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

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At least 973 records · Page 54Linked to original sources

USGS1983

Proceedings of Workshop XIV: earthquake hazards of the Puget Sound region, Washington

This conference, the fourteenth in a series sponsored by the Earthquake Hazards Reduction Program, was held October 13-15, 1980 at Lake Wilderness, Washington. The stated purpose of the conference was to assess progress and the state of knowledge of earthquake hazards in the Puget Sound region of Washington. The small size of the group and the pleasant informal setting of the Lake Wilderness Conference Facility created conditions which encouraged abundant discussion, expansion of ideas and impromptu presentation that went well beyond the scheduled topics, most of which are covered in this volume.

Washington↗

USGS2010

Global mineral resource assessment

Introduction In response to the growing demand for information on the global mineral-resource base, the U.S. Geological Survey (USGS) is conducting the Quantitative Global Mineral Resource Assessment Project (GMRAP), a cooperative international project, begun in 2002, to assess the world's undiscovered nonfuel mineral resources. Primary Objectives The USGS conducts national and global assessments of resources (mineral, energy, water, biologic) to provide science in support of decisionmaking. Mineral resource assessments provide a synthesis of available information about where mineral deposits are known and suspected in the Earth’s crust, what commodities may be present, and estimates of amounts of resources that may be present in undiscovered deposits. The Global Mineral Resource Assessment Project started in 2002 as a cooperative international effort to assess the world’s undiscovered nonfuel mineral resources. Primary objectives are to: Outline the regional locations and estimate the probable amounts of the world’s undiscovered resources of copper, platinum-group elements (PGE), and potash in selected types of mineral deposits to depths of 1 to 3 kilometers below the Earth’s surface. Provide the first globally consistent and comprehensive analysis of undiscovered nonfuel mineral resources to provide all nations with a regional and global context for evaluating their mineral resources, planning for new mineral exploration and anticipating the economic, environmental, and social impacts of mineral development, and making land use decisions. The project emphasizes the most important types of mineral deposits for world supply of copper, platinum-group elements (PGE) and nickel, and potash. Go to the Quantitative Global Mineral-Resource Assessments home page for more information.

Scientific Investigations Report↗

USGS2024

Seismic techniques and suggested instrumentation to monitor volcanoes

Introduction Changes in the pressure or location of magma can stress or break surrounding rocks and trigger flow of nearby waters and gases, causing seismic signals, such as discrete earthquakes and tremor. These phenomena are types of seismic unrest that commonly precede eruption and can be used to forecast volcanic activity. Mass movements at the surface, including avalanches, debris flows, and lahars, may also generate seismic signals that are specifically addressed in chapter H , this volume (Thelen and others, 2024). Our focus in this chapter is to determine the levels of instrumentation recommended to produce high-quality, well-constrained seismic observations important for early warning of impending eruptions, detecting changes in ongoing eruptions, and characterizing other hazardous volcanic events. There are emerging techniques and new types of instrumentation, such as distributed acoustic sensing or rotational seismometers, that we do not consider here. These types of instrumentation show promise for monitoring but still require maturation before being considered more generally in volcano monitoring. Most of the capabilities mentioned below are universal for all types of volcanic systems, although some are best applied to stratovolcanoes with an apical single vent. In some settings, such as calderas or shield volcanoes, we must broaden coverage to include multiple possible storage regions or vent locations. As an example, Thelen (2014) discretized the long rift zones of shield volcanoes in Hawaiʻi as a set of evenly spaced “vents.” In this construct, each vent comes with recommendations, and several thousand network configurations were simulated to assess the effect on network quality levels and to determine the most efficient network design. The same process could be applied in a caldera setting or a volcanic field, where an evenly spaced grid of potential vents is considered. Localized recommendations for each unique system are beyond the scope of this report and left up to local experts to assess based on the conditions, restrictions, and requirements of each volcano.

