Landslide hazard susceptibility mapping in Homer, Alaska, Report of Investigation 2024-3, provides a map and database of historical and prehistoric slope failures, maps of shallow and deep-seated landslide susceptibility, and a map of simulated debris flow runouts for the City of Homer, Alaska and nearby populated areas including Kachemak City and Millers Landing. The landslide inventory map integrates existing maps of landslides caused by the 1964 Great Alaska Earthquake and newly mapped slope failures identified in sequences of aerial photos since 1950 and high-resolution light detection and ranging (lidar) data collected for this project. The Alaska Division of Geological & Geophysical Surveys (DGGS) staff created a shallow landslide susceptibility map following protocols like those developed by the Oregon Department of Geology and Mineral Industries, which includes incorporating landslide inventory data, geotechnical soil properties, and lidar-derived topographic slope to calculate the Factor of Safety (FOS), which serves as a proxy for landslide susceptibility. Debris flow runout extents were generated using the model Laharz, which simulates runout extents based on catchment-specific physical parameters (e.g., hypothetical sediment volumes). Data from these analyses are collectively intended to depict locations where landslides are relatively more likely to occur or are relatively more likely to travel. The results provide important hazard information that can help guide planning and future risk investigations. The maps are not intended to predict slope failures and are site-specific; detailed investigations should be conducted before development in vulnerable areas. Results are for informational purposes and are not intended for legal, engineering, or surveying uses. These data and the interpretive maps and report are available from the DGGS website: http://doi.org/10.14509/31155.

Digital representation of the Eugene Landslide Hazard Map for informational purposes only. For the official version adopted as part of the Clear & Objective Housing Approval Criteria Update, contact City staff at 541-682-5377. For more information about the Clear & Objective Housing Approval Criteria Update visit: https://www.eugene-or.gov/3947/Clear-Objective.Terms of UseThis product is for informational purposes and may not have been prepared for, or be suitable for legal, engineering, or surveying purposes. This digital layer does not constitute the adopted Eugene Landslide Hazard Map, and users of this information should review or consult the primary data and information sources to ascertain the usability of this information. To verify information presented in this layer, contact the Planner-on-Duty at 541-682-5377.The maps and data available for access from the City of Eugene are provided "as is" without warranty or any representation of accuracy, timeliness or completeness. The burden for determining accuracy, completeness, timeliness, merchantability and fitness for or the appropriateness for use rests solely on the user accessing this information. The City of Eugene makes no warranties, expressed or implied, as to the use of the maps and data available for access at this website. There are no implied warranties of merchantability or fitness for a particular purpose. The user acknowledges and accepts all inherent limitations of the maps and data, including the fact that the maps and data are dynamic and in a constant state of maintenance, correction and revision. Any maps and associated data for access do not represent a survey. No liability is assumed for the accuracy of the data delineated on any map, either expressed or implied.

The Landslide Susceptibility Index was developed by Response Directorate FEMA Mitigation Division and the Department of Homeland Security Emergency reparedness in order to determine levels of landslide risks according to a eographical region. Parameters analyzed in this index include geologic group types and their compositions' level of rigidity, groundwater levels, and topography (slope).These indices were calculated and then separated into three geologic groups ( Strong, Weak, Agrillaceous) and compared to groundwater levels to determine which areas were either dry or wet. Finally, this data was evaluated alongside slope degrees, determining the final hazard index.

A map used in the Hazard Risk Assessment Maps app and the Hazard Explorer app to visualize landslide hazards.

This layer is displayed on the Landslide hazard overlay map in City Plan version 7 as 'Landslide hazard moderate', 'Landslide hazard high', and 'Landslide hazard very high'. The layer is also available in Council’s City Plan interactive mapping tool. For further information on City Plan, please visit http://www.goldcoast.qld.gov.au/planning-and-building/city-plan-2015-19859.html

A map used in the Hazard Risk Assessment Maps app and the Hazard Explorer app to visualize landslide hazards.

