Geology Reports⌕ Search

SEARCH · Geology Reports

Results for “GeoHazards”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources
USGS2018

Towards coordinated regional multi-satellite InSAR volcano observations: Results from the Latin America pilot project

Within Latin America, about 319 volcanoes have been active in the Holocene, but 202 of these volcanoes have no seismic, deformation or gas monitoring. Following the 2012 Santorini Report on satellite Earth Observation and Geohazards, the Committee on Earth Observation Satellites (CEOS) developed a 4-year pilot project (2013-2017) to demonstrate how satellite observations can be used to monitor large numbers of volcanoes cost-effectively, particularly in areas with scarce instrumentation and/or difficult access. The pilot aims to improve disaster risk management (DRM) by working directly with the volcano observatories that are governmentally responsible for volcano monitoring as well as with the international space agencies (ESA, CSA, ASI, DLR, JAXA, NASA, CNES). The goal is to make sure that the most useful data are collected at each volcano following the guidelines of the Santorini report that observation frequency is related to volcano activity, and to communicate the results to the local institutions in a timely fashion. Here we highlight how coordinated multi-satellite observations have been used by volcano observatories to monitor volcanoes and respond to crises. Our primary tool is measurements of ground deformation made by Interferometric Synthetic Aperture Radar (InSAR), which have been used in conjunction with other observations to determine the alert level at these volcanoes, served as an independent check on ground sensors, guided the deployment of ground instruments, and aided situational awareness. During this time period, we find 26 volcanoes deforming, including 18 of the 28 volcanoes that erupted - those eruptions without deformation were less than 2 on the VEI scale. Another 7 volcanoes were restless and the volcano observatories requested satellite observations, but no deformation was detected. We describe the lessons learned about the data products and information that are most needed by the volcano observatories in the different countries using information collected by questionnaires. We propose a practical strategy for regional to global satellite volcano monitoring for use by volcano observatories in Latin America and elsewhere to realize the vision of the Santorini report.

Journal of Applied Volcanology↗
USGS2001

Geographic deaggregation of seismic hazard in the United States

The seismic hazard calculations for the 1996 national seismic hazard maps have been geographically deaggregated to assist in the understanding of the relative contributions of sources. These deaggregations are exhibited as maps with vertical bars whose heights are proportional to the contribution that each geographical cell makes to the ground-motion exceedance hazard. Bar colors correspond to average source magnitudes. We also extend the deaggregation analysis reported in Harmsen et al. (1999) to the western conterminous United States. In contrast to the central and eastern United States (CEUS); the influence of specific faults or characteristic events can be clearly identified. Geographic deaggregation for 0.2-sec and 1.0-sec pseudo spectral acceleration (SA) is performed for 10% probability of exceedance (PE) in 50 yr (475-yr mean return period) and 2% PE in 50 yr (2475-yr mean return period) for four western U.S. cities, Los Angeles, Salt Lake City, San Francisco, and Seattle, and for three central and eastern U.S. cities, Atlanta, Boston, and Saint Louis. In general, as the PE is lowered, the sources of hazard closer to the site dominate. Larger, more distant earthquakes contribute more significantly to hazard for 1.0-sec SA than for 0.2-sec SA. Additional maps of geographically deaggregated seismic hazard are available on the Internet for 120 cities in the conterminous United States (http://geohazards. cr.usgs.gov/eq/) for 1-sec SA and for 0.2-sec SA with a 2% PE in 50 yr. Examination of these maps of hazard contributions enables the investigator to determine the distance and azimuth to predominant sources, and their magnitudes. This information can be used to generate scenario earthquakes and corresponding time histories for seismic design and retrofit. Where fault density is lower than deaggregation cell dimensions, we can identify specific faults that contribute significantly to the seismic hazard at a given site. Detailed fault information enables investigators to include rupture information such as source directivity, radiation pattern, and basin-edge effects into their scenario earthquakes used in engineering analyses.