Scientific Investigations Report↗

USGS2025

Constraining landslide frequency across the United States to inform county-level risk reduction

Informative landslide hazard estimates are needed to support landslide mitigation strategies to reduce landslide risk across the United States. Whereas existing national-scale landslide susceptibility products assess where landslides are likely to occur, they do not address how often , which is a critical element of landslide hazard and risk assessments. In particular, the U.S. Federal Emergency Management Agency's National Risk Index (NRI) requires landslide frequency estimates to inform expected annual loss estimates. We present county-level landslide frequency (landslides per area per year) estimates for the 50 US states. We applied Bayesian negative binomial regression to estimate both the expected (average) reported landslide frequency and full distribution of annual landslide counts for each county. We compared a suite of models that used combinations of landslide-susceptible area, probability of potentially triggering earthquakes, frequency of potentially triggering precipitation, and ecological region as predictors. We trained our models with landslide inventory data from counties with the most comprehensive records available nationwide and used zero-inflated negative binomial distributions as an incompleteness model to correct for temporal reporting gaps. We selected a preferred frequency model to inform the NRI based on information criteria and physically plausible parameter estimates. The model showed that average annual reported landslide frequencies vary by 5 orders of magnitude across US counties, ranging from 0.002 (0.00015–0.05) landslides 1000 km −2 yr −1 in Kusilvak Census Area, Alaska, to 29 (19–46) landslides 1000 km −2 yr −1 in Lake County, California, reflecting the country's strong variations in landslide susceptibility, earthquake probability, and other factors for which ecological region serves as a proxy. Counties with estimated frequencies in the top 20 % of all counties are predominately along the West Coast of the continental United States, in mountainous regions of the Pacific Northwest and Intermountain West, in locally steep or earthquake-prone regions of the Midwest and Southeast, along the Appalachians, in southern and southeastern Alaska, and on some Hawaiian islands. By examining the number of landslides predicted in 99th percentile years for each county, we identified that 26 % of US counties likely have potential for widespread landsliding with more than 10 landslides 1000 km −2 yr −1 , even when such large events have not been reported in the training data for that county. Overall, our results better represent the range of possible landslide frequencies and spatial variations than previous national-scale estimates reported in the NRI, and our approach can inform other risk-reduction and loss-mitigation efforts across the United States and globally.

Natural Hazards and Earth System Sciences↗

USGS2004

A preliminary assessment of geologic framework and sediment thickness studies relevant to prospective US submission on extended continental shelf

Under the provisions of Articles 76 and 77 of the United Nations Convention on the Law of the Sea (UNCLOS), coastal States have sovereign rights over the continental shelf territory beyond 200-nautical mile (nm) from the baseline from which the territorial sea is measured if certain conditions are met regarding the geologic and physiographic character of the legal continental shelf as defined in those articles. These claims to an extended continental shelf must be supported by relevant bathymetric, geophysical and geological data according to guidelines established by the Commission on the Limits of the Continental Shelf (CLCS, 1999). In anticipation of the United States becoming party to UNCLOS, Congress in 2001 directed the Joint Hydrographic Center/Center for Coastal and Ocean Mapping at the University of New Hampshire to conduct a study to evaluate data relevant to establishing the outer limit of the juridical continental shelf beyond 200 nm and to recommend what additional data might be needed to substantiate such an outer limit (Mayer and others, 2002). The resulting report produced an impressive and sophisticated GIS database of data sources. Because of the short time allowed to complete the report, all seismic reflection data were classified together; the authors therefore recommended that USGS perform additional analysis on seismic and related data holdings. The results of this additional analysis are the substance of this report, including the status of geologic framework, sediment isopach research, and resource potential in the eight regions1 identified by Mayer and others (2002) where analysis of seismic data might be crucial for establishing an outer limit . Seismic reflection and refraction data are essential in determining sediment thickness, one of the criteria used in establishing the outer limits of the juridical continental shelf. Accordingly, the initial task has been to inventory public-domain seismic data sources, primarily those regionally extensive data held within the Department of the Interior (DOI). The numerous seismic reflection and refraction surveys collected prior to 1970 by academic and governmental institutions are generally not included in this compilation, except where they provide unique data in a region. These data sources were omitted from this report because they were deemed to be of insufficient quality (poorly navigated or low resolution) to meet the CLCS standards for a submission, or they were redundant with higher-quality, more modern data. Hence, this report attempts to identify those data sets of highest utility for establishing the outer limits of the juridical continental shelf. If there was any ambiguity or uncertainty about the relevance of a data set to a continental shelf submission, either by its quality, location, or other parameter, it was included in this compilation. This report does not summarize other geophysical data (such as marine magnetics or gravity) that might be relevant to understanding crustal provenance and geological continuity. Detailed metadata tables and maps are included to facilitate the location and utilization of these sources when a comprehensive assessment (?desktop study?) is undertaken.

