Diane Noserale ( Phone: 703-648-4333 );
A map showing the many different pieces of Earth’s crust that comprise the nation’s geologic basement is now available from the U.S. Geological Survey. This is the first map to portray these pieces, from the most ancient to recent, by the events that influenced their composition, starting with their origin. This product provides a picture of the basement for the U.S., including Alaska, that can help scientists produce regional and national mineral resource assessments, starting with the original metal endowments in source rocks.
“Traditionally, scientists have assessed mineral resources using clues at or near the Earth’s surface to determine what lies below,” said USGS scientist Karen Lund, who led the project. “This map is based on the concept that the age and origins of basement rocks influenced the nature and location of mineral deposits. It offers a framework to examine mineral resources and other geologic aspects of the continent from its building blocks up,” said Lund.
More than 80 pieces of crust have been added to the nation’s basement since the Earth began preserving crust about 3.6 billion years ago. These basement domains had different ages and origins before they became basement rocks, and this map includes these as key factors that determined their compositions and the original metals that may be available for remobilization and concentration into ore deposits. The map further classifies the basement domains according to how and when they became basement, as these events also influence the specific metals and deposit types that might be found in a region.
Users can identify domains potentially containing specific metals or deposit types. They can configure the companion database to show the construction of the U.S. through time. The map also provides a template to correlate regional to national fault and earthquake patterns. The map is also available on a separate site, where users can combine data and overlay known mineral sites or other features on the domains.
Basement rocks are crystalline rocks lying above the mantle and beneath all other rocks and sediments. They are sometimes exposed at the surface, but often they are buried under miles of rock and sediment and can only be mapped over large areas using remote geophysical surveys. This map was compiled using a variety of methods, including data from national-scale gravity and aeromagnetic surveys.
Crustal rocks are modified several times before they become basement, and these transitions alter their composition. Basement rocks are continental crust that has been modified by a wide variety of plate tectonic events involving deformation, metamorphism, deposition, partial melting and magmatism. Ultimately, continental crust forms from pre-existing oceanic crust and overlying sediments that have been thus modified.
It is not only the myriad processes that result in varying basement rock content but also the time when these processes occurred during the Earth’s history. For example, because the Earth has evolved as a planet during its 4.5 billion year history, early deposit types formed when there was less oxygen in the atmosphere and the thin crust was hotter. The ancient domains are now more stable and less likely to be altered by modern processes that could cause metals to migrate. By contrast, basement rocks that formed out of crust that is less than one billion years old have origins that can be interpreted according to the present-day rates and scales of plate tectonic processes that reflect a more mature planet with a thicker crust.
By incorporating ancient to modern processes, this map offers a more complete and consistent portrait of the nation’s geologic basement than previous maps and presents a nationwide concept of basement for future broad-scale mineral resource assessments and other geologic studies.Map showing basement domains according to generalized original crust types. (High resolution image)
USGS scientists have updated the hydrogeologic framework for the Floridan aquifer system that underlies Florida and parts of Georgia, Alabama, and South Carolina.
The Floridan aquifer system is the principal source of freshwater for agricultural irrigation, industrial, mining, commercial, and public supply in Florida and southeast Georgia. The extensive underground reservoir currently supplies drinking water to about 10 million people residing across the area as well as 50% of the water that is used for agricultural irrigation in the region.
By describing the hydrologic and geologic setting of an aquifer, a hydrogeologic framework enables appropriate authorities and resource managers to monitor an aquifer more accurately, improving their ability to protect these critical resources and determine the near- and long-term availability of groundwater.
As the first update of the framework for the aquifer in over 30 years, the revision incorporates new borehole data into a detailed conceptual model that describes the major and minor units and zones of the system. Its increased accuracy is made possible by data collected in the intervening years by the USGS; the Geological Surveys of Alabama, Florida, Georgia, and South Carolina; the South Florida, Southwest Florida, St Johns River, Suwannee River, and Northwest Florida Water Management Districts; and numerous other state and local agencies.
The USGS is releasing two reports as part of its current assessment of groundwater availability of the Floridan aquifer system.
The first report documents the revised framework.
