Bruce Jaffe (Former Employee)
Science and Products
Filter Total Items: 13
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Filter Total Items: 86
A step decrease in sediment concentration in a highly modified tidal river delta following the 1983 El Niño floods
Anthropogenic activities in watersheds can have profound effects on sediment transport through river systems to estuaries. Disturbance in a watershed combined with alterations to the hydro-climatologic regime may result in changes to the sediment flux, and exacerbate the impacts of extreme events (such as large-magnitude floods) on sediment transport. In the San Francisco Estuary, suspended sedime
Authors
Erin L. Hestir, David H. Schoellhamer, Tara Morgan-King, Susan L. Ustin
The use of modeling and suspended sediment concentration measurements for quantifying net suspended sediment transport through a large tidally dominated inlet
Sediment exchange at large energetic inlets is often difficult to quantify due complex flows, massive amounts of water and sediment exchange, and environmental conditions limiting long-term data collection. In an effort to better quantify such exchange this study investigated the use of suspended sediment concentrations (SSC) measured at an offsite location as a surrogate for sediment exchange at
Authors
Li H. Erikson, Scott A. Wright, Edwin Elias, Daniel M. Hanes, David H. Schoellhamer, John Largier
A Sr-Nd isotopic study of sand-sized sediment provenance and transport for the San Francisco Bay coastal system
A diverse suite of geochemical tracers, including 87Sr/86Sr and 143Nd/144Nd isotope ratios, the rare earth elements (REEs), and select trace elements were used to determine sand-sized sediment provenance and transport pathways within the San Francisco Bay coastal system. This study complements a large interdisciplinary effort (Barnard et al., 2012) that seeks to better understand recent geomorphic
Authors
Robert J. Rosenbauer, Amy C. Foxgrover, James R. Hein, Peter W. Swarzenski
Sand sources and transport pathways for the San Francisco Bay coastal system, based on X-ray diffraction mineralogy
The mineralogical compositions of 119 samples collected from throughout the San Francisco Bay coastal system, including bayfloor and seafloor, area beaches, cliff outcrops, and major drainages, were determined using X-ray diffraction (XRD). Comparison of the mineral concentrations and application of statistical cluster analysis of XRD spectra allowed for the determination of provenances and transp
Authors
James R. Hein, Kira Mizell, Patrick L. Barnard
Distribution of biologic, anthropogenic, and volcanic constituents as a proxy for sediment transport in the San Francisco Bay Coastal System
Although conventional sediment parameters (mean grain size, sorting, and skewness) and provenance have typically been used to infer sediment transport pathways, most freshwater, brackish, and marine environments are also characterized by abundant sediment constituents of biological, and possibly anthropogenic and volcanic, origin that can provide additional insight into local sedimentary processes
Authors
Mary McGann, Li H. Erikson, Elmira Wan, Charles L. Powell, Rosalie F. Maddocks
Sediment transport in the San Francisco Bay Coastal System: An overview
The papers in this special issue feature state-of-the-art approaches to understanding the physical processes related to sediment transport and geomorphology of complex coastal-estuarine systems. Here we focus on the San Francisco Bay Coastal System, extending from the lower San Joaquin-Sacramento Delta, through the Bay, and along the adjacent outer Pacific Coast. San Francisco Bay is an urbanized
Authors
Patrick L. Barnard, David H. Schoellhamer, Bruce E. Jaffe, Lester J. McKee
Sediment transport patterns in the San Francisco Bay Coastal System from cross-validation of bedform asymmetry and modeled residual flux
The morphology of ~ 45,000 bedforms from 13 multibeam bathymetry surveys was used as a proxy for identifying net bedload sediment transport directions and pathways throughout the San Francisco Bay estuary and adjacent outer coast. The spatially-averaged shape asymmetry of the bedforms reveals distinct pathways of ebb and flood transport. Additionally, the region-wide, ebb-oriented asymmetry of 5%
Authors
Patrick L. Barnard, Li H. Erikson, Edwin P.L. Elias, Peter Dartnell
Seasonal variations in suspended-sediment dynamics in the tidal reach of an estuarine tributary
Quantifying sediment supply from estuarine tributaries is an important component of developing a sediment budget, and common techniques for estimating supply are based on gages located above tidal influence. However, tidal interactions near tributary mouths can affect the magnitude and direction of sediment supply to the open waters of the estuary. We investigated suspended-sediment dynamics in th
Authors
Maureen A. Downing-Kunz, David H. Schoellhamer
Sediment geochemistry of Corte Madera Marsh, San Francisco Bay, California: have local inputs changed, 1830-2010?
