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The U.S. Geological Survey (USGS) operated 11,850 continuous surface-water monitoring locations (streamgages) across the United States in 2023. The streamgages provide information on river height and streamflow, typically at 15-minute intervals. This information is then made available to everyone, most of it delivered nearly in realtime on the USGS National Water Dashboard.
Public service is about making a difference. As the Federal government's principal natural science and information agency, the USGS is committed to providing excellence in public service and to making a difference to the world we live in. Our motto conveys an enduring message: science for a changing world . The changing nature of the natural and physical world is the primary driving force and motivation behind all of the work USGS does in biology, geology, mapping, and water. We live our motto each day in fulfilling our mission to provide reliable, impartial information to the citizen of this country and to the global community.
Photographs and other images of the Earth taken from the air and from space show a great deal about the planet's landforms, vegetation, and resources. Aerial and satellite images, known as remotely sensed images, permit accurate mapping of land cover and make landscape features understandable on regional, continental, and even global scales. Transient phenomena, such as seasonal vegetation vigor and contaminant discharges, can be studied by comparing images acquired at different times. The U.S. Geological Survey (USGS), which began using aerial photographs for mapping in the 1930's, archives photographs from its mapping projects and from those of some other Federal agencies. In addition, many images from such space programs as Landsat, begun in 1972, are held by the USGS. Most satellite scenes can be obtained only in digital form for use in computer-based image processing and geographic information systems, but in some cases are also available as photographic products.
The information in this booklet was compiled to answer inquiries received by the Geological Survey from students, teachers, writers, editors, publishers of encyclopedias, almanacs and other reference books, and people in many other fields of work. The elevations of features and distances between points in the United States were determined from surveys and topographic maps of the Geological Survey or obtained from other sources. Some of this information, compiled from older maps, will be revised as new surveys are completed. For further information, write to the U. S. Geological Survey, 507 National Center.Reston,Virginia 22092.
The information in this booklet was compiled to answer inquiries received by the U.S. Geological Survey from students; teachers; writers; editors; publishers of encyclopedias, almanacs, and other reference books; and people in many other fields of work. The elevations of features and distances between points in the United States were determined from surveys and topographic maps of the U.S. Geological Survey or obtained from other sources. In most cases, the elevations were determined from surveys and from 1:24,000- and 1:25,000-scale, 7.5-minute topographic quadrangle maps. In Alaska, information was taken from 1:63,360-scale, 15-minute topographic quadrangle maps. In a few cases, data were obtained from older, 1:62,500-scale, 15-minute maps; these maps are being replaced with larger-scale 7.5-minute coverage. Further information about U.S. Geological Survey products can be obtained from: U.S. Geological Survey, Earth Science Information Center, 507 National Center, Reston, VA 22092 or phone 703-860-6045.
The U.S. Geological Survey (USGS) is using research and data from the Mekong River Delta in Southeast Asia to compare restoration, conservation, and management efforts there with those done in other major river deltas, such as the Mississippi River Delta in the United States. The project provides a forum to engage regional partners in the Mekong Basin countries to share data and support local research efforts. Ultimately, Forecast Mekong will lead to more informed decisions about how to make the Mekong and Mississippi Deltas resilient in the face of climate change, economic stresses, and other impacts.
The Equus Beds aquifer in south-central Kansas is a primary water source for the city of Wichita. The Equus Beds aquifer storage and recovery (ASR) project was developed to help the city of Wichita meet increasing current and future demands. The Equus Beds ASR project is a recent part of an 80-year cooperative water science effort with the city of Wichita. The U.S. Geological Survey (USGS) Kansas Water Science Center characterizes river and aquifer water-quality and quantity and evaluates changes that may or may not be related to ASR. The USGS data are used by the city of Wichita to make informed management decisions, satisfy regulatory requirements, and serve as a baseline to detect any subsequent changes that may be related to ASR.
The National Cartographic Information Center (NCIC) exists to help you find maps of all kinds and much of the data and materials used to compile and to print them. NCIC collects, sorts and describes all types of cartographic information from Federal, State and local government agencies and, where possible, from private companies in the mapping business. It is the public's primary source for cartographic information. (See partial list of Federal agencies and their map and other cartographic products.)
The U.S. Geological Survey (USGS) operated 12,165 continuous surface-water monitoring locations (streamgages) across the United States in 2024. The streamgages provide information on river height and streamflow, typically at 15-minute intervals. This information is then made available to everyone, most of it delivered nearly in realtime on the USGS National Water Dashboard.
Ground-based gravitational wave interferometers such as the Laser Interferometer Gravitational-wave Observatory (LIGO) are susceptible to ground shaking from high-magnitude teleseismic events, which can interrupt their operation in science mode and significantly reduce their duty cycle. It can take several hours for a detector to stabilize enough to return to its nominal state for scientific observations. The down time can be reduced if advance warning of impending shaking is received and the impact is suppressed in the isolation system with the goal of maintaining stable operation even at the expense of increased instrumental noise. Here, we describe an early warning system for modern gravitational-wave observatories. The system relies on near real-time earthquake alerts provided by the U.S. Geological Survey (USGS) and the National Oceanic and Atmospheric Administration (NOAA). Preliminary low latency hypocenter and magnitude information is generally available in 5 to 20 min of a significant earthquake depending on its magnitude and location. The alerts are used to estimate arrival times and ground velocities at the gravitational-wave detectors. In general, 90% of the predictions for ground-motion amplitude are within a factor of 5 of measured values. The error in both arrival time and ground-motion prediction introduced by using preliminary, rather than final, hypocenter and magnitude information is minimal. By using a machine learning algorithm, we develop a prediction model that calculates the probability that a given earthquake will prevent a detector from taking data. Our initial results indicate that by using detector control configuration changes, we could prevent interruption of operation from 40 to 100 earthquake events in a 6-month time-period.
