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USGS1984

Phosphate rock resources of the United States

In 1980, the United States produced about 54 million tons of phosphate rock, or about 40 percent of the world's production, of which a substantial amount was exported, both as phosphate rock and as chemical fertilizer. During the last decade, predictions have been made that easily ruinable, low-cost reserves of phosphate rock would be exhausted, and that by the end of this century, instead of being a major exporter of phosphate rock, the United States might become a net importer. Most analysts today, however, think that exports will indeed decline in the next one or two decades, but that resources of phosphate are sufficient to supply domestic needs for a long time into the future. What will happen in the future depends on the actual availability of low-cost phosphate rock reserves in the United States and in the world. A realistic understanding of future phosphate rock reserves is dependent on an accurate assessment, now, of national phosphate rock resources. Many different estimates of resources exist; none of them alike. The detailed analysis of past resource estimates presented in this report indicates that the estimates differ more in what is being estimated than in how much is thought to exist. The phosphate rock resource classification used herein is based on the two fundamental aspects of a mineral resource(l) the degree of certainty of existence and (2) the feasibility of economic recovery. The comparison of past estimates (including all available company data), combined with the writers' personal knowledge, indicates that 17 billion metric tons of identified, recoverable phosphate rock exist in the United States, of which about 7 billion metric tons are thought to be economic or marginally economic. The remaining 10 billion metric tons, mostly in the Northwestern phosphate district of Idaho, are considered to be subeconomic, ruinable when some increase in the price of phosphate occurs. More than 16 billion metric tons probably exist in the southeastern Coastal Plain phosphate province, principally in Florida and North Carolina and offshore in the shallow Atlantic Ocean from North Carolina to southern Florida. This resource is considered to be hypothetical because it is based on geologic inference combined with sparse drilling data. Total resources of phosphate rock in the United States are sufficient to supply domestic demands for the foreseeable future, provided that drilling is done to confirm hypothetical resources and the chemistry of the deposits is determined. Mining and beneficiation techniques will have to be modified or improved, and new techniques will have to be developed so that these deposits can be profitably exploited.

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USGS1983

Petroleum and mineral resources of Antarctica

No known petroleum or mineral resources occur in Antarctica. The data on these subjects have been collected, mainly since the IGY (International Geophysical Year), 1957-58, as a part of other research carried out by geologists and geophysicists from a number of countries. Specific resource-related studies have not been made. Wright and Williams (1974) summarized what was known of Antarctic mineral resources a decade ago. The U.S. Geological Survey has been actively pursuing various investigations in Antarctica since 194 7. In the course of this work and that of our colleagues elsewhere in the United States and in other countries, much information relevant to petroleum and mineral resources has been obtained. Since 1976, modern state-of-the-art multichannel seismic reflection and aeromagnetic surveys by several countries over the continental margin of Antarctica have indicated thick sedimentary basins. However, no offshore drilling beneath the continental shelf has taken place since the DSDP (Deep Sea Drilling Project) holes in the Ross Sea in 1973. Geologic field investigations begun at the turn of the twentieth century have been intensified in the past two decades; most rock outcrops have been visited and samples collected. Technology to exploit resources, particularly in the Arctic, has been developing at a rapid rate, and much of it could be applied to Antarctica. As a result of the petroleum price increases of the past decade, the attention of a number of countries has turned to Antarctica, but under the policy of "voluntary restraint" adopted by the Antarctic Treaty nations, no active petroleum or mineral exploration is taking place. The Antarctic treaty countries are in the process of negotiating an Antarctic mineral resources regime that is anticipated to be completed within the next several years. Therefore it seemed timely to us to readdress the question of petroleum and mineral resources. These reports review and summarize the available information. The first report summarizes the information relevant to petroleum resources. Although uneconomic at present, petroleum is generally considered more likely to be exploited (if supergiant fields were ever found) in the next few decades than hard minerals. The second report reviews the reported occurrences of minerals in Antarctica and discusses their significance. The final report discusses the Dufek layered mafic intrusion, second only to the Bushveld Complex in size in the world; the Dufek intrusion might be considered as a potential target for mineral exploration.

