Christopher G. Smith, Ph.D.
As a coastal geologist, my research focuses on the transport, transformation, and deposition of particulate and dissolved constituents within the coastal realm and how system processes will respond to large-scale environmental forcings (e.g., climate change).
Coastal systems provide a dynamic interface between terrestrial and marine realms; anthropogenic activity and natural processes occurring within terrestrial ecosystems can have a significant impact to the coastal zone and adjacent marine system. Augmentation of coastal systems is inevitable from a human perspective as nearly half of the population of the United States reside within coastal counties. Understanding modern processes (sedimentologic, hydrologic, and geochemical) occurring along this terrestrial-marine continuum is critical in predicting the response associated with natural and anthropogenic perturbations.
My research interests generally fall into two categories: 1) fluid exchange (e.g., surface water – groundwater exchange, submarine and coastal groundwater discharge) and 2) fine-grained sediment dynamics, specifically in marsh and estuarine environments. Linking these two seemingly disparate research topics are naturally-occurring (e.g., U-Th series) and anthropogenically-introduced/spiked (e.g., 137Cs) radionuclides. Particle reactive radionuclides (e.g., 7Be, 234Th, 210Pb, 210Po, and 137Cs) provide excellent tracers to quantify sediment deposition and re-mobilization over time-scales of months to decades. Examining the final sedimentary product in the context of the temporal framework and associated transient changes also provide a breadth of knowledge to environmental conditions that persisted in recent past and the outcome that may be expected if similar conditions persist in the present or future. Alternatively, the more conservative behavior of radon and radium isotopes have proven these as excellent tracers to quantify groundwater discharge in both fresh and marine environments.
Over the last three decades, groundwater discharge to the coastal zone has received increasing recognition as a substantial material vector, influencing water quality and nutrient fluxes. Quantification of fresh and marine groundwater end-members and the processes that drive the exchange (e.g., seasonal recharge cycles, hurricanes and tropical cyclones) are critical to assess the overall importance of coastal groundwater and has been at the forefront of my research.
Professional Experience
2010-Present: Research Geologist, USGS, St. Petersburg Coastal and Marine Science Center
2008 - 2010: USGS Mendenhall Fellow, St. Petersburg Coastal and Marine Science Center
Education and Certifications
PhD - Oceanography & Coastal Science (Geological conc) (2008) from Louisiana State University (Geaux Tigers!)
MS - Geology (2004) from East Carolina University
BS - Geology (2001) from East Carolina University (NC)
Science and Products
Benthic Foraminiferal Data from Sedimentary Cores Collected in the Grand Bay (Mississippi) and Dauphin Island (Alabama) Salt Marshes
Benthic Foraminiferal Data from the Eastern Mississippi Sound Salt Marshes and Estuaries
Single-Beam Bathymetry Data Collected in 2015 from Grand Bay, Mississippi/Alabama
Radon-222 and Physical Water Column Parameter Data Concerning Submarine Groundwater Discharge Along the Western Margin of Indian River Lagoon, East-Central Florida-September 2016 to July 2017
Radon-222 and Water Column Data Related to Submarine Groundwater Discharge Along the Western Margin of Indian River Lagoon, Florida-September 2017 and November 2017
The Sedimentological Characteristics and Radiochemistry Data for the Marshes on Dauphin Island, Alabama
Sedimentary Data from the Coastal Marshes Fringing the Lower Waccasassa River, Northwest Florida
Seasonal Sedimentary Data Collected from Old Tampa Bay, Florida, 2015-2016
Archive of Sediment Physical Properties and Grain-Size Data for Sediment Samples Collected Offshore of Assateague Island, Maryland and Virginia
Vector Shorelines and Associated Shoreline Change Rates Derived from Lidar and Aerial Imagery for Dauphin Island, Alabama: 1940-2015
Hydrological Data Concerning Submarine Groundwater Discharge along the Western Margin of Indian River Lagoon, East-central Florida - December 2016 and January 2017
The magnitude and origin of groundwater discharge to eastern U.S. and Gulf of Mexico coastal waters
Sediment lithology and radiochemistry from the back-barrier environments along the northern Chandeleur Islands, Louisiana—March 2012
Application of ground penetrating radar for identification of washover deposits and other stratigraphic features: Assateague Island, MD
Observations of nearshore groundwater discharge: Kahekili Beach Park submarine springs, Maui, Hawaii
Ground-penetrating radar and differential global positioning system data collected from Long Beach Island, New Jersey, April 2015
The role of ocean tides on groundwater-surface water exchange in a mangrove-dominated estuary: Shark River Slough, Florida Coastal Everglades, USA
Evaluating the potential effects of hurricanes on long-term sediment accumulation in two micro-tidal sub-estuaries: Barnegat Bay and Little Egg Harbor, New Jersey, U.S.A.
