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Statistics of petroleum exploration in the Caribbean, Latin America, Western Europe, the Middle East, Africa, non-communist Asia, and the southwestern Pacific

This circular presents a summary of the geographic location, amount, and results of petroleum exploration, including an atlas showing explored and delineated prospective areas through 1990. The data show that wildcat well drilling has continued through the last decade to expand the prospective area by about 40,000 to 50,000 square miles per year. However, the area delineated by 1970, which represents only about one-third of the prospective area delineated to date, contains about 80 percent of the oil discovered to date. This discovery distribution suggests that, from an overall prospective, the industry was successful in delineating the most productive areas early. The price increases of the 1970's and 1980's allowed the commercial exploration and development of fields in high-cost areas, such as the North Sea and Campos Basin, Brazil. Data on natural-gas discoveries also indicate that gas will be supplying an increasing share of the worldwide energy market. The size distribution of petroleum provinces is highly skewed. The skewed distribution and the stability in province size orderings suggest that intense exploration in identified provinces will not change the distribution of oil within the study area. Although evidence of the field-growth phenomenon outside the United States and Canada is presented, the data are not yet reliable enough for projecting future growth. The field-growth phenomenon implies not only that recent discoveries are substantially understated, but that field growth could become the dominant source of additions to proved reserves in the future.

Circular↗

Outer continental shelf oil and gas activities in the Pacific (Southern California) and their onshore impacts: a summary report, May 1980

Outer Continental Shelf (OCS) oil and gas exploration and development have been under way in the Pacific (Southern California) Region since 1966. During that time, there have been four Federal lease sales: in 1966, 1968, 1975 (Sale 35), and 1979 (Sale 48). Oil and gas production from three leases has been going on since 1968. It peaked in 1971 and now averages around 31,400 barrels of oil and 15.4 million cubic feet of gas per day. Discoveries on areas leased in the 1968 and 1975 sales have led to plans for eight new platforms to begin production in the early 1980's. Five platforms are in the eastern end of Santa Barbara Channel, one is in the western Channel, and two are in San Pedro Bay, south of Long Beach. Three rigs are doing exploratory drilling in the Region. The most recent estimates by the U.S. Geological Survey of remaining reserves for all identified fields in the Southern California Region are 695 million barrels of oil and 1,575 billion cubic feet of gas (January 1979). The USGS has also made risked estimates of economically recoverable oil and gas resources for all the leased tracts in the Region (March 1980). These risked estimates of economically recoverable resources are 394 billion barrels of oil and 1,295 billion cubic feet of gas. The USGS estimates of undiscovered recoverable resources for the entire Southern California OCS Region (January 1980) are 3,200 million barrels of oil and 3,400 billion cubic feet of gas. Because of the long history of oil and gas production in Southern California from wells onshore and in State waters, there are many existing facilities for the transportation, processing, and refining of oil and gas. Some of the expected new OCS production can be accommodated in these facilities. Four new onshore projects will be required. Two of these are under construction: (1) a 9.6-km (6-mi) onshore oil pipeline (capacity: 60,000 bpd) between Carpinteria (Santa Barbara County) and the existing Mobil-Rincon separation and treatment facility (Ventura County), and (2) a small supply base and dock (upgrade of existing facility) and a 0.4-hectare (1-acre) crude oil distribution facility in Long Beach (Los Angeles County), connected to landfall by a 3-km (1.8-mi) onshore pipeline. The two other facilities are awaiting permit approval: (1) a gas treatment plant at Las Flores Canyon (Santa Barbara County) and (2) a separation and treatment plant at Mandalay Beach (Ventura County) with 4 km (2.5 mi) of onshore pipeline on the same right-of-way from landfall to the plant and from the plant to an existing gas transmission line.

California↗

Marshes to mudflats—Effects of sea-level rise on tidal marshes along a latitudinal gradient in the Pacific Northwest

