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At least 649 records · Page 36Linked to original sources
USGS2009

Water Resources and Natural Gas Production from the Marcellus Shale

The Marcellus Shale is a sedimentary rock formation deposited over 350 million years ago in a shallow inland sea located in the eastern United States where the present-day Appalachian Mountains now stand (de Witt and others, 1993). This shale contains significant quantities of natural gas. New developments in drilling technology, along with higher wellhead prices, have made the Marcellus Shale an important natural gas resource. The Marcellus Shale extends from southern New York across Pennsylvania, and into western Maryland, West Virginia, and eastern Ohio (fig. 1). The production of commercial quantities of gas from this shale requires large volumes of water to drill and hydraulically fracture the rock. This water must be recovered from the well and disposed of before the gas can flow. Concerns about the availability of water supplies needed for gas production, and questions about wastewater disposal have been raised by water-resource agencies and citizens throughout the Marcellus Shale gas development region. This Fact Sheet explains the basics of Marcellus Shale gas production, with the intent of helping the reader better understand the framework of the water-resource questions and concerns.

Fact Sheet↗
USGS2010

Sustainability of natural attenuation of nitrate in agricultural aquifers

Increased concentrations of nitrate in groundwater in agricultural areas, coinciding with increased use of chemical and organic fertilizers, have raised concern because of risks to environmental and human health. At some sites, these problems are mitigated by natural attenuation of nitrate as a result of microbially mediated reactions. Results from U.S. Geological Survey (USGS) research under the National Water-Quality Assessment (NAWQA) program show that reactions of dissolved nitrate with solid aquifer minerals and organic carbon help lower nitrate concentrations in groundwater beneath agricultural fields. However, increased fluxes of nitrate cause ongoing depletion of the finite pool of solid reactants. Consumption of the solid reactants diminishes the capacity of the aquifer to remove nitrate, calling into question the long-term sustainability of these natural attenuation processes.

Fact Sheet↗
USGS2011

Understanding risk and resilience to natural hazards

Natural hazards threaten the safety and economic wellbeing of communities. These hazards include sudden-onset hazards, such as earthquakes, and slowly emerging, chronic hazards, such as those associated with climate change. To help public officials, emergency and other managers, the business community, and at-risk individuals reduce the risks posed by such hazards, the USGS Western Geographic Science Center is developing new ways to assess and communicate societal risk and resilience to catastrophic and chronic natural hazards.

Fact Sheet↗
USGS2012

Decision-support systems for natural-hazards and land-management issues

Scientists at the USGS Western Geographic Science Center are developing decision-support systems (DSSs) for natural-hazards and land-management issues. DSSs are interactive computer-based tools that use data and models to help identify and solve problems. These systems can provide crucial support to policymakers, planners, and communities for making better decisions about long-term natural hazards mitigation and land-use planning.

Fact Sheet↗
USGS2012

United States Geological Survey (USGS) Natural Hazards Response

The primary goal of U.S. Geological Survey (USGS) Natural Hazards Response is to ensure that the disaster response community has access to timely, accurate, and relevant geospatial products, imagery, and services during and after an emergency event. To accomplish this goal, products and services provided by the National Geospatial Program (NGP) and Land Remote Sensing (LRS) Program serve as a geospatial framework for mapping activities of the emergency response community. Post-event imagery and analysis can provide important and timely information about the extent and severity of an event. USGS Natural Hazards Response will also support the coordination of remotely sensed data acquisitions, image distribution, and authoritative geospatial information production as required for use in disaster preparedness, response, and recovery operations.

Fact Sheet↗
USGS2018

Hot water in the Long Valley Caldera—The benefits and hazards of this large natural resource

The volcanic processes that have shaped the Long Valley Caldera in eastern California have also created an abundant supply of natural hot water. This natural resource provides benefits to many users, including power generation at the Casa Diablo Geothermal Plant, warm water for a state fish hatchery, and beautiful scenic areas such as Hot Creek gorge for visitors. However, some features can be dangerous because of sudden and unpredictable changes in the location and flow rate of boiling water. The U.S. Geological Survey monitors several aspects of the hydrothermal system in the Long Valley Caldera including temperature, flow rate, and water chemistry.

