Stephen B DeLong, Ph.D.
I am a Supervisory Research Geologist in the USGS Earthquake Science Center. My primary focus is characterizing earthquake hazard in northern California. To do this I apply fieldwork, geochronology, remote sensing, and a range of quantitative methods to zones of active crustal deformation.
I also collaborate on a wide range of projects that involve lidar and photogrammetric data acquisition, processing, and analysis. My group maintains a wide range of hardware and software for acquiring and processing high-resolution topographic data.
Education
Ph.D. University of Arizona, Tucson AZ, 2006, Geosciences
B.S. University of Minnesota Duluth, Duluth MN, 1997 cum laude Major: Geology; Minor: Chemistry
Professional Summary
U.S. Geological Survey, Earthquake Science Center, Supervisory Research Geologist, 2016 –
U.S. Geological Survey, Earthquake Science Center, Research Geologist, 2013 – 2016
University of Minnesota, Department of Earth Sciences, Graduate Faculty, 2016 - present
University of Arizona, Biosphere 2, Assistant Research Professor and Biosphere 2 Landscape Evolution Observatory lead scientist, March 2010 – February 2013
University of Arizona, Department of Geosciences, Assistant Research Professor (Joint), March 2010 – 2013
United States Geological Survey Mendenhall Postdoctoral Fellow, USGS Earthquake Science Center- Menlo Park, CA, October 2008 - August 2010
Postdoctoral Research Associate, Arizona State University, Tempe, AZ, Aug 2007-October 2008
Visiting Assistant Professor, Cornell College, Mount Vernon, IA, August 2006-May 2007
Research Assistant, Los Alamos National Laboratory, 2005-2006 Yucca Mountain Project Igneous Hazards Team
Teaching/Research Assistant, University of Arizona, Tucson, AZ, 2002-2005
Geologist, United States Geological Survey, Tucson, AZ, summer 2002
Geologist, Arizona Geological Survey, Tucson, AZ, 2002-2005
Science and Products
Exploiting high-resolution topography for advancing the understanding of mass and energy transfer across landscapes: Opportunities, challenges, and needs
One of the grand challenges of Earth Surface Science and Natural Resource Management lies in the prediction of mass and energy transfer for large watersheds and landscapes. High resolution topography (lidar) datasets show potential to significantly advance our understanding of hydrologic and geomorphic processes controlling mass and energy transfer because they represent features at the...
Filter Total Items: 20
Datasets documenting late Pleistocene faulting in the Pondosa fault zone, Pit River Region, Northeastern California
These datasets provide bedrock mapping and geochemistry, low-temperature thermochronology, remotely mapped lineaments, field observations of interpreted faults, and structure from motion models in the Pit River Region of northeastern California. The bedrock mapping datasets contain bedding orientations and field rock descriptions and associated geochemistry and 40Ar/39Ar data for a...
Earthquake geology inputs for the National Seismic Hazard Model (NSHM) 2025 (Puerto Rico and U.S. Virgin Islands), version 1.0
This Data Release contains preliminary versions of three related geologic input databases for the Puerto Rico and U.S. Virgin Islands (PRVI) region (62°–70° W and 16°–21° N) of the United States: 1) A fault sections database (“NSHM2025_FaultSections_PRVI_v1’”), which depicts the geometry of faults capable of hosting independent earthquakes, 2) a fault-zone polygon database ("NSHM2025...
Digital elevation and point cloud data from laser scanning at the Gualala paleoseismic site along the San Andreas Fault
These data are derived from laser scanning surveys of a paleoseismic investigation site along the north coast section of the San Andreas Fault near Gualala, CA. We performed three surveys with a terrestrial laser scanner at different stages of trench excavation in 2021. To generate more complete maps of the bare ground at the site, we also incorporated airborne laser scanner data from...