Tribal nations and Indigenous communities are key collaborators on adaptation work within the Climate Adaptation Science Center (CASC) network. The centers have partnered with numerous Tribal and Indigenous communities on projects or activities to better understand the communities’ specific knowledge of and exposure to impacts of climate change, to increase or assist with capacity to support adaptation planning, and to identify and address climate science needs. Projects and activities generated in the various CASC regions have different Tribal and Indigenous stakeholders, climate change contexts, and training needs. Consequently, these projects and activities were neither implemented nor reported consistently throughout the network. Information and materials on the various projects and activities were gathered and are presented in the Tribal and Indigenous Projects Data Sheet (hereafter, Data Sheet) with the goals of reducing inconsistencies between CASCs and benefitting other agencies who plan to implement similar activities. The Data Sheet is complementary to this report, which provides a synthesis of the CASC-led climate-related, capacity-building activities for Tribes and Indigenous communities. The results described in this report provide an analysis of the categorization of projects, activities, and individual trainings to highlight detailed information on the various ways each CASC works with and supports Native and Indigenous communities.
An educational information packet about the 2025 List of Critical Minerals, which includes a memory match game about select critical minerals and how they are used.
The increasing use of computers for storing and analyzing earth science information has sparked a growth in the demand for various types of cartographic data in digital form. The production of map data in computerized form is called digital cartography, and it involves the collection, storage, processing, analysis, and display of map data with the aid of computers. The U.S. Geological Survey, the Nation's largest earth science research agency, has expanded its national mapping program to incorporate operations associated with digital cartography, including the collection of planimetric, elevation, and geographic names information in digital form. This digital information is available for use in meeting the multipurpose needs and applications of the map user community.
The purpose of the teaching package is to help students understand and use maps. The U.S. Geological Survey (USGS) has provided the package as a service to educators so that more Americans will learn to understand the world of information on maps. Everything in the package teaches and reinforces geographic skills that are required in your curriculum.
The Earth is very old - 4.5 billion years or more according to scientific estimates. Most of the evidence for an ancient Earth is contained in the rocks that form the Earth's crust. The rock layers themselves - like pages in a long and complicated history - record the events of the past, and buried within them are the remains of life - the plants and animals that evolved from organic structures that existed 3 billion years ago. Also contained in rocks once molten are radioactive elements whose isotopes provide Earth with an atomic clock. Within these rocks, 'parent' isotopes decay at a predictable rate to form 'daughter' isotopes. By determining the relative amounts of parent and daughter isotopes, the age of these rocks can be calculated. Thus, the scientific evidence from rock layers, from fossils, and from the ages of rocks as measured by atomic clocks attests to a very old Earth. See USGS Fact Sheet 2007-3015 at http://pubs.usgs.gov/fs/2007/3015/ for ages of geologic time periods. Ages in the spiral have been rounded from the age estimates in the Fact Sheet. B.Y., billion years; M.Y., million years. For more information, see the booklet on Geologic Time at http://pubs.usgs.gov/gip/geotime/. The Geologic Time Spiral poster is available for purchase from the USGS Store.
The first National Geo-Data Policy Forum was held on May 10-12, 1993, in Tyson's Corner, Virginia. The objective of the National Geo-Data Policy Forum was to examine policies related to the evolution and use of the National Spatial Data Infrastructure (NSDI). A second goal was to identify issues concerning spatial data technology and its use by all citizens. Policy makers from the public and private sectors offered ideas on the myriad issues and questions related to the NSDI and learned of concerns that their organizations must address. The links that connect the NSDI to the Clinton Administration's National Information Infrastructure were identified and discussed. The forum offered participants an opportunity to define the NSDI's role in carrying out technology policy.
The U.S. Geological Survey (USGS) National Water Quality Network for surface water (NWQN-SW) was established in 2013 to develop long-term, comparable assessments of surface-water quality in support of national, regional, state, and local needs related to water-quality management and policy. Waterquality samples are collected at each site and measured for a variety of parameters. In 2023, the NWQN-SW consisted of 109 sites, each of them paired with a streamgage, operated by the USGS or other agencies that provide continuous information on streamflow conditions. The waterquality data and the streamflow information from the NWQN-SW is then used to assess the status and trends of water-quality conditions and potential impacts on human and aquatic health.
The U.S. Geological Survey (USGS) National Water Quality Network for surface water (NWQN-SW) was established in 2013 to develop long-term, comparable assessments of surface-water quality in support of national, regional, State, and local needs related to water-quality management and policy. Water-quality samples are collected at each site and measured for a variety of constituents. In 2024, the NWQN-SW consisted of 105 sites, each of them paired with a streamgage, operated by the USGS or other agencies that provide continuous information on streamflow conditions. The water-quality data and the streamflow information from the NWQN-SW are then used to assess the status and trends of water-quality conditions and potential impacts on human and aquatic health.