Summary In the Pacific Northwest, coastal wetlands support a wealth of ecosystem services including habitat provision for wildlife and fisheries and flood protection. The tidal marshes, mudflats, and shallow bays of coastal estuaries link marine, freshwater, and terrestrial habitats, and provide economic and recreational benefits to local communities. Climate change effects such as sea-level rise are altering these habitats, but we know little about how these areas will change over the next 50–100 years. Our study examined the effects of sea-level rise on nine tidal marshes in Washington and Oregon between 2012 and 2015, with the goal of providing scientific data to support future coastal planning and conservation. We compiled physical and biological data, including coastal topography, tidal inundation, vegetation structure, as well as recent and historical sediment accretion rates, to assess and model how sea-level rise may alter these ecosystems in the future. Multiple factors, including initial elevation, marsh productivity, sediment availability, and rates of sea-level rise, affected marsh persistence. Under a low sea-level rise scenario, all marshes remained vegetated with little change in the present configuration of communities of marsh plants or gradually increased proportions of middle-, high-, or transition-elevation zones of marsh vegetation. However, at most sites, mid sea-level rise projections led to loss of habitat of middle and high marshes and a gain of low marshes. Under a high sea-level rise scenario, marshes at most sites eventually converted to intertidal mudflats. Two sites (Grays Harbor and Willapa) seemed to have the most resilience to a high rate of rise in sea-level, persisting as low marsh until at least 2110. Our main model finding is that most tidal marsh study sites are resilient to sea-level rise over the next 50–70 years, but that sea-level rise will eventually outpace marsh accretion and drown most habitats of high and middle marshes by 2110.

California, Oregon, Washington↗

Archive of Digital Chirp Subbottom Profile Data Collected During USGS Cruise 14BIM05 Offshore of Breton Island, Louisiana, August 2014

From August 11 to 31, 2014, the U.S. Geological Survey ( USGS ), in cooperation with the U.S. Fish and Wildlife Service ( USFWS ), conducted a geophysical survey to investigate the geologic controls on barrier island framework and long-term sediment transport offshore of Breton Island, Louisiana as part of a broader USGS study on Barrier Island Mapping ( BIM ). Additional details related to this activity can be found by searching the USGS's Coastal and Marine Geoscience Data System (CMGDS), for field activity 2014-317-FA (also known as 14BIM05). These surveys were funded through the USGS Coastal and Marine Geology Program ( CMGP ) and the Louisiana Outer Coast Early Restoration Project. This report serves as an archive of unprocessed digital chirp subbottom data, trackline maps, navigation files, Geographic Information System ( GIS ) files, Field Activity Collection System ( FACS ) logs, and formal Federal Geographic Data Committee ( FGDC ) metadata. Gained digital images of the seismic profiles are also provided. Refer to the Abbreviations page for explanations of acronyms and abbreviations used in this report. All chirp systems use an acoustic signal of continuously varying frequency; the EdgeTech 512i system used during this survey produced high-resolution, shallow-penetration (typically less than 50 milliseconds [ ms] ) profile images of sub-seafloor stratigraphy. The towfish contains a transducer that transmits and receives acoustic energy and typically is towed 1–2 meters ( m ) below the sea surface. As transmitted acoustic energy intersects density boundaries, such as the seafloor or sub-surface sediment layers, some energy is reflected back toward the transducer, received, and recorded by a Personal Computer ( PC) -based seismic acquisition system. This process is repeated at regular intervals (for example, 0.125 seconds ( s) ) and returned energy is recorded for a specific duration (for example, 50 ms ). In this way, a two-dimensional ( 2-D ) vertical image of the shallow geologic structure beneath the ship's track is produced. Figure 2 displays the acquisition geometry. Refer to table 1 for a summary of acquisition parameters and table 2 for trackline statistics. The archived trace data are in standard SEG Y rev. 0 format (Barry and others, 1975); the first 3,200 bytes of the card image header are in American Standard Code for Information Interchange ( ASCII ) format instead of Extended Binary Coded Decimal Interchange Code ( EBCDIC ) format. The SEG Y files are available on the DVD version of this report or online, downloadable via the USGS Coastal and Marine Geoscience Data System ( http://cmgds.marine.usgs.gov ). The data are also available for viewing using GeoMapApp ( http://www.geomapapp.org ) and Virtual Ocean ( http://www.virtualocean.org ) multi-platform open source software. The Web version of this archive does not contain the SEG Y trace files. To obtain the complete DVD archive, contact USGS Information Services at 1-888-ASK-USGS or infoservices@usgs.gov. The SEG Y files may be downloaded and processed with commercial or public domain software such as Seismic Unix ( SU ) (Cohen and Stockwell, 2010). See the How To Download SEG Y Data page for download instructions. The printable profiles are provided as Graphics Interchange Format ( GIF ) images processed and gained using SU software and can be viewed from the Profiles page or by using the links located on the trackline maps; refer to the Software page for links to example SU processing scripts.