Williams, L.J., and Kuniansky, E.L., 2015, Revised hydrogeologic framework of the Floridan aquifer system in Florida and parts of Georgia, Alabama, and South Carolina: U.S. Geological Survey Professional Paper 1807, 140 p., 23 pls.
The second report provides datasets that describe the surfaces and thicknesses of selected hydrogeologic units of the Floridan aquifer system. The data depict the top and base of the aquifer system, its major and minor hydrogeologic units and zones, geophysical marker horizons, and the altitude of the 10,000-milligram-per-liter total dissolved solids boundary that defines the approximate fresh and saline parts of the aquifer system.
Williams, L.J., and Dixon, J.F., 2015, Digital surfaces and thicknesses of selected hydrogeologic units of the Floridan aquifer system in Florida and parts of Georgia, Alabama, and South Carolina: U.S. Geological Survey Data Series 926, 24 p.
The USGS is undertaking a series of regional groundwater availability studies to improve our understanding of groundwater availability in major aquifers across the Nation. Regional groundwater availability studies are currently underway to document the supply and demand of this important natural resource for the United States. To find out more about other related groundwater science activities, please visit the USGS Groundwater Resources Program website.
Jon Campbell ( Phone: 703-648-4180 );
The fourth volume of the comprehensive history of the U.S. Geological Survey, Minerals, Lands, and Geology for the Common Defence and General Welfare: Volume 4, 1939‒1961, has been issued as an electronic document.
Featuring more than 200 illustrations, the 704-page Volume 4 focuses on the United States and the USGS in war and peace from the beginning of World War II in Europe to the end of the administration of President Dwight D. Eisenhower. During this period, the USGS developed and adapted new instruments and methods that included airborne magnetometers and radiometers, advanced seismometers, stereoscopic plotters for topographic mapping, geophysical logging (detailed records of geologic formations penetrated by a borehole), and geological sampling from deep wells.
The late Mary C. Rabbitt (1915‒2002), a geophysicist who served with the USGS (1949‒1978), wrote the first three volumes in the series: Volume 1, Before 1879 (1979), Volume 2, 1879‒1904 (1980), and Volume 3, 1904‒1939 (1986). Volume 4 was begun by Rabbitt and completed by coauthor Clifford M. Nelson, a geologist with the USGS since 1976.
Like the earlier books in the series, Volume 4 places USGS operations in mapping and the earth sciences within the wider contexts of national and international history. For instance, USGS development of the airborne magnetometer — an instrument that traces the Earth’s magnetic field, enabling an effective method of exploring for subsurface minerals — followed from a wartime device that U.S. forces used to hunt enemy submarines in World War II.
In the foreword to Volume 4, Mark D. Myers, the 14th USGS Director (2006‒2009), wrote that the volume records USGS support of the Nation’s efforts during "a pivotal interval of transformation for the United States and the agency, …a time of great national sacrifice, rapid expansion of industrial capacity, spectacular scientific and technological advancement, and international leadership."
Volunteer citizen-mappers continue to make significant contributions to the USGS ability to provide accurate mapping information to the public. Recently, volunteers were asked to update all of the law enforcement structure points in Tennessee. The volunteers answered the call and added, verified, edited, or deleted an amazing 440 points!
In addition, all of the points were quality checked by either a peer reviewer or an advanced editor, so the data was ready to go into The National Map at the conclusion of the challenge.
The volunteer additions and edits will be symbolized on US Topo maps during the next production cycle for Tennessee, slated for next year.
An exciting addition to the mapping project is Mapping Challenges. The Challenges asks volunteers to concentrate on specific areas and structure types that need updating. In addition, Challenges encourage volunteers to remain engaged, and incentivizes participation. Once a need is determined, a call to action goes out to the volunteer corps with information on the geographic location and the type of structures that needs updating. Volunteers who participate can earn a series of virtual recognition badges and are recognized on social media and TNMCorps project site.
Using crowd-sourcing techniques, the USGS Volunteered Geographic Information (VGI) project, known as The National Map Corps (TNMCorps), encourages volunteers to collect manmade structures data in an effort to provide accurate and authoritative spatial map data for the National Geospatial Program’s web-based The National Map. Structures being updated include schools, hospitals, post offices, police stations and other important public buildings.