California↗
USGS2019

Naturally occurring uranium in groundwater in northeastern Washington State

Uranium is a radioactive element (radionuclide) that occurs naturally in rock, soil, and water, usually in low concentrations. Radionuclides are unstable atoms with excess energy and as radionuclides decay, they emit radiation. The uranium decay sequence also includes other radionuclides of concern such as radium and radon. This fact sheet addresses naturally occurring uranium in groundwater in northeastern Washington.

Washington↗
USGS2020

Nature’s Notebook-A tool for recording the timing of seasonal activity of plants and animals

Nature's Notebook is a customizable program used by individual observers and Federal Government partners to document patterns in phenology—the timing of seasonal activity of plants and animals over the course of the calendar year. The USA National Phenology Network (USA-NPN) established Nature's Notebook in 2009 to create a standard approach for collecting phenology data on plants and animals across the country. Currently, about half of the data are submitted by independent backyard observers at individual sites and half are submitted by groups of participants as part of a Local Phenology Program. With support from the U.S. Geological Survey, the USA-NPN collects, organizes, and shares data on phenology. This information aids decision making, scientific discovery, and the development of a broader understanding of phenology.

Fact Sheet↗
USGS1996

The Importance of Reserve Growth to the Nation's Supply of Natural Gas

Experience shows that initial estimates of the size of newly discovered oil or gas fields are usually too low. As years pass, successive estimates of the ultimate recovery of fields tend to increase. The term "reserve growth" refers to the typical increases in estimated ultimate recovery that occur as oil or gas fields are developed and produced (Arrington, 1960; Attanasi and Root, 1994). An example for a particular field helps explain the nature of reserve growth. Figure 1 (63k GIF). shows ultimate recovery for a large natural-gas field in Texas as estimated in each year from 1977 through 1991. This gas field was discovered in the mid-1940's. In 1977, its ultimate recovery was estimated to be 2.1 trillion cubic feet of gas (tcfg). One might think that after some 30 years of development and production, the resource potential of a field would be well understood. However, by 1991 the estimated ultimate recovery of this field had increased to 3.1 tcfg. Reserve growth over the 15-year period totaled 1.0 tcfg and shows no signs of stopping.

Fact Sheet↗
USGS2003

Selected natural attenuation monitoring data, Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington, June 2001

Previous investigations have shown that natural attenuation and biodegradation of chlorinated volatile organic compounds (CVOCs) are substantial in shallow ground water beneath the 9-acre former landfill at Operable Unit 1 (OU 1), Naval Undersea Warfare Center (NUWC), Division Keyport, Washington. The U.S. Geological Survey (USGS) has continued to monitor ground-water geochemistry to assure that conditions remain favorable for contaminant biodegradation. This report presents the ground-water geochemical and selected CVOC data collected at OU 1 by the USGS during June 11-14, 2001 in support of the long-term monitoring for natural attenuation. Overall, the June 2001 data indicate that redox conditions in the upper aquifer remain favorable for reductive dechlorination of CVOCs because strongly reducing conditions persisted beneath much of the former landfill. Redox conditions in the intermediate aquifer down gradient of the landfill appear to have become more favorable for reductive dechlorination because June 2001 dissolved hydrogen concentrations indicated strongly reducing conditions there for the first time. Although changes in redox conditions were observed at certain wells during 2001, a longer monitoring period is needed to ascertain if phytoremediation activities are affecting the ground-water chemistry. A minor change to future monitoring is proposed. Filtered organic carbon (previously referred to as dissolved, and defined as that which passes through a 0.45-micrometer membrane filter) should be analyzed in the future rather than unfiltered (previously referred to as total) organic carbon because the filtered analysis may be a better measure of bioavailable organic carbon. Unfiltered and filtered organic carbon data were collected during June 2001 for comparison. Filtered organic carbon data collected in the future could be reasonably compared with historical unfiltered organic carbon data by multiplying the historical data by a factor of about 0.9.