Open-File Report↗

USGS2026

Strategic approach for bird restoration evaluation - FY 2025 annual report

The Deepwater Horizon oil spill (hereafter “ spill ”) resulted in an estimated loss of 56,141–102,399 birds across 93 species along the U.S. Gulf of America coast. Injured species included those that nest locally along the northern Gulf of America coast as well as species that nest hundreds or thousands of kilometers outside of the region. The breadth of injury and the expansive geographic distribution of birds affected by the spill necessitated implementation of numerous and diverse projects designed to restore the injury of all affected bird species. As of September 2025, the Trustees, who are authorized to act on behalf of the public to restore injuries caused by the spill , have approved 39 projects, amounting to >60% of the total funds specifically allocated for bird restoration (i.e., Bird Restoration Type funding). Strategic allocation of remaining Bird Restoration Type funding is necessary to ensure that restoration of all injured bird species is achieved. An essential component of planning for future restoration is understanding the progress made from restoration actions conducted to date. The purpose of this project is to develop a plan that assesses the current restoration progress for each of the 93 injured species based on available data. The restoration assessment plan will be derived from a data gap analysis that identifies species for which data may be insufficient to assess restoration progress. This project will also allow Trustees to review and update the indicators of restoration success developed for injured bird species (e.g., population counts, reproduction metrics) that are used to evaluate restoration progress.

Annual Report↗

USGS2021

Down to Earth with nuclear electromagnetic pulse: Realistic surface impedance aﬀects mapping of the E3 geoelectric hazard

An analysis is made of Earth-surface geoelectric fields and voltages on electricity transmission power-grids induced by a late-phase E3 nuclear electromagnetic pulse (EMP). A hypothetical scenario is considered of an explosion of several hundred kilotons set several hundred kilometers above the eastern-midcontinental United States. Ground-level E3 geoelectric fields are estimated by convolving a standard parameterization of E3 geomagnetic field variation with magnetotelluric Earth-surface impedance tensors derived from wideband measurements acquired across the study region during a recent survey. These impedance tensors are a function of subsurface three-dimensional electrical conductivity structure. Results, presented as a movie-map, demonstrate that localized differences in surface impedance strongly distort the amplitude, polarization, and variational phase of induced E3 geoelectric fields. Locations with a high degree of E3 geoelectric polarization tend to have high geoelectric amplitude. Uniform half-space models and one-dimensional, depth-dependent models of Earth-surface impedance, such as those widely used in government and industry reports informing power-grid vulnerability assessment projects, do not provide accurate estimates of the E3 geoelectric hazard in complex geological settings. In particular, for the Eastern-Midcontinent, half-space models can lead to (order-one) overestimates/underestimates of EMP-induced geovoltages on parts of the power grid by as much as 1,000 volts (a range of 2,000 volts)—comparable to the amplitudes of the geovoltages themselves.