Special thanks to the volunteers who participated in this challenge: fconley, HGeisler, Cartograsaurus, TheJ, BCook2, rjerrard, Vindalou, Jwo_rocks, wesward, and alherna4.
"At times, locating structures seems similar to solving puzzles or detective work,” commented fconely, a Challenge veteran and one of the project’s more active participants.
Tools on TNMCorps project site explain how a volunteer can edit any area, regardless of their familiarity with the selected structures, and becoming a volunteer for TNMCorps is easy; register by going to The National Map Corps Editor. If you have access to the Internet and are willing to dedicate some time to editing map data, we hope you will consider participating.Screen-shot of the Tennessee Law Enforcement Facility Mapping Challenge showing the more than 440 edited points (green dots). At this scale, many dots contain more than one edited or verified structure. (high resolution image) The most recent status graphic showing the number and density of The National Map Corp submitted edits or verification for the past three years. (high resolution image)
A new online, interactive tool for estimating atrazine concentrations in streams and rivers is now available.
The online mapping tool can assist water managers, policy makers, and scientists in several ways, including:
- Understanding where and why pesticides occur in streams.
- Assessing geographic patterns in pesticide stream concentrations at many scales, ranging from the watershed to regional and national;
- Designing efficient and cost-effective monitoring programs and studies; and
- Identifying streams with the greatest likelihood to have concentrations that exceed a water-quality benchmark of potential concern.
“Assessment and management of pesticides require far more information on concentrations in streams and rivers than we can afford to directly measure for all the places and times of interest,” said Wes Stone, the USGS hydrologist who developed the model. “For these situations, statistical models can be used to estimate water-quality conditions at unmonitored locations under a range of possible circumstances.”
The estimates are based on a USGS statistical model — referred to as Watershed Regression for Pesticides (or “WARP”) — which also provides key statistics for each selected stream, including the probability that a pesticide may exceed a water-quality benchmark of potential concern, and a level of confidence and uncertainty associated with each estimate.
The release for atrazine is the first in a series of statistical models for other pesticides, each of which is based on USGS National Water-Quality Assessment (NAWQA) monitoring in streams from 1992-2011, agricultural pesticide use, and environmental characteristics, such as soil characteristics, hydrology, and climate.
Future updates will provide similar mapping and modeling for additional pesticides. Estimates and interactive mapping of pesticides for streams in the U.S. are available at this USGS website. The new website replaces an earlier version of the model for atrazine.
The U.S. Geological Survey expects to award up to $7 million in grants for earthquake hazards research in 2016.
“The USGS Earthquake Hazards Program annually provides grants to support research targeted toward improving our understanding of earthquake processes, hazards and risks,” said Bill Leith, USGS Senior Science Advisor for Earthquake and Geologic Hazards. “We seek cutting-edge proposals that will further our efforts to reduce losses from earthquakes, provide more accurate and timely earthquake information and forecasts and better inform the public about earthquake safety.”
Interested researchers can apply online at GRANTS.GOV under funding opportunity number G15AS00037. Applications are due May 19, 2015.
Every year the USGS awards earthquake research grants to universities, state geological surveys and private institutions. Past projects included:
- trench investigations to better understand the size and age of large earthquakes between Salt Lake City and Provo, Utah;
- the application of innovative techniques to map seismic hazards near the nation’s capital;
- exploring the use of rapid and precise GPS recordings to improve earthquake early warning;
- analysis of the potential for large earthquakes in the Gorgonio Pass, an area of complex faulting east of San Bernardino, California;
- investigation of recent earthquake activity along major fault lines crossing southeast Alaska; and
- studies to characterize and understand the causes of potentially induced earthquakes in California, Kansas, Wyoming, Texas, and Ohio.
A complete list of funded projects and reports can be found on the USGS Earthquake Hazards Program external research support website.
SPOKANE, Wash. — A new U.S. Geological Survey report covering major parts of the world’s largest mountain belt in central Asia estimates the existence of about five times as much copper in undiscovered deposits as has been identified to date. These areas host 20 known porphyry copper deposits, including the world class Oyu Tolgoi deposit in Mongolia that was discovered in the late 1990s.
