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At least 91 records · Page 5Linked to original sources
USGS2008

Ground-water levels in Huron County, Michigan, 2002-03

In 1990, the U.S. Geological Survey (USGS) completed a study of the hydrogeology of Huron County, Michigan (Sweat, 1991). In 1993, Huron County and the USGS entered into a continuing agreement to collect water-level altitudes (hereafter referred to as water levels) at selected wells throughout Huron County. As part of the agreement, USGS has operated four continuous water-level recorders, installed from 1988 to 1991 on wells in Bingham, Fairhaven, Grant, and Lake Townships (fig. 1) and summarized the data collected in an annual or bi-annual report. The agreement was altered in 2003, and beginning January 1, 2004, only the wells in Fairhaven and Lake Townships will have continuous water-level recorders, while the wells in Grant and Bingham Townships will revert to quarterly measurement status. USGS has also provided training for County or Huron Conservation District personnel to measure the water level, on a quarterly basis, in 23 wells. USGS personnel regularly accompany County or Huron Conservation District personnel to provide a quality assurance/quality control check of all measurements being made. Water-level data collected from the 23 quarterly-measured wells is also summarized in the annual or bi-annual report. In 1998, the USGS also completed a temporal and spatial analysis of the monitoring well network in Huron County (Holtschlag and Sweat, 1998). The altitude of Lake Huron and precipitation are good indicators of general climatic conditions and, therefore, provide an environmental context for groundwater levels in Huron County. Figure 2 shows the mean-monthly water-level altitude of Lake Huron, averaged from measurements made by the U.S. Army Corps of Engineers at sites near Essexville and Harbor Beach, and monthly precipitation measured in Bad Axe (National Oceanic and Atmospheric Administration [NOAA], 2002-04; Danny Costello, NOAA hydrologist, written commun., 2003-04). In March 2003, a new low-water level for the period of this study was measured in Lake Huron (National Oceanic and Atmospheric Administration, 2003; 2004). The net decline in the water level of Lake Huron from January 1, 2002 to December 31, 2003 was about 0.3 ft. Annual precipitation in 2002 was about 0.3 inches above normal, with much of it occurring during summer months. The provisional precipitation total for 2003 is about an inch below normal (NOAA, 2003, 2004; Danny Costello, NOAA hydrologist, written commun., 2003, 2004). Four wells equipped with continuous-data recorders are completed in the glacial, Saginaw, and Marshall aquifers. Water levels in three of the four wells equipped with continuous-data recorders experienced a net decline over the period from January 2002 to December 2003, while the level in well H9r, completed in the Saginaw aquifer in Fairhaven Township adjacent to Saginaw Bay (Lake Huron), rose about 1.3 ft over the same period. Interestingly, the water level in Saginaw Bay declined about 0.3 ft over the same period. A period-ofrecord maximum depth to water was recorded in September 2003 in well H25Ar, completed in the Marshall aquifer in Lake Township. Hydrographs showing altitude of the water surface are presented for each of four wells equipped with continuous-data recorders. Twenty three wells were measured on a quarterly basis in 2002-03. These wells are completed in the Saginaw and Marshall aquifers, and Coldwater confining unit. Although each quarterly measurement only provides a “snapshot” water level, the data adequately define the “generalized” water-level trend in the aquifer near the well. The water level in one quarterly-measured well completed in the Saginaw aquifer near Saginaw Bay, had a net rise for the period from January 2002 to December 2003, while levels in the other 22 quarterly-measured wells declined about 0.5 to 2.0 ft during the same period. A period-of-record minimum depth to water (high) was measured in 2002 in two quarterly-measured wells completed in the Saginaw aquifer, although the level in one of those wells had a net decline over the period from January 2002 through December 2003. Conversely, period-of-record maximum depths to water (low) were measured in 2002 in one well completed in the Saginaw aquifer and two wells completed in the Marshall aquifer; and in 2003, in 6 of 16 wells completed in the Marshall aquifer. Near period-ofrecord maximum depths to water were measured in 2003 in two additional wells completed in the Marshall aquifer. No period-of-record minimum or maximum depths to water were measured in 2002-03 in wells completed in the Coldwater confining unit. Hydrographs showing water levels measured in each well are presented for the 23 wells measured on a quarterly basis. Water-level trends measured in 2002-03 in other wells in Lower Michigan have similarities to those measured in Huron County wells. Several external factors appear to influence water-level trends including proximity to nearby production wells, amount and timing of precipitation events, evapotranspiration and type of prevalent ground cover, proximity of aquifer to the surface, and hydraulic characteristics of overlying geologic materials.

