Publications

Characterizing short-term temporal variations of fault creep provides insight into the evolution, mechanics, and strength of fault systems. Using spirit leveling and an extensome- ter, we measured surface displacement of a fault southwest of the Needles District, Canyon- lands National Park, Utah, where extension is driven by differential unloading of a subsur- face salt layer due to...

Turbidity currents transport globally significant volumes of sediment and organic carbon into the deep-sea and pose a hazard to critical infrastructure. Despite advances in technology, their powerful nature often damages expensive instruments placed in their path. These challenges mean that turbidity currents have only been measured in a few locations worldwide, in relatively shallow...

The M 7.1 2018 Anchorage earthquake occurred in the bending part of the subducting North Pacific plate near the geometrical barrier formed by the underthrusting Yakutat terrane. We calculate the triggering potential related with stress redistribution from deformation sources including the M 9.2 1964 earthquake coseismic slip, postseismic deformation, slip from regional M > 5 earthquakes...

Megathrust roughness and structural complexity are thought to be controls on earthquake slip at subduction zones because they result in heterogeneity in shear strength and resolved stress. However, because active megathrust faults are difficult to observe, the causes and scales of complexity are largely unknown. Here we measured the in situ properties of the megathrust of the Middle...

Sea-level rise will radically redefine the coastline of the 21st century. For many coastal regions, projections of global sea-level rise by the year 2100 (e.g., 0.5–2 meters) are comparable in magnitude to today’s extreme but short-lived increases in water level due to storms. Thus, the 21st century will see significant changes to coastal flooding regimes (where present-day, extreme-but...

The Rio Grande Rise (RGR) is a large elevation in the Atlantic Ocean and known to host potential mineral resources of ferromanganese crusts (Fe–Mn), but no investigation into their general characteristics have been made in detail. Here, we investigate the chemical and mineralogical composition, growth rates and ages of initiation, and phosphatization of relatively shallow-water (650–825...

Tropical coral reef-lined coasts are exposed to storm wave-driven flooding. In the future, flood events during storms are expected to occur more frequently and to be more severe due to sea-level rise, changes in wind and weather patterns, and the deterioration of coral reefs. Hence, disaster managers and coastal planners are in urgent need of decision-support tools. In the short-term...

A lipid biomarker study was undertaken to determine the microbial composition and variability in authigenic carbonates and associated soft bottom habitats from the Norfolk and the Baltimore Canyon seep fields along the US mid-Atlantic margin. Results from this study capture a distinct molecular signal from methane oxidizing archaea, including archaeol (I), sn-2-hydroxyarchaeol...

Hydrothermal activity results in the formation of hydrothermal mineral deposits, including seafloor massive sulfide deposits, at oceanic spreading ridges, arcs, and back-arcs. As hydrothermal systems age, the mineral deposits eventually become severed from the heat source and fluid-flow pathways responsible for their formation and become extinct. The timescales and processes by which...

Interactions among microorganisms and their mineralogical substrates govern the structure, function, and emergent properties of microbial communities. These interactions are predicated on spatial relationships, which dictate metabolite exchange and access to key substrates. To quantitatively assess links between spatial relationships and metabolic activity, this study presents a novel...

Organic geochemistry is commonly used in environmental studies. In tsunami research, however, its applications are in their infancy and it is still rarely used. We present results for two types of organic geochemical markers, biomarkers and anthropogenic markers, present in deposits left by 2011 Tohoku-oki tsunami on the Sendai Plain, Japan. As the tsunami inundated the coastal lowland...

Coseismic stress changes have been the primary physical principle used to explain aftershocks and triggered earthquakes. However, this method does not adequately forecast earthquake rates and diverse rupture populations when subjected to formal testing. We show that earthquake forecasts can be impaired by assumptions made in physics-based models, such as the existence of hypothetical...