Bulletin of the Seismological Society of America↗
USGS2025

Searching for seismic precursors - The Barry Landslide hazard clean up

The Barry Landslide, located in Barry Arm of Prince William Sound, Alaska, poses a major hazard due to its steep, unstable slopes and the potential for a massive landslide-generated tsunami. With an estimated volume of 500–700 million cubic meters, the Barry Landslide could trigger highly destructive waves. In this study, we focus on seismic signals from the Barry Landslide, which are critical for providing timely tsunami warnings. Since the summer of 2020, the region has been instrumented to monitor the landslide, but the seismic record is complicated by the presence of nearby glaciers and frequent regional earthquakes. Among these signals, we analyze a specific class of short-duration, high-frequency seismic events that exhibit strong seasonal variability, increasing in rate from late summer to mid-winter before ceasing abruptly in late winter or early spring. Our analysis suggests that the source of these signals is likely near or beneath Cascade Glacier, adjacent to the landslide, rather than within the landslide mass itself. We apply detection algorithms to construct a time history for this signal type, which we then compare with environmental factors like precipitation, temperature, and slope displacement data from ground-based radar and remote sensing. Correlations indicate that these seismic events may be driven by seasonal hydrological changes, particularly the freeze-up of subglacial water pathways. While these events are not directly linked to landslide motion, they serve as indirect markers of subsurface hydrological conditions that influence slope stability. Our findings highlight the complex interplay between glaciers, groundwater, and landslide dynamics, emphasizing the need for multi-parameter monitoring to assess evolving geohazards in the region.

Alaska↗
USGS2019

The Santa Cruz Basin submarine landslide complex, southern California: Repeated failure of uplifted basin sediment

The Santa Cruz Basin (SCB) is one of several fault-bounded basins within the California Continental Borderland that has drawn interest over the years for its role in the tectonic evolution of the region, but also because it contains a record of a variety of modes of sedimentary mass transport (i.e., open slope vs. canyon-confined systems). Here, we present a suite of new high-resolution marine geophysical data that demonstrate the extent and significance of the SCB submarine landslide complex in terms of late Miocene to present basin evolution and regional geohazard assessment. The new data reveal that submarine landslides cover an area of ~160 km2 along the eastern flank of the Santa Rosa–Cortes Ridge and have emplaced a minimum of 9 to 16 km3 of mass transport deposits along the floor of the SCB during the Quaternary. The failures occur along an onlapping wedge of Pliocene sediment that was uplifted and tilted during the later stages of basin development. The uplifted and steepened Pliocene strata were preconditioned for failure so that parts of the section failed episodically throughout the Quaternary—most likely during large earthquakes. Once failed, the material initially translated as a block glide along a defined failure surface. As transport continued several kilometers across a steep section of the lower slope, the material separated into distinctive proximal and distal components. The failed masses mobilized into debris flows that show evidence for dynamic separation into less and more mobile components that disturbed and eroded underlying stratigraphy in areas most proximal to the source area. The most highly mobilized components and those with the lowest viscosity and yield strength produced flows that blanket the underlying stratigraphy along the distal reaches of deposition. The estimated volumes of individual landslides within the complex (0.1–2.6 km3), the runout distance measured from the headwalls (>20 km), and evidence for relatively high velocity during initial mobilization all suggest that slides in the SCB may have been tsunamigenic. Because many slopes in the California Continental Borderland are either sediment starved or have experienced sediment bypass during the Quaternary, we propose that uplift and rotation of Pliocene deposits are important preconditioning factors for slope failure that need to be systematically evaluated as potential tsunami initiators.

California↗
USGS2020

Evidence for large Holocene earthquakes along the Denali fault in southwest Yukon, Canada

The Yukon–Alaska Highway corridor in southern Yukon is subject to geohazards ranging from landslides to floods and earthquakes on faults in the St. Elias Mountains and Shakwak Valley. Here we discuss the late Holocene seismic history of the Denali fault, located at the eastern front of the St. Elias Mountains and one of only a few known seismically active terrestrial faults in Canada. Holocene faulting is indicated by scarps and mounds on late Pleistocene drift and by tectonically deformed Pleistocene and Holocene sediments. Previous work on trenches excavated against the fault scarp near the Duke River reveals paleoseismic sediment disturbance dated to ∼300–1,200, 1,200–1,900, and 3,000 years ago. Re-excavation of the trenches indicates a fourth event dated to 6,000 years ago. The trenches are interpreted to show a negative flower structure produced by extension of sediments by dextral strike-slip fault movement. Nearby Crescent Lake is ponded against the fault scarp. Sediment cores reveal four abrupt sediment and diatom changes reflecting seismic shaking at ∼1,200–1,900, 1,900–5,900, 5,900–6,200, and 6,500–6,800 years ago. At the Duke River, the fault offsets sediments, including two White River tephra layers (∼1,900 and 1,200 years old). Late Pleistocene outwash gravel and overlying Holocene aeolian sediments show in cross section a positive flower structure indicative of post-glacial contraction of the sediments by dextral strike-slip movement. Based on the number of events reflecting ∼M6, we estimate the average recurrence of large earthquakes on the Yukon part of the Denali fault to be about 1,300 years in the past 6,500–6,800 years.