Louisana↗

USGS invasive carp database management and integration support

Invasive carp tracking, monitoring, and contracted removal will continue throughout the Illinois River and upper Mississippi River as part of an adaptive management effort to mitigate, control, and contain invasive carp. To facilitate these actions, a need to compile and analyze invasive carp-related data from all agencies exists. Invasive carp-related data include all data sources that could inform the MRWG objectives or projects. These data, often in disparate formats, must be integrated into a common format that allows all agencies the opportunity to assess invasive carp monitoring, control, and removal efforts. Ensuring the interoperability of these datasets allows for their use in various analyses and modeling efforts. Implementing an interoperable data management framework provides mechanisms for endusers to find and use integrated data. Integrating data for use in modeling and analysis furthers the partnership’s collective understanding of invasive carp life history, distribution, and movement and can be used to facilitate adaptive management actions (e.g., directing monitoring, sampling, and removal efforts, assessing invasive carp abundance to support modeling efforts, informing deployment of control actions, etc.). An effective data management strategy will streamline the data update process, providing all agencies with timely data and analyses in support of informed decision-making processes.

Interim Summary Report↗

USGS invasive carp database management and integration support

Invasive carp tracking, monitoring, and contracted removal will continue throughout the Illinois River and upper Mississippi River as part of an adaptive management effort to mitigate, control, and contain invasive carp. Other fish will also be tracked to maintain a holistic view of the transmitter distribution in the Upper IWW. To facilitate these actions, a need to compile and analyze invasive carp-related data from all agencies exists. Invasive carp-related data include all data sources that could inform the MRWG objectives or projects. These data, often in disparate formats, must be integrated into a common format that allows all agencies the opportunity to assess invasive carp monitoring, control, and removal efforts. Ensuring the interoperability of these datasets allows for their use in various analyses and modeling efforts. Implementing an interoperable data management framework provides mechanisms for end-users to find and use integrated data. Integrating data for use in modeling and analysis furthers the partnership’s collective understanding of invasive carp life history, distribution, and movement and can be used to facilitate adaptive management actions (e.g., directing monitoring, sampling, and removal efforts, assessing invasive carp abundance to support modeling efforts, informing deployment of control actions, etc.). An effective data management strategy will streamline the data update process, providing all agencies with timely data and analyses in support of informed decisionmaking processes.

Interim Summary Report↗

Unique challenges facing Southwestern tribes: Chapter 17

Executive Summary When considering climate change, risks to Native American lands, people, and cultures are noteworthy. Impacts on Native lands and communities are anticipated to be both early and severe due to their location in marginal environments. Because Native American societies are socially, culturally, and politically unique, conventional climate change adaptation planning and related policies could result in unintended consequences or conflicts with Native American governments, or could prove to be inadequate if tribal consultation is not considered. Therefore, it is important to understand the distinct historical, legal, and economic contexts of the vulnerability and adaptive capacity of Southwestern Native American communities. The key messages presented in this chapter are: • Vulnerability of Southwestern tribes is higher than that for most groups because it is closely linked to endangered cultural practices, history, water rights, and socio-economic and political marginalization, characteristics that most Indigenous people share. (high confidence) • Very little data are available that quantify the changes that are occurring or that establish baseline conditions for many tribal communities. Additional data are crucial for understanding impacts on tribal lands for resource monitoring and scientific studies. (high confidence) • The scant data available indicate that at least some tribes may already be experiencing climate change impacts. (medium confidence) • Tribes are taking action to address climate change by instituting climate-change mitigation initiatives, including utility-scale, alternative-energy projects, and energy-conservation projects. Tribes are also evaluating their existing capacity to engage in effective adaptation planning, even though financial and social capital is limited.

Book chapter↗

USGS invasive carp database management and integration support

Invasive carp tracking, monitoring, and contracted removal will continue throughout the Illinois River and upper Mississippi River as part of an adaptive management effort to mitigate, control, and contain invasive carp. To facilitate these actions, a need to compile and analyze invasive carp-related data from all agencies exists. Invasive carp-related data include all data sources that could inform the MRWG objectives or projects. This data, often in disparate formats, must be integrated into a common format that allows all agencies the opportunity to assess invasive carp monitoring, control, and removal efforts. Ensuring the interoperability of these datasets allows for their use in various analyses and modeling efforts. Implementing an interoperable data management framework provides mechanisms for endusers to find and use integrated data. Integrating data for use in modeling and analysis furthers the partnership’s collective understanding of invasive carp life history, distribution, and movement and can be used to facilitate adaptive management actions (e.g., directing monitoring, sampling, and removal efforts; assessing invasive carp abundance to support modeling efforts; informing deployment of control actions; etc.). An effective data management strategy will streamline the data update process, providing all agencies with timely data and analyses in support of informed decision-making processes.

