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Geology topics

Kathryn E. L. Smith

Publications and source records attributed to Kathryn E. L. Smith.

9 recordsLinked to original sources

Analysis of shoreline and geomorphic change for Breton Island, Louisiana, from 1869 to 2014

Many barrier islands in the United States are eroding and losing elevation substantively because of storm surge, waves, and sea-level changes. This is particularly true for the deltaic barrier system in Louisiana. Breton Island is near the mouth of the Mississippi River at the southern end of the Chandeleur barrier island chain in southeast Louisiana. This report expands on previous geomorphic studies of Breton Island by incorporating additional historic and recent datasets. Multiple analyses focus on longand short-term shoreline change, as well as episodic events and anthropogenic modification. Analyses periods include long term (1869–2014), long-term historic (1869–1950), post-Mississippi River-Gulf Outlet (1950–2014), pre/post-Hurricane Katrina (2004–5), and recent (2005–14). In addition to shoreline change, barrier island geomorphology is evaluated using island area, elevation, and sediment volume change. In the long term (1869–2014), Breton Island was affected by landward transgression, island narrowing, and elevation loss. Major storm events exacerbated the long-term trends. In the recent period (2005–14), Breton Island eroded at a slower rate than in the long-term and gained area and total sediment volume. The recent accretion is likely because of the lack of major storms since Hurricane Katrina in 2005.

Louisiana

Wetland paleoecological study of southwest coastal Louisiana: sediment cores and diatom calibration dataset

Wetland sediment data were collected in 2009 and 2010 throughout the southwest Louisiana Chenier Plain as part of a pilot study to develop a diatom-based proxy for past wetland water chemistry and the identification of sediment deposits from tropical storms. The complete dataset includes forty-six surface sediment samples and nine sediment cores. The surface sediment samples were collected in fresh, intermediate, and brackish marsh and are located coincident with Coastwide Reference Monitoring System (CRMS) sites. The nine sediment cores were collected at the Rockefeller Wildlife Refuge (RWR) located in Grand Chenier, La.

Louisiana

Morphology, ecology and biogeography of Stauroneis pachycephala P.T. Cleve (Bacillariophyta) and its transfer to the genus Envekadea

Stauroneis pachycephala was described in 1881 from the Baakens River, Port Elizabeth, South Africa. Recently, it was found during surveys of the MacKenzie River (Victoria, Australia), the Florida Everglades (USA) and coastal marshes of Louisiana (USA). The morphology, ecology and geographic distribution of this species are described in this article. This naviculoid species is characterised by lanceolate valves with a gibbous centre, a sigmoid raphe, an axial area narrowing toward the valve ends, and capitate valve apices. The central area is a distinct stauros that is slightly widened near the valve margin. The raphe is straight and filiform, and the terminal raphe fissures are strongly deflected in opposite directions. Striae are fine and radiate in the middle of the valve, becoming parallel and eventually convergent toward the valve ends. The external surface of the valves and copulae is smooth and lacks ornamentation. We also examined the type material of S. pachycephala . Our observations show this species has morphological characteristics that fit within the genus Envekadea. Therefore, the transfer of S. pachycephala to Envekadea is proposed and a lectotype is designated.

Florida;Louisiana;Victoria

Hurricane Sandy: observations and analysis of coastal change

Hurricane Sandy, the largest Atlantic hurricane on record, made landfall on October 29, 2012, and impacted a long swath of the U.S. Atlantic coastline. The barrier islands were breached in a number of places and beach and dune erosion occurred along most of the Mid-Atlantic coast. As a part of the National Assessment of Coastal Change Hazards project, the U.S. Geological Survey collected post-Hurricane Sandy oblique aerial photography and lidar topographic surveys to document the changes that occurred as a result of the storm. Comparisons of post-storm photographs to those collected prior to Sandy’s landfall were used to characterize the nature, magnitude, and spatial variability of hurricane-induced coastal changes. Analysis of pre- and post-storm lidar elevations was used to quantify magnitudes of change in shoreline position, dune elevation, and beach width. Erosion was observed along the coast from North Carolina to New York; however, as would be expected over such a large region, extensive spatial variability in storm response was observed.

Open-File Report

Coastal topography–Northeast Atlantic coast, post-hurricane Sandy, 2012

This Data Series contains lidar-derived bare-earth (BE) topography, dune elevations, and mean-high-water shoreline position datasets for most sandy beaches for Fire Island, New York, and from Cape Henlopen, Delaware to Cape Lookout, North Carolina. The data were acquired post-Hurricane Sandy, which made landfall as an extratropical cyclone on October 29, 2012.

Delaware, Maryland, New York, North Carolina, Virg

Environmental investigations using diatom microfossils

Diatoms are unicellular phytoplankton (microscopic plant-like organisms) with cell walls made of silica (called a frustule). They live in both freshwater and saltwater and can be found in just about every place on Earth that is wet. The shape and morphology of the diatom frustule unique to each species are used for identification. Due to the microscopic size of diatoms, high-power microscopy is required for diatom identification. Diatoms are vital to life on Earth. They are photosynthetic primary producers, using sunlight to create oxygen and organic carbon from carbon dioxide and water. They are a significant source of the oxygen we breathe, have a major impact on the global carbon cycle (Smetacek, 1999), and are a food source for many aquatic organisms (Mann, 1993). Diatom abundance has even been demonstrated to have an influence on the diversity of larger marine mammals, including whales (Marx and Uhen, 2010). Data on diatom abundance and diversity are extremely useful in environmental studies.