Yukon↗
USGS1981

The U.S. Geological Survey in Alaska; 1981 programs

This Circular describes the 1981 programs and projects of the U.S. Geological Survey in Alaska. A brief description of the Alaskan operations of each office and division of the Survey is followed by project descriptions arranged by geographic regions in which the work takes place. The largest program at present is related to oil and gas exploration, but programs also include mineral appraisal, water-resource studies, volcanic and seismic programs, topographic mapping, glaciological and geohazard studies, and many other activities. Alaska is the largest and the least populated, least explored, and least developed of the Nation 's States. The land area contains 375 million acres and comprises 16 percent of the onshore land and more than half of the Outer Continental Shelf of the Nation. After Native and State of Alaska land selections of 44 million acres have been made, approximately 60 percent, 225 million acres, of Alaska land will remain under Federal jurisdiction. Federal lands in Alaska then will comprise approximately 30 percent of all onshore land in the Nation 's public domain. (USGS)

Circular↗
USGS2007

Thermal properties of methane gas hydrates

Gas hydrates are crystalline solids in which molecules of a “guest” species occupy and stabilize cages formed by water molecules. Similar to ice in appearance (fig. 1), gas hydrates are stable at high pressures and temperatures above freezing (0°C). Methane is the most common naturally occurring hydrate guest species. Methane hydrates, also called simply “gas hydrates,” are extremely concentrated stores of methane and are found in shallow permafrost and continental margin sediments worldwide. Brought to sea-level conditions, methane hydrate breaks down and releases up to 160 times its own volume in methane gas. The methane stored in gas hydrates is of interest and concern to policy makers as a potential alternative energy resource and as a potent greenhouse gas that could be released from sediments to the atmosphere and ocean during global warming. In continental margin settings, methane release from gas hydrates also is a potential geohazard and could cause submarine landslides that endanger offshore infrastructure. Gas hydrate stability is sensitive to temperature changes. To understand methane release from gas hydrate, the U.S. Geological Survey (USGS) conducted a laboratory investigation of pure methane hydrate thermal properties at conditions relevant to accumulations of naturally occurring methane hydrate. Prior to this work, thermal properties for gas hydrates generally were measured on analog systems such as ice and non-methane hydrates or at temperatures below freezing; these conditions limit direct comparisons to methane hydrates in marine and permafrost sediment. Three thermal properties, defined succinctly by Briaud and Chaouch (1997), are estimated from the experiments described here: - Thermal conductivity , λ: if λ is high, heat travels easily through the material. - Thermal diffusivity , κ: if κ is high, it takes little time for the temperature to rise in the material. - Specific heat , c p : if c p is high, it takes a great deal of heat to raise the temperature of the material.

Fact Sheet↗
USGS2026

Bascom Laser Diffraction Sedimentology Laboratory, Reston, Virginia

Introduction At the Bascom Laser Diffraction Sedimentology Laboratory, which is located in the Florence Bascom Geoscience Center at U.S. Geological Survey (USGS) headquarters in Reston, Virginia, scientists use physical sedimentology and particle characterization techniques to conduct detailed sediment characterization. Scientists address research problems in collaboration with other USGS science centers, State geological surveys, commercial industry, universities, and other partners. Laboratory capabilities include laser diffractometry for quantitative particle-size analysis, portable x-ray fluorescence (XRF) analysis for determining elemental abundances in rock or sediment samples, petrographic analysis of geologic media, and mechanical sieve analysis. These methods are used to analyze soil and sediment core material from terrestrial, marine, and lacustrine environments, surface sediments from coastal regions, and calcareous materials. Work done by the laboratory supports geologic mapping, resource assessments, land change studies, and geohazard analyses.