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USGS1987

Conference on Continental margin mass wasting and Pleistocene sea-level changes, August 13-15, 1980

A conference on Continental Margin Mass Wasting and Pleistocene Sea-Level Changes was held in Woods Hole, Mass., August 13-15, 1980. Forty-seven participants, representing many government, academic, and industrial organizations, discussed the current state of knowledge of the features of marine mass wasting and of the interrelations of factors influencing them. These factors include sediment source, composition, textures, sedimentation rates, climatic and sea-level changes, gas and gas hydrate (clathrate) contents of sediments, geotechnical characteristics, oceanographic and morphological factors, ground-water processes, and seismic events. The part played by these factors in the processes and features of mass movement and the engineering considerations imposed by the emplacement of manmade structures on the sea floor were considered vital to the evaluation of hazards involved in offshore exploration and development. The conference concluded with a call for bold programs to establish the probability of occurrence and the quantitative importance of these factors and to devise more reliable means of measurement, particularly in place, of the characteristics of the sediment and features involved.

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USGS1986

USGS research on energy resources, 1986; program and abstracts

The extended abstracts in this volume are summaries of the papers presented orally and as posters in the second V. E. McKelvey Forum on Mineral and Energy Resources, entitled "USGS Research on Energy Resources-1986." The Forum has been established to improve communication between the USGS and the earth science community by presenting the results of current USGS research on nonrenewable resources in a timely fashion and by providing an opportunity for individuals from other organizations to meet informally with USGS scientists and managers. It is our hope that the McKelvey Forum will help to make USGS programs more responsive to the needs of the earth science community, particularly the mining and petroleum industries, and Win foster closer cooperation between organizations and individuals. The Forum was named after former Director Vincent E. McKelvey in recognition of his lifelong contributions to research, development, and administration in mineral and energy resources, as a scientist, as Chief Geologist, and as Director of the U.S. Geological Survey. The Forum will be an annual event, and its subject matter will alternate between mineral and energy resources. We expect that the format will change somewhat from year to year as various approaches are tried, but its primary purpose will remain the same: to encourage direct communication between USGS scientists and the representatives of other earth-science related organizations. Energy programs of the USGS include oil and gas, coal, geothermal, uranium-thorium, and oil shale; work in these programs spans the national domain, including surveys of the offshore Exclusive Economic Zone. The topics selected for presentation at this McKelvey Forum represent an overview of the scientific breadth of USGS research on energy resources. They include aspects of petroleum occurrence in Eastern United States rift basins, the origin of magnetic anomalies over oil fields, accreted terranes and energy-resource implications, coal quality, geothermal energy sources, integrated geology and chemistry in uranium-deposit studies, and interpretations of sea-floor geology seen in reconnaissance-scale sidescan-sonar mosaics of the Gulf of Mexico and west coast Exclusive Economic Zone. Data are presented that are being used in building models of geothermal energy settings, basin histories, and the occurrence of energy resources. In addition to the technical sessions presenting the results of USGS research, each congressionally mandated USGS Mineral Resource Program has a display outlining plans and progress. We are all excited about this continuing opportunity to disseminate and discuss our research with our colleagues in industry and academia, and we welcome your suggestions on improving this series of Forums.

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USGS1986

Prospects for mineral resource assessments on public lands: Proceedings of the Leesburg workshop

Modern geological surveys pursue a wide spectrum of research activities in the earth sciences. From the beginning, however, one of the core tasks of any national geological survey has been the assessment and evaluation of its nation's mineral and fuel resources. The methods by which such assessments are carried out have become more sophisticated over time, in keeping with advancing geoscientific knowledge and the development and application of new concepts and technologies. However, the basic objectives of such work have changed little, and the fundamental goal remains the construction of the best possible base of information on the nature, distribution and economic potential of the resources within a nation's landmass and its offshore jurisdictions.