Earthquake geology inputs for the U.S. National Seismic Hazard Model (NSHM) 2023 (western U.S.) (ver. 3.0, December 2023)
This Data Release contains version 3.0 of two related earthquake geology databases for use in the 2023 U.S. National Seismic Hazard Model. The databases are: 1) A fault sections database (“NSHM23_FSD_v3”), which depicts the geometry of faults capable of hosting independent earthquakes, and 2) an earthquake geology site information database (“NSHM23_EQGeoDB_v3”), which contains fault slip...
High-resolution seismic imaging data acquired in 2021 across the West Winters Fault, Great Valley Fault System at Bigelow Hills, Yolo County, California
In June of 2021, the U.S. Geological Survey conducted a high-resolution seismic survey at Winters, California. Seismic data were acquired using a DTCC SmartSolo 3-component nodal seismograph system ("node"), which continuously recorded at 2000 samples per second. Nodes were deployed 5 meters apart from west-southwest to east-northeast to create an approximately 800-m-long linear profile...
Suspended sediment and bedload data, simple linear regression models, loads, elevation data, and FaSTMECH models for Rice Creek, Minnesota, 2010-2019
A series of simple linear regression models were developed for the U.S. Geological Survey (USGS) streamgage at Rice Creek below Highway 8 in Mounds View, Minnesota (USGS station number 05288580). The simple linear regression models were calibrated using streamflow data to estimate suspended-sediment (total, fines, and sands) and bedload. Data were collected during water years 2010, 2011...
Earthquake geology inputs for the U.S. National Seismic Hazard Model (NSHM) 2023 (western US) (ver. 2.0, February 2022)
This Data Release contains preliminary versions of two related databases: 1) A fault sections database ('NSHM23_FSD_v2'), which depicts the geometry of faults capable of hosting independent earthquakes, and 2) An earthquake geology site information database ('NSHM23_EQGeoDB_v2'), which contains fault slip-rate constraints at points. These databases were prepared in anticipation of...
Inventory of landslides in the northwestern, northeastern, southern, and southeastern parts of Minnesota
This dataset contains an inventory of landslides in many of the most landslide-prone parts of Minnesota. This project was created to improve our understanding of the landslide hazard in Minnesota and to provide a nearly statewide base map of landslide data. The mapping was performed by geologists from the U.S. Geological Survey, the Freshwater Society, and several academic institutions...
Raster and mapping data indicating landscape change from the June 2012 storm in the Duluth, MN region
The GeoTiff raster data were created from subtraction of elevation values collected in 2012 from elevation values collected in 2011. Both data collections were conducted by airborne lidar surveys contracted by the Minnesota Department of Natural Resources. These survey occured before and after a historical rain event that cause widespread landscape change. The shapefiles are polygon...
Reclassified lidar point cloud data from 2016 LARIAC and 2019 NCALM collections covering part of the Woolsey wildfire near Malibu, California
These lidar data are derived from two airborne lidar surveys: a 2016 Los Angeles Region Imagery Acquisition Consortium (LARIAC) survey, and a 2019 National Center for Airborne Laser Mapping (NCALM) survey. These data were reclassified in order to improve the classification of ground points, and to make the classification of both datasets as consistent as possible. The NCALM data had...
Lidar point cloud, GNSS, and raster data from near St. Helena, CA, March 30 and August 1, 2017
Text files: These data are text files of GNSS survey points collected along a trace of the West Napa Fault Zone near Ehler?s Lane north of St. Helena, California. Data were collected to aid in paleoseismic investigation of the suspected fault strand and to characterize local geomorphology. Data were collected on March 31, and August 1, 2017 using a Leica Viva GS15 survey grade GPS. The...
Earthquake geology inputs for the U.S. National Seismic Hazard Model (NSHM) 2023, version 1.0
This Data Release contains preliminary versions of two related databases: 1) A fault sections database ("NSHM2023_FaultSections_v1"), which depicts the geometry of faults capable of hosting independent earthquakes, and 2) An earthquake geology site information database ("NSHM2023_EQGeoDB_v1"), which contains fault slip-rate constraints at points. These databases were prepared in...
