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Research about Mississippi Sound

Source-linked reports with geographic coverage including Mississippi Sound.

3 recordsLinked to original sources
USGS2025

Shallow geologic framework of the Mississippi Sound and the potential for sediment resources

The Mississippi Sound, an estuarine environment located between the mainland and barrier islands bordering the northern Gulf of America (formerly the Gulf of Mexico), serves as a vital ecosystem for the States of Mississippi and Alabama. Spanning approximately 100 kilometers from east to west and covering 1,400 square kilometers, the sound is home to marine industry and ports, and its shallow and brackish waters sustain a diverse array of marine life. Barrier islands along the southern edge of the sound separate the microtidal estuary from the Gulf of America. This protection from gulf wave action mediates current flow within the sound, resulting in predominantly fine-grained sediment deposition along the seafloor. This study, conducted by the U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers, provides insight on fluvial and tidal processes spanning the past 5,000 years. The report synthesizes existing research to provide a comprehensive overview of the sound geology, from Pleistocene origins to present-day morphology, and utilizes high-resolution single channel seismic profiles and sediment data to identify and map sedimentary deposits and morphologic features at and below the seafloor. Despite its ecological significance, the Mississippi Sound faces environmental challenges, including water-quality issues, habitat degradation, storm-induced erosion, and the ongoing threats of sea-level rise and environmental changes. This study uses the present-day understanding of the sound's geology to inform coastal management decisions, hazard assessment, and potential mineral resources.

Louisiana, Mississippi↗
USGS2012

Mississippi Sound

The Mississippi Sound is the primary body of water off the Mississippi Coast, extending from Lake Borgne, La. in the west to Mobile Bay, Ala. in the east and bordered by the barrier islands--Cat, Ship, Horn, Petit Bois, and Dauphin Islands--of Gulf Islands National Seashore to the south (Figure 1). It encompasses an estuary 293 km 2 (113 mi 2 ) large with a watershed of 259 km 2 (100 mi 2 ) and 44 km 2 (17 mi 2 ) of tidal marsh (Klein and others, b., 1998). It is approximately 129 km (80 mi) long, 3 m (10 ft) deep, and varies in width from 7.2 to 22.5 km (4.5 to 14 mi) (Klein and others, a., 1998). Average tidal range is 0.6 m (1.96 ft), with local water depth and surface level fluctuations largely affected by wind (Klein and others, b., 1998). The climate is semitropical/subtropical with south-southeast winds at approximately 10.4 kph (6.5 mph). Major rivers draining into Mississippi Sound, including the Pearl, Pascagoula, and Alabama Rivers, tend to carry high sediment loads (Klein and others, b., 1998). Inland fresh water drainage from these and other smaller rivers, as well as St. Louis and Biloxi Bays, create an estuarine environment in the Sound. Variable salinity levels can affect the productivity and survival of organisms living in the Sound, as well as economic and recreational activities. Predominate vegetation includes Juncus roemerianus (black needlerush) and Spartina alterniflora (smooth cordgrass). Shrimp, crab, oysters, and multiple species of finfish can be found in the waters of the Mississippi Sound.

Mississippi↗