This landslide susceptibility mapping study is a requirement of the Bay of Plenty Regional Policy Statement. The methodology of the study is generally based on the “basic” level assessment described in the Australian Geomechanics Society Guideline for Landslide Susceptibility, Hazard and Risk Zoning (AGS, 2007a).The study area consists of the Bay of Plenty regional boundary, excluding the Tauranga City district and five other areas where landslide susceptibility studies have previously been carried out or are currently being undertaken. It also includes the part of the Rotorua Lakes District that lies within the Waikato region. The geology, geomorphology and characteristic mechanisms of landsliding across the study area are described, based on the results of a literature review of available information. Factors that influence slope stability are identified from the results of the literature review, including correlation to an inventory of previous landslides. Assessment of the landslide susceptibility is based on weighting of the influencing factors and combining these in Geographical Information System (GIS) platform using available geospatial datasets. Four categories of landslide susceptibility are described, from Very Low to High, and these are mapped across the region in GIS showing the spatial distribution and extent of the different susceptibility categories. The maps do not present potential areas of regression and runout of landslide debris, which have not been assessed at this stage. The region was mapped at a 1:50,000 scale, except for urban areas identified by BOPRC, which were mapped at 1:25,000. The maps should be used at appropriate scales suggested, and were made available to the public through the Council natural hazards GIS viewer, the scale should be restricted to 1:25,000 for the 12 identified Urban Areas, and 1:50,000 for the remainder of the region.

This is a digital Seismic Hazard Zone Map presenting areas where liquefaction and landslides may occur during a strong earthquake. Three types of geological hazards, referred to as seismic hazard zones, may be featured on the map: 1) liquefaction, 2) earthquake-induced landslides, and 3) overlapping liquefaction and earthquake-induced landslides. In addition, a fourth feature may be included representing areas not evaluated for liquefaction or earthquake-induced landslides. Developers of properties falling within any of the three zones may be required to investigate the potential hazard and mitigate its threat during the local permitting process.