Filter Total Items: 30
Evaluating post-wildfire debris-flow rainfall thresholds and volume models at the 2020 Grizzly Creek Fire in Glenwood Canyon, Colorado, USA
As wildfire increases in the western United States, so do postfire debris-flow hazards. The U.S. Geological Survey (USGS) has developed two separate models to estimate (1) rainfall intensity thresholds for postfire debris-flow initiation and (2) debris-flow volumes. However, the information necessary to test the accuracy of these models is seldom available. Here, we studied how well...
Authors
Francis K. Rengers, Samuel Bower, Andrew Knapp, Jason W. Kean, Danielle W. vonLembke, Matthew A. Thomas, Jaime Kostelnik, Katherine R. Barnhart, Matthew Bethel, Joseph E. Gartner, Madeline Hille, Dennis M. Staley, Justin K. Anderson, Elizabeth K. Roberts, Stephen B. DeLong, Belize Lane, Paxton Ridgeway, Brendan Murphy
Sediment monitoring and streamflow modeling before and after a stream restoration in Rice Creek, Minnesota, 2010–2019
The Rice Creek Watershed District (RCWD) cooperated with the U.S. Geological Survey to establish a 10-year suspended sediment and bedload monitoring and streamflow modeling study to evaluate the effects of two restored meander sections on middle Rice Creek in Arden Hills, Minnesota. The RCWD goals of this stream restoration were to reduce water quality impairments, improve aquatic...
Authors
Joel T. Groten, Colin T. Livdahl, Stephen B. DeLong, J. William Lund, Jonathan M. Nelson, Erin N. Coenen, Jeffrey R. Ziegeweid, Matthew J. Kocian
Landslides in Minnesota
Landslides in Minnesota have caused loss of life, damaged infrastructure, and negatively affected Minnesota’s natural resources. Landslides increase the amount of sediment contributed to lakes and rivers, with negative consequences for water quality and aquatic habitats. Recent mapping reveals that landslide susceptible areas within Minnesota primarily occur on steep slopes adjacent to...
Authors
Stephen B. DeLong, Carrie E. Jennings, Karen B. Gran
Streambank erosion and related geomorphic change in Tuolumne Meadows, Yosemite National Park, California
Landscape change in Tuolumne Meadows, Yosemite National Park, California, was characterized using data derived from four lidar surveys: one airborne survey in 2006 and three terrestrial surveys in 2016, 2017, and 2018. These surveys were used to generate a better quantitative understanding of changes associated with fluvial processes along the reach of the Tuolumne River within Tuolumne...
Authors
Stephen B. DeLong, Alexandra J. Pickering, Timothy Kuhn
Rapid strain release on the Bear River fault zone, Utah–Wyoming—The impact of preexisting structure on the rupture behavior of a new normal fault
Earthquake clustering (grouping in space and time) is a widely observed mode of strain release in the upper crust, although this behavior on individual faults is a departure from classic elastic rebound theory. In this study, we consider factors responsible for a cluster of earthquakes on the Bear River fault zone (BRF), a recently activated, 44-km-long normal fault on the eastern margin...
Authors
Suzanne Hecker, David P. Schwartz, Stephen B. DeLong
Distribution of aseismic deformation along the central San Andreas and Calaveras Faults from differencing repeat airborne lidar
Fault creep reduces seismic hazard and serves as a window into plate boundary processes; however, creep rates are typically constrained with sparse measurements. We use differential lidar topography (11–13 year time span) to measure a spatially dense surface deformation field along a 150 km section of the Central San Andreas and Calaveras faults. We use an optimized windowed‐iterative...
Authors
Chelsea P Scott, Stephen B. DeLong, J Ramon Arrosmith
Documentation of Surface Fault Rupture and Ground‐Deformation Features Produced by the 4 and 5 July 2019 Mw 6.4 and Mw 7.1 Ridgecrest Earthquake Sequence
The MwMw 6.4 and MwMw 7.1 Ridgecrest earthquake sequence occurred on 4 and 5 July 2019 within the eastern California shear zone of southern California. Both events produced extensive surface faulting and ground deformation within Indian Wells Valley and Searles Valley. In the weeks following the earthquakes, more than six dozen scientists from government, academia, and the private sector...