The results of this new assessment estimate the probability that there may be as many as 97 undiscovered porphyry copper deposits within the assessed permissive tracts, which would represent nearly five times the 20 known deposits. Grade and tonnage models predict estimated resources associated with undiscovered deposits as mean values of 370,000,000 metric tons of copper, 10,000 t of gold, 7,700,000 t of molybdenum, and 120,000 t of silver. These estimated mean tonnages are predictions based on comparisons to known deposits of similar type.
Copper was one of the first metals ever extracted and used by humans, and it has been one of the important materials in the development of civilization. Because of its properties, of high ductility, malleability, and thermal and electrical conductivity, and its resistance to corrosion, copper has become a major industrial metal, ranking third after iron and aluminum in terms of quantities consumed.
USGS scientists worked in collaboration with colleagues in the China Geological Survey, the Centre for Russian and Central Eurasian Mineral Studies, and the Russian Academy of Sciences to complete the assessment. Participants evaluated applicable grade and tonnage models and estimated numbers of undiscovered deposits at different confidence levels for each permissive tract. The estimates were then combined with the selected grade and tonnage models using Monte Carlo simulations to generate probabilistic estimates of undiscovered resources. Additional resources in extensions of deposits with identified resources were not specifically evaluated.
The full report, USGS SIR 2010-5090-X, “Porphyry Copper Assessment of the Central Asian Orogenic Belt and eastern Tethysides— China, Mongolia, Russia, Pakistan, Kazakhstan, Tajikistan, and India,” is available online and includes a summary of the data used in the assessment, a brief overview of the geologic framework of the area, descriptions of permissive tracts and known deposits, maps, and tables. A geographic information system database that accompanies this report includes the tract boundaries and known porphyry copper deposits, significant prospects, and prospects. Assessments of overlapping younger rocks and adjacent areas are included in separate reports, which are also available online.
Appalachian coal and petroleum resources are still available in sufficient quantities to contribute significantly to fulfilling the nation’s energy needs, according to a recent study by the U.S. Geological Survey.
The Appalachian basin, which includes the Appalachian coalfields and the Marcellus Shale, covers parts of Alabama, Georgia, Kentucky, Maryland, New York, North Carolina, Ohio, Pennsylvania, Tennessee, Virginia and West Virginia.
“The study we conducted is a modern, in-depth collection of reports, cross sections and maps that describe the geology of the Appalachian basin and its fossil fuel resources,” said USGS scientist Leslie Ruppert, the study’s lead editor.
Petroleum resources, including oil and natural gas, remain significant in the Appalachian basin. Although both conventional oil and gas continue to be produced in the Appalachian basin, most new wells in the region are drilled in shale reservoirs, such as the famous Marcellus and Utica Shale, to produce natural gas.
The Appalachian basin contains significant coalbed methane and high-quality, thick, bituminous coal resources although the resource is deeper and thinner than the coal that has already been mined.
Although this volume is not a quantitative assessment of all notable geologic and fossil fuel localities in the Appalachian basin, the selected study areas and topics presented in the chapters pertain to large segments of the basin and a wide range of stratigraphic intervals. This updated geologic framework is especially important given the significance of shale gas in the basin.
This volume discusses the locations of coal and petroleum accumulations, the stratigraphic and structural framework, and the geochemical characteristics of the coal beds and petroleum in the basin, as well as the results of recent USGS assessments of coal, oil and gas resources in the basin.
Many of the maps and accompanying data supporting the reports in this volume are available from chapter I.1 as downloadable geographic information system (GIS) data files about the characteristics of selected coal beds and oil and gas fields, locations of oil and gas wells, coal production, coal chemistry, total petroleum system (TPS) boundaries and bedrock geology. Log ASCII Standard (LAS) files for geophysical (gamma ray) wireline well logs are included in other chapters.
USGS is the only provider of publicly available estimates of undiscovered technically recoverable oil and gas and coal resources of onshore lands and offshore state waters. This study of the Appalachian basin will underpin energy resource assessments and may be found online. To find out more about USGS energy assessments and other energy research, please visit the USGS Energy Resources Program website, sign up for our Newsletter, and follow us on Twitter.
