Harrison Gray, Ph.D
Earth's surface is shaped by the transfer of sediment across time and space. As we live on the Earth's surface, understanding this transport of sediment is key to the well-being of our species. I work on solving problems asscociated with landscapes and sediment transport using the tools of computer landscape evolution modeling and the trapped-charge phenomena known as luminescence.
Education and Certifications
Ph.D Geomorphology, University of Colorado - Boulder, 2018
M.S. Geology, Univeristy of Cincinnati, 2013
B.S. Earth Sciences, University of California - Santa Cruz, 2010
Honors and Awards
Presidential Early Career Award for Scientists and Engineers (PECASE), 2025
Science and Products
Filter Total Items: 14
Luminescence, weather, and grain-size data from eastern Chuckwalla Valley, Riverside County, California Luminescence, weather, and grain-size data from eastern Chuckwalla Valley, Riverside County, California
This data release contains luminescence, weather, and sediment grain-size data from eastern Chuckwalla Valley, Riverside County, California. This study investigates sedimentary and geomorphic processes in eastern Chuckwalla Valley, Riverside County, California, a region of arid, basin-and-range terrain where extensive solar-energy development is planned. The objectives were to (1)...
Data release for application of a luminescence-based sediment transport model Data release for application of a luminescence-based sediment transport model
This data release contains luminescence data from the manuscript "Application of a luminescence-based sediment transport model" by Gray et al. It contains data from the luminescence measurements and experiments in the paper.
Filter Total Items: 28
Portable optically stimulated luminescence age map of a paleoseismic exposure Portable optically stimulated luminescence age map of a paleoseismic exposure
The quality and quantity of geochronologic data used to constrain the history of major earthquakes in a region exerts a first-order control on the accuracy of seismic hazard assessments that affect millions of people. However, evaluations of geochronological data are limited by uncertainties related to inherently complex depositional processes that may vary spatially and temporally. To...
Authors
Christopher DuRoss, Ryan D. Gold, Harrison J. Gray, Sylvia R. Nicovich
A maximum rupture model for the central and southern Cascadia subduction zone—reassessing ages for coastal evidence of megathrust earthquakes and tsunamis A maximum rupture model for the central and southern Cascadia subduction zone—reassessing ages for coastal evidence of megathrust earthquakes and tsunamis
A new history of great earthquakes (and their tsunamis) for the central and southern Cascadia subduction zone shows more frequent (17 in the past 6700 yr) megathrust ruptures than previous coastal chronologies. The history is based on along-strike correlations of Bayesian age models derived from evaluation of 554 radiocarbon ages that date earthquake evidence at 14 coastal sites. We...
Authors
Alan Nelson, Christopher DuRoss, Robert C. Witter, Harvey M. Kelsey, Simon E. Engelhart, Shannon A. Mahan, Harrison J. Gray, Andrea D. Hawkes, Benjamin P. Horton, Jason S. Padgett
Landscape evolution in eastern Chuckwalla Valley, Riverside County, California Landscape evolution in eastern Chuckwalla Valley, Riverside County, California
This study investigates sedimentary and geomorphic processes in eastern Chuckwalla Valley, Riverside County, California, a region of arid, basin-and-range terrain where extensive solar-energy development is planned. The objectives of this study were to (1) measure local weather parameters and use them to model aeolian sediment-transport potential; (2) identify surface sedimentary...
Authors
Amy E. East, Harrison J. Gray, Margaret Hiza Redsteer, Matthew Ballmer
Depth-dependent soil mixing persists across climate zones Depth-dependent soil mixing persists across climate zones
Soil mixing over long (>102 y) timescales enhances nutrient fluxes that support soil ecology, contributes to dispersion of sediment and contaminated material, and modulates fluxes of carbon through Earth’s largest terrestrial carbon reservoir. Despite its foundational importance, we lack robust understanding of the rates and patterns of soil mixing, largely due to a lack of long...
Authors
Harrison J. Gray, Amanda Keen-Zebert, David Furbish, Gregory E. Tucker, Shannon A. Mahan
Luminescence as a sediment tracer and provenance tool Luminescence as a sediment tracer and provenance tool
Luminescence holds unique potential as a sediment tracer and provenance method. The tracer application of luminescence has key advantages including ease of measurement, relatively low cost, and applicability to geologically ubiquitous quartz and feldspar sand and silt. These advantages can help answer fundamental questions about geomorphology, sediment transport, sediment production, and...
Authors
Harrison J. Gray, Mayank Jain, Andre Sawakuchi, Shannon A. Mahan, Gregory E. Tucker
Paleoseismic results from the Alpine site, Wasatch fault zone: Timing and displacement data for six holocene earthquakes at the Salt Lake City–Provo segment boundary Paleoseismic results from the Alpine site, Wasatch fault zone: Timing and displacement data for six holocene earthquakes at the Salt Lake City–Provo segment boundary
To improve the characterization of Holocene earthquakes on the Wasatch fault zone (WFZ), we conducted light detection and ranging (lidar)‐based neotectonic mapping and excavated a paleoseismic trench across an 8‐m‐high fault scarp near Alpine, Utah, located ∼6.2–0.4 ka∼6.2–0.4 ka. Interseismic recurrence ranges from 0.2 to 1.8 ky (mean 1.2 ky). We estimate 6.5±0.7 m6.5±0.7 m of...