Authors
Daniel J. Ponti, James Luke Blair, Rosa Carla M, Kate Thomas, Alexandra Pickering, Sinan Akciz, Stephen J. Angster, Jean-Philipe Avouac, Jeffrey Bachhuber, Steven Bacon, Nicolas C. Barth, S. Bennett, Kelly Blake, Stephan Bork, Benjamin A. Brooks, Thomas Bullard, Paul A. Burgess, Colin Chupik, Timothy E. Dawson, Michael DeFrisco, Jaime E. Delano, Stephen B. DeLong, James D. Dolan, Andrea Donnellan, Christopher DuRoss, Todd Ericksen, Erik Frost, Gareth J. Funning, Ryan D. Gold, Nicholas A Graehl, Carlos Gutierrez, Elizabeth Haddon, Alexandra Elise Hatem, John Helms, Janis Hernandez, Christopher S. Hitchcock, Peter Holland, Kenneth W. Hudnut, Katherine J. Kendrick, Richard D Koehler, Ozgur Kozaci, Tyler C. Ladinsky, Robert Leeper, Christopher Madugo, Maxime Mareschal, James McDonald, Devin McPhillips, Christopher Milliner, Daniel Mongovin, Alexander Morelan, Stephanie Nale, Johanna Nevitt, Matt O'Neal, Brian J. Olsen, Michael Oskin, Salena Padilla, Jason Patton, Belle E. Philibosian, Ian Pierce, Cynthia Pridmore, Nathaniel Roth, David Sandwell, Katherine M. Scharer, Gordon G. Seitz, Drake Singleton, Bridget Smith-Konter, Eleanor Spangler, Brian J. Swanson, Jessica Thompson Jobe, Jerome Treiman, Francesca Valencia, Joshua Vanderwal, Alana Williams, Xiaohua Xu, Judith Zachariasen, Jade Zimmerman, Robert Zinke
Landscape change associated with the upper Scenic Drive landslide, La Honda, California, January 10–June 28, 2017
La Honda, California, is a small town in unincorporated San Mateo County, located on the west edge of the San Francisco Peninsula in the Santa Cruz Mountains, between San Francisco and San Jose. The Scenic Drive area of La Honda has experienced several past episodes of landslide motion, which were documented in 1998, 2005, and 2006. This report documents the movement of the upper Scenic...
Authors
Alexandra J. Pickering, Carol S. Prentice, Stephen B. DeLong
Post-wildfire landscape change and erosional processes from repeat terrestrial lidar in a steep headwater catchment, Chiricahua Mountains, Arizona, USA
Flooding and erosion after wildfires present increasing hazard as climate warms, semi-arid lands become drier, population increases, and the urban interface encroaches farther into wildlands. We quantify post-wildfire erosion in a steep, initially unchannelized, 7.5 ha headwater catchment following the 2011 Horseshoe 2 Fire in the Chiricahua Mountains of southeastern Arizona. Using time...
Authors
Stephen B. DeLong, Ann M. Youberg, Whitney M. DeLong, Brendan P. Murphy
Spatio-temporal mapping of plate boundary faults in California using geodetic imaging
The Pacific–North American plate boundary in California is composed of a 400-km-wide network of faults and zones of distributed deformation. Earthquakes, even large ones, can occur along individual or combinations of faults within the larger plate boundary system. While research often focuses on the primary and secondary faults, holistic study of the plate boundary is required to answer...
Authors
Andrea Donnellan, Ramon Arrowsmith, Stephen B. DeLong
Geomorphology, denudation rates, and stream channel profiles reveal patterns of mountain building adjacent to the San Andreas fault in northern California, USA
Relative horizontal motion along strike-slip faults can build mountains when motion is oblique to the trend of the strike-slip boundary. The resulting contraction and uplift pose off-fault seismic hazards, which are often difficult to detect because of the poor vertical resolution of satellite geodesy and difficulty of locating offset datable landforms in active mountain ranges. Sparse...