The U.S. Geological Survey National Geospatial Program is pleased to announce the first round of awards resulting from the USGS Broad Agency Announcement (BAA) for the 3D Elevation Program (3DEP), initially issued on July 18, 2014. (Solicitation Number: G14PS00574).
The BAA is a publicly accessible process to develop partnerships for the collection of lidar and derived elevation data for 3DEP. The primary goal of 3DEP is to systematically collect nationwide lidar coverage (ifsar in Alaska) over an 8-year period to provide more than $690 million annually in new benefits to government entities, the private sector and citizens.
3DEP presents a unique opportunity for collaboration between all levels of government to leverage the services and expertise of private sector mapping firms that acquire the data, and to create jobs now and in the future. The USGS, along with other federal, state, local and private agencies, is establishing the collection program to respond to the growing needs for high-quality, three-dimensional mapping data of the United States.
“We are very excited about the high level interest in the BAA as demonstrated by the number and dollar value of the proposals we received,” said Kevin Gallagher, USGS Associate Director for Core Science Systems.
Current and accurate 3D elevation data are essential to help communities cope with natural hazards and disasters such as floods and landslides, support infrastructure, ensure agricultural success, strengthen environmental decision-making and bolster national security. Lidar, short for light detection and ranging, is a remote sensing detection system that works on the principle of radar, but uses light from a laser. Similarly, interferometric synthetic aperture radar (ifsar) is used to collect data over Alaska.
Federal funds to support this opportunity were provided by the USGS, the Federal Emergency Management Agency and the Natural Resources Conservation Service. The USGS is acting in a management role to facilitate planning and acquisition for the broader community, through the use of government contracts and partnership agreements.
The Fiscal Year 2015 Awards offered partnership funding to 29 proposals in 25 States and Territories. The FY15 body of work is expected to result in the influx of more than 95,000 square miles of public domain lidar point cloud data and derived elevation products into the 3DEP program.
More information about 3DEP including updates on current and future 3DEP partnership opportunities is available online.Map depicts the proposed body of work for 3DEP in Fiscal Year 2015. The BAA awards will add more than 95,000 square miles of 3DEP quality lidar data to the national database. (high resolution image 98 MB)
Thousands of photos and videos of the seafloor and coastline—most areas never seen before—are now available and easily accessible online. This is critical for coastal managers to make important decisions, ranging from protecting habitats to understanding hazards and managing land use.
Imagery is available through the U.S. Geological Survey (USGS) Coastal and Marine Geology Video and Photograph Portal.
This USGS portal is unique, due to the sheer quantity and quality of data presented. It is the largest database of its kind, providing detailed and fine-scale representations of the coast. The "geospatial context" is also unique, with maps displaying imagery in the exact location where it was recorded.
Prior to development of the data portal, retrieving this imagery required internal USGS access with specific hardware and software. It was difficult to manage and challenging to share such a large amount of information.
"The USGS has been dedicated to developing a system that allows for convenient communication internally as well as to outside collaborators and the public to access our abundance of coastal and seafloor imagery," said USGS geographer Nadine Golden, who is the Lead Principal Investigator for the USGS portal. "The portal makes it easy for users to discover, obtain and disseminate information."
This portal contains coverage of the seafloor off California and Massachusetts, and aerial imagery of the coastline along the Gulf of Mexico and mid-Atlantic coasts. Additional video and photographs will be added as they are collected, and archived imagery will also be incorporated soon. Areas of future focus include data sets for Washington State’s Puget Sound, Hawaii and the Arctic.
"As part of an ongoing seafloor mapping partnership, Massachusetts has worked with the USGS Woods Hole Science Center to map more than 850 square miles of marine waters and collect extensive video footage and photographs of the seafloor," said Massachusetts Office of Coastal Zone Management Director Bruce Carlisle. "The Coastal and Marine Geology Video and Photograph Portal is a great resource, providing direct and easy access to this imagery. It will support several key elements of the recently updated Massachusetts Ocean Management Plan, including habitat characterization and the review of ocean development projects under the plan."