Authors
Scott E.K. Bennett, Christopher DuRoss, Ryan D. Gold, Richard W. Briggs, Stephen Personius, Nadine G. Reitman, Joshua Devore, Adam Hiscock, Shannon A. Mahan, Harrison J. Gray, Sydney Gunnarson, William J. Stephenson, Elizabeth Pettinger, Jackson K. Odum
Science and Products
Filter Total Items: 14
Luminescence, weather, and grain-size data from eastern Chuckwalla Valley, Riverside County, California Luminescence, weather, and grain-size data from eastern Chuckwalla Valley, Riverside County, California
This data release contains luminescence, weather, and sediment grain-size data from eastern Chuckwalla Valley, Riverside County, California. This study investigates sedimentary and geomorphic processes in eastern Chuckwalla Valley, Riverside County, California, a region of arid, basin-and-range terrain where extensive solar-energy development is planned. The objectives were to (1)...
Data release for application of a luminescence-based sediment transport model Data release for application of a luminescence-based sediment transport model
This data release contains luminescence data from the manuscript "Application of a luminescence-based sediment transport model" by Gray et al. It contains data from the luminescence measurements and experiments in the paper.
Filter Total Items: 28
Portable optically stimulated luminescence age map of a paleoseismic exposure Portable optically stimulated luminescence age map of a paleoseismic exposure
The quality and quantity of geochronologic data used to constrain the history of major earthquakes in a region exerts a first-order control on the accuracy of seismic hazard assessments that affect millions of people. However, evaluations of geochronological data are limited by uncertainties related to inherently complex depositional processes that may vary spatially and temporally. To...
Authors
Christopher DuRoss, Ryan D. Gold, Harrison J. Gray, Sylvia R. Nicovich
A maximum rupture model for the central and southern Cascadia subduction zone—reassessing ages for coastal evidence of megathrust earthquakes and tsunamis A maximum rupture model for the central and southern Cascadia subduction zone—reassessing ages for coastal evidence of megathrust earthquakes and tsunamis
A new history of great earthquakes (and their tsunamis) for the central and southern Cascadia subduction zone shows more frequent (17 in the past 6700 yr) megathrust ruptures than previous coastal chronologies. The history is based on along-strike correlations of Bayesian age models derived from evaluation of 554 radiocarbon ages that date earthquake evidence at 14 coastal sites. We...
Authors
Alan Nelson, Christopher DuRoss, Robert C. Witter, Harvey M. Kelsey, Simon E. Engelhart, Shannon A. Mahan, Harrison J. Gray, Andrea D. Hawkes, Benjamin P. Horton, Jason S. Padgett
Landscape evolution in eastern Chuckwalla Valley, Riverside County, California Landscape evolution in eastern Chuckwalla Valley, Riverside County, California
This study investigates sedimentary and geomorphic processes in eastern Chuckwalla Valley, Riverside County, California, a region of arid, basin-and-range terrain where extensive solar-energy development is planned. The objectives of this study were to (1) measure local weather parameters and use them to model aeolian sediment-transport potential; (2) identify surface sedimentary...
Authors
Amy E. East, Harrison J. Gray, Margaret Hiza Redsteer, Matthew Ballmer
Depth-dependent soil mixing persists across climate zones Depth-dependent soil mixing persists across climate zones
Soil mixing over long (>102 y) timescales enhances nutrient fluxes that support soil ecology, contributes to dispersion of sediment and contaminated material, and modulates fluxes of carbon through Earth’s largest terrestrial carbon reservoir. Despite its foundational importance, we lack robust understanding of the rates and patterns of soil mixing, largely due to a lack of long...
Authors
Harrison J. Gray, Amanda Keen-Zebert, David Furbish, Gregory E. Tucker, Shannon A. Mahan
Luminescence as a sediment tracer and provenance tool Luminescence as a sediment tracer and provenance tool
Luminescence holds unique potential as a sediment tracer and provenance method. The tracer application of luminescence has key advantages including ease of measurement, relatively low cost, and applicability to geologically ubiquitous quartz and feldspar sand and silt. These advantages can help answer fundamental questions about geomorphology, sediment transport, sediment production, and...
Authors
Harrison J. Gray, Mayank Jain, Andre Sawakuchi, Shannon A. Mahan, Gregory E. Tucker
Paleoseismic results from the Alpine site, Wasatch fault zone: Timing and displacement data for six holocene earthquakes at the Salt Lake City–Provo segment boundary Paleoseismic results from the Alpine site, Wasatch fault zone: Timing and displacement data for six holocene earthquakes at the Salt Lake City–Provo segment boundary
To improve the characterization of Holocene earthquakes on the Wasatch fault zone (WFZ), we conducted light detection and ranging (lidar)‐based neotectonic mapping and excavated a paleoseismic trench across an 8‐m‐high fault scarp near Alpine, Utah, located ∼6.2–0.4 ka∼6.2–0.4 ka. Interseismic recurrence ranges from 0.2 to 1.8 ky (mean 1.2 ky). We estimate 6.5±0.7 m6.5±0.7 m of...
Authors
Scott E.K. Bennett, Christopher DuRoss, Ryan D. Gold, Richard W. Briggs, Stephen Personius, Nadine G. Reitman, Joshua Devore, Adam Hiscock, Shannon A. Mahan, Harrison J. Gray, Sydney Gunnarson, William J. Stephenson, Elizabeth Pettinger, Jackson K. Odum