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USGS2016

Baseline coastal oblique aerial photographs collected from Navarre Beach, Florida, to Breton Island, Louisiana, September 18–19, 2015

The U.S. Geological Survey (USGS), as part of the National Assessment of Coastal Change Hazards project, conducts baseline and storm-response photography missions to document and understand the changes in vulnerability of the Nation's coasts to extreme storms. On September 18–19, 2015, the USGS conducted an oblique aerial photographic survey from Navarre Beach, Florida, to Breton Island, Louisiana, aboard a Maule MT57 (aircraft) at an altitude of 500 feet (ft) and approximately 1,200 ft offshore. This mission was conducted to collect baseline data for assessing incremental changes in the beach and nearshore area since the last survey, flown in September 2014 . The data can be used in the assessment of future coastal change. The photographs provided in this report are Joint Photographic Experts Group (JPEG) images. ExifTool was used to add the following to the header of each photograph: time of collection, Global Positioning System (GPS) latitude, GPS longitude, keywords, credit, artist (photographer), caption, copyright, and contact information. The photograph locations are an estimate of the position of the aircraft at the time the photograph was taken and do not indicate the location of any feature in the images (see the Navigation Data page). These photographs document the state of the barrier islands and other coastal features at the time of the survey. Pages containing thumbnail images of the photographs, referred to as contact sheets, were created in 5-minute segments of flight time. These segments can be found on the Photographs and Maps page. Photographs can be opened directly with any JPEG-compatible image viewer by clicking on a thumbnail on the contact sheet. In addition to the photographs, a Google Earth Keyhole Markup Language (KML) file is provided and can be used to view the images by clicking on the marker and then the thumbnail or the link below the thumbnail. The KML file was created using the photographic navigation files. This KML file can be found in the kml folder.

Alabama, Florida, Louisiana, Mississippi↗

USGS2017

Winter 2016, Part A—Coastal oblique aerial photographs collected from the South Carolina/North Carolina border to Assateague Island, Virginia, February 18–19, 2016

North Carolina, Virginia↗

USGS2017

Winter 2016, Part B—Coastal oblique aerial photographs collected from Assateague Island, Virginia, to Montauk Point, New York, March 8–9, 2016

Delaware, Maryland, New Jersey, New York, Virginia↗

USGS2017

Post-Hurricane Katrina coastal oblique aerial photographs collected from Panama City, Florida, to Lakeshore, Mississippi, and the Chandeleur Islands, Louisiana, August 31, 2005

The U.S. Geological Survey (USGS), as part of the National Assessment of Storm-Induced Coastal Change Hazards project, conducts baseline and storm-response photography missions to document and understand the changes in vulnerability of the Nation's coasts to extreme storms. On August 31, 2005, the USGS conducted an oblique aerial photographic survey from Panama City, Florida, to Lakeshore, Mississippi, and the Chandeleur Islands, Louisiana, aboard a Piper Navajo Chieftain aircraft at an altitude of 500 feet and approximately 1,000 feet offshore. This mission was flown to collect post-Hurricane Katrina data, which can be used to assess incremental changes in the beach and nearshore area and can be used to assess future coastal change. The photographs in this report are Joint Photographic Experts Group (JPEG) images. These photographs document the state of the barrier islands and other coastal features at the time of the survey.

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USGS2017

Baseline coastal oblique aerial photographs collected from Dauphin Island, Alabama, to Breton Island, Louisiana, June 9, 2011

The U.S. Geological Survey (USGS), as part of the National Assessment of Storm-Induced Coastal Change Hazards project, conducts baseline and storm-response photography missions to document and understand the changes in vulnerability of the Nation's coasts to extreme storms. On June 9, 2011, the USGS conducted an oblique aerial photographic survey from Dauphin Island, Alabama, to Breton Island, Louisiana, aboard a Beechcraft BE90 King Air (aircraft) at an altitude of 500 feet (ft) (152 meters (m)) and approximately 1,200 ft (366 m) offshore. This mission was conducted to collect baseline data for assessing incremental changes in the beach and nearshore area and can be used to assess future coastal change. The photographs in this report are Joint Photographic Experts Group (JPEG) images. These photographs document the state of the barrier islands and other coastal features at the time of the survey.