Interim Summary Report↗

Evaluation of Caspian tern ( Hydroprogne caspia ) and snowy plover ( Charadrius alexandrinus nivosus ) nesting on modified islands at the Don Edwards San Francisco Bay National Wildlife Refuge, California—2016 Annual Report

Executive Summary In order to address the 2008/10 and Supplemental 2014 NOAA 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 have begun 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 include (1) reducing nesting habitat for Caspian terns in the Columbia River estuary and the mid-Columbia River region, and (2) creating or modifying nesting habitat at alternative sites within the Caspian tern breeding range. 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, to reduce or eliminate potential conflicts between nesting Caspian terns and threatened western snowy plovers ( Charadrius alexandrinus nivosus), nesting habitat for snowy plovers also was developed. 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 between March and September of 2015 and 2016 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. The success of 2015 continued in 2016, the second year of the study. In 2016, Caspian terns nested on two of the five islands modified for Caspian terns (one island in Pond A16 and one island in Pond SF2). Caspian terns initiated at least 317 nests, fledged at least 158 chicks, and had a breeding success rate of 0.50 fledged chicks per breeding pair. This represents a 42 percent increase in nests initiated, a 9 percent decrease in the number of fledged chicks, and a 36 percent decrease in the number of chicks fledged per breeding pair in 2016 compared to 2015. Although overall productivity decreased from 2015, these results indicate that the Caspian tern breeding population on modified islands of the DENWR is increasing relative to 2015, the first year of the effort, and relative to years prior to 2015 when no breeding colonies of Caspian terns existed in Ponds A16 or SF2. These results indicate the effectiveness of social attraction measures in helping to establish tern nesting colonies in San Francisco Bay. Conversely, for the second year in a row, snowy plovers did not attempt to nest on any island in Ponds A16 and SF2. 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↗

Impacts of climate change on biodiversity, ecosystems, and ecosystem services: technical input to the 2013 National Climate Assessment

Ecosystems, and the biodiversity and services they support, are intrinsically dependent on climate. During the twentieth century, climate change has had documented impacts on ecological systems, and impacts are expected to increase as climate change continues and perhaps even accelerates. This technical input to the National Climate Assessment synthesizes our scientific understanding of the way climate change is affecting biodiversity, ecosystems, ecosystem services, and what strategies might be employed to decrease current and future risks. Building on past assessments of how climate change and other stressors are affecting ecosystems in the United States and around the world, we approach the subject from several different perspectives. First, we review the observed and projected impacts on biodiversity, with a focus on genes, species, and assemblages of species. Next, we examine how climate change is affecting ecosystem structural elements—such as biomass, architecture, and heterogeneity—and functions—specifically, as related to the fluxes of energy and matter. People experience climate change impacts on biodiversity and ecosystems as changes in ecosystem services; people depend on ecosystems for resources that are harvested, their role in regulating the movement of materials and disturbances, and their recreational, cultural, and aesthetic value. Thus, we review newly emerging research to determine how human activities and a changing climate are likely to alter the delivery of these ecosystem services. This technical input also examines two cross-cutting topics. First, we recognize that climate change is happening against the backdrop of a wide range of other environmental and anthropogenic stressors, many of which have caused dramatic ecosystem degradation already. This broader range of stressors interacts with climate change, and complicates our abilities to predict and manage the impacts on biodiversity, ecosystems, and the services they support. The second cross-cutting topic is the rapidly advancing field of climate adaptation, where there has been significant progress in developing the conceptual framework, planning approaches, and strategies for safeguarding biodiversity and other ecological resources. At the same time, ecosystem-based adaptation is becoming more prominent as a way to utilize ecosystem services to help human systems adapt to climate change. In this summary, we present key findings of the technical input, focusing on themes that can be found throughout the report. Thus, this summary takes a more integrated look at the question of how climate change is affecting our ecological resources, the implications for humans, and possible response strategies. This integrated approach better reflects the impacts of climate in the real world, where changes in ecosystem structure or function will alter the viability of different species and the efficacy of ecosystem services. Likewise, adaptation to climate change will simultaneously address a range of conservation goals. Case studies are used to illustrate this complete picture throughout the report; a snapshot of one case study, 2011 Las Conchas, New Mexico Fire , is included in this summary.

