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
2017 seismic imaging of the West Napa Fault Zone, St. Helena, California
Classified point cloud data from the 2005 B4 Lidar Project, southern California
Terrestrial laser scanner data from the 2011 Horseshoe Two fire, Chiricahua Mountains, southeastern Arizona
Terrestrial laser scanner data from Hetch Hetchy area, Yosemite National Park, California, USA
3D point cloud data from laser scanning along the 2014 South Napa Earthquake surface rupture (2016)
Imaging of earthquake faults using small UAVs as a pathfinder for air and space observations
Tearing the terroir: Details and implications of surface rupture and deformation from the 24 August 2014 M6.0 South Napa earthquake, California
Detailed mapping and rupture implications of the 1 km releasing bend in the Rodgers Creek Fault at Santa Rosa, northern California
Afterslip behavior following the M6.0, 2014 South Napa earthquake with implications for afterslip forecasting on other seismogenic faults
Rates and patterns of surface deformation from laser scanning following the South Napa earthquake, California
Trench logs, terrestrial lidar system imagery, and radiocarbon data from the kilometer-62 site on the Greenville Fault, southeastern Alameda County, California, 2014
The Landscape Evolution Observatory: a large-scale controllable infrastructure to study coupled Earth-surface processes
Analyzing high resolution topography for advancing the understanding of mass and energy transfer through landscapes: A review
Arroyo channel head evolution in a flash-flood-dominated discontinuous ephemeral stream system
Key recovery factors for the August 24, 2014, South Napa Earthquake
Hillslope-scale experiment demonstrates role of convergence during two-step saturation
Multitemporal ALSM change detection, sediment delivery, and process mapping at an active earthflow
Science and Products
- Science
- Data
Filter Total Items: 17
2017 seismic imaging of the West Napa Fault Zone, St. Helena, California
In April 2017, the U.S. Geological Survey acquired high resolution P- and S-wave seismic data across the suspected trace of the West Napa Fault zone in St. Helena, California. We acquired seismic reflection, refraction, and guided-wave data along a 215-m-long profile across the expected trend of the West Napa Fault zone. To acquire the reflection and refraction data, we co-located shots and geophoClassified point cloud data from the 2005 B4 Lidar Project, southern California
This data set is derived from the original 2005 data collected over the southern San Andreas and San Jacinto fault zones in southern California, USA. These data have provided a fundamental resource for study of active faulting in southern California since they were released in 2005. However, these data were not classified in a manner that allowed for easy differentiation between bare ground surfacTerrestrial laser scanner data from the 2011 Horseshoe Two fire, Chiricahua Mountains, southeastern Arizona
Point cloud data collected on a steep, severely burned hillslope below Barfoot Peak near Rustler Park in the Chiricahua Mountains, AZ. The data were collected June 21, July 18, August 1, August 23, 2011 and March 14, 2012. The data were collected with a Leica Scanstation C10 High Definition Scanner. The data are delivered as georeferenced (WGS UTM zone 12N ellipsoid) and classified point clouds. TTerrestrial laser scanner data from Hetch Hetchy area, Yosemite National Park, California, USA
These data are 3D point cloud data collected by laser scanner in the Hetch Hetchy area of Yosemite National Park, USA. The data were collected to assess landscape change and vegetation response following the 2013 Rim wildfire. Filename convention: "hh_datatype_dd_ddmmyyyy_laserreturns_siteidentification". "datatype" is either "alsm" or "tls" The former was collected by the National Center for Airb3D point cloud data from laser scanning along the 2014 South Napa Earthquake surface rupture (2016)
Point cloud data in .laz format collected using a 3D laser scanner in Napa California in 2014 and 2015. Also included are aligned airborne laser scanner data from 2003 and 2014. - Multimedia
- Publications
Filter Total Items: 29