Michigan↗
USGS2006

Under the Golden Gate Bridge — Views of the sea floor near the entrance to San Francisco Bay, California

San Francisco Bay in Northern California is one of the largest and most altered estuaries within the United States. The sea floor within the bay as well as at its entrance is constantly changing due to strong tidal currents, aggregate mining, dredge disposal, and the creation of new land using artificial fill. Understanding this dynamic sea floor is critical for addressing local environmental issues, which include defining pollution transport pathways, deciphering tectonics, and identifying benthic habitats. Mapping commercial interests such as safe ship navigation and dredge disposal is also significantly aided by such understanding. Over the past decade, the U.S. Geological Survey (USGS), the National Oceanic and Atmospheric Administration (NOAA), and California State University, Monterey Bay (CSUMB) in cooperation with the U.S. Army Corps of Engineers (USACOE) and the Center for Integrative Coastal Observation, Research and Education (CICORE) have partnered to map central San Francisco Bay and its entrance under the Golden Gate Bridge using multibeam echosounders. These sonar systems can continuously map to produce 100 percent coverage of the sea floor at meter-scale resolution and thus produce an unprecedented view of the floor of the bay. This poster shows views of the sea floor in west-central San Francisco Bay around Alcatraz and Angel Islands, underneath the Golden Gate Bridge, and through its entrance from the Pacific Ocean. The sea floor is portrayed as a shaded relief surface generated from the multibeam data color-coded for depth from light blues for the shallowest values to purples for the deepest. The land regions are portrayed by USGS digital orthophotographs (DOQs) overlaid on USGS digital elevation models (DEMs). The water depths have a 4x vertical exaggeration while the land areas have a 2x vertical exaggeration.

California↗
USGS1971

Ship canals and aquatic ecosystems

Through a combination of ecosystem homeostasis and the perversity of man and nature, oftentimes the significant biological changes effected by environmental modifications are not detected until long after the initial change has taken place. The immediate impact, which may range from the spectacular to the undetectable, is a deceptive measure of the long-term and often more important changes in the ecosystem. Two major engineering achievements illustrate this premise: (i) construction of the Erie Canal, which provided access from the Atlantic Ocean to the Great Lakes, and the Welland Canal, which bypasses the block between Lakes Ontario and Erie created by Niagara Falls (Fig. 1), and (ii) construction of the Suez Canal between the Red Sea and the Mediterranean Sea.

