Late Holocene evolution of a retrograding barrier : Hutaff Island, North Carolina

UNCW Author/Contributor (non-UNCW co-authors, if there are any, appear on document)
Benjamin Adam McGinnis (Creator)
Institution
The University of North Carolina Wilmington (UNCW )
Web Site: http://library.uncw.edu/
Advisor
William Cleary

Abstract: Hutaff Island is a 6.0-km (3.7-mile) long undeveloped barrier located in southwestern Onslow Bay, North Carolina. The barrier is bordered by New Topsail Inlet to the northeast and Rich Inlet to the southwest, and has historically been influenced by several adjacent tidal inlets with contrasting behaviors. Severe storm events have frequently impacted the barrier throughout the 1938 – 2002 study period, resulting in dramatic erosion and overtopping of the barrier. The development of major washover terraces coupled with storm-induced dune erosion has dramatically lowered the barrier’s topography. Consequently, the island is poised to migrate landward at accelerated rates during future high-energy storm events. The shoreface that fronts the barrier consists of a thin veneer of modern sand and gravelly sand. The mobile surface veneer is generally less than 1.0 m thick and overlies an easily eroded Oligocene siltstone unit that frequently crops out on the inner shoreface forming low-relief hardbottoms. Vibracore sequences recovered from the estuary contain inter-bedded clean and muddy sand units. The sand-rich intertidal and shallow subtidal sequences recovered near the barrier reflect the role of the numerous inlets that have cycled trough the area. Long-term shoreline change rates showed that Hutaff Island had experienced an average net loss of ~ 2.1 m/year (7.0 ft/year) between 1938 and 2002. A dramatic lowering of the barrier profile accompanied this landward translation. The relatively high erosion rates and increased washover susceptibility appear to be attributable to a combination of variables, including the region’s low sediment supply and the persistent presence of unstable inlets. An understanding of the processes influencing Hutaff Island’s evolution can be used as a model in formulating management decisions on nearby barriers where it is often difficult to assess the active processes and changes taking place as a result of dense coastal development and its associated anthropogenic effects.

Additional Information

Publication
Thesis
A Thesis Submitted to the University of North Carolina at Wilmington in Partial Fulfillment Of the Requirements for the Degree of Master of Science
Language: English
Date: 2009
Keywords
Barrier islands--North Carolina, Beach erosion--North Carolina--Hutaff Island, Coastal zone management--North Carolina, Erosion--North Carolina--Hutaff Island, Geology, stratigraphic--Holocene, Geology, Stratigraphic--Oligocene, Shore protection--North Carolina--Hutaff Island
Subjects
Geology, Stratigraphic -- Oligocene
Erosion -- North Carolina -- Hutaff Island
Barrier islands -- North Carolina
Geology, stratigraphic -- Holocene
Beach erosion -- North Carolina -- Hutaff Island
Shore protection -- North Carolina -- Hutaff Island
Coastal zone management -- North Carolina

Email this document to