Imaging of earthquake faults using small UAVs as a pathfinder for air and space observations
Large earthquakes cause billions of dollars in damage and extensive loss of life and property. Geodetic and topographic imaging provide measurements of transient and long-term crustal deformation needed to monitor fault zones and understand earthquakes. Earthquake-induced strain and rupture characteristics are expressed in topographic features imprinted on the landscapes of fault zones. Small UAVsAuthorsAndrea Donnellan, Joseph Green, Adnan Ansar, Joseph Aletky, Margaret Glasscoe, Yehuda Ben-Zion, J. Ramón Arrowsmith, Stephen B. DeLongTearing the terroir: Details and implications of surface rupture and deformation from the 24 August 2014 M6.0 South Napa earthquake, California
The Mw 6.0 South Napa earthquake of 24 August 2014 caused slip on several active fault strands within the West Napa Fault Zone (WNFZ). Field mapping identified 12.5 km of surface rupture. These field observations, near-field geodesy and space geodesy, together provide evidence for more than ~30 km of surface deformation with a relatively complex distribution across a number of subparallel lineamenAuthorsStephen B. DeLong, Andrea Donnellan, Daniel J. Ponti, Ron S. Rubin, James J. Lienkaemper, Carol S. Prentice, Timothy E. Dawson, Gordon G. Seitz, David P. Schwartz, Kenneth W. Hudnut, Carla M. Rosa, Alexandra J. Pickering, Jay W. ParkerDetailed mapping and rupture implications of the 1 km releasing bend in the Rodgers Creek Fault at Santa Rosa, northern California
Airborne light detection and ranging (lidar) topography reveals for the first time the trace of the Rodgers Creek fault (RCF) through the center of Santa Rosa, the largest city in the northern San Francisco Bay area. Vertical deformation of the Santa Rosa Creek floodplain expresses a composite pull‐apart basin beneath the urban cover that is part of a broader 1‐km‐wide right‐releasing bend in theAuthorsSuzanne Hecker, Victoria E. Langenheim, Robert Williams, Christopher S. Hitchcock, Stephen B. DeLongAfterslip behavior following the M6.0, 2014 South Napa earthquake with implications for afterslip forecasting on other seismogenic faults
The M6.0, 24 Aug. 2014 South Napa, California, earthquake exhibited unusually large slip for a California strike-slip event of its size with a maximum coseismic surface slip of 40-50 cm in the north section of the 15 km-long rupture. Although only minor (AuthorsJames J. Lienkaemper, Stephen B. DeLong, Carolyn J Domrose, Carla M. RosaRates and patterns of surface deformation from laser scanning following the South Napa earthquake, California
The A.D. 2014 M6.0 South Napa earthquake, despite its moderate magnitude, caused significant damage to the Napa Valley in northern California (USA). Surface rupture occurred along several mapped and unmapped faults. Field observations following the earthquake indicated that the magnitude of postseismic surface slip was likely to approach or exceed the maximum coseismic surface slip and as such preAuthorsStephen B. DeLong, James J. Lienkaemper, Alexandra J. Pickering, Nikita N. AvdievitchTrench logs, terrestrial lidar system imagery, and radiocarbon data from the kilometer-62 site on the Greenville Fault, southeastern Alameda County, California, 2014
In 2014, we investigated an abrupt 8.5-meter (m), right-laterally deflected stream channel located near the Greenville Fault in southeastern Alameda County, California (-121.56224° E, 37.53430° N) that we discovered using 0.5-m resolution, 2011 aerial lidar imagery flown along the active fault trace. Prior to trenching we surveyed the site using a terrestrial lidar system (TLS) to document the exaAuthorsJames J. Lienkaemper, Stephen B. DeLong, Nikita N. Avdievitch, Alexandra J. Pickering, Thomas P. GuildersonThe Landscape Evolution Observatory: a large-scale controllable infrastructure to study coupled Earth-surface processes