Open-File Report↗
USGS2004

Selected natural attenuation monitoring data, Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington, June 2002

Previous investigations indicated that natural attenuation and biodegradation of chlorinated volatile organic compounds (CVOCs) are substantial in shallow ground water beneath the 9-acre former landfill at Operable Unit 1 (OU 1), Naval Undersea Warfare Center (NUWC), Division Keyport, Washington. The U.S. Geological Survey (USGS) has continued to monitor ground-water geochemistry to assure that conditions remain favorable for contaminant biodegradation. This report presents the geochemical and selected CVOC data for ground water at OU 1, collected by the USGS during June 10-14, 2002, in support of long-term monitoring for natural attenuation. Overall, the geochemical data for June 2002 indicate that redox conditions in the upper-aquifer water remain favorable for reductive dechlorination of chlorinated VOCs because strongly reducing conditions persisted beneath much of the former landfill. Redox conditions in the intermediate aquifer downgradient of the landfill also remained favorable for reductive dechlorination, although the 2002 dissolved hydrogen (H2) concentration from well MW1-28 is questionable. Changes in redox conditions were observed at certain wells during 2002, but a longer monitoring period and more thorough interpretation are needed to ascertain if phytoremediation activities are affecting redox conditions and if biodegradation processes are changing over time. The Navy intends to complete a more thorough interpretation in preparation for the 5-year review of OU 1 scheduled for 2004. There were a few substantial differences between the 2002 concentrations and previously observed concentrations of volatile organic compounds. Total CVOC concentrations in 2002 samples decreased substantially in all piezometers sampled in the northern plantation, and the largest percentages of decrease were for the compounds trichloroethene (TCE) and cis-1,2-dichloroethene (cis-DCE). Changes in total CVOC concentrations in the southern plantation were less consistent. Historically high concentrations were observed in samples from three piezometers, with particularly substantial increases in TCE and cis-DCE concentrations, and historically low concentrations were observed in two piezometers, with particularly substantial decreases in TCE and cis-DCE concentrations. Similarly to the redox chemistry, a longer monitoring period and more thorough interpretation are needed to ascertain if phytoremediation activities are affecting CVOC concentrations and if biodegradation processes are changing over time. No changes in monitoring plans are proposed for June 2003, although the practice of deploying a data sonde downhole while purging the wells will be discontinued. Downhole monitoring added uncertainty to selected measured dissolved H2 concentrations because of the possibility that the sonde and cable created a bridge that resulted in non-equilibrium dissolved H2 concentrations at the wells.

Open-File Report↗
USGS2004

Selected natural attenuation monitoring data, Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington, June 2003

Previous investigations have shown that natural attenuation and biodegradation of chlorinated volatile organic compounds (CVOCs) are substantial in shallow ground water beneath the 9-acre former landfill at Operable Unit 1 (OU 1), Naval Undersea Warfare Center (NUWC), Division Keyport, Washington. This report presents the ground-water geochemical and selected CVOC data collected at OU 1 by the U.S. Geological Survey (USGS) during June 17-20, 2003 in support of long-term monitoring for natural attenuation. Strongly reducing conditions favorable for reductive dechlorination of CVOCs were found in fewer upper-aquifer wells during June 2003 than were found during sampling periods in 2001 and 2002. Redox conditions in water from the intermediate aquifer just downgradient from the landfill remained somewhat favorable for reductive dechlorination. As was noted in previous monitoring reports, the changes in redox conditions observed at individual wells have not been consistent or substantial throughout either the upper or the intermediate aquifers. Compared to 2002 data, total CVOC concentrations in June 2003 were nearly unchanged in all northern plantation piezometers sampled, although the concentrations were historically low at two of those sites. Total CVOC concentrations decreased consistently in the southern plantation samples. Historically low total CVOC concentrations were observed in three of the piezometers sampled, and a two order-of-magnitude decrease in total CVOCs was observed at one of those sites. The observed decreases in CVOC concentrations appear to be in contrast with the 2003 redox data that suggested less favorable conditions for reductive dechlorination. The Navy and USGS plan to do more extensive data-collection and interpretation during 2004 to better understand and document possible changes in redox conditions and contaminant biodegradation.

Open-File Report↗
USGS2004

Conventional natural gas resource potential, Alaska North Slope

An estimate of total natural gas resource potential of northern Alaska can be obtained by summing known gas reserves in oil and gas fields (35 TCF), mean estimates of undiscovered nonassociated (61 TCF) and associated (12 TCF) gas resources in NPRA, and mean estimates of undiscovered nonassociated (4 TCF) and associated (5 TCF) gas resources in the 1002 area of ANWR; this yields a total of 117 TCF. When estimates of undiscovered gas resources for non-Federal lands are released in 2005, that total will increase by a non-trivial amount. Thus, the conventional natural gas resource potential of onshore and State offshore areas totals well over 100 TCF. The inclusion of the MMS mean estimate (96 TCF) for undiscovered gas resources in the Beaufort and Chukchi planning areas of the Federal offshore extends that total above 200 TCF.