Fact Sheet↗
USGS2000

Possible costs associated with investigating and mitigating geologic gazards in rural areas of western San Mateo County, California

This publication consists of a digital map database on a geohazards web site, http://kaibab.wr.usgs.gov/geohazweb/intro.htm, this text, and 43 digital map images available for downloading at this site. The report is stored as several digital files, in ARC export (uncompressed) format for the database, and Postscript and PDF formats for the map images. Several of the source data layers for the images have already been released in other publications by the USGS and are available for downloading on the Internet. These source layers are not included in this digital database, but rather a reference is given for the web site where the data can be found in digital format. The exported ARC coverages and grids lie in UTM zone 10 projection. The pamphlet, which only describes the content and character of the digital map database, is included as Postscript, PDF, and ASCII text files and is also available on paper as USGS Open-File Report 00-127. The full versatility of the spatial database is realized by importing the ARC export files into ARC/INFO or an equivalent GIS. Other GIS packages, including MapInfo and ARCVIEW, can also use the ARC export files. The Postscript map image can be used for viewing or plotting in computer systems with sufficient capacity, and the considerably smaller PDF image files can be viewed or plotted in full or in part from Adobe ACROBAT software running on Macintosh, PC, or UNIX platforms.

California↗
USGS2002

Multibeam mapping of the Los Angeles, California Margin

The Los Angeles, California Margin was mapped using multibeam echosounders during three separate surveys (Figure 1). In 1996, the USGS surveyed the shelf and slope in Santa Monica Bay from Pt. Dume to south of the Palos Verdes Peninsula. The mapping was accomplished using a Kongsberg Simrad EM1000 multibeam sonar system that provided high-quality bathymetry and quantitative backscatter. In 1998, the USGS continued the mapping to the south and surveyed the outer shelf, slope, and proximal basin off Long Beach and Newport using a Kongsberg Simrad EM300 multibeam sonar system. In 1999, the Los Angeles Margin mapping was completed with the surveying of the inner Long Beach shelf from the Palos Verdes Peninsula, south to Newport. This survey used a dual Kongsberg Simrad EM3000D multibeam sonar system. These three surveys were conducted to support USGS projects studying marine pollution and geohazards along the Los Angeles Margin.

California↗
USGS2002

A bibliography of terrain modeling (geomorphometry), the quantitative representation of topography: Supplement 4.0

Terrain modeling, the practice of ground-surface quantification, is an amalgam of Earth science, mathematics, engineering, and computer science. The discipline is known variously as geomorphometry (or simply morphometry), terrain analysis, and quantitative geomorphology. It continues to grow through myriad applications to hydrology, geohazards mapping, tectonics, sea-floor and planetary exploration, and other fields. Dating nominally to the co-founders of academic geography, Alexander von Humboldt (1808, 1817) and Carl Ritter (1826, 1828), the field was revolutionized late in the 20th Century by the computer manipulation of spatial arrays of terrain heights, or digital elevation models (DEMs), which can quantify and portray ground-surface form over large areas (Maune, 2001). Morphometric procedures are implemented routinely by commercial geographic information systems (GIS) as well as specialized software (Harvey and Eash, 1996; Köthe and others, 1996; ESRI, 1997; Drzewiecki et al., 1999; Dikau and Saurer, 1999; Djokic and Maidment, 2000; Wilson and Gallant, 2000; Breuer, 2001; Guth, 2001; Eastman, 2002). The new Earth Surface edition of the Journal of Geophysical Research, specializing in surficial processes, is the latest of many publication venues for terrain modeling. This is the fourth update of a bibliography and introduction to terrain modeling (Pike, 1993, 1995, 1996, 1999) designed to collect the diverse, scattered literature on surface measurement as a resource for the research community. The use of DEMs in science and technology continues to accelerate and diversify (Pike, 2000a). New work appears so frequently that a sampling must suffice to represent the vast literature. This report adds 1636 entries to the 4374 in the four earlier publications1. Forty-eight additional entries correct dead Internet links and other errors found in the prior listings. Chronicling the history of terrain modeling, many entries in this report predate the 1999 supplement. Coverage is representative from about 1800 through early–mid 2002. Papers increasingly are published exclusively or in duplicate on the Internet's World Wide Web; the dates given here for Web addresses (URLs) that lack a print publication indicate a Web site's last update or my last access of it. The bibliography is arranged alphabetically and thus is not readily summarized. This introduction cites about 500 entries, a third of them grouped under 24 morphometric topics, as a guide to the listing's contents. Continuing the practice of previous bibliographies in the series to provide more information on a few applications (see summary of past topics in Pike, 2000a), this report elaborates further on topographic data, putative new parameters, tectonic geomorphology/neo-orometry, biogeography, ice-cap morphometry, results from the Mars Global DEM, landslide-hazard mapping, terrain modeling as physics, Hack's law, and broad-scale computer visualization. The literature of some of these subjects is large, and none of the summaries is intended to more than introduce the topic and comment on some of the current contributions of terrain modeling. Closing the essay is a discussion of pre-1900 papers that trace the evolution of ridge-line and watercourse quantification by descriptive geometry, as well as comments on some new books and an on-line bulletin board.