Zero-order drainage basins, and their constituent hillslopes, are the fundamental geomorphic unit comprising much of Earth's uplands. The convergent topography of these landscapes generates spatially variable substrate and moisture content, facilitating biological diversity and influencing how the landscape filters precipitation and sequesters atmospheric carbon dioxide. In light of these significAuthorsLuke A. Pangle, Stephen B. DeLong, Nate Abramson, John Adams, Greg A. Barron-Gafford, David D. Breshears, Paul D. Brooks, Jon Chorover, William E. Dietrich, Katerina Dontsova, Matej Durcik, Javier Espeleta, T.P.A. Ferré, Regis Ferriere, Whitney Henderson, Edward A. Hunt, Travis E. Huxman, David Millar, Brendan Murphy, Guo-Yue Niu, Mitch Pavao-Zuckerman, Jon D. Pelletier, Craig Rasmussen, Joaquin Ruiz, Scott Saleska, Marcel Schaap, Michael Sibayan, Peter A. Troch, Markus Tuller, Joost van Haren, Xubin ZengAnalyzing high resolution topography for advancing the understanding of mass and energy transfer through landscapes: A review
The study of mass and energy transfer across landscapes has recently evolved to comprehensive considerations acknowledging the role of biota and humans as geomorphic agents, as well as the importance of small-scale landscape features. A contributing and supporting factor to this evolution is the emergence over the last two decades of technologies able to acquire high resolution topography (HRT) (mAuthorsPaola Passaiacquaa, Patrick Belmont, Dennis M. Staley, Jeffery Simley, J. Ramon Arrowsmith, Collin A. Bode, Christopher Crosby, Stephen DeLong, Nancy Glenn, Sara Kelly, Dimitri Lague, Harish Sangireddy, Keelin Schaffrath, David Tarboton, Thad Wasklewicz, Joseph WheatonArroyo channel head evolution in a flash-flood-dominated discontinuous ephemeral stream system
We study whether arroyo channel head retreat in dryland discontinuous ephemeral streams is driven by surface runoff, seepage erosion, mass wasting, or some combination of these hydrogeomorphic processes. We monitored precipitation, overland flow, soil moisture, and headcut migration over several seasonal cycles at two adjacent rangeland channel heads in southern Arizona. Erosion occurred by headwaAuthorsStephen B. DeLong, Joel P. L. Johnson, Kelin X. WhippleKey recovery factors for the August 24, 2014, South Napa Earthquake
Through discussions between the Federal Emergency Management Agency (FEMA) and the U.S. Geological Survey (USGS) following the South Napa earthquake, it was determined that several key decision points would be faced by FEMA for which additional information should be sought and provided by USGS and its partners. This report addresses the four tasks that were agreed to. These tasks are (1) assessmenAuthorsKenneth W. Hudnut, Thomas M. Brocher, Carol S. Prentice, John Boatwright, Benjamin A. Brooks, Brad T. Aagaard, J. Luke Blair, Jon Peter B. Fletcher, Jemile Erdem, Charles W. Wicks, Jessica R. Murray, Fred F. Pollitz, John O. Langbein, Jerry L. Svarc, David P. Schwartz, Daniel J. Ponti, Suzanne Hecker, Stephen B. DeLong, Carla M. Rosa, Brenda Jones, Rynn M. Lamb, Anne M. Rosinski, Timothy P. McCrink, Timothy E. Dawson, Gordon G. Seitz, Craig Glennie, Darren Hauser, Todd Ericksen, Dan Mardock, Don F. Hoirup, Jonathan D. Bray, Ron S. RubinHillslope-scale experiment demonstrates role of convergence during two-step saturation
Subsurface flow and storage dynamics at hillslope scale are difficult to ascertain, often in part due to a lack of sufficient high-resolution measurements and an incomplete understanding of boundary conditions, soil properties, and other environmental aspects. A continuous and extreme rainfall experiment on an artificial hillslope at Biosphere 2's Landscape Evolution Observatory (LEO) resulted inAuthorsA. I. Gevaert, A. J. Teuling, R. Uijlenhoet, Stephen B. DeLong, T. E. Huxman, L. A. Pangle, David D. Breshears, J. Chorover, John D. Pelletier, S. R. Saleska, X. Zeng, Peter A. TrochMultitemporal ALSM change detection, sediment delivery, and process mapping at an active earthflow
Remote mapping and measurement of surface processes at high spatial resolution is among the frontiers in Earth surface process research. Remote measurements that allow meter-scale mapping of landforms and quantification of landscape change can revolutionize the study of landscape evolution on human timescales. At Mill Gulch in northern California, USA, an active earthflow was surveyed in 2003 andAuthorsStephen B. DeLong, Carol S. Prentice, George E. Hilley, Yael Ebert