Large perturbations since the mid-1800s to the supply and source of sediment entering San Francisco Bay have disturbed natural processes for more than 150 years. Only recently have sediment inputs through the Sacramento-San Joaquin Delta (the Delta) decreased to what might be considered pre-disturbance levels. Declining sediment inputs to San Francisco Bay raise concern about continued tidal marsh
Authors
Renee K. Takesue, Bruce E. Jaffe
Geomorphic and stratigraphic evidence for an unusual tsunami or storm a few centuries ago at Anegada, British Virgin Islands
Waters from the Atlantic Ocean washed southward across parts of Anegada, east-northeast of Puerto Rico, during a singular event a few centuries ago. The overwash, after crossing a fringing coral reef and 1.5 km of shallow subtidal flats, cut dozens of breaches through sandy beach ridges, deposited a sheet of sand and shell capped with lime mud, and created inland fields of cobbles and boulders. Mo
Authors
Brian F. Atwater, Uri S. ten Brink, Mark Buckley, Robert S. Halley, Bruce E. Jaffe, Alberto M. López-Venegas, Eduard G. Reinhardt, Maritia P. Tuttle, Steve Watt, Yong Wei
Inland fields of dispersed cobbles and boulders as evidence for a tsunami on Anegada, British Virgin Islands
Marine overwash from the north a few centuries ago transported hundreds of angular cobbles and boulders tens to hundreds of meters southward from limestone outcrops in the interior of Anegada, 140 km east–northeast of Puerto Rico. We examined two of several cobble and boulder fields as part of an effort to interpret whether the overwash resulted from a tsunami or a storm in a location where both e
Authors
Bruce E. Jaffe, Steve Watt, Mark Buckley
Time-dependent onshore tsunami response
While bulk measures of the onshore impact of a tsunami, including the maximum run-up elevation and inundation distance, are important for hazard planning, the temporal evolution of the onshore flow dynamics likely controls the extent of the onshore destruction and the erosion and deposition of sediment that occurs. However, the time-varying dynamics of actual tsunamis are even more difficult to me
Authors
Alex Apotsos, Guy R. Gelfenbaum, Bruce E. Jaffe
Science and Products
Filter Total Items: 13
No Result Found
Filter Total Items: 86
A step decrease in sediment concentration in a highly modified tidal river delta following the 1983 El Niño floods
Anthropogenic activities in watersheds can have profound effects on sediment transport through river systems to estuaries. Disturbance in a watershed combined with alterations to the hydro-climatologic regime may result in changes to the sediment flux, and exacerbate the impacts of extreme events (such as large-magnitude floods) on sediment transport. In the San Francisco Estuary, suspended sedime
Authors
Erin L. Hestir, David H. Schoellhamer, Tara Morgan-King, Susan L. Ustin
The use of modeling and suspended sediment concentration measurements for quantifying net suspended sediment transport through a large tidally dominated inlet
Sediment exchange at large energetic inlets is often difficult to quantify due complex flows, massive amounts of water and sediment exchange, and environmental conditions limiting long-term data collection. In an effort to better quantify such exchange this study investigated the use of suspended sediment concentrations (SSC) measured at an offsite location as a surrogate for sediment exchange at
Authors
Li H. Erikson, Scott A. Wright, Edwin Elias, Daniel M. Hanes, David H. Schoellhamer, John Largier
A Sr-Nd isotopic study of sand-sized sediment provenance and transport for the San Francisco Bay coastal system
A diverse suite of geochemical tracers, including 87Sr/86Sr and 143Nd/144Nd isotope ratios, the rare earth elements (REEs), and select trace elements were used to determine sand-sized sediment provenance and transport pathways within the San Francisco Bay coastal system. This study complements a large interdisciplinary effort (Barnard et al., 2012) that seeks to better understand recent geomorphic
Authors
Robert J. Rosenbauer, Amy C. Foxgrover, James R. Hein, Peter W. Swarzenski
Sand sources and transport pathways for the San Francisco Bay coastal system, based on X-ray diffraction mineralogy
The mineralogical compositions of 119 samples collected from throughout the San Francisco Bay coastal system, including bayfloor and seafloor, area beaches, cliff outcrops, and major drainages, were determined using X-ray diffraction (XRD). Comparison of the mineral concentrations and application of statistical cluster analysis of XRD spectra allowed for the determination of provenances and transp
Authors