Science↗
USGS1978

On the development of strong-motion instrument networks in the United States

This report outlines a plan for the distribution of strong-motion instrumentation throughout the United States. The present "national" network of strong-motion instrumentation has evolved through the merger of several programs initiated by different agencies and organizations with objectives ranging from research to regulation. It is the result of the coordination of instrument maintenance and record archival currently provided by the Seismic Engineering Branch of the U.S. Geological Survey (formerly the Seismological Field Survey of the U.S. Coast & Geodetic Survey, or the National Ocean Survey, or the National Oceanic and Atmospheric Administration). The USGS operates the program under funding from the National Science Foundation (NSF) in cooperation with other federal, state, and local agencies. NSF supports a data management function and the operation of a network of about 200 accelerographs and 300 seismoscopes utilized for studies of ground motion and building response. The State of California is developing its own strong-motion instrumentation program (CSMIP), which includes measurements of ground motion as well as the response of representative types of structures. The CSMIP network is the largest network operated by a single agency anywhere in the world. Eventually it will contain a total of about 1000 accelerographs. The Army Corps of Engineers (COE) is developing a program for monitoring the response of earth dams, which eventually will include as many as 400 instruments on over 100 dams. Other agencies and organizations are developing networks appropriate to their missions or objectives. At present the number of instruments owned by these other agencies is less than 100 in each case, although several agencies are still expanding their networks. The present distribution of accelerographs in the United States is indicated in Figure 1 (see: USGS, 1977, also). In 1964 the cities of Los Angeles and Beverly Hills, California passed ordinances which required 3 accelerographs to be installed in all high-rise buildings. Initially, these instruments were installed and maintained as a part of the strong-motion program of the Seismological Field Survey (SFS). As the number of installations required by such codes increased, it became apparent that the maintenance of these instruments placed an inordinate burden on and created an imbalance in the SFS operated program (in 1972, 50 percent of the "national" program was concentrated in Los Angeles). With the transfer of the SFS program responsibility to the NSF and with the development of the CSMIP, the responsibility for maintenance of code required instruments has reverted to the city building officials and the building owners. As the coordinated network of strong-motion instruments has grown, the maintenance of the instruments has required a larger staff than the USGS could provide under existing personnel ceilings. This situation has been resolved by the agencies with the larger networks performing their own installation and maintenance. The USGS maintains an archive of first class copies of all records, whereas other agencies maintain archives of their own records, only. In addition, the USGS coordinates the routine processing of all of the significant records, although other agencies will process their own data if they consider it to have a higher priority than does the USGS. In response to a recent change in their legislated charter, the CSMIP is beginning to develop a capability to process the data collected under that program.

Open-File Report↗
USGS1999

Scientists in action!

News about careers in the natural sciences—from mapping the planets to sampling the ocean floor, from protecting wildlife to forecasting volcanic eruptions.

Report↗
USGS2005

Scientists in action

News about careers in the natural sciences -- from mapping the planets to sampling the ocean floor, from protecting wildlife to forecasting volcanic eruptions.

General Information Product↗
USGS2021

Historical streamflow and stage data compilation for the Lower Columbia River, Pacific Northwest

The U.S. Geological Survey mined data from a variety of national and state agencies including USGS, Oregon Water Resources Department, National Oceanic and Atmospheric Administration, Washington Department of Ecology, Pacific Northwest National Laboratory, Portland State University, and U.S. Army Corps of Engineers. A comprehensive dataset of streamflow, stage, and tidal elevations for the Lower Columbia River basin was compiled. Data were compiled from gaging stations in Oregon and Washington along the Columbia River from Astoria to The Dalles and along the Willamette River from Salem to Portland. Tidal gages along the Washington, Oregon, and California coasts were also compiled. Seasonal maximum values were calculated for both streamflow and stage for the winter (November–March) and spring (April–July) flow seasons, as well as for the full water year when underlying data were available. The aggregated datasets are available at https://doi.org/10.5066/P9R6RT0Z .

California, Oregon, Washington↗
USGS1978

Coastal mapping handbook

Passage of the Coastal Zone Management Act of 1972 focused attention on the Nation's coastal land and water areas. As plans for more effective management of the coastal zone evolved, it soon became apparent that improved maps and charts of these areas were needed. This handbook was prepared with the requirements of the entire coastal community in mind, giving greatest attention to the needs of coastal zone managers and planners at the State and local levels. Its principal objective is to provide general information and guidance; it is neither a textbook nor a technical manual, but rather a primer on coastal mapping. This handbook should help planners and managers of coastal programs to determine their mapping requirements, select the best maps and charts for their particular needs, and to deal effectively with personnel who gather data and prepare maps. The sections on "Sources of Assistance and Advice" and "Product and Data Sources" should be especially useful to all involved in mapping the coastal zone. Brief summaries of the mapping efforts of several State coastal zone management programs are included. "Future outlook" discusses anticipated progress and changes in mapping procedures and techniques. Illustrations are inserted, where appropriate, to illustrate the products and equipment discussed. Because of printing restrictions, the colors in map illustrations may vary from those in the original publication. The appendixes include substantial material which also should be of interest. In addition a glossary and an index are included to provide easy and quick access to the terms and concepts used in the text. For those interested in more technical detail than is provided in this handbook, the "Selected references" will be useful. Also, the publications of the professional societies listed in appendix 4 will provide technical information in detail.