We present a preliminary point inventory of landslides triggered by Hurricane Helene, which impacted southern Appalachia between September 25–27, 2024. This inventory is a result of a rapid response mapping effort led by the U.S. Geological Survey’s Landslide Assessments, Situational Awareness, and Event Response Research (LASER) project. LASER collaborated with state surveys and landslide researchers to identify landslides and their impacts for situational awareness and emergency response. The area of interest (AOI) for this effort was informed by a preliminary landslide hazard map created for the event (Martinez et al., 2024), and encompasses western North Carolina as well as parts of Tennessee, Virginia, Georgia, and South Carolina. This point inventory contains the following attributes: ‘Source’ and ‘Impact’. The ‘Source’ attribute identifies the data source(s) used to map each landslide. Note that the data sources listed in this attribute refer only to those used for mapping a given landslide; this does not imply that the landslide is absent or undocumented in other unlisted sources. We do not provide any specific information or metadata (e.g., footprint ID, imagery date, hyperlinks, etc.) for the listed source(s) used to map a landslide. The sources used for mapping landslides in this inventory are listed in Table 1. We relied heavily on Sentinel-2 satellite data during the mapping phase and exclusively during the review phase. While Sentinel-2 has a lower spatial resolution (10m) compared to other satellite and aerial sources (ranging from 0.15 to 3m), it is the only dataset with complete mapping AOI coverage and pre- and post-event multi-spectral imagery. The primary Sentinel-2 images used were acquired on August 26, 2024, and September 22, 2024 (pre-event), as well as October 2, 5, 7, 10, and 12, 2024 (post-event). To assist in rapid landslide detection, we derived Normalized Difference Vegetation Index (NDVI) change products using various combinations of the pre- and post-event Sentinel-2 data. NDVI change analysis was instrumental in identifying areas where vegetation loss or damage occurred, thus helping to pinpoint potential landslide activity in this heavily vegetated region. Additionally, red-green-blue (RGB) composite imagery from both pre- and post-event acquisitions was used to validate that NDVI changes were indeed indicative of landslides. Details on these data sources and analysis methods area can be found in Burgi et al. (2024). The data sources listed in the ‘Source’ attribute listed in alphabetical order. The ‘Impact’ attribute indicates the primary impact of a landslide. The options for the impact attribute are listed in Table 2. A landslide is deemed to have an impact if it appears to intersect with river(s) (including streams and creeks), road(s), building(s), or other human-modified land or infrastructure (e.g., bridges, railroads, powerlines, trails, agricultural fields, lawns, etc.) Impact was determined to the best of a mapper’s ability with the available data and at the time that the imagery was acquired. Many landslides had multiple impacts; however, in most cases, a primary impact could be identified. For example, many landslides appeared to severely impact a road and continue to fail into a nearby river, with no visible impact on the river. In this case, the primary impact would be “road”. If a landslide appeared to have multiple and equally significant impacts, it was classified as “various”. We do not report the number of impacts; for example, a landslide with a “building” Impact may have impacted more than one building. Emergency response landslide mapping efforts took place between September 28 to October 23, 2024. All landslides were mapped with a single point, irrespective of size or impact. Given the urgency of providing situational awareness for emergency response, landslide points were placed at the location of greatest visible impact, such as buildings, roads, and rivers, rather than at the headscarp. In cases where there was no visible impact, the landslide point was placed at the headscarp. Following the emergency mapping phase, all points underwent a basic review process to refine attributes, remove duplicate/low confidence points, add points for multi-source failures that coalesced into a single failure, and, where possible, adjust point locations from impact zones to the landslide headscarp(s). Reviewers utilized only Sentinel-2 NDVI and RGB imagery (pre- and post-event) for reference during the review process, relying most heavily on the 9/22 pre-event and 10/12 post-event products. Impactful landslides that are not clearly visible in the Sentinel-2 data (likely mapped using higher resolution data) were not repositioned to a headscarp and may remain at the impact location. Due to the rapid and extensive nature of this mapping effort, a formal and systematic assessment of the positional accuracy of the mapped points has not yet been conducted. As a result, there may be some degree of uncertainty in the location and classification of landslides within this inventory. We estimate our accuracy of most landslide headscarp points to be within tens of meters of their correct location. However, in some cases, dense vegetation and imaging geometry may obscure the true headscarp location, further decreasing the accuracy of some mapped landslide points. Furthermore, field or high-resolution validation was not possible for every landslide, therefore some mapped points may not correspond to actual landslide events. In particular, distinguishing landslides from severe tree blowdowns or areas of recently human-modified land cover (e.g., clearcutting or construction activities) sometimes proved challenging. It is possible that a small number of points mistakenly represent these features instead of genuine landslides. Finally, it is important to note that this inventory is preliminary and does not capture the full extent of landslides triggered by Hurricane Helene. Factors such as the rapid response nature of the mapping effort, limitations in imagery resolution, and dense forest canopy that obstructed the overhead (i.e., aerial and satellite) view of smaller or non-catastrophic landslides may contribute to underrepresentation of the total landslide count. References Burgi, P.M., Collins, E.A., Allstadt, K.E., Einbund, M.M., 2024, Normalized Difference Vegetation Index (NDVI) Change Map between 9/22/2024 and 10/12/2024, Southern Appalachian Mountains: 2024 USGS provisional data release. https://doi.org/10.5066/P14KDUKK Martinez, S.N., Stanley, T., Allstadt, K.E., Baxstrom, K.W., Mirus, B.B., Einbund, M.M., Bedinger, E.C., 2024, Preliminary Landslide Hazard Models for the 2024 Hurricane Helene Landslide Emergency Response: 2024 USGS Provisional Data Release. https://doi.org/10.5066/P134ERB9

Geospatial data about Los Angeles County Landslide Zones. Export to CAD, GIS, PDF, CSV and access via API.