James R. Hein, Kira Mizell, Patrick L. Barnard
Distribution of biologic, anthropogenic, and volcanic constituents as a proxy for sediment transport in the San Francisco Bay Coastal System
Although conventional sediment parameters (mean grain size, sorting, and skewness) and provenance have typically been used to infer sediment transport pathways, most freshwater, brackish, and marine environments are also characterized by abundant sediment constituents of biological, and possibly anthropogenic and volcanic, origin that can provide additional insight into local sedimentary processes
Authors
Mary McGann, Li H. Erikson, Elmira Wan, Charles L. Powell, Rosalie F. Maddocks
Sediment transport in the San Francisco Bay Coastal System: An overview
The papers in this special issue feature state-of-the-art approaches to understanding the physical processes related to sediment transport and geomorphology of complex coastal-estuarine systems. Here we focus on the San Francisco Bay Coastal System, extending from the lower San Joaquin-Sacramento Delta, through the Bay, and along the adjacent outer Pacific Coast. San Francisco Bay is an urbanized
Authors
Patrick L. Barnard, David H. Schoellhamer, Bruce E. Jaffe, Lester J. McKee
Sediment transport patterns in the San Francisco Bay Coastal System from cross-validation of bedform asymmetry and modeled residual flux
The morphology of ~ 45,000 bedforms from 13 multibeam bathymetry surveys was used as a proxy for identifying net bedload sediment transport directions and pathways throughout the San Francisco Bay estuary and adjacent outer coast. The spatially-averaged shape asymmetry of the bedforms reveals distinct pathways of ebb and flood transport. Additionally, the region-wide, ebb-oriented asymmetry of 5%
Authors
Patrick L. Barnard, Li H. Erikson, Edwin P.L. Elias, Peter Dartnell
Seasonal variations in suspended-sediment dynamics in the tidal reach of an estuarine tributary
Quantifying sediment supply from estuarine tributaries is an important component of developing a sediment budget, and common techniques for estimating supply are based on gages located above tidal influence. However, tidal interactions near tributary mouths can affect the magnitude and direction of sediment supply to the open waters of the estuary. We investigated suspended-sediment dynamics in th
Authors
Maureen A. Downing-Kunz, David H. Schoellhamer
Sediment geochemistry of Corte Madera Marsh, San Francisco Bay, California: have local inputs changed, 1830-2010?
Large perturbations since the mid-1800s to the supply and source of sediment entering San Francisco Bay have disturbed natural processes for more than 150 years. Only recently have sediment inputs through the Sacramento-San Joaquin Delta (the Delta) decreased to what might be considered pre-disturbance levels. Declining sediment inputs to San Francisco Bay raise concern about continued tidal marsh
Authors
Renee K. Takesue, Bruce E. Jaffe
Geomorphic and stratigraphic evidence for an unusual tsunami or storm a few centuries ago at Anegada, British Virgin Islands
Waters from the Atlantic Ocean washed southward across parts of Anegada, east-northeast of Puerto Rico, during a singular event a few centuries ago. The overwash, after crossing a fringing coral reef and 1.5 km of shallow subtidal flats, cut dozens of breaches through sandy beach ridges, deposited a sheet of sand and shell capped with lime mud, and created inland fields of cobbles and boulders. Mo
Authors
Brian F. Atwater, Uri S. ten Brink, Mark Buckley, Robert S. Halley, Bruce E. Jaffe, Alberto M. López-Venegas, Eduard G. Reinhardt, Maritia P. Tuttle, Steve Watt, Yong Wei
Inland fields of dispersed cobbles and boulders as evidence for a tsunami on Anegada, British Virgin Islands
Marine overwash from the north a few centuries ago transported hundreds of angular cobbles and boulders tens to hundreds of meters southward from limestone outcrops in the interior of Anegada, 140 km east–northeast of Puerto Rico. We examined two of several cobble and boulder fields as part of an effort to interpret whether the overwash resulted from a tsunami or a storm in a location where both e
Authors
Bruce E. Jaffe, Steve Watt, Mark Buckley
Time-dependent onshore tsunami response
While bulk measures of the onshore impact of a tsunami, including the maximum run-up elevation and inundation distance, are important for hazard planning, the temporal evolution of the onshore flow dynamics likely controls the extent of the onshore destruction and the erosion and deposition of sediment that occurs. However, the time-varying dynamics of actual tsunamis are even more difficult to me
Authors
Alex Apotsos, Guy R. Gelfenbaum, Bruce E. Jaffe