Report↗

USGS telemetry project

Tagging bigheaded carp (i.e., Bighead Carp and Silver Carp) and surrogate fish species with acoustic transmitters has become an invaluable management tool in the Upper IWW (i.e., upper Illinois River, lower Des Plaines River, and the CAWS). For example, movement probabilities between adjacent navigation pools need to be estimated to parameterize models, such as the SEICarP Model—a population model used in scenario planning by the MRWG to evaluate alternative management actions (Kallis et al. 2023). These movement probabilities are estimated from the telemetry data obtained from a longitudinal network of strategically placed receivers that detect bigheaded carp that have been implanted with acoustic transmitters (i.e., tagged). In addition, fish removal by contracted fishers has become the primary method of controlling bigheaded carp in the upper Illinois and lower Des Plaines rivers. Variable patterns in bigheaded carp distribution, habitat, and movement, influenced by seasonal and environmental conditions, make targeting bigheaded carp for removal and containment challenging and costly. Understanding these movement patterns for bigheaded carp through modeling and real-time telemetry applications informs removal efforts and facilitates monitoring and contingency actions based on fish movements.

Illinois↗

Vertical accretion versus elevational adjustment in UK saltmarshes: An evaluation of alternative methodologies

Simultaneous measurements of vertical accretion from marker horizons and marsh-elevation change from sedimentation-erosion tables (SET) were made in selected marshes along the East Anglian coast of the UK in order to address the following objectives: to ascertain the validity of treating accretion measurements obtained within tidally dominated, minerogenic saltmarshes as equivalent to surface elevation changes; to explore the implications, in terms of physical and biological processes, of discrepancies between separately measured vertical accretion and elevation change within contrasting marsh types. Data were collected from several marsh environments at Scolt Head Island and Stiffkey on the North Norfolk coast and at an experimental managed realignment project near Tollesbury, Essex. Scolt Head Island was selected for its long-term datasets of marsh accretion, Stiffkey for its contrasting open coast-back barrier settings, and Tollesbury for its experimental management, in order to illustrate the potential application of the SET method and evaluate the relationship between vertical accretion and elevation change in a variety of marsh settings. The relationship between vertical accretion and elevation change varied widely among marsh settings of different age and height (within the tidal frame) at Scolt Head Island and Stiffkey. Rates of vertical accretion and elevation change were similar in the older and mid-height settings on Scolt Head Island, indicating control of elevation change by surface accretionary processes (e.g. sediment deposition). However, subsurface processes controlled elevation at three of the marsh sites. Spartina Marsh, the youngest and lowest of the back barrier settings at Scolt Head Island, exhibited continuous shallow subsidence (vertical accretion greater than elevation change) over a 4-year period, implying that compaction controls elevation change. In the upper part of Hut Marsh and the interior of the Stiffkey marshes, elevation change exceeded vertical accretion suggesting that subsurface processes (e.g. organic accumulation) controlled elevation in these settings. Surface accretionary processes control elevation change in both the highly dynamic, outer marsh at Stiffkey and the low, restored marsh at Tollesbury. Despite the occurrence of shallow subsidence, all sites gained elevation at an annual rate comparable to that of sea-level rise. In summary, the SET provides the means to critically evaluate the influence of vertical accretion measures on elevation and represents an improved method by which to evaluate the vulnerability of a marsh to sea-level rise.

Scolt Head Island Marsh, Stiffkey Marsh, Tollesbur↗

U.S. Geological Survey Subsidence Interest Group conference, Edwards Air Force Base, Antelope Valley, California, November 18-19, 1992; Abstracts and summary

