Earthquake Hazards Program

Title: Underwater Secrets of the Hayward Fault Zone: Integrated 3D imaging to understand earthquake hazards 

• Underwater imaging provides a unique opportunity to study urban fault hazards.
• How do we link surface structures to depths where earthquakes occur?
• How does "acoustic trenching" help us understand earthquake history?

Shaking during the 1964 Alaska earthquake was felt as far away as Seattle, Washington, and its tsunamis caused 129 fatalities and about $2.3 billion in property losses (2013 dollars). This massive shift of the Pacific Plate also caused widespread, permanent land-level changes, which are still visible at Girdwood, Alaska, where the land dropped almost 2 meters (6.6 feet);

Interviews with staff at Point Reyes National Seashore tell how this National Park Service unit uses USGS science to educate visitors, and manage the park.
 

USGS Research Geophysicist Kate Allstadt conducts experiments at the U.S. Geological Survey debris-flow flume, near Eugene, Oregon. Dr. Allstadt and her group are working toward an understanding of how debris flows generate seismic signals. The quantitative information will be used in the development of improved technologies for detecting debris flows to mitigate their

View of Glacier Bay National Park from the air.

USGS research geologist Kate Scharer with her finger on the Fairweather Fault in southeast Alaska. The magnitude 7.8 Lituya Bay earthquake caused shaking that toppled trees along the fault, which left a break in the forest shown here.

Nearly 60 years after a magnitude 7.7 earthquake struck Lituya Bay, Alaska — leading to a tsunami that devastated the area — six U.S. Geological Survey geologists revisited the isolated region of Alaska, to pick up where their scientific predecessors left off. In this photo, members of the USGS research team pause to take in the view of South Crillon Glacier from a study

Periodic calving of ice from the snout of South Crillon Glacier.

Trench site along the southern Fairweather Fault, in Glacier Bay National Park, Alaska. The alluvial fan at left consists of lake, stream channel and debris flow deposits impounded by the Fairweather Fault scarp, at right.

The field team included USGS geologists Rob Witter, Adrian Bender, Chris DuRoss, Peter Haeussler, Richard Lease and Kate Scharer

This video presents a visualization of shaking that was recorded in the Frontier Building in Anchorage, Alaska, during the Mw7.1 earthquake, January 24, 2016, Iniskin, Alaska. It exhibits how a tall building behaves and performs during strong earthquake shaking. Note that relative to the height of the building, the motions are magnified by a factor of 300 to show