Publications
Pore pressure threshold and fault slip potential for induced earthquakes in the Dallas-Fort Worth area of north central Texas
Earthquakes were induced in the Fort Worth Basin from 2008 through 2020 by increase in pore pressure from injection of oilfield wastewater (SWD). In this region and elsewhere, a missing link in understanding the mechanics of causation has been a lack of comprehensive models of pore pressure evolution (ΔPp) from SWD. We integrate detailed earthquake catalogs, ΔPp, and probabilistic fault slip poten
Influence of invasive submerged aquatic vegetation (E. densa) on currents and sediment transport in a freshwater tidal system
We present a field study combining measurements of vegetation density, vegetative drag, and reduction of suspended-sediment concentration (SSC) within patches of the invasive submerged aquatic plant Egeria densa. Our study was motivated by concern that sediment trapping by E. densa, which has proliferated in the Sacramento–San Joaquin Delta, is impacting marsh accretion and reducing turbidity. In
Impacts of sediment removal from and placement in coastal barrier island systems
Executive SummaryOn June 24, 2019, Congressman Raul Grijalva of Arizona, Chair of the House Committee on Natural Resources, sent a letter to the directors of the U.S. Fish and Wildlife Service and the U.S. Geological Survey to request their assistance in answering questions regarding coastal sediment resource management within the Coastal Barrier Resources System as defined by the Coastal Barrier
Dating fault damage along the eastern Denali fault zone with hematite (U-Th)/He thermochronometry
Unraveling complex slip histories in fault damage zones to understand relations among deformation, hydrothermal alteration, and surface uplift remains a challenge. The dextral eastern Denali fault zone (EDFZ; southwest Yukon, Canada) bounds the Kluane Ranges and hosts a variety of fault-related rocks, including hematite fault surfaces, which have been exhumed through the brittle regime over a prot
Quantifying thresholds of barrier geomorphic change in a cross-shore sediment-partitioning model
Barrier coasts, including barrier islands, beach-ridge plains, and associated landforms, can assume a broad spectrum of morphologies over multi-decadal scales that reflect conditions of sediment availability, accommodation, and relative sea-level rise. However, the quantitative thresholds of these controls on barrier-system behavior remain largely unexplored, even as modern sea-level rise and anth
Seasonal, spring-neap, and tidal variation in cohesive sediment transport parameters in estuarine shallows
Numerical models for predicting sediment concentrations and transport rely on parameters such as settling velocity and bed erodibility that describe sediment characteristics, yet these parameters are rarely probed directly. We investigated temporal and spatial variation in sediment parameters in the shallows of San Pablo Bay, CA. Flow, turbulence, and suspended sediment data were measured at sites
Thermotectonic history of the Kluane Ranges and evolution of the eastern Denali Fault Zone in southwestern Yukon, Canada
Exhumation and landscape evolution along strike‐slip fault systems reflect tectonic processes that accommodate and partition deformation in orogenic settings. We present 17 new apatite (U‐Th)/He (He), zircon He, apatite fission‐track (FT), and zircon FT dates from the eastern Denali fault zone (EDFZ) that bounds the Kluane Ranges in Yukon, Canada. The dates elucidate patterns of deformation along
Measuring settling velocity in a strongly tidal estuary
Predicting sediment transport in estuarine systems requires understanding sediment settling velocity, its range of fluctuations, and the shortcomings of the tools to measure it. Previous studies have used Laser In-Situ Scattering and Transmissometry (LISST) instruments to measure particle size and Acoustic Doppler Velocimeters (ADV) to return estimates of settling velocity. We deployed both instru