Raw and processed ground-penetrating radar and postprocessed differential global positioning system data collected from Assateague Island, Maryland, October 2014
Sedimentologic characteristics of recent washover deposits from Assateague Island, Maryland
Archive of ground penetrating radar data collected during USGS field activity 13BIM01—Dauphin Island, Alabama, April 2013
A seasonal comparison of surface sediment characteristics in Chincoteague Bay, Maryland and Virginia, USA
Land-cover types, shoreline positions, and sand extents derived From Landsat satellite imagery, Assateague Island to Metompkin Island, Maryland and Virginia, 1984 to 2014
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
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Filter Total Items: 35
Benthic Foraminiferal Data from Sedimentary Cores Collected in the Grand Bay (Mississippi) and Dauphin Island (Alabama) Salt Marshes
Microfossil (benthic foraminifera) data from coastal areas were collected from state and federally managed lands within the Grand Bay National Estuarine Research Reserve and Grand Bay National Wildlife Refuge, Grand Bay, Mississippi/Alabama; federally managed lands of Bon Secour National Wildlife Refuge on Cedar Island and Little Dauphin Island, Alabama; and municipally managed land around DauphinBenthic Foraminiferal Data from the Eastern Mississippi Sound Salt Marshes and Estuaries
Microfossil (benthic foraminifera) and coordinate/elevation data were obtained from sediments collected in the coastal zones of Mississippi and Alabama, including marsh and estuarine environments of eastern Mississippi Sound and Mobile Bay, in order to develop a census for coastal environments and to aid in paleoenvironmental reconstruction. These data provide a baseline dataset for use in futureSingle-Beam Bathymetry Data Collected in 2015 from Grand Bay, Mississippi/Alabama
This data release archives processed single-beam bathymetry (SBB) data, collected from May 28-June 3, 2015 (USGS Field Activity Number 2015-315-FA) within Grand Bay Mississippi/Alabama, as part of the Sea level and Storm Impacts on Estuarine Environments and Shorelines project (SSIEES). The goal of the SSIEES project is to assess the physical controls of sediment and material exchange between wetlRadon-222 and Physical Water Column Parameter Data Concerning Submarine Groundwater Discharge Along the Western Margin of Indian River Lagoon, East-Central Florida-September 2016 to July 2017
Indian River Lagoon (IRL) is one of the most biologically diverse estuarine systems in the continental United States, stretching 200 kilometers (km) along the Atlantic coast of central Florida. The width of the lagoon varies between 0.5-9.0 km and is characterized by shallow, brackish waters with significant human development along both shores. Scientists from the U.S. Geological Survey (USGS) StRadon-222 and Water Column Data Related to Submarine Groundwater Discharge Along the Western Margin of Indian River Lagoon, Florida-September 2017 and November 2017
Indian River Lagoon (IRL) is one of the most biologically diverse estuarine systems in the continental United States, extending 200 kilometers (km) along the Atlantic coast of central Florida. The lagoon is characterized by shallow, brackish waters with significant human development along both shores and a width that varies between 0.5-9.0 km. Scientists from the U.S. Geological Survey (USGS) St.The Sedimentological Characteristics and Radiochemistry Data for the Marshes on Dauphin Island, Alabama
Scientists from the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center collected push cores from the marshes of Dauphin Island, Little Dauphin Island, and Cedar Key, Alabama in August, 2015 (U.S. Geological Survey Field Activity Number 2015-322-FA). Sample sites varied between high marshes, low salt marshes, and sand flats. This report serves as an archive for the sedimentoloSedimentary Data from the Coastal Marshes Fringing the Lower Waccasassa River, Northwest Florida
