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USGS2014

Guidelines for monitoring and adaptively managing restoration of Chinook salmon ( Oncorhynchus tshawytscha ) and steelhead ( O. mykiss ) on the Elwha River

As of January, 2014, the removal of the Elwha and Glines Canyon dams on the Elwha River, Washington, represents the largest dam decommissioning to date in the United States. Dam removal is the single largest step in meeting the goals of the Elwha River Ecosystem and Fisheries Restoration Act of 1992 (The Elwha Act) — full restoration of the Elwha River ecosystem and its native anadromous fisheries (Section 3(a)). However, there is uncertainty about project outcomes with regards to salmon populations, as well as what the ‘best’ management strategy is to fully restore each salmon stock. This uncertainty is due to the magnitude of the action, the large volumes of sediment expected to be released during dam removal, and the duration of the sediment impact period following dam removal. Our task is further complicated by the depleted state of the native salmonid populations remaining in the Elwha, including four federally listed species. This situation lends itself to a monitoring and adaptive management approach to resource management, which allows for flexibility in decision-making processes in the face of uncertain outcomes. The Elwha Monitoring and Adaptive Management (EMAM) guidelines presented in this document provide a framework for developing goals that define project success and for monitoring project implementation and responses, focused upon two federally listed salmon species — Puget Sound Chinook salmon (Oncorhynchus tshawytscha) and Puget Sound steelhead (O. mykiss). The framework also should serve as a guide to help managers adaptively manage fish restoration actions during and following dam removal. The document is organized into seven sections, including an introduction (Section 1), a description of the adaptive management approach (Section 2), suggested modifications to the existing restoration strategy developed in previous Elwha River restoration documents (section 3), specific descriptions of an adaptive management framework, including establishment of goals, performance indicators, and potential adaptive management responses to monitoring information (section 4), monitoring tools and methods for use in evaluating performance and project outcomes (section 5), and brief sections on data record keeping and reporting (Section 6) and an estimated budget (section 7). The purpose of the EMAM guidelines is to propose (1) refinement of existing goals established in previous documents (e.g., Ward et al. (2008), U.S. Department of the Interior, Department of Commerce, and Lower Elwha S’Klallam Tribe (1994)); (2) an adaptive management framework, (3) specific trigger values for relevant performance indicators that guide the adaptive management approach, (4) a specific monitoring strategy for evaluating outcomes of restoration activities; (5) a data management strategy, (6) information needed for adjusting goals when observations indicate conditions are different from anticipated. When taken together, our proposed adaptive management guidelines rely upon setting goals and objectives for each species of interest, which are monitored by relevant performance indicators and measurable trigger values that define success within each phase of the project. The guidelines themselves are arranged in a hierarchy for each species of interest. The levels of this hierarchy are goals, objectives, performance indicators, decision rules, triggers, and decisions (i.e., management/policy response). The monitoring and adaptive management approach provided is based on monitoring several categories of performance indicators, each containing associated ‘trigger’ values which, when met, alters restoration activities (e.g., hatchery releases and/or strategies) through four successive restoration phases. Performance indicators proposed in these EMAM guidelines are based upon Viable Salmon Population (VSP) metrics, including abundance, productivity, distribution, and diversity (McElhany et al. 2000). Trigger values for each performance indicator are developed for four different restoration phases: Preservation, Recolonization, Local Adaptation, and Viable Natural Population. These biologically-based phases each have a set of objectives that are based on resource management scenarios, including the dam removal project itself, which change largely based on the level of active management required and the degree, if any, of resource utilization. Thus, details of prescribed management actions for each phase are based upon different needs specific to that phase. The creation of biologically-based phases is one of the major differences between our proposed EMAM guidelines and previously presented plans for Elwha River Restoration Project management. Changed largely in response to the recommendations of the most recent of three Hatchery Scientific Review Group project reviews (HSRG 2012), the goal-oriented phases replaced the previous system of temporal changes centered around the decommissioning of the dams (i.e., before, during, and after dam removal). By focusing on outcomes associated with rebuilding salmon populations instead of an engineering schedule, the guidelines are more amenable to an adaptive management framework and the ability for management actions to influence outcomes, particularly in the periods during and following dam removal. Trigger values for each performance indicator were generally developed using existing data from the Elwha River watershed, the Puget Sound region, or other Pacific Northwest rivers (i.e., elsewhere in Washington State, Oregon, British Columbia) modified to be relevant for Chinook salmon and steelhead recovery in the Elwha River. By meeting all of the trigger value levels for all performance indicators for a set amount of time within a management phase, the guidelines call for moving to the next phase. This next phase has a new set of trigger values for the same performance indicators. For example, upon moving from the Preservation phase to the Recolonization phase, the trigger value for intrinsic potential increases. Intrinsic potential is a pre-defined estimate of the total extent of available habitat within a watershed for adult and juvenile fish, specific to the target species and is therefore a performance indicator of spatial distribution. By the final Viable Natural Population phase, the entire intrinsic potential of the watershed is being occupied by the species of interest. For those cases when a performance indicator is not exceeding the target value for a particular phase after a certain time period, the trigger values provided in this document, as well as a series of exogenous variables, are explored that may help explain why the performance indicator is not being met. These exogenous variables include variables that are not part of the suite of performance indicators, such as hatchery production, harvest, habitat, and ecosystem indicators. In these cases where the program is stuck in a particular recovery phase, the situation could be caused by the selection of inappropriate trigger values or unforeseen environmental conditions. If the former, adaptive management would call for existing monitoring data to be used for modifying trigger values to an appropriate level. If one of the exogenous variables is found to be preventing the program moving to the next phase, then appropriate changes to management would be advised. For each performance indicator and many of the exogenous variables, a set of monitoring tools were proposed. Data standards were also proposed for data generated by each monitoring tool. Data management, record keeping, and reporting of monitoring and adaptive management activities and results are also outlined. Management of data from the focused monitoring program and documenting the outcomes of trigger value evaluations and associated decisions from the adaptive management approach are key components of the EMAM guidelines. Without a clear history of data generated and adaptive management decisions taken by managers, the ability to learn through adaptive management breaks down. In addition to the long time period involved, another complication is the fact that the data will likely be collected by different federal and state agencies, tribal staff, and others. Having a system of reporting developed should help alleviate potential problems. The restoration of the migration route to spawning and rearing habitats upstream of the former Glines Canyon Dam represents a great opportunity for salmon on the Olympic Peninsula. By removing two aging structures, it will be possible for all 5 species of salmon and steelhead to return to wild stretches of the Elwha River and major floodplain habitat characterized by multiple channels, as well as significant portions of numerous tributaries. Measuring the progress of restoration, from the perspective of both salmon populations and the ecosystem upon which they depend, is a great test for a collaborative team of scientists. The normally challenging conditions of working in a steep gradient, high velocity wilderness river are exacerbated by the release of millions of cubic yards of sediment that had accumulated in the reservoirs. After the first two years of the dam decommissioning process, this release has changed the ecology of the river, estuary, and nearshore habitats downstream of the dams. Our goal in developing the guidelines described is to provide a roadmap for tracking what hopefully will become a successful outcome. If successfully implemented, this information should prove useful as others begin planning for the removal, alteration, or reconstruction of dams throughout North America and elsewhere, an inevitable outcome of an aging dam infrastructure.

