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USGS · ofr70142

Morphology, sedimentation, and seismic characteristics of an arctic beach, Nome, Alaska - with economic significances

Abstract

Arctic beaches exhibit characteristics that do not occur on beaches in more temperate zones. In the summer of 1967 morphological, sedimentological, and seismic refraction studies were made on an arctic beach near Nome, Alaska, in order to better define these distinguishing characteristics. Several distinct microrelief structures are developed during ice break-up and the melting of ice and snow on the beaches including ice-pushed ridges, kaimoo ridge and deposits, sea-ice kettles, sea- ice sand and sea-ice gravel cones, micro-outwash deposits, and microdeltaic deposits. Sedimentological studies showed that sediment distribution along the beach is random with no increasing or decreasing median diameters, or sorting coefficients, or sand-gravel percentages, either along the strandline or along the beach profile. This random grain size distribution is attributed to the relatively low energy along the coast of the Seward Peninsula. Further, the beaches are insulated from the elements by ice for about 6 months out of the year and the beach sediments are disturbed annually by ice-push. Longshore drift appeared to vary from east to west during the summer of 1967 with a net transport to the east. The seismic refraction study on the Nome beach indicated that internal stratigraphy of the overburden could be interpreted and correlated with known onshore and offshore stratigraphic units. Bedrock was well defined in the seismograms and exhibited a gently undulating topography with several buried channels that may be sites of gold placer deposits.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 64.48651150004395° to 64.54332656892731° latitude; -165.5176241962923° to -165.2866473987659° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeXRIS

H. Gary Greene. 1970. Morphology, sedimentation, and seismic characteristics of an arctic beach, Nome, Alaska - with economic significances. https://doi.org/10.3133/ofr70142

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