The Waccasassa River is located in a small watershed situated along the middle section of the low-gradient, low-energy, sediment-starved Big Bend coast in west central Florida. The river mouth empties into the head of the shallow, microtidal Waccasassa Bay and the Gulf of Mexico. The lower end of the river and the surrounding coastline are dominated by coast-parallel Juncus roemerianus salt marsheSeasonal Sedimentary Data Collected from Old Tampa Bay, Florida, 2015-2016
The toxic dinoflagellate Pyrodinium bahamense produces recurring, persistent summer algal blooms in Old Tampa Bay, Florida, which degrade water quality and are potentially harmful to humans if contaminated shellfish is consumed. As part of its life cycle, Pyrodinium bahamense produces dormant cysts, which settle to the seafloor, forming seed beds that may initiate future blooms if favorable conditArchive of Sediment Physical Properties and Grain-Size Data for Sediment Samples Collected Offshore of Assateague Island, Maryland and Virginia
This data release serves as an archive of sediment physical properties and grain-size data for surficial samples collected offshore of Assateague Island, Maryland and Virginia, for comparison with surficial estuarine and subaerial sedimentological samples collected and assessed following Hurricane Sandy (Ellis and others, 2015; Smith and others, 2015; Bernier and others, 2016). The sediment sampleVector Shorelines and Associated Shoreline Change Rates Derived from Lidar and Aerial Imagery for Dauphin Island, Alabama: 1940-2015
In support of studies and assessments of barrier island evolution in the Gulf of Mexico, rates of shoreline change for Dauphin Island, Alabama, were calculated using two different shoreline proxy datasets with a total temporal span of 75 years. Mean High Water line (MHW) shorelines were generated from 14 lidar datasets from 1998 to 2014, and Wet Dry Line (WDL) shorelines were digitized from ten sHydrological Data Concerning Submarine Groundwater Discharge along the Western Margin of Indian River Lagoon, East-central Florida - December 2016 and January 2017
Indian River Lagoon, one of the most biologically diverse estuarine systems in the continental United States, is a shallow brackish lagoon stretching along approximately 200 kilometers (km) of the Atlantic coast of central Florida. Lagoon width varies from ~0.5 - 9.0 km, with substantial human infrastructure lining both shores. Scientists from the U.S. Geological Survey (USGS) St. Petersburg Coast - Multimedia
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The magnitude and origin of groundwater discharge to eastern U.S. and Gulf of Mexico coastal waters
Fresh groundwater discharge to coastal environments contributes to the physical and chemical conditions of coastal waters, but the role of coastal groundwater at regional to continental scales remains poorly defined due to diverse hydrologic conditions and the difficulty of tracking coastal groundwater flow paths through heterogeneous subsurface materials. We use three-dimensional groundwater flowAuthorsKevin Befus, Kevin D. Kroeger, Christopher G. Smith, Peter W. SwarzenskiSediment lithology and radiochemistry from the back-barrier environments along the northern Chandeleur Islands, Louisiana—March 2012
Scientists from the U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center collected a set of 8 sediment cores from the back-barrier environments along the northern Chandeleur Islands, Louisiana, in March 2012. The sampling efforts were part of a larger USGS study to evaluate effects on the geomorphology of the Chandeleur Islands following the construction of an artificialAuthorsMarci E. Marot, Christopher G. Smith, C. Scott Adams, Kathryn A. RichwineApplication of ground penetrating radar for identification of washover deposits and other stratigraphic features: Assateague Island, MD
A combination of ground penetrating radar (GPR) data, core data, and aerial photographs were analyzed to better understand the evolution of two portions of Assateague Island, Maryland. The focus of the study was to investigate the applicability of using GPR data to image washover deposits in the stratigraphic record. High amplitude reflections observed in two shore-perpendicular GPR profiles wereAuthorsNicholas Zaremba, Christopher G. Smith, Julie Bernier, Arnell S. FordeObservations of nearshore groundwater discharge: Kahekili Beach Park submarine springs, Maui, Hawaii
