Search USGSSearch

Geology topics

M.A. Kulp

Publications and source records attributed to M.A. Kulp.

2 recordsLinked to original sources

Archive of Sediment Data Collected around the Chandeleur Islands and Breton Island in 2007 and 1987 (Vibracore Surveys: 07SCC04, 07SCC05, and 87039)

In 2006 and 2007, the U.S. Geological Survey (USGS) and collaborators at the University of New Orleans (UNO) collected high-resolution seismic profiles and subsurface cores around the Chandeleur and Breton Islands, Louisiana (Study Area Map). To ground-truth the acoustic seismic surveys conducted in 2006, 124 vibracores were acquired during the 07SCC04 and 07SCC05 cruises in 2007. These cores were collected within the back-barrier, nearshore, and offshore environments. The surveys were conducted as part of a post-hurricane assessment and sediment resource inventory for the Barrier Island Coastal Monitoring (BICM) project. Vibracores were collected offshore using the USGS R/V G.K. Gilbert, while the terrestrial, back-barrier, and nearshore vibracores were collected from the UNO R/V Greenhead. This report serves as an archive of sediment data from two concurrent vibracore surveys (cruises 07SCC04 and 07SCC05) from around the Breton and Chandeleur Islands in 2007 and also documents sediment data from vibracores collected offshore of the Chandeleur Islands in 1987 (cruise 87039). The 1987 vibracores were collected through the collaborated efforts of the USGS, Louisiana Geological Survey (LGS), and Alpine Ocean Seismic. Each vibracore can be identified by cruise and core number.

Data Series

Delta lobe degradation and hurricane impacts governing large-scale coastal behavior, South-central Louisiana, USA

A large deficit in the coastal sediment budget, high rates of relative sea-level rise (???0.9 cm/year), and storm-induced current and wave erosion are forcing barrier shoreface retreat along the periphery of the Mississippi River delta plain. Additionally, conversion of interior wetlands to open water has increased the bay tidal prism, resulting in degradation of barrier islands due to inlet widening, formation of new inlets, and sediment sequestration at ebb-tidal deltas. Single-beam bathymetric surveys along a 165-km stretch of south-central Louisiana barrier coast, from Raccoon Point in Terrebonne Parish to Sandy Point in Plaquemines Parish, were conducted in 2006. These data, combined with historical bathymetry from three time periods (dating to the 1880s), provide a series of digital elevation models that were used to calculate sediment volumetric changes and determine long-term erosional-depositional trends. Dominant patterns during the 125-year period include (1) erosion of ???1.6????????10 9 m 3 from the shoreface, forcing up to 3 km of shoreface retreat, (2) sediment deposition in coastal bights and at ebb-tidal deltas, and (3) a combined increase in tidal inlet cross-sectional area from ???41,400 m 2 to ???139,500 m 2 . Bathymetric and shoreline change datasets separated by shorter time periods (sub-annual) demonstrate that these long-term trends are driven by processes associated with major hurricane impacts, and that rates of shoreface erosion are an order of magnitude greater during active hurricane seasons compared to long-term trends. ?? 2009 Springer-Verlag.

Geo-Marine Letters