Alabama, Louisiana↗

USGS2017

Distribution of foraminifera in Chincoteague Bay and the marshes of Assateague Island and the adjacent vicinity, Maryland and Virginia

Scientists from the U.S. Geological Survey (USGS), St. Petersburg Coastal and Marine Science Center conducted a seasonal collection of estuarine, marsh, and sandy washover surface sediments from Chincoteague Bay, Tom’s Cove, and the surrounding Assateague Island and Delmarva Peninsula in March–April and October 2014, after Hurricane Sandy. Micropaleontology samples were collected as part of a complementary USGS Coastal and Marine Geology Program Sea-level and Storm Impacts on Estuarine Environments and Shorelines project study. For comparison with estuarine and overwash deposited foraminifera, a group of scientists from the USGS Woods Hole Coastal and Marine Science Center in Massachusetts collected samples offshore of Assateague Island on the inner continental shelf during a seafloor mapping study in the summer of 2014 and shipped select samples to the St. Petersburg Coastal and Marine Science Center. The micropaleontological subsamples analyzed for foraminifera at each site can be used to establish a foraminiferal baseline assemblage that takes into consideration the seasonal variability of the various species, regarding density and geographic extent, which are influenced by transient and stable environmental parameters. By understanding what parameters affect the various foraminiferal assemblages, researchers can delineate how alterations in salinity, temperature, or marsh-to-bay interactions, such as marsh erosion, might affect that assemblage.

Maryland, Virginia↗

USGS2018

Chirp subbottom profile data collected in 2015 from the northern Chandeleur Islands, Louisiana

As part of the Barrier Island Evolution Research project, scientists from the U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted a nearshore geophysical survey around the northern Chandeleur Islands, Louisiana, in September 2015. The objective of the project is to improve the understanding of barrier island geomorphic evolution, particularly storm-related depositional and erosional processes that shape the islands over annual to interannual time scales (1–5 years). Collecting geophysical data can help researchers identify relations between the geologic history of the islands and their present day morphology and sediment distribution. High-resolution geophysical data collected along this rapidly changing barrier island system can provide a unique time-series dataset to further the analyses and geomorphological interpretations of this and other coastal systems, improving our understanding of coastal response and evolution over medium-term time scales (months to years). Subbottom profile data were collected in September 2015 offshore of the northern Chandeleur Islands, during USGS Field Activity Number 2015-331-FA. Data products, including raw digital chirp subbottom data, processed subbottom profile images, survey trackline map, navigation files, geographic information system data files and formal Federal Geographic Data Committee metadata, and Field Activity Collection System and operation logs are available for download.

Louisiana↗

USGS2020

Population estimates for selected breeding seabirds at Kīlauea Point National Wildlife Refuge, Kauaʻi, in 2019

Kīlauea Point National Wildlife Refuge (KPNWR) is an important seabird breeding site located at the northeastern tip of Kauaʻi in the main Hawaiian Islands. Despite the regional significance of KPNWR as one of the most important breeding sites for red-tailed tropicbirds ( Phaethon rubricauda ), red-footed boobies ( Sula sula ), and wedge-tailed shearwaters ( Ardenna pacifica ) in the main Hawaiian Islands, robust and accurate population surveys have not been consistently conducted and recent information is lacking. In this study, we completed comprehensive population surveys for these three species during the 2019 breeding season. Using direct censusing methods (ground-searching, visual and photographic counts), we determined that 387 red-tailed tropicbird and 5,049 red-footed booby breeding pairs nested at KPNWR in 2019. Additionally, we performed surveys of aerially displaying tropicbirds to estimate a potential population of 30 white-tailed tropicbird ( Phaethon lepturus ) breeding pairs at KPNWR. Using a stratified-random plot-sampling method, we estimated that 20,998 wedge-tailed shearwater pairs nested at KPNWR in 2019. The breeding population size results in this study are greater than those reported in the past for KPNWR. We suggest that the red-tailed tropicbird breeding population has increased since the mid-2000s (when population estimates were last made), whereas red-footed booby numbers likely have remained similar and 2019 results show an increase from past estimates because of the more comprehensive methods used in this study. The results of these surveys provide current and accurate population sizes for these species that can serve as (1) benchmarks for future management and monitoring at KPNWR and (2) important components of population-level assessments of seabird vulnerability to potential offshore wind energy development in the main Hawaiian Islands.

