| Abstract: | Composition of sand grains from the beaches, reef flat, and fore reef of south Molokai, Hawaii, provides key information about the origin and transport history of sediment on the reef and adjacent beach. The most common grain types include coralline algae, coral, chemically altered carbonate, and siliciclastic grains. Minor components include calcareous algal plates (Halimeda), mollusk fragments, and foraminifera; in selected areas, these components are abundant. Similarities in composition indicate that sand grains are freely transported between the beach and the reef-flat environments, whereas the fore reef has limited exchange of sand with either the beach or the reef flat. Overall, the calcium carbonate fraction of the sand, silt, and clay increases with distance offshore from 400 to 650 m, where the percentages plateau and remain relatively stable across the fore reef. The calcium carbonate content of bottom sediment indicates that sand transport on the reef flat is generally shore parallel with little shore-normal movement. This study has implications for management of beaches and coastal resources along fringing coral reefs in that it documents the effectiveness of the wide reef flat and reef crest in blocking sand transport with the fore reef. It also indicates that sediment introduced to the inner reef flat is not quickly dispersed seaward and therefore has a relatively high residence time in that setting. |
| Genre: | Conference Paper |
| ProdID: | 70033442 |
| Citation Author: | Calhoun, R. S.; Field, M. E. |
| Citation Contributing Office: | |
| Citation Datum: | |
| Citation Day: | |
| Citation Edition: | |
| Citation Editor: | |
| Citation End Page: | 1160 |
| Citation Issue: | 5 |
| Citation Keywords: | |
| Citation Language: | English |
| Citation Larger Work Title: | Journal of Coastal Research |
| Citation LatN: | |
| Citation LatS: | |
| Citation LonE: | |
| Citation LonW: | |
| Citation Month: | |
| Citation No Pagination: | |
| Citation Number Of Pages: | 10 |
| Citation Online Only Flag: | |
| Citation Phsyical Description: | |
| Citation Projection: | |
| Citation Public Comments: | |
| Citation Publisher: | |
| Citation Series: | |
| Citation Series Code: | |
| Citation Series Number: | |
| Citation Search Results Text: | Sand composition and transport history on a fringing coral reef, Molokai, Hawaii; 2008; Conference Paper; Journal of Coastal Research; Calhoun, R. S.; Field, M. E. |
| Citation Start Page: | 1151 |
| Citation Volume: | 24 |
| Citation Year: | 2008 |
| Type: | citation/reference |
| Text: | Sand composition and transport history on a fringing coral reef, Molokai, Hawaii; 2008; Conference Paper; Journal of Coastal Research; Calhoun, R. S.; Field, M. E. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| URL (DIGITAL OBJECT IDENTIFIER): | http://dx.doi.org/10.2112/06-0699.1 |
| Date Other: | Tue, 1 Jan 2008 00:00 -0600 |
| Publisher: | |
