| Abstract: | Bed shear stress was estimated using wave and current measurements obtained with the GEOPROBE bottom-tripod system during resuspension events in Norton Sound, Alaska, and on the northern California shelf. The boundary-layer model of Grant and Madsen (1979, Journal of Geophysical Research, 84, 1797-1808) was used to compute the bed shear stress under combined wave-generated and quasi-steady currents. Resuspension events were identified by sudden, large increases in light scattering at 1.9 m above the sea floor. The shear-stress values were used to compute the Shields parameter (??). The results for Norton Sound are in excellent agreement with the Shields threshold criterion; the data for the California shelf plot somewhat above the Shields threshold curve, though generally within the scatter envelope. Although the surface sediments in each area contain substantial fine-grained fractions (mean diameters were 0.007 cm in Norton Sound and 0.002 cm on the California shelf), the results do not indicate significant cohesion, because the sediment was entrained at bed shear-stress values close to those predicted by the modified Shields curve for cohesionless fine-grained particles. We suspect that frequent wave stirring and observed plowing of the surface sediment by benthonic animals maintain a high water content and contribute to the ease with which these materials are resuspended. ?? 1986. |
| Genre: | Article |
| ProdID: | 70014551 |
| Citation Author: | Drake, D. E.; Cacchione, D. A. |
| Citation Contributing Office: | |
| Citation Datum: | |
| Citation Day: | |
| Citation Edition: | |
| Citation Editor: | |
| Citation End Page: | 429 |
| Citation Issue: | 3 |
| Citation Keywords: | |
| Citation Language: | English |
| Citation Larger Work Title: | Continental Shelf Research |
| Citation LatN: | |
| Citation LatS: | |
| Citation LonE: | |
| Citation LonW: | |
| Citation Month: | |
| Citation No Pagination: | |
| Citation Number Of Pages: | 15 |
| 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: | Field observations of bed shear stress and sediment resuspension on continental shelves, Alaska and California; 1986; Article; Journal; Continental Shelf Research; Drake, D. E.; Cacchione, D. A. |
| Citation Start Page: | 415 |
| Citation Volume: | 6 |
| Citation Year: | 1986 |
| Type: | citation/reference |
| Text: | Field observations of bed shear stress and sediment resuspension on continental shelves, Alaska and California; 1986; Article; Journal; Continental Shelf Research; Drake, D. E.; Cacchione, D. A. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| Date Other: | Wed, 1 Jan 1986 00:00 -0600 |
| Publisher: | |