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Hillslopes in humid-tropical climates aren’t always wet: Implications for hydrologic response and landslide initiation in Puerto Rico, USA

The devastating impacts of the widespread flooding and landsliding in Puerto Rico following the September 2017 landfall of Hurricane Maria highlight the increasingly extreme atmospheric disturbances and enhanced hazard potential in mountainous humid‐tropical climate zones. Long‐standing conceptual models for hydrologically driven hazards in Puerto Rico posit that hillslope soils remain wet through

Authors
Matthew A. Thomas, Benjamin B. Mirus, Joel B. Smith

Increasing threat of coastal groundwater hazards from sea-level rise in California

Projected sea-level rise will raise coastal water tables, resulting in groundwater hazards that threaten shallow infrastructure and coastal ecosystem resilience. Here we model a range of sea-level rise scenarios to assess the responses of water tables across the diverse topography and climates of the California coast. With 1 m of sea-level rise, areas flooded from below are predicted to expand ~50
Authors
K.M. Befus, Patrick L. Barnard, Daniel J. Hoover, Juliette Finzi Hart, Clifford I. Voss

Constraining central Himalayan (Nepal) fault geometry through integrated thermochronology and thermokinematic modeling

Constraining the subsurface structural geometry of the central Himalaya continues to prove difficult, even after the 2015 Gorkha earthquake and the resulting insights into the trajectory of the Main Himalayan thrust (MHT). To this end, we apply a thermokinematic model to evaluate four possible balanced cross section geometries based on three estimates of the MHT in central Nepal. We compare the ef
Authors
Surydoy Ghoshal, Nadine McQuarrie, Delores Robinson, D.P. Adhikari, Leah E. Morgan, Todd A. Ehlers

Now trending … Earthquake information

The U.S. Geological Survey Earthquake Hazards Program has overall successfully fulfilled its mission of providing timely earthquake information via web applications and other methods. Imagine a single month of earthquake data delivery, serving 3.6 billion total data requests, including 29 million pageviews by 7.1 million users, 606 million automated data feeds, and 45 million catalog downloads. Ye
Authors
William S. Leith, Jeremy Fee, Eric M. Martinez, Lynda A. Lastowka

Financial risk innovation: Development of earthquake parametric triggers for contingent credit instruments

The Inter-American Development Bank (IDB) has developed financial risk management strategies for natural disasters focusing primarily on the emergency phase of the catastrophes where financial support is more cost-efficient and certainly most needed. The main IDB financial instrument to provide liquidity in the aftermath of catastrophic events is the Contingent Credit Facility (CCF). The CCF is a
Authors
Guillermo Collich, Rafael Rosillo, Juan Martinez, David J. Wald, Juan José Durante

A stress-similarity triggering model for aftershocks of the MW6.4 and MW7.1 Ridgecrest earthquakes

The July 2019 Mw 6.4 and 7.1 Ridgecrest earthquakes triggered numerous aftershocks, including clusters of off‐fault aftershocks in an extensional stepover of the Garlock fault, near the town of Olancha, and near Panamint Valley. The locations of the off‐fault aftershocks are consistent with the stress‐similarity model of triggering, which hypothesizes that aftershocks preferentially occur in areas
Authors
Jeanne L. Hardebeck

Are the stress drops of small earthquakes good predictors of the stress drops of moderate-to-large earthquakes?

The stress drops of small earthquakes often exhibit spatial patterns of variability. If moderate and large earthquakes follow the same spatial patterns, the stress drops of possible future damaging earthquakes could be better predicted by considering the stress drops of nearby small events. Better stress drop predictability could reduce ground-motion uncertainty in Probabilistic Seismic Hazard As
Authors
Jeanne L. Hardebeck

Landslides after wildfire: Initiation, magnitude, and mobility

In the semiarid Southwestern USA, wildfires are commonly followed by runoff-generated debris flows because wildfires remove vegetation and ground cover, which reduces soil infiltration capacity and increases soil erodibility. At a study site in Southern California, we initially observed runoff-generated debris flows in the first year following fire. However, at the same site three years after the
Authors
Francis K. Rengers, Luke McGuire, Nina S. Oakley, Jason W. Kean, Dennis M. Staley, Hui Tang

Internal tides can provide thermal refugia that will buffer some coral reefs from future global warming

Observations show ocean temperatures are rising due to climate change, resulting in a fivefold increase in the incidence of regional-scale coral bleaching events since the 1980s; analyses based on global climate models forecast bleaching will become an annual event for most of the world’s coral reefs within 30–50 yr. Internal waves at tidal frequencies can regularly flush reefs with cooler waters,
Authors
Curt D. Storlazzi, Olivia Cheriton, Ruben Van Hooidonk, Zhongxiang Zhao, Russell E. Brainard

Ancient Martian aeolian sand dune deposits recorded in the stratigraphy of Valles Marineris and implications for past climates

Aeolian sediment transport, deposition, and erosion have been ongoing throughout Mars's history. This record of widespread aeolian processes is preserved in landforms and geologic units that retain important clues about past environmental conditions including wind patterns. In this study we describe landforms within Melas Chasma, Valles Marineris, that occur in distinct groups with linear to cresc
Authors
Matthew Chojnacki, Lori K. Fenton, Aaron R Weintraub, Lauren A. Edgar, Mohini Jeetendra Jodhpurkar, Christopher S. Edwards

Focused fluid flow along the Nootka Fault Zone and continental slope, Explorer-Juan de Fuca plate boundary

Geophysical and geochemical data indicate there is abundant fluid expulsion in the Nootka fault zone (NFZ) between the Juan de Fuca and Explorer plates and the Nootka continental slope. Here we combine observations from > 20 years of investigations to demonstrate the nature of fluid-flow along the NFZ, which is the seismically most active region off Vancouver Island. Seismicity reaching down to th
Authors
M. Riedel, K .M. M. Rohr, G. D. Spence, D. Kelley, J. Delaney, L. Lapham, John Pohlman, R.D. Hyndman, E.C. Willoughby

Seismicity induced by massive wastewater injection near Puerto Gaitán, Colombia

Seven years after the beginning of a massive wastewater injection project in eastern Colombia, local earthquake activity increased significantly. The field operator and the Colombian Geological Survey immediately reinforced the monitoring of the area. Our analysis of the temporal evolution of the seismic and injection data together with our knowledge of the geological parameters of the region indi
Authors
I Molina, J.S. Velasquez, Justin Rubinstein, A García-Aristizabal, V Dionicio