Open-File Report↗
USGS2014

Bathymetry and acoustic backscatter: outer mainland shelf and slope, Gulf of Santa Catalina, southern California

In 2010 and 2011, scientists from the U.S. Geological Survey (USGS), Coastal and Marine Geology Program, acquired bathymetry and acoustic-backscatter data from the outer shelf and slope region offshore of southern California. The surveys were conducted as part of the USGS Marine Geohazards Program. Assessment of the hazards posed by offshore faults, submarine landslides, and tsunamis are facilitated by accurate and detailed bathymetric data. The surveys were conducted using the USGS R/V Parke Snavely outfitted with a 100-kHz Reson 7111 multibeam-echosounder system. This report provides the bathymetry and backscatter data acquired during these surveys in several formats, a summary of the mapping mission, maps of bathymetry and backscatter, and Federal Geographic Data Committee (FGDC) metadata.

California↗
USGS2014

Chirp seismic-reflection data from the Baltimore, Washington, and Norfolk Canyons, U.S. mid-Atlantic margin

A large number of high-resolution geophysical surveys between Cape Hatteras and Georges Bank have been conducted by federal, state, and academic institutions since the turn of the century. A major goal of these surveys is providing a continuous view of bathymetry and shallow stratigraphy at the shelf edge in order to assess levels of geological activity during the current sea level highstand. In 2012, chirp seismic-reflection data was collected by the U.S. Geologial Survey aboard the motor vessel Tiki XIV near three United States mid-Atlantic margin submarine canyons. These data can be used to further our understanding of passive continental margin processes during the Holocene, as well as providing valuable information regarding potential submarine geohazards.

Mid-atlantic Margin↗
USGS1982

Gulf of Alaska and Lower Cook Inlet summary report 3: Second revision of Outer Continental Shelf oil and gas activities in the Gulf of Alaska (including Lower Cook Inlet) and their onshore impacts: A summary report, September 1980

Five Outer Continental Shelf (OCS) lease sales have been held in the Gulf of Alaska subregion of Alaska. Lease Sale 39, in the northern Gulf of Alaska, was held on April 13, 1976, and it resulted in the leasing of 76 tracts. Lease Sale CI, held on October 27, 1977, resulted in the leasing of 87 tracts in Lower Cook Inlet. Lease Sale 55 in the eastern Gulf of Alaska, held on October 21, 1980, leased 35 tracts. The first Reoffering Sale (RS-1), held on June 30, 1981, resulted in the leasing of one tract in the eastern Gulf of Alaska. Lease Sale 60, the most recent sale in the subregion, was held on September 29, 1981. It resulted in the leasing of 13 tracts in the Lower Cook Inlet and the Shelikof Strait. Exploratory drilling has been conducted on tracts leased in Lease Sales 39 and CI. No commercial discoveries were made, and no further exploratory drilling is anticipated on tracts leased in either sale. ARCO has plans to explore a tract leased in Lease Sale 55 in January 1983. Chevron has conducted geohazard studies on tracts leased in Lease Sale 60. The results of these studies will determine if exploratory wells will be drilled. Exploratory drilling, if it does take place, is not anticipated before the summer of 1983. In March 1982, the Department of the Interior prepared new resource estimates for the Gulf of Alaska subregion. The risked mean resource estimates for tracts leased in Lease Sale 55 and Lease Sale RS-1 are 12.1 million barrels of oil and 46.2 billion cubic feet of gas. The risked mean resource estimates for tracts leased in Lease Sale 60 are 5.6 million barrels of oil and 5 billion cubic feet of gas. The onshore impacts from previous OCS exploration in the Gulf of Alaska and the Lower Cook Inlet were minimal. Yakutat will be used to support exploratory drilling on any Lease Sale 55 or Lease Sale RS-1 tracts. If exploratory drilling takes place on Lease Sale 60 tracts, support facilities are expected to be located in Kenai or on Kodiak Island.