Report↗
USGS2006

Tsunami hazards— A national threat

In December 2004, when a tsunami killed more than 200,000 people in 11 countries around the Indian Ocean, the United States was reminded of its own tsunami risks. In fact, devastating tsunamis have struck North America before and are sure to strike again. Especially vulnerable are the five Pacific States--Hawaii, Alaska, Washington, Oregon, and California--and the U.S. Caribbean islands. In the wake of the Indian Ocean disaster, the United States is redoubling its efforts to assess the Nation's tsunami hazards, provide tsunami education, and improve its system for tsunami warning. The U.S. Geological Survey (USGS) is helping to meet these needs, in partnership with the National Oceanic and Atmospheric Administration (NOAA) and with coastal States and counties.

Fact Sheet↗
USGS2018

Social attraction used to establish Caspian tern (Hydroprogne caspia) nesting colonies on modified islands at the Don Edwards San Francisco Bay National Wildlife Refuge, California—Final report

To address the 2008/2010 and Supplemental 2014 National Oceanic and Atmospheric Administration Fisheries Biological Opinion for operation of the Federal Columbia River Power System, the U.S. Army Corps of Engineers (USACE) and the Bureau of Reclamation (Reclamation) developed and began implementation of Caspian tern ( Hydroprogne caspia ) management plans. This implementation includes redistribution of the Caspian terns in the Columbia River estuary and the mid-Columbia River region to reduce predation on salmonids listed under the Endangered Species Act. Key elements of the plans are (1) reduction of nesting habitat for Caspian terns in the Columbia River estuary and the mid-Columbia River region, and (2) creation or modification of nesting habitat at alternative sites within the Caspian tern breeding range. As part of this effort, USACE and Reclamation developed Caspian tern nesting habitat at the U.S. Fish and Wildlife Service Don Edwards San Francisco Bay National Wildlife Refuge (DENWR), California, prior to the 2015 nesting season. Furthermore, nesting habitat for western snowy plovers ( Charadrius alexandrinus nivosus ) also was developed to provide separate nesting opportunities in the same managed ponds to reduce potential conflicts with Caspian terns. Specifically, seven recently constructed islands within two managed ponds (Ponds A16 and SF2) of DENWR were modified to provide habitat attractive to nesting Caspian terns (5 islands) and snowy plovers (2 islands). These 7 islands were a subset of 46 islands recently constructed in Ponds A16 and SF2 to provide waterbird nesting habitat as part of the South Bay Salt Pond (SBSP) Restoration Project. We used social attraction methods (decoys and electronic call systems) to attract Caspian terns and snowy plovers to these seven modified islands, and conducted surveys from March to September of 2015, 2016, and 2017 to evaluate nest numbers, nest density, and productivity. Results from the 2015 nesting season, the first year of the study, indicated that island modifications and social attraction measures were successful in establishing Caspian tern breeding colonies at Ponds A16 and SF2 of DENWR. Prior to 2015, there was no history of Caspian terns nesting in either Pond A16 or Pond SF2. The success of 2015 continued in 2016 and 2017. In 2017, the third and final year of the project, Caspian terns initiated at least 664 nests, fledged at least 239 chicks, and had a breeding success rate of 0.36 fledged chicks per breeding pair. This represents a 171 percent increase in the number of breeding pairs and a 41 percent increase in the number of chicks fledged, but a 48 percent decrease in the fledglings produced per breeding pair in 2017 compared to 2015, the first year the colonies were established. The two new large and growing Caspian tern nesting colonies at Ponds A16 and SF2 demonstrate the effectiveness of social attraction measures in helping to establish tern nesting colonies in San Francisco Bay. Social attraction measures similar to those used in this study, but targeting other colonial species such as Forster’s terns ( Sterna forsteri ) and American avocets ( Recurvirostra americana ), may help to establish waterbird breeding colonies at wetlands enhanced as part of the SBSP Restoration Project.