Land subsidence, the loss of surface elevation as a result of the removal of subsurface support, affects every state in the United States. More than 17,000 mi 2 of land in the United States has been lowered by the various processes that produce land subsidence with annual costs from resulting flooding and structural damage that exceed $125 million. It is estimated that an additional $400 million is spent nationwide in attempts to control subsidence. Common causes of land subsidence include the removal of oil, gas, and water from underground reservoirs; dissolution of limestone aquifers (sinkholes); underground mining activities; drainage of organic soils; and hydrocompaction (the initial wetting of dry soils). Overdrafting of aquifers is the major cause of areally extensive land subsidence, and as ground-water pumping increases, land subsidence also will increase. Land subsidence and its effects on engineering structures have been recognized for centuries, but it was not until this century that the processes that produce land subsidence were identified and understood. In 1928, while working with field data from a test of the Dakota Sandstone aquifer, O.E. Meinzer of the U.S. Geological Survey recognized the compressibility of aquifers. Around the same time, Karl Terzaghi, a soil scientist working at Harvard University, developed the one-dimensional consolidation theory that provided a quantitative means of predicting soil compaction resulting from the drainage of compressible soils. Thus, with the recognition of the compressibility of aquifers (Meinzer), and the development of a quantitative means of predicting soil compaction as a consequence of the reduction of intergranular pore pressure (Terzaghi), the theory of aquifer-system compaction was formed. With the widespread availability of electric power in rural areas, and the advent of the deep turbine pump, ground-water withdrawals increased dramatically throughout the country in the 1940's and 1950's. Along with this unprecedented increase in pumpage, substantial amounts of land subsidence were observed in several areas of the United States, most notably in Arizona, California, and Texas. Beginning in 1955, under the direction of Joseph Poland, the Geological Survey began the "Mechanics of Aquifers Project," which focused largely on the processes that resulted in land subsidence due to the withdrawal of ground water. This research team gained international renown as they advanced the scientific understanding of aquifer mechanics and land-subsidence theory. The results of field studies by members of this research group not only verified the validity of the application of Terzaghi's consolidation theory to compressible aquifers, but they also provided definitions, methods of quantification, and confirmation of the interrelation among hydraulic head declines, aquifer-system compaction, and land subsidence. In addition to conducting pioneering research, this group also formed a "center of expertise," providing a focal point within the Geological Survey for the dissemination of technology and scientific understanding in aquifer mechanics. However, when the "Mechanics of Aquifers Project" was phased out in 1984, the focal point for technology transfer no longer existed. Interest among various state and local agencies in land subsidence has persisted, and the Geological Survey has continued to participate in a broad spectrum of cooperative and Federally funded projects in aquifer mechanics and land subsidence. These projects are designed to identify and monitor areas with the potential for land subsidence, to conduct basic research in the processes that control land subsidence and the development of earth fissures, as well as to develop new quantitative tools to predict aquifer-system deformation. In 1989 an ad hoc "Aquifer Mechanics and Subsidence Interest Group" (referred to herein as the "Subsidence Interest Group") was formed

California↗

Water-resources-related information for the Milwaukee Metropolitan Sewerage District planning area, Wisconsin, 1970-2002

The Milwaukee Metropolitan Sewerage District (MMSD) Corridor Study is a three-phase project designed to improve the understanding of water resources in the stream corridors of the MMSD planning area by initially compiling existing data and using the compiled information to develop 3-year baseline and long-term monitoring plans. This report is one of the products of Phase I of the Corridor Study. A literature review of surface-water-quality, surface water- quantity, and ecology studies conducted from 1970 through 2001 was completed and is summarized in this report. An inventory of Geographic Information System spatial coverages available for the MMSD planning area has been assembled. A database of water, sediment, and tissue (fish, shellfish, and others) chemistry, macroinvertebrates, fish, algae, habitat, geomorphic, and other physical and ecological data was compiled from data sets from MMSD, U.S. Geological Survey, Wisconsin Department of Natural Resources, and the U.S. Environmental Protection Agency. More than 2.7 million results are available in the MMSD Corridor Study database and the compilation of multiple datasets allows for retrieving data from a central database rather than from each of the source datasets. Data for 1970 through 2002 were collected for the 420-square-mile planning area by various agencies using different field data-collection and laboratory analysis methods. Chemical constituents and ecological components that are important to an urban setting and well represented in the database were selected for further investigation. Each constituent or component is described in this report with some or all of the following: a text summary, map of sampling locations, and in some cases median concentrations, statistical distributions of concentrations by subwatershed, table of summary statistics by subwatershed, and graphs of temporal and (or) seasonal trends. Physical data presented in the report include streamflow, stream stage, and precipitation data. Chemical indicators of water quality presented in the report include field measurements and miscellaneous constituents (pH, alkalinity, specific conductance, hardness, dissolved oxygen, biochemical oxygen demand, and chloride), sediment (total suspended solids and suspended sediment), nutrients (total nitrogen, nitrate, Kjeldahl nitrogen, total phosphorus, and dissolved phosphorus), trace elements (cadmium, mercury, copper, lead, arsenic, chromium, nickel, and zinc), pesticides (historically used pesticides and pesticides still in use), and polychlorinated biphenyls. Ecological indicators of water quality discussed in the report include community surveys of macroinvertebrates and fish, chlorophyll a concentrations, habitat assessments and channel-measurement data, and fecal coliform and E. coli bacterial counts. In addition to the compilation of the database, a major purpose of this investigation was to identify additional sampling that should be conducted under the baseline monitoring phase, which will be the second phase of the Corridor Study. Additional sampling may include: • Some subwatersheds, such as those in the headwaters. • Emerging contaminants such as pharmaceuticals and personal care products (PPCPs), human hormones, organic wastewater contaminants, and other constituents that result from human activity. • E. coli, which can serve as an indicator of health risk to swimmers and other recreational water users. • Pesticides in all media. • PCBs. • Trace elements in water, bed sediment, and tissues (fish, shellfish, and others). • Samples during winter months or during early snowmelt episodes to address constituents such as chloride and some nutrients that have seasonal variability and that may be affected by factors such as road deicing during the winter. • Samples for macroinvertebrate and fish-community data and habitat assessments. • Physical data such as stream-channel cross-section profiles, bridge-scour assessments, flood-plain maps, structures, and shoreline conditions.

