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Southwest Region

The Southwest Region covers Arizona, California, Nevada, and a portion of southern Oregon. Our scientists do a broad array of research and technical assistance throughout the U.S. and across the globe. The Regional Office, headquartered in Sacramento, provides Center oversight & support, facilitates internal & external collaborations, and works to further USGS strategic science direction.

News

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What We Do: Coastal and Marine Science at USGS Santa Cruz

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Media Alert: Low-Level Helicopter Flights to Image Geology in Western Nevada

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USGS-Led Study Reassesses Earthquake Hazard Potential for Central California’s Hosgri Fault

Publications

Analyzing spatial distributions and alignments of pitted cone features in Utopia Planitia on Mars

Martian geomorphology and surface features provide links to understanding past geologic processes such as fluid movement, local and regional tectonics, and feature formation mechanisms. Pitted cones are common features in the northern plains basins of Mars. They have been proposed to have formed from upwelling volatile-rich fluids, such as magma or water-sediment slurries. In this study, we map th
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Mackenzie M. Mills, Alfred S. McEwen, Amanda N. Hughes, Ji-Eun Kim, Chris Okubo

Soil surface treatments and precipitation timing determine seedling development across southwestern US restoration sites

Restoration in dryland ecosystems often has poor success due to low and variable water availability, degraded soil conditions, and slow plant community recovery rates. Restoration treatments can mitigate these constraints but, because treatments and subsequent monitoring are typically limited in space and time, our understanding of their applicability across broader environmental gradients remains
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Hannah Lucia Farrell, Seth M. Munson, Bradley J. Butterfield, Michael C. Duniway, Aksasha M Faist, Elise S Gornish, Caroline Havrilla, Loralee Larios, Sasha C. Reed, Helen I Rowe, Katherine M. Laushman, Molly L. McCormick

Addressing stakeholder science needs for integrated drought science in the Colorado River Basin

Stakeholders need scientific data, analysis, and predictions of how drought the will impact the Colorado River Basin in a format that is continuously updated, intuitive, and easily accessible. The Colorado River Basin Actionable and Strategic Integrated Science and Technology Pilot Project was formed to demonstrate the effectiveness of addressing complex problems through stakeholder involvement an
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Anne C. Tillery, Sally House, Rebecca J. Frus, Sharon L. Qi, Daniel Jones, William J. Andrews

Science

M6.4 March 10, 1933 Long Beach, California Earthquake

The magnitude 6.4 Long Beach, California earthquake, which struck near 5pm local time on March 10, 1933, was a landmark event. It was the largest known earthquake in the Los Angeles region at the time, since the advent of written record-keeping. It occurred at a pivotal point historically, during an active debate about seismic hazard in the area.
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M6.4 March 10, 1933 Long Beach, California Earthquake

The magnitude 6.4 Long Beach, California earthquake, which struck near 5pm local time on March 10, 1933, was a landmark event. It was the largest known earthquake in the Los Angeles region at the time, since the advent of written record-keeping. It occurred at a pivotal point historically, during an active debate about seismic hazard in the area.
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Planetary Defense

At the USGS Astrogeology Science Center we conduct research on Planetary Defense. Planetary Defense involves predicting potential impactors (asteroids, comets), and studying how to deflect or divert them, as well as the potential effects of an impact. Effects include short-term effects such as blast damage, but also long-term effects such as climate and social impacts.
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Planetary Defense

At the USGS Astrogeology Science Center we conduct research on Planetary Defense. Planetary Defense involves predicting potential impactors (asteroids, comets), and studying how to deflect or divert them, as well as the potential effects of an impact. Effects include short-term effects such as blast damage, but also long-term effects such as climate and social impacts.
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Remote Sensing Coastal Change

We use remote-sensing technologies—such as aerial photography, satellite imagery, structure-from-motion (SfM) photogrammetry, and lidar (laser-based surveying)—to measure coastal change along U.S. shorelines.
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Remote Sensing Coastal Change

We use remote-sensing technologies—such as aerial photography, satellite imagery, structure-from-motion (SfM) photogrammetry, and lidar (laser-based surveying)—to measure coastal change along U.S. shorelines.
Learn More