Authors
Stephen B. DeLong, George E. Hilley, Carol S. Prentice, Christopher J. Crosby, Intan N. Yokelson
CO2 diffusion into pore spaces limits weathering rate of an experimental basalt landscape
Basalt weathering is a key control over the global carbon cycle, though in situ measurements of carbon cycling are lacking. In an experimental, vegetation-free hillslope containing 330 m3 of ground basalt scoria, we measured real-time inorganic carbon dynamics within the porous media and seepage flow. The hillslope carbon flux (0.6–5.1 mg C m–2 h–1) matched weathering rates of natural...
Authors
Joost van Haren, Katerina Dontsova, Greg A. Barron-Gafford, Peter A. Troch, Jon Chorover, Stephen B. DeLong, David D. Breshears, Travis E. Huxman, Jon D. Pelletier, Scott Saleska, Xubin Zeng, Joaquin Ruiz
Science and Products
Exploiting high-resolution topography for advancing the understanding of mass and energy transfer across landscapes: Opportunities, challenges, and needs
One of the grand challenges of Earth Surface Science and Natural Resource Management lies in the prediction of mass and energy transfer for large watersheds and landscapes. High resolution topography (lidar) datasets show potential to significantly advance our understanding of hydrologic and geomorphic processes controlling mass and energy transfer because they represent features at the...
Filter Total Items: 20
Datasets documenting late Pleistocene faulting in the Pondosa fault zone, Pit River Region, Northeastern California
These datasets provide bedrock mapping and geochemistry, low-temperature thermochronology, remotely mapped lineaments, field observations of interpreted faults, and structure from motion models in the Pit River Region of northeastern California. The bedrock mapping datasets contain bedding orientations and field rock descriptions and associated geochemistry and 40Ar/39Ar data for a...
Earthquake geology inputs for the National Seismic Hazard Model (NSHM) 2025 (Puerto Rico and U.S. Virgin Islands), version 1.0
This Data Release contains preliminary versions of three related geologic input databases for the Puerto Rico and U.S. Virgin Islands (PRVI) region (62°–70° W and 16°–21° N) of the United States: 1) A fault sections database (“NSHM2025_FaultSections_PRVI_v1’”), which depicts the geometry of faults capable of hosting independent earthquakes, 2) a fault-zone polygon database ("NSHM2025...
Digital elevation and point cloud data from laser scanning at the Gualala paleoseismic site along the San Andreas Fault
These data are derived from laser scanning surveys of a paleoseismic investigation site along the north coast section of the San Andreas Fault near Gualala, CA. We performed three surveys with a terrestrial laser scanner at different stages of trench excavation in 2021. To generate more complete maps of the bare ground at the site, we also incorporated airborne laser scanner data from...
Earthquake geology inputs for the U.S. National Seismic Hazard Model (NSHM) 2023 (western U.S.) (ver. 3.0, December 2023)
This Data Release contains version 3.0 of two related earthquake geology databases for use in the 2023 U.S. National Seismic Hazard Model. The databases are: 1) A fault sections database (“NSHM23_FSD_v3”), which depicts the geometry of faults capable of hosting independent earthquakes, and 2) an earthquake geology site information database (“NSHM23_EQGeoDB_v3”), which contains fault slip...
High-resolution seismic imaging data acquired in 2021 across the West Winters Fault, Great Valley Fault System at Bigelow Hills, Yolo County, California
In June of 2021, the U.S. Geological Survey conducted a high-resolution seismic survey at Winters, California. Seismic data were acquired using a DTCC SmartSolo 3-component nodal seismograph system ("node"), which continuously recorded at 2000 samples per second. Nodes were deployed 5 meters apart from west-southwest to east-northeast to create an approximately 800-m-long linear profile...