Open-File Report↗
USGS2006

Selected Natural Attenuation Monitoring Data, Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington, June 2005

Previous investigations have shown that natural attenuation and biodegradation of chlorinated volatile organic compounds (VOCs) are substantial in shallow ground water beneath the 9-acre former landfill at Operable Unit 1 (OU-1), Naval Undersea Warfare Center, Division Keyport, Washington. The U.S. Geological Survey (USGS) has continued to monitor ground-water geochemistry to assure that conditions remain favorable for contaminant biodegradation. This report presents the ground-water geochemical and selected VOC data collected at OU-1 by the USGS during June 21-24, 2005, in support of long-term monitoring for natural attenuation. For June 2005, the strongly reducing conditions (sulfate reduction and methanogenesis) most favorable for reductive dechlorination of chlorinated VOCs were detected in fewer upper-aquifer wells than were detected during 2004. Redox conditions in ground water from the intermediate aquifer just downgradient of the landfill remained somewhat favorable for reductive dechlorination. Overall, the changes in redox conditions observed at individual wells have not been consistent or substantial throughout either the upper or the intermediate aquifers. In apparent contrast to changes in redox conditions, the chlorinated VOC concentrations were lower than previously measured in many of the piezometers in the northern phytoremediation plantation. The decrease in contaminant concentrations beneath the northern plantation and the end-product (ethane and ethene) evidence for reductive dechlorination are consistent with 2000-04 results. In the southern phytoremediation plantation, changes in chlorinated VOC concentrations were variable. Most notable was a substantial decrease in the sum of trichloroethene, cis-1,2-dichloroethene, and vinyl chloride concentrations at piezometer P1-9 from 75,000 to 1,000 micrograms per liter between 2004 and 2005. The high concentrations of the reductive dechlorination end-products ethane and ethene measured at the most contaminated sites (P1-6 and P1-7), as well as measurable concentrations at sites P1-9 and P1-10, are reliable evidence that reductive dechlorination of chlorinated VOCs is ongoing in the southern plantation. In the 10 passive-diffusion samplers deployed beneath the marsh stream, the highest chlorinated VOC concentrations measured were at a site (S-4) about midway along the sampled stream reach. In 2005, the sum of trichloroethene, cis-1,2-dichloroethene, and vinyl chloride concentrations increased nearly twofold in comparison to 2004. It is not certain that the apparent increase in concentrations is representative of site conditions. However, the chlorinated VOC concentrations have increased each time at the two most contaminated passive-diffusion sampler sites that have been sampled for multiple years. In the marsh stream, chlorinated VOC concentrations in surface water were low at the site (SW-S6) near the upgradient margin of the former landfill. Concentrations in the stream increased substantially after flowing past the southern phytoremediation plantation to the downstream site (MA-12). Overall, the 2005 data were consistent with previous findings of continued biodegradation of chlorinated VOCs in ground water, along with continued discharge of some chlorinated VOCs to surface water in the marsh stream.

Open-File Report↗
USGS2007

Selected Natural Attenuation Monitoring Data, Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington, June 2006

