Encyclopedia of Coastal Science

2019 Edition
| Editors: Charles W. Finkl, Christopher Makowski

Boulder Beaches

  • John McKennaEmail author
Reference work entry
DOI: https://doi.org/10.1007/978-3-319-93806-6_56

Strictly speaking a boulder beach is one where the mean clast size meets the formal definition of “boulder” in the terms of the Wentworth grade scale, that is with a mean particle dia-meter of >256 mm (−8 phi) (Wentworth 1922). However, the term is also sometimes used in a general sense to describe beaches where the sediment is a mixture of boulders and large cobbles.

Boulder beaches are found in high wave-energy environments where clasts of these large dimensions are released directly by erosion of bedrock, or where material is delivered to the shore zone by slope movements such as rockfall. In both cases sediment size is a function of joint spacing. Preformed boulders may also be supplied by erosion of Quaternary deposits such as glacial till, and by infrequent high-magnitude river floods.

While a considerable body of literature exists on gravel beaches, (usually concerned with pebbles and small cobbles), beaches of large cobbles and boulders have been neglected. This is partly...

This is a preview of subscription content, log in to check access.

Bibliography

  1. Bartrum JA (1947) The rate of rounding of beach boulders. J Geol 55:514–515CrossRefGoogle Scholar
  2. Bishop P, Hughes M (1989) Imbricate and fitted fabrics in coastal boulder deposits on the Australian east coast. Geology 17:544–547CrossRefGoogle Scholar
  3. Bluck BJ (1967) Sedimentation of beach gravels, examples from South Wales. J Sediment Petrol 37(1):128–156Google Scholar
  4. Bluck BJ (1969) Particle rounding in beach gravels. Geol Mag 106(1):1–14CrossRefGoogle Scholar
  5. Hills ES (1970) Fitting, fretting and imprisoned boulders. Nature 226:345–347CrossRefGoogle Scholar
  6. Matthews ER (1983) Measurements of beach pebble attrition in Palliser Bay, southern North Island, New Zealand. Sedimentology 30(6):787–799CrossRefGoogle Scholar
  7. Oak HL (1984) The boulder beach: a fundamentally distinct sedimentary assemblage. Ann Assoc Am Geogr 74(1):71–82CrossRefGoogle Scholar
  8. Shelley D (1968) Fitting boulders: the result of an important shore process. Nature 220:1020–1021CrossRefGoogle Scholar
  9. Shepard FP (1973) Submarine geology. Harper and Row, New YorkGoogle Scholar
  10. Wentworth CK (1922) A scale of grade and class terms for clastic sediments. J Geol 30:377–392CrossRefGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Coastal Studies Research Group, School of Environmental StudiesUniversity of UlsterColeraineUK