California↗
USGS2012

Water-quality, bed-sediment, and discharge data for the Mississippi River-Gulf Outlet and adjacent waterways, southeastern Louisiana, August 2008 through December 2009

The Mississippi River-Gulf Outlet navigation channel (MRGO) was constructed in the early 1960s to provide a safer and shorter route between the Gulf of Mexico and the Port of New Orleans for deep-draft, ocean-going vessels and to promote the economic development of the Port of New Orleans. In 2006, the U.S. Army Corps of Engineers developed a plan to de-authorize the MRGO. The plan called for a rock barrier to be constructed across the MRGO near Bayou La Loutre. In 2008, the U.S. Geological Survey, in cooperation with the Louisiana Coastal Area Science and Technology Program began a study to document the impacts of the rock barrier on water-quality and flow before, during, and after its construction. Water-quality, bed-sediment, and discharge data were collected in the MRGO and adjacent water bodies from August 2008 through December 2009.

Louisiana↗
USGS1988

Methane hydrate - A major reservoir of carbon in the shallow geosphere?

Methane hydrates are solids composed of rigid cages of water molecules that enclose methane. Sediment containing methane hydrates is found within specific pressure-temperature conditions that occur in regions of permafrost and beneath the sea in outer continental margins. Because methane hydrates are globally widespread and concentrate methane within the gas-hydrate structure, the potential amount of methane present in the shallow geosphere at subsurface depths of < ???2000 m is very large. However, estimates of the amount are speculative and range over about three orders of magnitude, from 2 ?? 103 to 4 ?? 106 Gt (gigatons = 1015 g) of carbon, depending on the assumptions made. The estimate I favor is ??? 1 ?? 104 Gt of carbon. The estimated amount of organic carbon in the methane-hydrate reservoir greatly exceeds that in many other reservoirs of the global carbon cycle - for example, the atmosphere (3.6 Gt); terrestrial biota (830 Gt); terrestrial soil, detritus and peat (1960 Gt); marine biota (3 Gt); and marine dissolved materials (980 Gt). In fact, the amount of carbon may exceed that in all fossil fuel deposits (5 ?? 103 Gt). Because methane hydrates contain so much methane and occur in the shallow geosphere, they are of interest as a potential resource of natural gas and as a possible source of atmospheric methane released by global warming. As a potential resource, methane hydrates pose both engineering and production problems. As a contributor to a changing global climate, destabilized methane hydrates, particularly those in shallow, nearshore regions of the Arctic Ocean, may have some effect, but this effect will probably be minimal, at least during the next 100 years. ?? 1988.

Chemical Geology↗
USGS2013

Archive of post-Hurricane Isabel coastal oblique aerial photographs collected during U.S. Geological Survey Field Activity 03CCH01 from Ocean City, Maryland, to Fort Caswell, North Carolina and Inland from Waynesboro to Redwood, Virginia, September 21 - 23, 2003

