The impact of Hurricane Diana on the north Carolina continental shelf
1987; Elsevier BV; Volume: 76; Linguagem: Inglês
10.1016/0025-3227(87)90026-0
ISSN1872-6151
AutoresNancy D Vaughan, Thomas C. Johnson, David L. Mearns, Albert C. Hine, William W. Kirby-Smith, Joseph F. Ustach, Stanley R. Riggs,
Tópico(s)Tropical and Extratropical Cyclones Research
ResumoAbstract Intense storms, including hurricanes, are believed to have an important impact upon the biota and sediment cover on the continental shelf. Hurricane Diana crossed Onslow Bay, North Carolina, during September 1984 and provided an opportunity to examine its effect on the sea floor. An area in the bay transited by the hurricane had been surveyed previously by side-scan sonar, 3.5 kHz echosounding, and underwater television. We re-surveyed the area in November 1984 with the same techniques and collected box cores for sedimentary structure analysis. The post-hurricane survey yielded no unequivocal evidence of hurricane impact on the sea floor and, surprisingly, showed an abundance of seemingly delicate benthic organisms thriving on the impacted area. Sedimentary structures in the box cores included rip-up clasts and cross-laminations that are indicative of a dynamic sedimentary environment, but they could have formed during non-hurricane storm conditions. The lack of a dramatic signature on the sea floor from Hurricane Diana is attributed to the low sediment influx and frequent occurrence of intense storms on the North Carolina shelf. These factors result in an “armored” depositional environment that shows little response to the passage of each successive storm.
Referência(s)