Earth and Space Sciences↗

USGS2017

Global and regional sea level rise scenarios for the United States

The Sea Level Rise and Coastal Flood Hazard Scenarios and Tools Interagency Task Force, jointly convened by the U.S. Global Change Research Program (USGCRP) and the National Ocean Council (NOC), began its work in August 2015. The Task Force has focused its efforts on three primary tasks: 1) updating scenarios of global mean sea level (GMSL) rise, 2) integrating the global scenarios with regional factors contributing to sea level change for the entire U.S. coastline, and 3) incorporating these regionally appropriate scenarios within coastal risk management tools and capabilities deployed by individual agencies in support of the needs of specific stakeholder groups and user communities. This technical report focuses on the first two of these tasks and reports on the production of gridded relative sea level (RSL, which includes both ocean-level change and vertical land motion) projections for the United States associated with an updated set of GMSL scenarios. In addition to supporting the longer-term Task Force effort, this new product will be an important input into the USGCRP Sustained Assessment process and upcoming Fourth National Climate Assessment (NCA4) due in 2018. This report also serves as a keytechnical input into the in-progress USGCRP Climate Science Special Report (CSSR).

Report↗

USGS1974

Hydrologic Unit Map -- 1974, Idaho

This map and accompanying table show Hydrologic Units that are basically hydrographic in nature. The Cataloging Units shown will supplant the Cataloging Units previously used by the U.S. Geological Survey in its Catalog of Information on Water Data (1966-72). The previous U.S. Geological Survey Catalog-Indexing System was by map number and letter, such as 49M. The boundaries as shown have been adapted from "The Catalog of Information on Water Data" (1972), "Water Resources Regions and Subregions for the National Assessment of Water and Related Land Resources" by the U.S. Water Resources Council (1970), "River Basins of the United States" by the U.S. Soil Conservation Service (1963, 1970), "River Basin Maps Showing Hydrologic Stations" by the Inter-Agency Committee on Water Resources, Subcommittee on Hydrology (1961), and State planning maps.

Idaho↗

USGS1974

Hydrologic Unit Map -- 1974, State of Michigan

This map and accompanying table show Hydrologic Units that are basically hydrographic in nature. The Cataloging Units shown will supplant the Cataloging Units previously used by the U.S. Geological Survey in its Catalog of Information on Water Data (1966-72). The previous U.S. Geological Survey Catalog-Indexing System was by map number and letter, such as 49 M. The boundaries shown have been adapted from "The Catalog of Information on Water Data" (1972), "Water Resources Regions and Subregions for the National Assessment of Water and Related Land Resources" by the U.S. Water Resources Council (1970), " River Basins of the United States" by the U.S. Soil Conservation Service (1963, 1970), "River Basin Maps Showing Hydrologic Stations" by the Inter-Agency Committee on Water Resources, Subcommittee on Hydrology (1961), and States planning maps.

Michigan↗

USGS1976

Hydrologic Unit Map - 1974, state of Montana

This map and accompanying table show Hydrologic Units that are basically hydrographic in nature. The Cataloging Units shown will supplant the Cataloging Units previously used by the U.S. Geological Survey in its Catalog of Informaiton on Water Data (1966-72). The previous U.S. Geological Survey Catalog-Indexing System was by map number and letter, such as 49M. The boundaries as shown have been adapted from "The Catalog of Information on Water Data" (1972), "Water Resources Regions and Subregions for the National Assessment of Water and Related Land Resources" by the U.S. Water Reseources Council (1970), "River Basins of the United States" by the U.S. Soil Conservation Service ((1963, 1970), "River Basin Maps Showing Hydrologic Stations" by the Inter-Agency Committee on Water Resources, Subcommittee on Hydrology (1961), and State planning maps.

Montana↗

USGS1974

Hydrologic Unit Map -- 1974, New York

This map and accompanying table show Hydrologic Units that are basically hydrographic in nature. The Cataloging Units shown will supplant the Cataloging Units previously used by the U.S. Geological Survey in its Catalog of Information on Water Data (1966-72). The previous U.S. Geological Survey Catalog-Indexing System was by map number and letter, such as 49M. The boundaries shown have been adapted from "The Catalog of Information on Water Data" (1972), "Water Resources Regions and Subregions for the National Assessment of Water and Related Land Resources" by the U.S. Water Resources Council (1970), " River Basins of the United States" by the U.S. Soil Conservation Service (1963, 1970), "River Basin Maps Showing Hydrologic Stations" by the Inter-Agency Committee on Water Resources, Subcommittee on Hydrology (1961), and States planning maps.