Suspended sediment and bedload data, simple linear regression models, loads, elevation data, and FaSTMECH models for Rice Creek, Minnesota, 2010-2019
A series of simple linear regression models were developed for the U.S. Geological Survey (USGS) streamgage at Rice Creek below Highway 8 in Mounds View, Minnesota (USGS station number 05288580). The simple linear regression models were calibrated using streamflow data to estimate suspended-sediment (total, fines, and sands) and bedload. Data were collected during water years 2010, 2011...
Earthquake geology inputs for the U.S. National Seismic Hazard Model (NSHM) 2023 (western US) (ver. 2.0, February 2022)
This Data Release contains preliminary versions of two related databases: 1) A fault sections database ('NSHM23_FSD_v2'), which depicts the geometry of faults capable of hosting independent earthquakes, and 2) An earthquake geology site information database ('NSHM23_EQGeoDB_v2'), which contains fault slip-rate constraints at points. These databases were prepared in anticipation of...
Inventory of landslides in the northwestern, northeastern, southern, and southeastern parts of Minnesota
This dataset contains an inventory of landslides in many of the most landslide-prone parts of Minnesota. This project was created to improve our understanding of the landslide hazard in Minnesota and to provide a nearly statewide base map of landslide data. The mapping was performed by geologists from the U.S. Geological Survey, the Freshwater Society, and several academic institutions...
Raster and mapping data indicating landscape change from the June 2012 storm in the Duluth, MN region
The GeoTiff raster data were created from subtraction of elevation values collected in 2012 from elevation values collected in 2011. Both data collections were conducted by airborne lidar surveys contracted by the Minnesota Department of Natural Resources. These survey occured before and after a historical rain event that cause widespread landscape change. The shapefiles are polygon...
Reclassified lidar point cloud data from 2016 LARIAC and 2019 NCALM collections covering part of the Woolsey wildfire near Malibu, California
These lidar data are derived from two airborne lidar surveys: a 2016 Los Angeles Region Imagery Acquisition Consortium (LARIAC) survey, and a 2019 National Center for Airborne Laser Mapping (NCALM) survey. These data were reclassified in order to improve the classification of ground points, and to make the classification of both datasets as consistent as possible. The NCALM data had...
Lidar point cloud, GNSS, and raster data from near St. Helena, CA, March 30 and August 1, 2017
Text files: These data are text files of GNSS survey points collected along a trace of the West Napa Fault Zone near Ehler?s Lane north of St. Helena, California. Data were collected to aid in paleoseismic investigation of the suspected fault strand and to characterize local geomorphology. Data were collected on March 31, and August 1, 2017 using a Leica Viva GS15 survey grade GPS. The...
Earthquake geology inputs for the U.S. National Seismic Hazard Model (NSHM) 2023, version 1.0
This Data Release contains preliminary versions of two related databases: 1) A fault sections database ("NSHM2023_FaultSections_v1"), which depicts the geometry of faults capable of hosting independent earthquakes, and 2) An earthquake geology site information database ("NSHM2023_EQGeoDB_v1"), which contains fault slip-rate constraints at points. These databases were prepared in...
Filter Total Items: 30
Evaluating post-wildfire debris-flow rainfall thresholds and volume models at the 2020 Grizzly Creek Fire in Glenwood Canyon, Colorado, USA
As wildfire increases in the western United States, so do postfire debris-flow hazards. The U.S. Geological Survey (USGS) has developed two separate models to estimate (1) rainfall intensity thresholds for postfire debris-flow initiation and (2) debris-flow volumes. However, the information necessary to test the accuracy of these models is seldom available. Here, we studied how well...
Authors
Francis K. Rengers, Samuel Bower, Andrew Knapp, Jason W. Kean, Danielle W. vonLembke, Matthew A. Thomas, Jaime Kostelnik, Katherine R. Barnhart, Matthew Bethel, Joseph E. Gartner, Madeline Hille, Dennis M. Staley, Justin K. Anderson, Elizabeth K. Roberts, Stephen B. DeLong, Belize Lane, Paxton Ridgeway, Brendan Murphy
Sediment monitoring and streamflow modeling before and after a stream restoration in Rice Creek, Minnesota, 2010–2019
The Rice Creek Watershed District (RCWD) cooperated with the U.S. Geological Survey to establish a 10-year suspended sediment and bedload monitoring and streamflow modeling study to evaluate the effects of two restored meander sections on middle Rice Creek in Arden Hills, Minnesota. The RCWD goals of this stream restoration were to reduce water quality impairments, improve aquatic...