Information in this portal helps create coastal maps and representations of seafloor composition and habitats. It provides references for short- and long-term monitoring of changes to the coast, whether from anthropogenic modifications or natural occurrences. Hurricanes and extreme storms are of particular concern, and USGS imagery helps managers, emergency responders and researchers understand circumstances before, during and after such events. Other critical hazards include coastal flooding and sea-level rise, as well as assessments for earthquake and tsunami awareness.
Data also support coastal and marine spatial planning, including evaluation of sites for renewable ocean energy facilities as well as the development of communities and infrastructure. USGS science helps designate marine protected areas, define habitats, identify needs for ecosystem restoration, and inform regional sediment management decisions.
In total, approximately 100,000 photographs and have been collected as well as 1,000 hours of trackline video covering almost 2,000 miles of coastline. Imagery was taken by video and still cameras towed by boat or from aerial flights.
This effort supports the National Ocean Policy mandate to provide access to federal data resources.
How does it work? Start with the tutorial and then dive in!
In 2013, a successful video and photograph pilot interactive website was launched for the California Seafloor Mapping Program, and this helped build the newly released portal.
Also, check out a new crowdsourcing application called, "USGS iCoast – Did the Coast Change?" This application allows citizen scientists to identify changes to the coast by comparing aerial photographs taken before and after storms.
Learn more about USGS science by visiting the USGS Coastal and Marine Geology Program website.Screenshot from the USGS Coastal and Marine Geology Video and Photograph Portal. Zooming into an area of interest reveals lines where continuous video footage was acquired and dots where still photographs were taken. Clicking on a segment launches the video in a pop-up window. Photographs appear beside the video, changing as the video passes each point where a photograph was taken. (High resolution image)
While the earth contains enough potash to meet the increased global demand for crop production and U.S. supplies are likely secure, some regions lack potash deposits needed for optimal food crop yields. According to a recent USGS global assessment of potash resources, the costs of importing potash long distances can limit its use and imports are subject to supply disruptions.
“Global scarcity is not the issue with potash – transportation costs are,” said USGS scientist Greta Orris, who led the assessment. “We chose to assess potash because it is used primarily for fertilizer and with the increasing global population, the need for agricultural lands to be increasingly productive will continue,” said Orris.
The U.S. imports more than 80 percent of the potash it uses, mostly from the Elk Point Basin in Saskatchewan, Canada. The Elk Basin is the world’s largest source of potash, having provided at least 20 percent of the world’s potash supply for nearly 40 years.
The U.S. produces potash from deposits in Utah and New Mexico. While production from the Michigan basin recently ceased, a large potash resource exists there. Production and development of resources in Michigan have been hindered by low potash prices, dated production equipment, and poor transport infrastructure amongst other factors. A significant potash resource in Arizona has also been identified, but resources in other states tend to be relatively small.
This global assessment, which includes a summary report and accompanying database, is the most complete, up-to-date, GIS-based, global compilation of information on known and potential potash resources from evaporite sources. The database includes more than 900 known potash deposits with measured resources. It also outlines 84 tracts throughout the world where undiscovered future resources might be found.
“A significant finding of this assessment is that there appears to be little to no potential to develop potash mines in either China or India, where large populations create the need for highly productive agricultural land, which in turn requires large amounts of appropriate fertilizers,” said Orris. “High import costs have resulted in lower usage of potash fertilizers than commonly seen in the U.S., and the potential for the land to be less productive.”
Potash includes a variety of minerals, ores, or processed products that contain potassium, one of three primary plant nutrients essential for growing food crops and biofuels. Modern agriculture requires large quantities of potassium so crop production is adequate to feed a growing population as arable land acreage becomes more limited. While potassium can be derived from other sources, conventional potash deposits – those formed by evaporation -- are the only cost- effective source for large quantities of potassium needed for high-yield agriculture.
The known deposits include location, geology, resource, production and other descriptive information. Potash-bearing basins may host tens of millions to more than 100 billion metric tons of potassium. Examples include Elk Point Basin in Canada, the Pripyat Basin in Belarus, the Solikamsk Basin in western Russia, and the Zechstein Basin in Germany.