New York↗

USGS1974

Hydrologic unit map:1974, State of Utah

This map and accompanying table show Hydrologic Units that are basically hydrographic in nature. The Cataloging Units shown will supplant the Cataloging Units previously used by the U.S. Geological Survey in its Catalog of Information on Water Data (1966-72). The previous U.S. Geological Survey Catalog-Indexing System was by map number and letter, such as 49M. the boundaries as shown have been adapted from “the Catalog of Information on Water Data” (1972), “Water Resources Regions and Subregions for the National Assessment of Water and Related Land Resources” by the U.S. Water Resources Council (1970), “River Basins of the United States” by the U.S. Soil Conservation Service (1963, 1970), “River Basin Maps Showing Hydrologic Stations” by the Inter-Agency Committee on Water Resourres, Subcommittee on hydrology (1961), and State planning maps.

Utah↗

USGS2000

Interagency field manual for the collection of water-quality data

The Interagency Field Manual for the Collection of Water-Quality Data was initiated by the U.S. Environmental Protection Agency (USEPA), Region VI, to compile field water-sample-collection methods (water column only) commonly used by various "participating" agencies for assessing the water quality of international and transboundary rivers. These agencies include the USEPA-Regions VI and IX, International Boundary and Water Commission (IBWC), U.S. Geological Survey (USGS), Bureau of Reclamation (BOR), and State regulatory agencies. The manual is intended to provide an objective assessment of the benefits and limitations associated with each sampling method to enable the collector to select the field procedure that is most appropriate for the respective agency’s needs or individual project’s data quality objectives (DQO).

Open-File Report↗

USGS2013

A manual for remote sensing of Maine lake clarity

The purpose of this manual is to support use of satellite-based remote sensing for statewide lake water-quality monitoring in Maine. The authors describe step-by-step methods that combine Landsat and MODIS satellite data with field-collected Secchi disk data for statewide assessment of lake water clarity. Landsat can be simultaneously used to assess more than Maine 1,000 lakes ≥ 8 ha, whereas MODIS can be used to assess a maximum of 364 lakes ≥ 100 ha (250-m image resolution) or 83 lakes ≥ 400 ha (500-m image resolution). Although the methods were specifically developed for Maine, other states or non-Maine agencies may find these methods as useful starting points in developing their own protocols for regional remote lake monitoring.

Maine↗

USGS2008

National parks: Chapter 4

Covering about 4% of the United States, the 338,000 km² of protected areas in the National Park System contain representative landscapes of all of the nation’s biomes and ecosystems. The U.S. National Park Service Organic Act established the National Park System in 1916 “to conserve the scenery and the natural and historic objects and the wild life therein and to provide for the enjoyment of the same in such manner and by such means as will leave them unimpaired for the enjoyment of future generations.”1 Approximately 270 national park system areas contain significant natural resources. Current National Park Service policy for natural resource parks calls for management to preserve fundamental physical and biological processes, as well as individual species, features, and plant and animal communities. Parks with managed natural resources range from large intact (or nearly intact) ecosystems with a full complement of native species— including top predators—to those diminished by disturbances such as within-park or surrounding-area legacies of land use, invasive species, pollution, or regional manipulation of resources. The significance of national parks as representatives of naturally functioning ecosystems and as refugia for natural processes and biodiversity increases as surrounding landscapes become increasingly altered by human activities.