Authors
Joel T. Groten, Colin T. Livdahl, Stephen B. DeLong, J. William Lund, Jonathan M. Nelson, Erin N. Coenen, Jeffrey R. Ziegeweid, Matthew J. Kocian
Landslides in Minnesota
Landslides in Minnesota have caused loss of life, damaged infrastructure, and negatively affected Minnesota’s natural resources. Landslides increase the amount of sediment contributed to lakes and rivers, with negative consequences for water quality and aquatic habitats. Recent mapping reveals that landslide susceptible areas within Minnesota primarily occur on steep slopes adjacent to...
Authors
Stephen B. DeLong, Carrie E. Jennings, Karen B. Gran
Streambank erosion and related geomorphic change in Tuolumne Meadows, Yosemite National Park, California
Landscape change in Tuolumne Meadows, Yosemite National Park, California, was characterized using data derived from four lidar surveys: one airborne survey in 2006 and three terrestrial surveys in 2016, 2017, and 2018. These surveys were used to generate a better quantitative understanding of changes associated with fluvial processes along the reach of the Tuolumne River within Tuolumne...
Authors
Stephen B. DeLong, Alexandra J. Pickering, Timothy Kuhn
Rapid strain release on the Bear River fault zone, Utah–Wyoming—The impact of preexisting structure on the rupture behavior of a new normal fault
Earthquake clustering (grouping in space and time) is a widely observed mode of strain release in the upper crust, although this behavior on individual faults is a departure from classic elastic rebound theory. In this study, we consider factors responsible for a cluster of earthquakes on the Bear River fault zone (BRF), a recently activated, 44-km-long normal fault on the eastern margin...
Authors
Suzanne Hecker, David P. Schwartz, Stephen B. DeLong
Distribution of aseismic deformation along the central San Andreas and Calaveras Faults from differencing repeat airborne lidar
Fault creep reduces seismic hazard and serves as a window into plate boundary processes; however, creep rates are typically constrained with sparse measurements. We use differential lidar topography (11–13 year time span) to measure a spatially dense surface deformation field along a 150 km section of the Central San Andreas and Calaveras faults. We use an optimized windowed‐iterative...
Authors
Chelsea P Scott, Stephen B. DeLong, J Ramon Arrosmith
Documentation of Surface Fault Rupture and Ground‐Deformation Features Produced by the 4 and 5 July 2019 Mw 6.4 and Mw 7.1 Ridgecrest Earthquake Sequence
The MwMw 6.4 and MwMw 7.1 Ridgecrest earthquake sequence occurred on 4 and 5 July 2019 within the eastern California shear zone of southern California. Both events produced extensive surface faulting and ground deformation within Indian Wells Valley and Searles Valley. In the weeks following the earthquakes, more than six dozen scientists from government, academia, and the private sector...