On September 21 - 23, 2003, the United States Geological Survey (USGS) conducted an oblique aerial photographic survey along the Atlantic coast from Ocean City, Md., to Fort Caswell, N.C., and inland oblique aerial photographic survey from Waynesboro to Redwood, Va., aboard a Navajo Piper twin-engine airplane. The coastal survey was conducted at an altitude of 500 feet (ft) and approximately 1,000 ft offshore. For the inland photos, the aircraft tried to stay approximately 500 ft above the terrain. These coastal photos were used to document coastal changes like beach erosion and overwash caused by Hurricane Isabel, while the inland photos looked for potential landslides caused by heavy rains. The photos may also be used as baseline data for future coastal change analysis. The USGS and the National Aeronautics and Space Administration (NASA) surveyed the impact zone of Hurricane Isabel to better understand the changes in vulnerability of the Nation’s coasts to extreme storms (Morgan, 2009). This report serves as an archive of photographs collected during the September 21 - 23, 2003, post-Hurricane Isabel coastal and inland oblique aerial survey along with associated survey maps, KML files, navigation files, digital Field Activity Collection System (FACS) logs, and Federal Geographic Data Committee (FGDC) metadata. Refer to the Acronyms page for expansions of all acronyms and abbreviations used in this report. The USGS St. Petersburg Coastal and Marine Science Center (SPCMSC) assigns a unique identifier to each cruise or field activity. For example, 03CCH01 tells us the data were collected in 2003 for the Coastal Change Hazards (CCH) study and the data were collected during the first field activity for that project in that calendar year. Refer to http://walrus.wr.usgs.gov/infobank/programs/html/definition/activity.html for a detailed description of the method used to assign the ID number. The photographs provided here are Joint Photographic Experts Group (JPEG) scanned images of the analog 35 millimeter (mm) color positive slides. The photograph locations are estimates of the location of the plane (see the Navigation page). The metadata values for photo creation time, GPS latitude, GPS longitude, GPS position (latitude and longitude), keywords, credit, artist, caption, copyright, and contact were added to each photograph's EXIF header using EXIFtool (Subino and others, 2012). Photographs can be opened directly with any JPEG-compatible image viewer by clicking on a thumbnail on the contact sheet, or, when viewing the Google Earth KML file, by clicking on the marker and then clicking on either the thumbnail or the link below the thumbnail. Nathaniel Plant (USGS - St. Petersburg, Fla.), and Ann Marie Ascough (formerly contracted at the USGS - St. Petersburg, Fla.) helped with the creation of KML files. To view the photos and survey maps, proceed to the Photos and Maps page.

Maryland, North Carolina, Virginia↗
USGS2015

Indian National Gas Hydrate Program Expedition 01 report

Gas hydrate is a naturally occurring &ldquo;ice-like&rdquo; combination of natural gas and water that has the potential to serve as an immense resource of natural gas from the world&rsquo;s oceans and polar regions. However, gas-hydrate recovery is both a scientific and a technical challenge and much remains to be learned about the geologic, engineering, and economic factors controlling the ultimate energy resource potential of gas hydrate. The amount of natural gas contained in the world&rsquo;s gas-hydrate accumulations is enormous, but these estimates are speculative and range over three orders of magnitude from about 2,800 to 8,000,000 trillion cubic meters of gas. By comparison, conventional natural gas accumulations (reserves and undiscovered, technically recoverable resources) for the world are estimated at approximately 440 trillion cubic meters. Gas recovery from gas hydrate is hindered because the gas is in a solid form and because gas hydrate commonly occurs in remote Arctic and deep marine environments. Proposed methods of gas recovery from gas hydrate generally deal with disassociating or &ldquo;melting&rdquo; in situ gas hydrate by heating the reservoir beyond the temperature of gas-hydrate formation, or decreasing the reservoir pressure below hydrate equilibrium. The pace of energy-related gas hydrate assessment projects has accelerated over the past several years. The Indian National Gas Hydrate Program Expedition 01 was designed to study the gas-hydrate occurrences off the Indian Peninsula and along the Andaman convergent margin with special emphasis on understanding the geologic and geochemical controls on the occurrence of gas hydrate in these two diverse settings. During Indian National Gas Hydrate Program Expedition 01, dedicated gas-hydrate coring, drilling, and downhole logging operations were conducted from 28 April 2006 to 19 August 2006.

Krishna-Godivari Basin↗