The biggest potash producers are Canada, Russia, Belarus, and Israel. In addition to China and India, other areas lacking conventional deposits include much of Africa, Australia, and South America.
For the 84 tracts, the quantities of undiscovered resources are not estimated in this report. Instead, the tracts are classified into six categories that rank their potential to provide potash resources in 25 to 50 years based on known resources in the tract, level of available information, and whether geologic or other deficiencies, such as lack of water, power, or other infrastructure, could prevent or delay development of deposits. Potash tracts that may have potash deposits in production within the next five years include those in Ethiopia and the Republic of Congo.
More information on global and domestic potash, including demand, production, and uses is available from the USGS.
After surveying and analyzing centuries of evidence in the floodplain of the lower Roanoke River, USGS researchers, along with colleagues from the universities of Wisconsin and North Carolina, have developed a highly accurate estimate of sediment deposition amounts along the course of the river over three timescales — annual, decadal, and centennial.
The investigators used a range of techniques, including evidence from clay pads, tree-rings, and pollen analyses, at numerous locations (58 transects, 378 stations) and employed GIS technology to model sediment deposition rates and characteristics to gain insight into the sediment dynamics of the Roanoke, one of the largest river flood plains on the mid-Atlantic coast.
The scientists found that sediment deposition rates from AD 1725 to 1850 were an order of magnitude higher than present deposition rates and still affect the sediment dynamics of today. These high rates have been attributed to land clearance and poor agricultural practices during and after the colonial period. This legacy sediment deposition formed high banks upstream and the large, wide levees found along the middle reaches of the river.
Furthermore, dam operations, most notably the Kerr Dam completed in 1953, have reduced deposition on natural levees but facilitated backswamp deposition. A GIS-model of current river dynamics indicates that little sediment presently reaches Albemarle Sound because it is trapped on the floodplain, generally benefitting lower floodplain ecosystems and mitigating the transport of excess nutrients to coastal marine systems.
The study findings highlight the important role played by landscape alteration, including post-Colonial forest clearance and dam emplacement, in controlling modern sediment dynamics. The use of multiple techniques to determine sediment deposition rates should improve capabilities of developing accurate sediment budgets along different reaches of the river. In turn, this will aid predictions of the response of the river and associated habitats to changing sea level.
The research was recently published in the journal Geomorphology.
Marisa Lubeck ( Phone: 303-202-4765 );
New and improved science tools can help managers and researchers evaluate current threats and develop management strategies to protect and restore the valuable Great Lakes ecosystem.
The recently released U.S. Geological Survey products provide free environmental data to the public as part of the Great Lakes Restoration Initiative (GLRI), a collaborative effort to conserve the Great Lakes. The new GLRI Science Explorer and redesigned GLRI website (most compatible with the Google Chrome browser*), launched in November 2014, offer critical information pertaining to USGS GLRI projects, and allow researchers to contribute their own material. The interactive Science in the Great Lakes (SiGL) mapper was released in December 2014 and provides information about current and past Great Lakes studies.
Researchers, managers and the public can use the GLRI Science Explorer to find information about USGS GLRI science projects, as well as publications and datasets resulting from those projects. It currently contains information about 74 projects that are completed and in progress, 66 publications and 11 datasets. Science Explorer information is stored in ScienceBase, a cataloging and content management platform developed by the USGS, which allows for contributions from USGS scientists and collaborators.
“We are eagerly seeking contributions of data or metadata to the Science Explorer,” said USGS scientist Jessica Lucido.
The interactive SiGL mapper is a centralized place where researchers and managers can identify relevant scientific activities and access fundamental information about these efforts. It was designed to help coordinate all of the scientific projects in the Great Lakes Basin. SiGL captures information about any type of scientific activity and provides details on how to access the data and results from those projects.
“SiGL can help researchers and managers strategically plan, implement and analyze their monitoring and restoration activities,” said Jennifer Bruce, a USGS scientist. “We hope to encourage coordination and collaboration among all organizations throughout the Great Lakes Basin with this tool.”