Authors
Daniel J. Ponti, James Luke Blair, Rosa Carla M, Kate Thomas, Alexandra Pickering, Sinan Akciz, Stephen J. Angster, Jean-Philipe Avouac, Jeffrey Bachhuber, Steven Bacon, Nicolas C. Barth, S. Bennett, Kelly Blake, Stephan Bork, Benjamin A. Brooks, Thomas Bullard, Paul A. Burgess, Colin Chupik, Timothy E. Dawson, Michael DeFrisco, Jaime E. Delano, Stephen B. DeLong, James D. Dolan, Andrea Donnellan, Christopher DuRoss, Todd Ericksen, Erik Frost, Gareth J. Funning, Ryan D. Gold, Nicholas A Graehl, Carlos Gutierrez, Elizabeth Haddon, Alexandra Elise Hatem, John Helms, Janis Hernandez, Christopher S. Hitchcock, Peter Holland, Kenneth W. Hudnut, Katherine J. Kendrick, Richard D Koehler, Ozgur Kozaci, Tyler C. Ladinsky, Robert Leeper, Christopher Madugo, Maxime Mareschal, James McDonald, Devin McPhillips, Christopher Milliner, Daniel Mongovin, Alexander Morelan, Stephanie Nale, Johanna Nevitt, Matt O'Neal, Brian J. Olsen, Michael Oskin, Salena Padilla, Jason Patton, Belle E. Philibosian, Ian Pierce, Cynthia Pridmore, Nathaniel Roth, David Sandwell, Katherine M. Scharer, Gordon G. Seitz, Drake Singleton, Bridget Smith-Konter, Eleanor Spangler, Brian J. Swanson, Jessica Thompson Jobe, Jerome Treiman, Francesca Valencia, Joshua Vanderwal, Alana Williams, Xiaohua Xu, Judith Zachariasen, Jade Zimmerman, Robert Zinke
Landscape change associated with the upper Scenic Drive landslide, La Honda, California, January 10–June 28, 2017
La Honda, California, is a small town in unincorporated San Mateo County, located on the west edge of the San Francisco Peninsula in the Santa Cruz Mountains, between San Francisco and San Jose. The Scenic Drive area of La Honda has experienced several past episodes of landslide motion, which were documented in 1998, 2005, and 2006. This report documents the movement of the upper Scenic...
Authors
Alexandra J. Pickering, Carol S. Prentice, Stephen B. DeLong
Post-wildfire landscape change and erosional processes from repeat terrestrial lidar in a steep headwater catchment, Chiricahua Mountains, Arizona, USA
Flooding and erosion after wildfires present increasing hazard as climate warms, semi-arid lands become drier, population increases, and the urban interface encroaches farther into wildlands. We quantify post-wildfire erosion in a steep, initially unchannelized, 7.5 ha headwater catchment following the 2011 Horseshoe 2 Fire in the Chiricahua Mountains of southeastern Arizona. Using time...
Authors
Stephen B. DeLong, Ann M. Youberg, Whitney M. DeLong, Brendan P. Murphy
Spatio-temporal mapping of plate boundary faults in California using geodetic imaging
The Pacific–North American plate boundary in California is composed of a 400-km-wide network of faults and zones of distributed deformation. Earthquakes, even large ones, can occur along individual or combinations of faults within the larger plate boundary system. While research often focuses on the primary and secondary faults, holistic study of the plate boundary is required to answer...
Authors
Andrea Donnellan, Ramon Arrowsmith, Stephen B. DeLong
Geomorphology, denudation rates, and stream channel profiles reveal patterns of mountain building adjacent to the San Andreas fault in northern California, USA
Relative horizontal motion along strike-slip faults can build mountains when motion is oblique to the trend of the strike-slip boundary. The resulting contraction and uplift pose off-fault seismic hazards, which are often difficult to detect because of the poor vertical resolution of satellite geodesy and difficulty of locating offset datable landforms in active mountain ranges. Sparse...
Authors
Stephen B. DeLong, George E. Hilley, Carol S. Prentice, Christopher J. Crosby, Intan N. Yokelson
CO2 diffusion into pore spaces limits weathering rate of an experimental basalt landscape
Basalt weathering is a key control over the global carbon cycle, though in situ measurements of carbon cycling are lacking. In an experimental, vegetation-free hillslope containing 330 m3 of ground basalt scoria, we measured real-time inorganic carbon dynamics within the porous media and seepage flow. The hillslope carbon flux (0.6–5.1 mg C m–2 h–1) matched weathering rates of natural...
Authors
Joost van Haren, Katerina Dontsova, Greg A. Barron-Gafford, Peter A. Troch, Jon Chorover, Stephen B. DeLong, David D. Breshears, Travis E. Huxman, Jon D. Pelletier, Scott Saleska, Xubin Zeng, Joaquin Ruiz