Fact Sheet

EAARL Coastal Topography - Northern Gulf of Mexico, 2007: First surface

These remotely sensed, geographically referenced elevation measurements of Lidar-derived first surface (FS) elevation data were produced as a collaborative effort between the U.S. Geological Survey (USGS), Florida Integrated Science Center (FISC), St. Petersburg, FL; the National Park Service (NPS), Gulf Coast Network, Lafayette, LA; and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. The project provides highly detailed and accurate datasets of select barrier islands and peninsular regions of Louisiana, Mississippi, Alabama, and Florida, acquired June 27-30, 2007. The datasets are made available for use as a management tool to research scientists and natural resource managers. An innovative airborne Lidar instrument originally developed at the NASA Wallops Flight Facility, and known as the Experimental Advanced Airborne Research Lidar (EAARL), was used during data acquisition. The EAARL system is a raster-scanning, waveform-resolving, green-wavelength (532-nanometer) Lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor suite includes the raster-scanning, water-penetrating full-waveform adaptive Lidar, a down-looking red-green-blue (RGB) digital camera, a high-resolution multi-spectral color infrared (CIR) camera, two precision dual-frequency kinematic carrier-phase GPS receivers, and an integrated miniature digital inertial measurement unit which provide for submeter georeferencing of each laser sample. The nominal EAARL platform is a twin-engine Cessna 310 aircraft, but the instrument may be deployed on a range of light aircraft. A single pilot, a Lidar operator, and a data analyst constitute the crew for most survey operations. This sensor has the potential to make significant contributions in measuring sub-aerial and submarine coastal topography within cross-environmental surveys. Elevation measurements were collected over the survey area using the EAARL system, and the resulting data were then processed using the Airborne Lidar Processing System (ALPS), a custom-built processing system developed in a NASA-USGS collaboration. ALPS supports the exploration and processing of Lidar data in an interactive or batch mode. Modules for presurvey flight line definition, flight path plotting, Lidar raster and waveform investigation, and digital camera image playback have been developed. Processing algorithms have been developed to extract the range to the first and last significant return within each waveform. ALPS is used routinely to create maps that represent submerged or sub-aerial topography. Specialized filtering algorithms have been implemented to determine the 'bare earth' under vegetation from a point cloud of last return elevations.

Alabama, Mississippi

EAARL coastal topography — Northern Gulf of Mexico, 2007: Bare earth

These remotely sensed, geographically referenced elevation measurements of Lidar -derived bare earth ( BE ) topography were produced as a collaborative effort between the U.S. Geological Survey ( USGS ), Florida Integrated Science Center ( FISC ), St. Petersburg, FL ; the National Park Service ( NPS ), Gulf Coast Network, Lafayette, LA ; and the National Aeronautics and Space Administration ( NASA ), Wallops Flight Facility, VA . The purpose of this project is to provide highly detailed and accurate datasets of select barrier islands and peninsular regions of Louisiana, Mississippi, Alabama, and Florida, acquired on June 27-30, 2007. The datasets are made available for use as a management tool to research scientists and natural resource managers. An innovative airborne Lidar instrument originally developed at the NASA Wallops Flight Facility, and known as the Experimental Advanced Airborne Research Lidar ( EAARL ), was used during data acquisition. The EAARL system is a raster-scanning, waveform-resolving, green-wavelength (532-nanometer) Lidar designed to map near-shore bathymetry, topography, and vegetation structure simultaneously. The EAARL sensor suite includes the raster-scanning, water-penetrating full-waveform adaptive Lidar , a down-looking red-green-blue ( RGB ) digital camera, a high-resolution multi-spectral color infrared ( CIR ) camera, two precision dual-frequency kinematic carrier-phase GPS receivers, and an integrated miniature digital inertial measurement unit which provide for submeter georeferencing of each laser sample. The nominal EAARL platform is a twin-engine Cessna 310 aircraft, but the instrument may be deployed on a range of light aircraft. A single pilot, a Lidar operator, and a data analyst constitute the crew for most survey operations. This sensor has the potential to make significant contributions in measuring sub-aerial and submarine coastal topography within cross-environmental surveys. Elevation measurements were collected over the survey area using the EAARL system and the resulting data were then processed using the Airborne Lidar Processing System ( ALPS ), a custom-built processing system developed in a NASA - USGS collaboration. ALPS supports the exploration and processing of Lidar data in an interactive or batch mode. Modules for presurvey flight line definition, flight path plotting, Lidar raster and waveform investigation, and digital camera image playback have been developed. Processing algorithms have been developed to extract the range to the first and last significant return within each waveform. ALPS is used routinely to create maps that represent submerged or sub-aerial topography. Specialized filtering algorithms have been implemented to determine the 'bare earth' under vegetation from a point cloud of last return elevations.

northern Gulf of Mexico

Topobathymetric data for Tampa Bay, Florida

Topobathymetric data (“topobathy”) are a merged rendering of both topography (land elevation) and bathymetry (water depth) to provide a single product useful for inundation mapping and a variety of other applications. These data were developed using one topographic and two bathymetric datasets collected at different dates. Topography was obtained from the U.S. Geological Survey's (USGS) National Elevation Dataset (NED). Bathymetry was provided by NOAA's GEOphysical DAta System (GEODAS). For several nearshore areas within the bay GEODAS data were replaced with high resolution bathymetry acquired by NASA's Experimental Advanced Airborne Research Lidar (EAARL).

Florida