Study regionThe study region encompasses the nearshore, coastal waters off west Maui, Hawaii. Here abundant groundwater—that carries with it a strong land-based fingerprint—discharges into the coastal waters and over a coral reef.Study focusCoastal groundwater discharge is a ubiquitous hydrologic feature that has been shown to impact nearshore ecosystems and material budgets. A unique combined geoAuthorsPeter W. Swarzenski, H. Dulai, K.D. Kroeger, C.G. Smith, N. Dimova, C. D. Storlazzi, N.G. Prouty, S. B. Gingerich, C. R. GlennGround-penetrating radar and differential global positioning system data collected from Long Beach Island, New Jersey, April 2015
Scientists from the United States Geological Survey, St. Petersburg Coastal and Marine Science Center, U.S. Geological Survey Pacific Coastal and Marine Science Center, and students from the University of Hawaii at Manoa collected sediment cores, sediment surface grab samples, ground-penetrating radar (GPR) and Differential Global Positioning System (DGPS) data from within the Edwin B. Forsythe NaAuthorsNicholas J. Zaremba, Kathryn E.L. Smith, James M. Bishop, Christopher G. SmithThe role of ocean tides on groundwater-surface water exchange in a mangrove-dominated estuary: Shark River Slough, Florida Coastal Everglades, USA
Low-relief environments like the Florida Coastal Everglades (FCE) have complicated hydrologic systems where surface water and groundwater processes are intimately linked yet hard to separate. Fluid exchange within these lowhydraulic-gradient systems can occur across broad spatial and temporal scales, with variable contributions to material transport and transformation. Identifying and assessing thAuthorsChristopher G. Smith, René M. Price, Peter W. Swarzenski, Jeremy C. StalkerEvaluating the potential effects of hurricanes on long-term sediment accumulation in two micro-tidal sub-estuaries: Barnegat Bay and Little Egg Harbor, New Jersey, U.S.A.
Barnegat Bay, located along the eastern shore of New Jersey, was significantly impacted by Hurricane Sandy in October 2012. Scientists from the U.S. Geological Survey (USGS) developed a multidisciplinary study of sediment transport and hydrodynamics to understand the mechanisms that govern estuarine and wetland responses to storm forcing. This report details the physical and chemical characteristiAuthorsMarci E. Marot, Christopher G. Smith, Alisha M. Ellis, Cathryn J. WheatonRaw and processed ground-penetrating radar and postprocessed differential global positioning system data collected from Assateague Island, Maryland, October 2014
Scientists from the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center acquired sediment cores, sediment surface grab samples, ground-penetrating radar (GPR) and Differential Global Positioning System (DGPS) data from Assateague Island, Maryland, in October 2014. The objectives were to identify washover deposits in the stratigraphic record to aid in understanding barrier islaAuthorsNicholas J. Zaremba, Julie Bernier, Arnell S. Forde, Christopher G. SmithSedimentologic characteristics of recent washover deposits from Assateague Island, Maryland
The U.S. Geological Survey has a long history of responding to and documenting the impacts of storms along the Nation’s coasts and incorporating these data into storm impact and coastal change vulnerability assessments. Although physical changes caused by tropical and extratropical storms to the sandy beaches and dunes fronting barrier islands are generally well documented, the interaction betweenAuthorsJulie Bernier, Nicholas J. Zaremba, Cathryn J. Wheaton, Alisha M. Ellis, Marci E. Marot, Christopher G. SmithArchive of ground penetrating radar data collected during USGS field activity 13BIM01—Dauphin Island, Alabama, April 2013