SiGL contains over 250 projects and 10,500 sites, including all the USGS GLRI projects in the Science Explorer. Over 65 organizations have contributed to SiGL, including federal, state and local governments and agencies, tribes, universities and non-profit organizations. It provides information about general project details, specific sampling efforts, publications, data availability and access and contact information.
For more information about these and other USGS GLRI tools, please visit the USGS GLRI website.
The GLRI accelerates efforts to protect and restore the Great Lakes, the largest system of fresh surface water in the world. It targets the most significant problems in the region, including invasive aquatic species, pollution and contaminated sediment.
SPOKANE, Wash. — In cooperation with the Polish Geological Institute — National Research Institute, U.S. Geological Survey scientists have published a new assessment of copper resources in Poland and Germany. This investigation is part of the U.S. Geological Survey’s Global Mineral Resource Assessment. The study synthesizes available information on known resources and estimates the location and quantity of undiscovered copper associated with the well-known late Permian (approximately 255 million years old), carbon-enriched shale, the Kupferschiefer, of the Southern Permian Basin in Europe.
The ore deposits associated with the Kupferschiefer in Germany and Poland have been mined for over 800 years and are world-famous among geologists because research on these deposits played a significant role in the scientific debates on ore genesis. The largest Kupferschiefer copper deposit occurs in the Lubin-Sieroszowice mining area, Poland. It is the largest copper deposit in Europe and one of the largest copper deposits on the Earth.
Most of the known copper resource and almost all of the estimated undiscovered copper resources occur in southwestern Poland and adjacent parts of eastern Germany. Since 1958, about 15 million metric tons of copper have been produced, and about 30 million metric tons of discovered copper remains to be developed. The USGS estimates a mean value of 110 million metric tons of copper may be undiscovered to a depth of 2.5 km below the surface in this area. Most of the undiscovered resource in southwestern Poland would be deeper than 1.5 km, where virgin rock temperatures exceed 50 degrees C (122 degrees F).
In 800 years of mining, about 2.6 million metric tons of copper were produced from Kupferschiefer deposits in east-central Germany. The areas near the deposits in east-central Germany have been well explored; less than one million metric tons of discovered copper remain in identified deposits. Mean undiscovered copper estimates for this area are about 20 million metric tons.
This USGS study supports previous findings by the Polish Geological Institute for the amount of undiscovered copper in Poland. Mean values from the USGS study are remarkably similar to the values estimated by Polish geologists. The USGS study differs from the Polish study in that two different methods are used to probabilistically estimate the amount of undiscovered copper and maps are included to show where undiscovered resources are likely to occur.
The full report, USGS Scientific Investigations Report 2010–5090–U, “Assessment of undiscovered copper resources associated with the Permian Kupferschiefer, Southern Permian Basin, Europe,” by Michael Zientek and others, is available online.
Additional USGS mineral resource assessment results and reports, including previous volumes of this publication series, and an estimate of undiscovered copper resource of the world in 2013, are online.
The U.S. Geological Survey (USGS) has released a convenient and informative new method for the analysis of groundwater and surface-water hydrologic data called the Groundwater (GW) Toolbox. The GIS-driven graphical and mapping interface is a significant advancement in USGS software for estimating base flow (the groundwater-discharge component of streamflow), surface runoff, and groundwater recharge from streamflow data.
The GW Toolbox brings together several analysis methods previously developed by the USGS and Bureau of Reclamation. Each of the methods included with the GW Toolbox use daily streamflow data automatically retrieved from the USGS National Water Information System (NWIS) for more than 26,000 streamgage sites across the United States. In addition to streamflow data, the GW Toolbox facilitates the retrieval of groundwater-level and precipitation time-series data from the NWIS database.
The GW Toolbox will be of use to engineers, academia, and government agencies at all levels for the analysis of many of the water-budget components of a typical watershed. The intensively visual interface will help shed light on water availability and hydrologic trends in response to climate and land-use changes and variability in these watersheds.
The GW Toolbox runs in a Microsoft Windows environment and includes the Base Flow Index (BFI), HYSEP, and PART hydrograph-separation methods to estimate base flow and surface runoff and the RORA and RECESS methods to estimate groundwater recharge.