Previous investigations have shown that natural attenuation and biodegradation of chlorinated volatile organic compounds (VOCs) are substantial in shallow ground water beneath the 9-acre former landfill at Operable Unit 1 (OU 1), Naval Undersea Warfare Center, Division Keyport, Washington. The U.S. Geological Survey (USGS) has continued to monitor ground-water geochemistry to assure that conditions remain favorable for contaminant biodegradation. This report presents ground-water geochemical and selected VOC data collected at OU 1 by the USGS during June 12-14, 2006, in support of long-term monitoring for natural attenuation. For June 2006, the strongly reducing conditions (sulfate reduction and methanogenesis) most favorable for reductive dechlorination of VOCs were inferred for 5 of 15 upper-aquifer sites in the northern and southern phytoremediation plantations. Predominant redox conditions in ground water from the intermediate aquifer just downgradient from the landfill remained mildly reducing and somewhat favorable for reductive dechlorination. Since about 2003, measured dissolved hydrogen concentrations in the upper aquifer generally have been lower than those previously measured, although methane and sulfide have continued to be detected throughout the upper aquifer beneath the landfill. Overall, no widespread changes in ground-water redox conditions were measured that should result in either more or less efficient biodegradation of chlorinated VOCs. For the northern plantation in 2006, chlorinated VOC concentrations at piezometers P1-3 and P1-4 were lower than previously measured, and trichloroethene (TCE), cis-1,2-dichloroethene (cis-DCE), or vinyl chloride (VC) were not detected at piezometers P1-1 and P1-5. The steady decrease in contaminant concentrations and the continued detection of the reductive dechlorination end-products ethene and ethane have been consistent throughout the upper aquifer beneath the northern plantation. For the southern plantation in 2006, changes in chlorinated VOC concentrations at the piezometers were highly variable. At piezometer P1-9, the 2006 total chlorinated VOC concentration as well as the concentrations of cis-DCE and VC were measured at their highest levels to date; contaminant concentrations substantially decreased at piezometer P1-9 between June 2004 and June 2005. The reasons for the 2004-05 decrease in concentrations or the 2005-06 increase in concentrations are unknown. At piezometer P1-10, the consistent temporal trend of decreasing chlorinated VOC concentrations measured since 1999 ended, and the concentration of total chlorinated VOC in 2006 was the highest measured since 1999. The reductive dechlorination end-product ethene was measured at concentrations as high as 1,300 micrograms per liter in the upper aquifer beneath the southern plantation, which is reliable evidence that reductive dechlorination of VOCs is ongoing.

Open-File Report↗
USGS2008

Comments on potential geologic and seismic hazards affecting proposed liquefied natural gas site in Santa Monica Bay, California

In a letter to the U.S. Geological Survey (USGS) dated March 25, 2008, Representative Jane Harman (California 36th district) requested advice on geologic hazards that should be considered in the review of a proposed liquefied natural gas (LNG) facility off the California coast in Santa Monica Bay. In 2004, the USGS responded to a similar request from Representative Lois Capps, regarding two proposed LNG facilities offshore Ventura County, Calif., with a report summarizing potential geologic and seismic hazards (Ross and others, 2004). The proposed LNG Deepwater Port (DWP) facility includes single point moorings (SPMs) and 35 miles of underwater pipelines. The DWP submersible buoys, manifolds, and risers would be situated on the floor of the southern Santa Monica Basin, in 3,000 feet of water, about 23 miles offshore of the Palos Verdes Peninsula. Twin 24-inch diameter pipelines would extend northeastward from the buoys across the basin floor, up the basin slope and across the continental shelf, skirting north around the Santa Monica submarine canyon. Figure 1 provides locations of the project and geologic features. Acronyms are defined in table 1. This facility is being proposed in a region of known geologic hazards that arise from both the potential for strong earthquakes and geologic processes related to sediment transport and accumulation in the offshore environment. The probability of a damaging earthquake (considered here as magnitude 6.5 or greater) in the next 30 years within about 30 miles (50 km) of the proposed pipeline ranges from 16% at the pipeline's offshore end to 48% where it nears land (Petersen, 2008). Earthquakes of this magnitude are capable of producing strong shaking, surface fault offsets, liquefaction phenomena, landslides, underwater turbidity currents and debris flow avalanches, and tsunamis. As part of the DWP license application for the Woodside Natural Gas proposal in Santa Monica Bay (known as the OceanWay Secure Energy Project), Fugro West, Inc., had already prepared a document discussing geologic hazards in the area, titled 'Exhibit B Topic Report 6 - Geological Resources' (Fugro West, Inc., 2007); hereafter, this will be called the 'Geological Resources document'. The USGS agreed to evaluate the information in the Geological Resources document regarding (1) proximity of active faults to the proposed project, (2) potential magnitude of seismic events from nearby faults, (3) thoroughness of the assessment of earthquake hazards in general, (4) potential hazards from ground rupture and strong shaking, (5) potential hazards from tsunamis, and (6) other geologic hazards including landslides and debris flows. Because two new earthquake probability reports were scheduled to be released in mid-April, 2008, by the USGS and the California Geological Survey (CGS), the USGS suggested a 6-month review period to enable a thorough incorporation of this new information. Twenty-seven scientists from the USGS and the CGS reviewed various sections of the Geological Resources document. This report outlines our major conclusions. The appendix is a longer list of comments by these reviewers, grouped by section of the Geological Resources document. Before discussing our reviews, we first provide a brief overview of geologic hazards in the proposed site area. This report is a snapshot in time and any future work in the area will need to take into account ongoing research efforts. For example, USGS scientists collected seismic reflection data in the spring of 2008 to study the structure and seismic potential of several faults in the area. Their interpretations (Conrad and others, 2008a and 2008b) are too preliminary to be included in this report, but their final results, along with other researchers' studies in the project area, should be considered in any future work on the Deepwater Port project.