Wisconsin↗

U-Pb Zircon ages from bedrock samples collected in the Tanacross D-1, and parts of the D-2, C-1, and C-2 quadrangles, Alaska

This Alaska Division of Geological & Geophysical Surveys (DGGS) Preliminary Interpretive Report presents U-Pb ages of zircons from 14 sedimentary, metamorphic, and igneous samples collected during 2017 and 2018 field investigations in the northeastern Tanacross Quadrangle, Alaska. The DGGS Northeast Tanacross project is a part of multi-year effort to investigate the geology and mineral-resource potential of the Yukon-Tanana Uplands region in collaboration with the U.S. Geological Survey. The purpose of the U-Pb isotopic study is to better understand the Devonian-to-Mississippian and Mesozoic-to-Early Paleogene episodes of magmatic and tectonic events within the Yukon-Tanana Uplands and the relationship of magmatism to the metallic mineral deposits. This area is characterized by the presence of two Late Devonian to Mississippian metamorphic assemblages-Lake George and Fortymile River (Dusel-Bacon and others, 2006; Foster, 1970). Both assemblages are composed of metasedimentary and metavolcanic rocks that have been intruded by Devonian to Eocene intrusive rocks of varying composition and texture. Paleozoic intrusive rocks are deformed and metamorphosed and include prevalent Late Devonian-Early Mississippian augen orthogneiss, herein called the Divide Mountain suite, that was emplaced into and deformed together with the Lake George assemblage (Aleinikoff and others, 1986). The Fortymile River assemblage is primarily cross-cut by Mississippian to Permian intrusive rocks that are also pervasively deformed and metamorphosed. Following Jurassic to mid-Cretaceous regional metamorphism and deformation, all metamorphic rock packages were intruded by Mid- to Late-Cretaceous volcanic and plutonic rocks (Naibert and others, 2018), some of which have known or suspected potential for gold together with silver, zinc, copper, and lead mineralization. Products included in this data release are: A summary of sample-collection methods, the laboratory report, analytical data tables, and associated metadata. All components of this data release are available on the DGGS website http://doi.org/10.14509/30465 .

Alaska↗

Test holes drilled in support of ground-water investigations, Project Gnome, Eddy County, New Mexico

Project Gnome is a proposed underground nuclear shot to be detonated within a massive salt bed in Eddy County, N. Mex. Potable and neat potable ground water is present in rocks above the salt and is being studied in relation to this nuclear event. This report presents details of two test holes which were drilled to determine ground-water conditions in the near vicinity of the shot point. A well-defined aquifer is present at the site of USGS test hole 1, about 1,000 feet south of the access shaft to the underground shot point. Water with 75 feet of artesian pressure head is contained in the Culebra dolomite member of the Rustler formation. The dolomite aquifer is 32 feet thick and its top lies at a depth of 517 feet below land surface. The aquifer yielded 100 gpm (gallons per minute) with a drawdown of 40 feet during a pumping period of 24 hours. Water was not found in rocks above or below the Culebra dolomite. At the site of USGS test hole 2, about 2 miles southwest of the access shaft no distinctive aquifer exists. About one-half gpm was yielded to the well from the rocks between the Culebra dolomite and the top of the salt. Water could not be detected in the Culebra dolomite or overlying rocks. The report contains drawdown and recovery curves of yield tests, drilling-time charts, and electric logs. The data are given in tables; they include summaries of hole construction, sample description logs, water measurements, drilling-time logs, and water analyses.