To better understand factors potentially contributing to the occurrence of rainfall-induced landslides in Puerto Rico, we evaluated the locations of landslides there following Hurricane Maria (Hughes et al., 2019) and potential contributing factors. This data release provides results of evaluations of landslide locations compared to soil classification and land cover, which involved frequency-ratio analyses (for example, Lee and Pradhan, 2006; Lee et al., 2007; He and Beighley, 2008; Lepore et al., 2012; Chalkias et al., 2014). Soil classification data were obtained from the U.S. Department of Agriculture Natural Resources Conservation Service (2018) and land cover data were obtained from the Puerto Rico Gap Analysis Program (Gould et al., 2008). The data presented herewith were produced during a study described in Hughes, K.S., and Schulz, W.H., ####, Map depicting susceptibility to landslides triggered by intense rainfall, Puerto Rico: U.S. Geological Survey Open-file Report #####. Three files are included with this data release. Data files soil_classification_results.csv and land_cover_results.csv provide results of the analyses of landslide locations compared to soil classification and land cover, respectively. A read-me file (readme.txt) provides the information contained in this summary and additional description of data available from the data files. References Chalkias, C., Kalogirou, S., and Ferntinou, M., 2014, Landslide susceptibility, Peloponnese Peninsula in South Greece: Journal of Maps, v. 10, no. 2, p. 211-222. Gould, W.A., Alarcón, C., Fevold, B., Jiménez, M.E., Martinuzzi, S., Potts, G., Quiñones, M., Solórzano, M., and Ventosa, E., 2008, The Puerto Rico Gap Analysis Project. Volume 1: Land cover, vertebrate species distributions, and land stewardship. Gen. Tech. Rep. IITF-GTR-39. Río Piedras, PR: U.S. Department of Agriculture, Forest Service, International Institute of Tropical Forestry. 165 p. https://www.sciencebase.gov/catalog/item/560c3b2de4b058f706e5411e. Last accessed 12 September 2019. He, Y., and Beighley, R.E., 2008, GIS‐based regional landslide susceptibility mapping: a case study in southern California: Earth Surface Processes and Landforms, v. 33, no. 3, p. 380-393. Hughes, K.S., Bayouth García, D., Martínez Milian, G.O., Schulz, W.H., and Baum, R.L., 2019, Map of slope-failure locations in Puerto Rico after Hurricane María: U.S. Geological Survey data release: https://doi.org/10.5066/P9BVMD74. https://www.sciencebase.gov/catalog/item/5d4c8b26e4b01d82ce8dfeb0. Last accessed 12 September 2019. Lee, S., and Pradhan, B., 2006, Probabilistic landslide hazards and risk mapping on Penang Island, Malaysia: Journal of Earth System Science, v. 115, no. 6, p. 661-672. Lee, S., Ryu, J-H., and Kim, I-S., 2007, Landslide susceptibility analysis and its verification using likelihood ratio, logistic regression, and artificial neural network models: case study of Youngin, Korea: Landslides v. 4, p. 327–338. Lepore, C., Kamal, S.A., Shanahan, P., and Bras, R.L., 2012, Rainfall-induced landslide susceptibility zonation of Puerto Rico: Environmental Earth Sciences, v. 66, p. 1667-1681. U.S. Department of Agriculture Natural Resources Conservation Service, 2018, Soil Survey Geographic (SSURGO) database for Puerto Rico, all regions: https://websoilsurvey.sc.egov.usda.gov/App/WebSoilSurvey.aspx. Last accessed 12 September 2019.

This map shows the relative likelihood of deep landsliding based on regional estimates of rock strength and steepness of slopes. On the most basic level, weak rocks and steep slopes are more likely to generate landslides. This shows the distribution of one very important component of landslide hazard. It is intended to provide infrastructure owners, emergency planners and the public with a general overview of where landslides are more likely. The map does not include information on landslide triggering events, such as rainstorms or earthquake shaking, nor does it address susceptibility to shallow landslides such as debris flows. This map is not appropriate for evaluation of landslide potential at any specific site.

