with an elevation slightly below high tide and storm wave platforms with elevations several metres above high tide.…”

Section: = Is a Reduction Coefficient Of Fwmentioning

confidence: 99%

“…Such terms include: shore platform (Dana 1849;Bartrum 1935Bartrum , 1938Jutson 1939;Wentworth 1938Wentworth , 1939Wentworth , 1940Hills 1949;Edwards 1951;Cotton 1963;Mil 1962;Bird and Dent 1966;McLean and Davidson 1968;Healy 1968a, Hills 1971Trenhaile 1971Trenhaile , 1972Trenhaile , 1974aTrenhaile , 1974bTrenhaile , 1978Trenhaile , 1980Trenhaile , 1983aTrenhaile , 1983bAbrahams and Oak 1975;Takahashi 1975Takahashi , 1977Robinson 1977aSunamura 1978aSunamura , 1983Sunamura , 1990Sunamura , 1991Sunamura , 1992Layzell1980, 1981;Hansom 1983;Trenhaile and Bryne 1986;Tsujimoto 1987;Lawrie 1993;Griggs and Trenhaile 1994), rock bench (Bell and Clarke 1909), high water rock platform and Old Hat Type platform (Bartrum 1916), abrasion platform (Johnson 1919;Cinque et al 1995), shore bench …”

Section: Thesis Aimsmentioning

confidence: 99%

“…The width of shore platforms have been considered by a number of authors (Dana 1849;Johnson 1919;Edwards 1941;Trenhaile, 1972Trenhaile, , 1978Trenhaile, , 1983Trenhaile and LayzeU 1981;Sunamura 1992). Johnson (1919) proposed that width increased through time, but the rate of extension decreased over time.…”

Section: Shore Platform Widthmentioning

confidence: 99%

See 3 more Smart Citations

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

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...

show abstract

Section: Shore Platform Widthmentioning

confidence: 99%

Section: = Is a Reduction Coefficient Of Fwmentioning

confidence: 99%

Section: Thesis Aimsmentioning

confidence: 99%

Section: Shore Platform Widthmentioning

confidence: 99%

See 2 more Smart Citations

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

2000

View full text Add to dashboard Cite

show abstract

“…Hesp, 1999Hesp, , 2006Tanner, 1995;Taylor and Stone, 1996). Some authors have suggested that beach ridges consist exclusively of wave built features (Johnson, 1919;Hesp, 1999) whereas others such as Tanner (2000) suggest that both waves and wind can be responsible. Here we refer to beach ridges sensu Hesp (1999Hesp ( , 2006 who defined beach ridges as principally or purely marine deposits of triangular to convex form located in the backshore at or above the normal spring high tide level.…”

Section: Methodsmentioning

confidence: 99%

The origin of centennial- to millennial-scale chronological gaps in storm emplaced beach ridge plains

et al. 2015

View full text Add to dashboard Cite

Beach cusp morphodynamics

Masselink

Hegge

Pattiaratchi

1997

Earth Surf. Process. Landforms

View full text Add to dashboard Cite

Detailed measurements of three-dimensional beach cusp morphology were made on a steep gradient, low energy, microtidal beach in Perth, Western Australia. During the field campaign a variety of wave conditions and tidal ranges were experienced, and these differing hydrodynamic conditions were reflected in a consistent pattern of morphological changes to the beach cusp system. A useful parameter to delineate between trends of cusp destruction and re-formation appeared to be the surf similarity parameter ξ = tan β⁄√H o ⁄L o , where H o is offshore wave height, L o is deep water wave length and tan β is beach gradient. For ξ<1·2 the beach cusps were planed off, whereas cusp morphology was enhanced when ξ>1·2.A small storm was experienced at the start of the field campaign period and resulted in considerable erosion of the beach face. The cusp morphology across the lower beachface was destroyed, but a subtle remnant of the pre-storm cusp morphology was preserved on the upper beachface. When cusps reformed after the storm, under the influence of declining wave conditions, they appeared at the same location and with the same dimensions as the pre-storm cusp morphology. Hence, it is considered that the cusp re-formation was controlled more by the antecedent morphology than the hydrodynamic conditions. This indicates that positive feedback between swash hydrodynamics and beachface morphology, necessary to form beach cusps, does not require a large variation in relief.

show abstract

Shore Processes and Shoreline Development

Cited by 166 publications

References 0 publications

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

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

The origin of centennial- to millennial-scale chronological gaps in storm emplaced beach ridge plains

Beach cusp morphodynamics

Contact Info

Product

Resources

About