California↗
USGS2010

West Florida Shelf: A natural laboratory for the study of ocean acidificiation

Declining oceanic pH and carbonate-ion concentrations are well-known consequences of increased atmospheric and surface-ocean partial pressure of carbon dioxide (pCO2). The possible subject of shifts in seawater carbonate chemistry on biocalcification and survival rates of marine organisms provides questions amenable to both experimental and field study (Kleypas and Langdon, 2006). To date, limited quantitative data exist with which to formalize and test hypotheses regarding such impacts, particularly in continental-shelf settings. The continental shelves of Florida provide an ideal natural laboratory in which to test latitudinal (and temperature and depth) shifts in habitat ranges of calcifying organisms. Both the east and west Florida shelves extend from warm temperate to subtropical latitudes; additionally, the west Florida shelf has very little siliciclastic influx to mask the carbonate production. This study utilizes the natural laboratory of the west and southwest Florida shelf (fig 1.1) to examine the transition from foramol (predominately foraminifera and molluscan) carbonate sediments, characteristic of the west-central Florida shelf, to chlorozoan (algal and coral) sediments characteristic of the southwest Florida shelf. The west Florida shelf is a mixed siliciclastic carbonate ramp that to the south transitions to the carbonate-dominated southwest Florida shelf (Enos, 1977; Brooks and others, 2003). The west Florida shelf is a distally steepened carbonate ramp that is ~250 kilometers (km) wide (Read, 1985). It is covered by a veneer of unconsolidated sediment consisting of mainly biogenic carbonate and quartz in the near shore, with subordinate amounts of phosphate. The sediment-distribution pattern is largely a function of proximity to source, with physical processes playing a minor role in distribution. The carbonate sand-and-gravel fraction is produced by organisms within the depositional basin of the west Florida shelf (Brooks and others, 2003). The southwest Florida shelf is a rimmed carbonate margin where organisms produce virtually all of the substrate; it also exhibits a greater sediment thickness as compared to the west Florida shelf (Enos, 1977). Temperature, which is usually associated with latitude, plays a major role in locations of foramol versus chlorozoan assemblages, but other factors beyond latitude influence temperature on the west and southwest Florida shelves. The potential of cooler, deep-water upwelling and transport over the bottom waters of the shelf may have a significant role in the species assemblage at the sediment/water interface and ultimately on location of foramol versus chlorozoan production. Deep water transported onto and over the shelf may also have environmental ramifications beyond temperature by bringing in water of different chemistry.

Open-File Report↗
USGS2011

Reported historic asbestos mines, historic asbestos prospects, and other natural occurrences of asbestos in California

The map (Plate.pdf), pamphlet (Pamphlet.pdf), and the accompanying datasets in this report provide information for 290 sites in California where asbestos occurs in natural settings, using descriptions found in the geologic literature. Data on location, mineralogy, geology, and relevant literature for each asbestos site are provided. Using the map and digital data in this report, the user can examine the distribution of previously reported asbestos and their geological characteristics in California. This report is part of an ongoing study by the U.S. Geological Survey to identify and map sites where asbestos mineralization occurs in the United States, which includes similar maps and datasets of natural asbestos localities within the Eastern United States (http://pubs.usgs.gov/of/2005/1189/), the Central United States (http://pubs.usgs.gov/of/2006/1211/), the Rocky Mountain States (http://pubs.usgs.gov/of/2007/1182/), the Southwestern United States (http://pubs.usgs.gov/of/2008/1095/), and the Northwestern United States (Oregon and Washington) (http://pubs.usgs.gov/of/2010/1041/). These reports are intended to provide State and local government agencies and other stakeholders with geologic information on reported asbestos mineralization in the United States.

California↗