For visualization: If gridcode is 8,9,10 than area is High Susceptibility for landslides

Landslide susceptibility maps are essential tools in infrastructure planning, hazard mitigation, and risk reduction. Susceptibility maps trained in one area have been found to be unreliable when applied to different areas (Woodard et al., 2023). This limitation leads to the need for a national map that is higher resolution and rigorous, but simple enough to be applied to diverse terrains and landslide types. The susceptibility maps presented here cover the conterminous United States (CONUS), Alaska (AK), Hawaii (HI), and Puerto Rico (PR) with a resolution of 90-m. Other United States (U.S.) territories were not considered due to insufficient landslide and digital elevation data. We also provide information on the proportion of susceptible terrain as well as the density (landslides per square kilometer) of documented landslides within susceptible terrain for each U.S. county. To generate the susceptibility maps we used 1/3 arc-second digital elevation models (DEMs) (U.S. Geological ...

This layer is a component of Web server for AP and SHZ zones.

This is a digital Seismic Hazard Zone Map presenting areas where liquefaction and landslides may occur during a strong earthquake. Three types of geological hazards, referred to as seismic hazard zones, may be featured on the map: 1) liquefaction, 2) earthquake-induced landslides, and 3) overlapping liquefaction and earthquake-induced landslides. In addition, a fourth feature may be included representing areas not evaluated for liquefaction or earthquake-induced landslides. Developers of properties falling within any of the three zones may be required to investigate the potential hazard and mitigate its threat during the local permitting process.

© Seismic Hazards Progam, California Geological Survey, California Department of Conservation

Landslide Inventory and Hazard Mapping for St. Lucia and Grenada.

This dataset is one of the products produced under the 2014-2016 World Bank (WBG) - European Space Agency (ESA) partnership, and is published in the partnership report: Earth Observation for Sustainable Development, June 2016.

A compliant implementation of WMS plus most of the SLD extension (dynamic styling). Can also generate PDF, SVG, KML, GeoRSS

Areas that are in risk for landslides. Based on analysis from MOE. The accuracy and resolution of the data is unknown.

This area has been categorized as a potential landslide hazard area. The map does not purport to identify actual landslide hazards or existing landslide risks for specific properties. Depending upon the nature of any proposed development, further investigation of the site and a detailed evaluation of the landslide hazard by a licensed geological engineer or engineering geologist may be recommended or even required. The information included on this map is subject to change without notice. King County makes no representations or warranties, expressed or implied, as to accuracy, completeness, timeliness, or rights to the use of such information. King County shall not be liable for any errors, omissions, or inaccuracies in such information regardless of their cause, and King County shall not be liable for any decision made, action taken, or action not taken by the user in reliance upon such information. This document is not intended for use as a surveyed product. King County shall not be liable for any general, special, indirect, incidental, or consequential damages including, but not limited to, lost revenues or lost profits resulting from the use or misuse of the information contained on this map. Any sale of this map is prohibited except by written permission of King County.http://www.kingcounty.gov/~/media/operations/GIS/documents/DPER-LS-hazard-map-disclaimer.aspx

Landslides are damaging and deadly, and they occur in every U.S. state. However, our current ability to understand landslide hazards at the national scale is limited, in part because spatial data on landslide occurrence across the U.S. varies greatly in quality, accessibility, and extent. Landslide inventories are typically collected and maintained by different agencies and institutions, usually within specific jurisdictional boundaries, and often with varied objectives and information attributes or even in disparate formats. The purpose of this data release is to provide an openly accessible, centralized map of existing information on landslide occurrence across the entire U.S. The data release includes digital inventories created by both USGS and non-USGS authors. It provides an integrated database of all the landslides with a selection of uniform attributes, but also includes links to the original digital inventory files (whenever available). Given the wide range of landslide i ...

The Global Rainfall-Triggered Landslide Hazard Map presents a quantitative representation of landslide hazard. This component is the mean annual rainfall-triggered landslide hazard assessment for the period 1980 – 2018. Raster values represent the modelled average annual frequency of significant rainfall-triggered landslides per sq. km.