Open-File Report↗

U.S.-Soviet Collaborative Geological and Geophysical Survey of the Mid-Atlantic Ridge near 31 degrees N, the Petrov Fracture Zone

Introduction In February 1989, the first formal U.S.-Soviet joint marine geologic-geophysical study in 10 years was undertaken along the Mid-Atlantic Ridge near 31°N on the 12th Cruise of the RN Akademik Boris Petrov of the Vernadsky Institute of Geochemistry (USSR Academy of Sciences, Moscow). This survey was initiated as part of the U.S.S.R.-U.S. cooperative research project "Mid-Atlantic Ridge Crest Processes" within the framework of the Soviet-U.S. bilateral Ocean Studies Agreement (Ostenso, 1989). U.S. scientists from the U.S. Geological Survey, University of Houston, and Woods Hole Oceanographic Institution participated in this program with Soviet scientists from the Vernadsky Institute of Geochemistry, Institute of Geology, and Schmidt Institute of Physics of the Earth, all institutes of the USSR Academy of Sciences in Moscow (Appendix 1 ). The ship departed from Rotterdam, Nederlands on February 2, 1989 and docked in Bridgetown, Barbados on February 28, 1989. A log of the ship's schedule during this cruise is given in Appendix 2. This study involved a limited multibeam-bathymetric, gravity, magnetic, and seismic- reflection survey. and dredging program of a short-offset transform fault named the Petrov Fracture Zone near 31 °N, located just north of the Atlantis Fracture Zone on the Mid Atlantic Ridge. A site survey at King's Trough in the northeast Atlantic for a MIR submersible program in June 1989 was originally planned as part of this program, but bad weather and the resultant poor quality geophysical data forced this work to be terminated after only one day. Nearly 6000 km of geophysical profile data and 13 dredge stations were completed during this cruise. A description of the geophysical systems aboard the RN Petrov is given in Appendices 3 and 4. All geophysical data were recorded on magnetic tape in data formats described in Appendix 5. Dredge locales and description summaries only are presented in Appendix 6. Detailed descriptions of dredge samples will be presented elsewhere. Operational plan for the studies on this cruise was developed as a cooperative effort between U.S. and Soviet scientists, who established jointly the basic objectives of the study. The U.S. scientists were given the responsibility for developing the detailed survey and dredge sampling plans. Dredge operations and basic geophysical systems operations were the responsibility of the Soviet personnel.

Open-File Report↗

Summary of climatic, geographic, geologic, and available hydrologic data and identification of data gaps for the Black Bear Creek watershed of the Pawnee Nation Tribal Jurisdictional Area, Oklahoma

The Pawnee Nation is compiling a comprehensive water-management plan for the Pawnee Nation Tribal Jurisdictional Area in north-central Oklahoma. One of the first steps needed in preparing such a plan is a summary and analysis of available hydrologic data and reports that have been published for the area. In phase I of a three-phase, watershed-based approach to summary and analysis of water resources of the Pawnee Nation, the U.S. Geological Survey, in cooperation with the Pawnee Nation and Bureau of Indian Affairs, conducted a literature search and data analysis for the Black Bear Creek watershed within the Pawnee Nation Tribal Jurisdictional Area, referred to herein as the “Black Bear Creek study area.” This report summarizes the available data for the Black Bear Creek study area. Climatic, geographic, geologic, water-use, and hydrologic data from previously published reports or databases were collected and analyzed for this report. Because of the limited amount of groundwater-quality data for the study area, a field collection of groundwater levels and water samples was conducted. Sixteen wells were identified, and groundwater levels were measured at each well. Eight wells were sampled, and water properties, major ions, and nutrients were measured. Overall, there are few long-term monitoring stations to help determine trends of surface-water quality, groundwater quality, and groundwater levels across the study area. Establishing and maintaining long-term streamflow, surface-water-quality, groundwater-level, and groundwater-quality monitoring sites would greatly increase the understanding of the water resources in the Black Bear Creek study area. Additionally, water-use estimates would be greatly improved by metering groundwater withdrawals. Establishing hydrologic and water-quality trends and having improved estimates of water use can aid decision makers in the stewardship of the water resources in this area. This report can aid the Pawnee Nation in prioritization of future projects and serve as a background document for the development of a jurisdiction-wide comprehensive water-management plan.

Oklahoma↗