Gulf of Alaska, Outer Continental Shelf↗
USGS2015

Geologic map of the southern White Ledge Peak and Matilija quadrangles, Santa Barbara and Ventura Counties, California

This report presents a digital geologic strip map of the southern parts of the contiguous White Ledge Peak and Matilija 7.5’ quadrangles in coastal southern California. With a compilation scale of 1:24,000 (one inch on the map to 2,000 feet on the ground), the map depicts the distribution of bedrock units, surficial deposits, and associated deformation adjacent to and south of the Arroyo Parida fault and in the southern Ojai Valley east of the Ventura River. This new compilation, combined with a recently published geologic map of the Santa Barbara coastal plain (U.S. Geological Survey Scientific Investigations Map 3001), completes a 69-km-long east-west mapping transect from Goleta to Ojai by the U.S. Geological Survey. These two contiguous geologic maps provide new insights and constraints on Neogene-through-Quaternary tectonic deformation and consequent landscape change, including geohazards in the urbanized southern flank of the Santa Ynez Mountains. A principal aim of the new mapping and associated fault-kinematic measurements is to document and constrain the nature of transpressional strain transfer between various regional, potentially seismogenic faults. In the accompanying pamphlet, surficial and bedrock map units are described in detail as well as a summary of the structural and fault-kinematic framework of the map area. New biostratigraphic and biochronologic data based on microfossil identifications are presented in expanded unit descriptions of the marine Neogene Monterey and Sisquoc Formations. Site-specific fault kinematic observations are embedded in the digital map database. This compilation provides a uniform geologic digital geodatabase and map plot files that can be used for visualization, analysis, and interpretation of the area’s geology, geologic hazards, and natural resources.

California↗
USGS1999

Apparatus investigates geological aspects of gas hydrates

The US Geological Survey (USGS), in response to potential geohazards, energy resource potential, and climate issues associated with marine gas hydrates, has developed a laboratory research system that permits hydrate genesis and dissociation under deep-sea conditions, employing user-selected sediment types and pore fluids. The apparatus, GHASTI (gas hydrate and sediment test laboratory instrument), provides a means to link field studies and theory and serves as a tool to improve gas hydrate recognition and assessment, using remote sensing techniques. GHASTLI's use was proven in an exploration well project led by the Geological Survey of Canada and the Japanese National Oil Corp., collaborating with Japan Petroleum Exploration Co. and the USGS. The site was in the Mackenzie Delta region of the Northwest Territories (Mallik 2L-38 drillsite). From tests on natural methane hydrate-bearing sand recovered at about 1,000 m subsurface, the in situ quantity of hydrate was estimated from acoustic properties, and a substantial increase in shear strength due to the presence of the hydrate was measured. 1 2 GHASTI can mimic a wide range of geologic settings and processes. Initial goals involve improved recognition and mapping of gas hydrate-bearing sediments, understanding factors that control the occurrence and concentration of gas hydrates, knowledge of hydrate's significance to slope failure and foundation problems, and analysis of gas hydrate's potential use as an energy resource.

Oil & Gas Journal↗
USGS2001

Global occurrences of gas hydrate

Natural gas hydrate is found worldwide in sediments of outer continental margins of all oceans and in polar areas with continuous permafrost. There are currently 77 localities identified globally where geophysical, geochemical and/or geological evidence indicates the presence of gas hydrate. Details concerning individual gas-hydrate occurrences are compiled at a new world-wide-web (www) site (http://walrus.wr.usgs.gov/globalhydrate). This site has been created to facilitate global gas-hydrate research by providing information on each of the localities where there is evidence for gas hydrate. Also considered are the implications of gas hydrate as a potential (1) energy resource, (2) factor in global climate change, and (3) geohazard.

Conference Paper↗
USGS2009

International year of planet earth 7. Oceans, submarine land-slides and consequent tsunamis in Canada

Canada has the longest coastline and largest continental margin of any nation in the World. As a result, it is more likely than other nations to experience marine geohazards such as submarine landslides and consequent tsunamis. Coastal landslides represent a specific threat because of their possible proximity to societal infrastructure and high tsunami potential; they occur without warning and with little time lag between failure and tsunami impact. Continental margin landslides are common in the geologic record but rare on human timescales. Some ancient submarine landslides are massive but more recent events indicate that even relatively small slides on continental margins can generate devastating tsunamis. Tsunami impact can occur hundreds of km away from the source event, and with less than 2 hours warning. Identification of high-potential submarine landslide regions, combined with an understanding of landslide and tsunami processes and sophisticated tsunami propagation models, are required to identify areas at high risk of impact.

Geoscience Canada↗