Synthesis and Assessment Product↗

USGS2006

Vascular Plant and Vertebrate Inventory of Saguaro National Park, Rincon Mountain District

Executive Summary This report summarizes the results of the first comprehensive inventory of plants and vertebrates at the Rincon Mountain District (RMD) of Saguaro National Park, Arizona. From 2001 to 2003 we surveyed for vascular plants and vertebrates (amphibians, reptiles, birds, and mammals) at the district to document the presence of species within its boundaries. Park staff also surveyed for medium and large mammals using infrared-triggered cameras from 1999 to 2005. This report summarizes the methods and results of these two efforts. Our spatial sampling design was ambitious and was one of the first of its kind in the region to colocate study sites for vegetation and vertebrates using a stratified random design. We also chose the location of some study sites non-randomly in areas that we thought would have the highest species richness. Because we used repeatable study designs and standardized field methods, these inventories can serve as the first step in a biological monitoring program for the district. We also provide an important overview of most previous survey efforts in the district. We use data from our inventory and other surveys to compile species lists and to assess inventory completeness. With the exception of plants, our survey effort was the most comprehensive ever undertaken in the district. We recorded a total of 801 plant and vertebrate species, including 50 species not previously found in the district (Table 1) of which five (all plants) are non-native species. Based on a review of our inventory and past research at the district, there have been a total of 1,479 species of plants and vertebrates found there. We believe inventories for all taxonomic groups are nearly complete. In particular, the plant, amphibian and reptile, and mammal species lists are the most complete of any comparably large natural area of the 'sky island' region of southern Arizona and adjacent Mexico. For each taxon-specific chapter we discuss patterns of species richness and environmental determinants of these patterns. For all groups except medium and large mammals, the low elevation stratum (<4,000 feet) contained the highest species richness, after accounting for differences in survey effort among strata. This is consistent with known patterns of species richness in the sky island mountain ranges. Using data on relative abundance for plants and birds, we were able to identify a number of distinct ecological communities, which were consistent with known patterns in the sky islands. Our review of species lists and park records reveals that the district has lost species, particularly plants and mammals, in the past few decades. Because of the district's close proximity to the rapidly growing city of Tucson, there are a number of development-related threats that could cause additional species loss or decline in abundance of some species. In particular, the increasing groundwater pumping near Rincon Creek, the most species-rich area in the park, is likely to impact the unique riparian vegetation and animals of that area. We discuss this and other demands on the ecological integrity of the district. We also recommend additional inventory, monitoring, and research studies.

Open-File Report↗

USGS2008

Empirical models to predict the volumes of debris flows generated by recently burned basins in the western U.S.

Recently burned basins frequently produce debris flows in response to moderate-to-severe rainfall. Post-fire hazard assessments of debris flows are most useful when they predict the volume of material that may flow out of a burned basin. This study develops a set of empirically-based models that predict potential volumes of wildfire-related debris flows in different regions and geologic settings. The models were developed using data from 53 recently burned basins in Colorado, Utah and California. The volumes of debris flows in these basins were determined by either measuring the volume of material eroded from the channels, or by estimating the amount of material removed from debris retention basins. For each basin, independent variables thought to affect the volume of the debris flow were determined. These variables include measures of basin morphology, basin areas burned at different severities, soil material properties, rock type, and rainfall amounts and intensities for storms triggering debris flows. Using these data, multiple regression analyses were used to create separate predictive models for volumes of debris flows generated by burned basins in six separate regions or settings, including the western U.S., southern California, the Rocky Mountain region, and basins underlain by sedimentary, metamorphic and granitic rocks. An evaluation of these models indicated that the best model (the Western U.S. model) explains 83% of the variability in the volumes of the debris flows, and includes variables that describe the basin area with slopes greater than or equal to 30%, the basin area burned at moderate and high severity, and total storm rainfall. This model was independently validated by comparing volumes of debris flows reported in the literature, to volumes estimated using the model. Eighty-seven percent of the reported volumes were within two residual standard errors of the volumes predicted using the model. This model is an improvement over previous models in that it includes a measure of burn severity and an estimate of modeling errors. The application of this model, in conjunction with models for the probability of debris flows, will enable more complete and rapid assessments of debris flow hazards following wildfire.

Geomorphology↗