Hawaii↗

USGS2005

Archive of digital Boomer seismic reflection data collected during USGS Cruise 94CCT02, south-central South Carolina coastal region, August 1994

In August of 1994, the U.S. Geological Survey, in cooperation with Coastal Carolina University, conducted marine geophysical surveys in numerous water bodies adjacent to the south-central South Carolina coastal region. Data were collected aboard the MS Coastal in the Ashley, North Edisto, Wadmalaw, Dawho, South Edisto, and Ashepoo Rivers; the Wappoo, North, Steamboat, Bohicket, and Toogoodoo Creeks; Charleston Harbor; Wadmalaw Sound; Fenwick Cut; and the Atlantic Ocean from offshore Isle of Palms to Kiawah Island. This report serves as an archive of unprocessed digital boomer seismic reflection data, trackline maps, navigation files, GIS information, observers' logbooks, Field Activity Collection System (FACS) logs, and FGDC metadata. Filtered and gained digital images of the seismic profiles are also provided. The archived trace data are in standard Society of Exploration Geophysicists (SEG) SEG-Y format (Barry and others, 1975) and may be downloaded and processed with commercial or public domain software such as Seismic Unix (SU). Example SU processing scripts and USGS software for viewing the SEG-Y files (Zihlman, 1992) are also provided.

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USGS1995

1995 National assessment of United States oil and gas resources; results, methodology, and supporting data

This report summarizes the results of a 3-year study of the oil and gas resources of the onshore and state waters of the United States by the U.S. Geological Survey. A parallel study of the Federal offshore is being conducted by the Minerals Management Service. Estimates are made of technically recoverable oil, including measured (proved) reserves, future additions to reserves in existing fields, and undiscovered resources. Estimates are also made of the technically recoverable conventional resources of natural gas in measured reserves, in anticipated growth of reserves in existing fields, and in undiscovered resources. Additionally, an assessment is made of recoverable resources in continuous-type (largely unconventional) accumulations in sandstones, shales, chalks, and coal beds.

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USGS2008

Sea-Floor Mapping and Benthic Habitat GIS for the Elwha River Delta Nearshore, Washington

From March 1531, 2005, more than 252 km (19.5 km2) of seafloor offshore of the Elwha River Delta in the central Strait of Juan de Fuca was mapped by the USGS Coastal and Marine Geology Program. The purpose of this nearshore mapping was to (1) obtain high resolution bathymetry and acoustic reflectance properties of the seabed, (2) examine and record geologic characteristics of the seafloor, and (3) construct maps of sea-floor geomorphology and habitat. Substrate distribution was characterized with video-supervised statistical classification of the sonar data. Substrate of the survey was dominated by mixed sand-gravel and sand. Numerous boulder reefs were observed west of the river mouth within Freshwater Bay, whereas the sea-floor immediately adjacent to the river mouth was dominated by sand.

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USGS1996

Digital map data, text, and graphical images in support of the 1995 National assessment of United States oil and gas resources

This CD-ROM contains files in support of the 1995 USGS National assessment of United States oil and gas resources (DDS-30), which was published separately and summarizes the results of a 3-year study of the oil and gas resources of the onshore and state waters of the United States. The study describes about 560 oil and gas plays in the United States--confirmed and hypothetical, conventional and unconventional. A parallel study of the Federal offshore is being conducted by the U.S. Minerals Management Service. This CD-ROM contains files in multiple formats, so that almost any computer user can import them into word processors and mapping software packages. No proprietary data are released on this CD-ROM. The complete text of DDS-30 is also available, as well as many figures. A companion CD-ROM (DDS-36) includes the tabular data, the programs, and the same text data, but none of the map data.

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USGS1996

Tabular data, text, and graphical images in support of the 1995 National assessment of United States oil and gas resources

This CD-ROM contains files in support of the 1995 USGS National assessment of United States oil and gas resources (DDS-30), which was published separately and summarizes the results of a 3-year study of the oil and gas resources of the onshore and state waters of the United States. The study describes about 560 oil and gas plays in the United States; confirmed and hypothetical, conventional and unconventional. A parallel study of the Federal offshore is being conducted by the U.S. Minerals Management Service. This CD-ROM contains files in multiple formats, so that almost any computer user can import them into word processors and spreadsheets. The tabular data include some tables not released in DDS-30. No proprietary data are released on this CD-ROM, but some tables of summary statistics from the proprietary files are provided. The complete text of DDS-30 is also available, as well as many figures. Also included are some of the programs used in the assessment, in source code and with supporting documentation. A companion CD-ROM (DDS-35) includes the map data and the same text data, but none of the tabular data or assessment programs.

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