Landslides

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Landslides affect all 50 states and U.S. territories, where they cause 25 to 50 deaths and more than $1 billion in damages each year. Geoscientists study and monitor landslides to identify at-risk areas, prepare populations, and improve our understanding of why, when, and where landslides happen.

Basics

2014 Oso, Washington Landslide. Image Credit: USGS/Photo by Mark Reid

Landslides are masses of earth, rock, or debris that move down slopes. Landslides are triggered by one event, but many causes can weaken slopes over time and make them more likely to fail when there is a triggering event. These causes can be both natural and artificial. Landslides often occur in areas with oversteepened slopes, weak soils/bedrock, or de-vegetated slopes (whether by human deforestation or natural events such as wildfires).[1] Some of the most damaging landslides are triggered by water, typically from intense short-term rainfall or long-term saturation of the slope. Both natural and human activities (such as irrigation or seepage) can saturate hillsides. Earthquakes and volcanic eruptions also cause damaging landslides.[1]   Read more

Frequently Asked Questions

Latest News

IES Soils Glyph
(2019-03-07)
February 14, 2019 Senators Maria Cantwell (D-WA), Lisa Murkowski (R-AK), Cory Gardner (R-CO), Ron Wyden (R-CO), and Dianne Feinstein (D-CA) reintroduced bipartisan legislation to improve the research and coordination needed to help communities prepare for and respond to landslides. The bill, called...
Cracked road from earthquake
(2018-02-06)
January 30, 2018 On January 30, the Senate Committee on Energy and Natural Resources held a full committee hearing to address the role of the U.S. Geological Survey (USGS), U.S. Forest Service (USFS), and National Oceanic and Atmospheric Administration (NOAA) in preparing for and responding to...
landslide
(2017-04-10)
March 22, 2017 Senators Maria Cantwell (D-WA) and Lisa Murkowski (R-AK) introduced the bipartisan National Landslide Preparation Act (S.698) on March 22. The bill directs the U.S. Geological Survey (USGS) to establish a National Landslide Hazards Reduction Program. This program would identify and...
Mount St. Helens
(2016-07-28)
July 12, 2016 The Hazards Caucus Alliance, a network of organizations that promotes nationwide natural disaster resilience, held a briefing to highlight the role that science plays in protecting communities that are vulnerable to lahars. Introductory remarks from Senator Lisa Murkowski (R-AK) were...
Capitol at night
(2016-04-11)
March 17, 2016 Congresswoman Suzan DelBene (D-WA) has introduced new legislation in an effort to decrease losses and damages as a result of landslides.  The new bill, the National Landslide Loss Reduction Act (H.R. 4776) would create the National Landslide Hazards Reduction Program and two...

Case Studies & Factsheets

CI_CaseStudy_2017_1_VolcanicLandslides_thumb.JPG
More than just volcanic eruptions Volcanic eruptions are a serious hazard. But at many stratovolcanoes in Washington, Oregon, Northern California, and Alaska, landslides and debris flows can be just as dangerous. Some of these - especially volcanic mudflows (lahars) - are directly triggered by...
Fig.1. Home in Oakland, CA, destroyed by landslides in 1958. Source: J. Coe, USGS
In California, detailed modern geologic maps are fundamental for evaluating how susceptible an area is to earthquake-induced landslides. Defining the Problem The geologic history of the Oakland, California, area has produced steep hillsides and unstable rock and soil that generate damaging...
Fig. 3. U.S. Highway 85 crossing the Little Missouri River. Seventy-five percent of the rocks in this photograph, all of those in the foreground and the rocks along the north valley wall in the background have slid and are out of place. Credit: E. Murphy
Geologic maps can help to show which areas may be more prone to landslides and therefore directly assist in making optimum engineering design choices. Defining the Problem U.S Highway 85 and ND Highway 22, along with numerous county roads, buildings, pipelines, and power lines, have been...
Fig. 1. Homeowners and emergency managers are still coping with debris flows and the aftermath of the 2002 Missionary Ridge wildfire near Durango, CO. Credit: P. Winkworth
Geologic maps are useful in identifying areas that may be affected by post-wildfire debris flows. Land-use planners use these maps to identify potential hazards in areas that are proposed for development and to develop mitigation strategies. The maps can also focus post-wildfire emergency planning...
Fig. 1. A 1995 landslide in Overland Park, Kansas, destroyed two homes and damaged four lots. Credit: Kansas Geological Survey
Landslide hazard maps based on geologic maps are a tool for local government officials, planners, developers, engineers, insurance companies, lending institutions, and landowners to assess the risk and take appropriate actions. Defining the Problem Damaging landslides occur even in vertically...
Cover of AGI Factsheet 2018-003--Using Geologic Maps to Reduce Landslide Risk
Geologic Maps and Landslide Hazards A geologic map is key to understanding landslide risk. The U.S. Geological Survey (USGS) and numerous state geological surveys around the nation prioritize the mapping of landslide-prone areas. Understanding landslide risk is crucial in making decisions around...

GOLI Online Courses

Landslides and Mass Wasting
Course Type: GOLI Online Course

This course is designed to be an introduction to the subject of landslides or mass wasting. Landslides or mass wasting occur in both solid bedrock and in poorly-consolidated sediments. Concerning the latter, loose sands, clays and soft shales can prove to be quite problematic. These type of...

Geological Surveys Database Publications

2000, United States Geological Survey
Landslide hazards occur in many places around What Can You Do If You Live Near Steep Hills? the world and include fast-moving debris flows, slow-moving landslides, and a variety of flows and slides initiating from volcanoes. Each year, these hazards cost billions of dollars and cause numerous...
1995, Ohio Geological Survey

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2001, Pennsylvania Geological Survey
Landslides are a natural geologic process that can also be a significant geologic hazard. In this well-illustrated booklet, one can learn what causes landslides, how they are classified, the damages that can result and their associated costs, and the prevention measures that can be taken.
1987, Maine Geological Survey

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2009, Maine Geological Survey

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2009, Maine Geological Survey

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2009, Maine Geological Survey

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2009, Maine Geological Survey

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2009, Maine Geological Survey

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2009, Maine Geological Survey

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