From April 13 to 20, 2013, scientists from the U.S. Geological Survey St. Petersburg Coastal and Marine Science Center (USGS-SPCMSC) conducted geophysical and sediment sampling surveys on Dauphin Island, Alabama, as part of Field Activity 13BIM01. The objectives of the study were to quantify inorganic and organic accretion rates in back-barrier and mainland marsh and estuarine environments. VariouAuthorsArnell S. Forde, Christopher G. Smith, Billy J. ReynoldsA seasonal comparison of surface sediment characteristics in Chincoteague Bay, Maryland and Virginia, USA
Scientists from the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center conducted a seasonal collection of surficial sediments from Chincoteague Bay and Tom's Cove, between Assateague Island and the Delmarva Peninsula in late March/early April 2014 and October 2014. The sampling efforts were part of a larger U.S. Geological Survey study to assess the effects of storm events onAuthorsAlisha M. Ellis, Marci E. Marot, Cathryn J. Wheaton, Julie Bernier, Christopher G. SmithLand-cover types, shoreline positions, and sand extents derived From Landsat satellite imagery, Assateague Island to Metompkin Island, Maryland and Virginia, 1984 to 2014
The U.S. Geological Survey has a long history of responding to and documenting the impacts of storms along the Nation’s coasts and incorporating these data into storm impact and coastal change vulnerability assessments. These studies, however, have traditionally focused on sandy shorelines and sandy barrier-island systems, without consideration of impacts to coastal wetlands. The goal of the BarriAuthorsJulie Bernier, Steven H. Douglas, Joseph F. Terrano, John A. Barras, Nathaniel G. Plant, Christopher G. SmithNon-USGS Publications**
Cable, J.E., Smith, C.G., Blanford, W.J. 2009. Dispersivity and distribution coefficients in marine sediments using Tritium and Radium-226. Radioprotection, 44:185-190.Smith, C.G., Cable, J.E., Martin, J.B., and Roy, M. 2008. Evaluating the source and seasonality of submarine groundwater discharge using a Radon-222 pore water transport model, Earth and Planetary Science Letters 273:312-322.Culver, S.J., Grand Pre, C., Mallinson, D., Riggs, S., Corbett, D.R., Foley, J., Hale, M., Ricardo, J., Rosenberger, J., Smith, C.G., Smith, C.W., Snyder, S., Twamley, D., Farrell, K., Horton, B. 2007. Late Holocene barrier island collapse: Outer Banks, North Carolina, U.S.A. The Sedimentary Record 5:4-8.Smith, C.G., Cable, J.E., Martin, J.B. 2008. Episodic high intensity mixing events in a subterranean estuary: Effects of tropical cyclones, Limnology and Oceanography 53:666-674.Smith, C.G., Culver, S.J., Riggs, S.R., Ames, D., Corbett, D.R., Mallinson, D.J. 2008. Geospatial analysis of barrier island width of two segments of the Outer Banks, North Carolina, USA: anthropogenic curtailment of natural self-sustaining processes. Journal of Coastal Research 24:70-83.Martin, J.B., Cable, J., Smith, C.G., Roy, M. and Cherrier, J. 2007. Magnitudes of submarine groundwater discharge from marine and terrestrial sources: Indian River Lagoon, Florida. Water Resources Research 43: doi:10.1029/2006WR005266.Smith, C.G., Cable, J.E., Martin, J.B., Cherrier, J., and Roy, M. 2006. Mixing in the subterranean estuary: a comparison of Radon-222 pore water models. p. 355-368, In V. P. Singh and Y. J. Xu [eds.], Annual American Institute of Hydrology Meeting & International Conference: Challenges in Coastal Hydrology and Water Quality. Water Resources Publications, LLC, 534 pp.Martin, J.B., Cable, J.E., Jaeger, J., Hartl, K.M., and Smith, C.G. 2006. Thermal and chemical evidence for rapid water exchange across the sediment-water interface by bioirrigation in the Indian River Lagoon, Florida. Limnology and Oceanography 51:1332-1341.Culver, S.J., Ames, D.V., Corbett, D.R., Malllinson, D., Riggs, S.R., Smith, C.G., and Vance, D. 2005. Foraminiferal and sedimentary record of late Holocene barrier island evolution, Pea Island, North Carolina. Journal of Coastal Research 21:406-416.**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
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