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C. Dreher

Publications and source records attributed to C. Dreher.

2 recordsLinked to original sources

High-resolution stratigraphy of a Mississippi subdelta-lobe progradation in the Barataria Bight, north-central Gulf of Mexico

The coastal zone of southeastern Louisiana is the product of numerous cycles of progradation, abandonment, and marine transgression of the Mississippi River delta. Currently, the shoreline in the Barataria Bight is undergoing significant erosion and retreat, and understanding its evolution is crucial in stabilization efforts. This study uses an extensive collection of geophysical and sediment core data from Barataria Bay and offshore to develop a geologic model of the shallow (< 10 m) subsurface. The purpose of the model is twofold: (1) establish the stratigraphic architecture of a subdelta lobe of the Bayou des Families delta, deposited by the Mississippi River approximately 4000 years before present; and (2) provide a high-resolution description of the geologic framework in a context that can be applied to coastal management issues in similar fluvially dominated coastal environments worldwide. The results of the study demonstrate how high-quality geologic data from the coastal environment can be used not only to further our understanding of shoreline evolution but also to provide pertinent information for coastal management needs.

Louisiana↗

Sand resources, regional geology, and coastal processes for the restoration of the Barataria Barrier shoreline

Louisiana's barrier shorelines are rapidly eroding due to high rates of relative subsidence combined with sea-level rise, repeated storm impacts, and a diminishing sand supply. Due to these factors Louisiana's barrier shorelines are the fastest eroding shorelines in the Nation. In places, the erosion of barrier islands exceeds 65 ft/yr (20 m/yr). One of the best methods for protecting Louisiana’s coastal resources from encroachment from the sea is shoreline restoration using coastal and nearshore sediment sources. The key to restoring barrier shorelines is to find large volumes of high-quality sand and developing cost-effective shallow delivery systems to move these materials. The first major barrier shoreline restoration project proposed by Coast 2050 planners is for the Barataria Basin barrier shoreline that stretches 50 mi (80.5 km) from Belle Pass east to Sandy Point. Many of the barrier shoreline areas in Barataria Basin have become fragmented, low mounds of sand, that are easily washed over by minor storm events, that provide less available habitat than fully developed barrier islands. The objective of this study is to provide information about sand resources, coastal processes, and regional geology which can be collectively used to restore the Barataria Basin barrier shoreline. The focus of this study is the identification of sand resources for the restoration of beaches and creation of backbarrier marshes along this portion of the coast.

Open-File Report↗