Washington↗
USGS2019

Southern sea otter (Enhydra lutris nereis) population biology at Big Sur and Monterey, California --Investigating the consequences of resource abundance and anthropogenic stressors for sea otter recovery

The range of the southern sea otter ( Enhydra lutris nereis ) spans most of the central California coast from Half Moon Bay to Gaviota. Some coastal areas within this range are heavily developed and highly impacted by humans, while other areas are wild and largely pristine. Determining the relative importance of food resource abundance, environmental conditions, and anthropogenic increases in pathogens and pollutants to population change in sea otters is critical to understanding limitations to population growth. To investigate the causal links between the sluggish population growth of sea otters in central California and factors that could be driving variation in survival and reproduction, we designed a study to compare two distinct subpopulations—one in an area of low human impact (Big Sur) and one in an area of high human impact (Monterey). Between 2008 and 2011, the U.S. Geological Survey and collaborators conducted a telemetry-based study of sea otters at these two locations. The results of this study were not consistent with the hypothesis that sea otters adjacent to human population centers (Monterey) experience higher exposure to pollutants and pathogens than those in lower impacted areas (Big Sur). In fact, based on serological analysis, female sea otters from Big Sur showed higher exposure rates to Toxoplasma gondii than did female otters from Monterey, while domoic acid exposure appeared to be similar at both sites. Gene expression (specifically transcription) analysis did not indicate any consistent differences between the two populations that would have suggested a response to pathogen or toxin exposure, although there were temporal changes in gene transcription for sea otters at Big Sur following potential exposure to run-off from wildfires that occurred during the study. Together, these metrics suggest that variation in exposure to environmental stressors occurred, but patterns were not clearly attributable to differences in human population densities or land-use patterns. When compared to Monterey, sea otters in Big Sur spent more time feeding, had a higher degree of dietary specialization, were in poorer body condition, and had lower survival rates (both pups and adults). Together, these metrics suggest that otters at Big Sur had greater nutritional stress, consistent with lower per-capita resource abundance. Overall, study results indicate that density-dependent population regulation, mediated by per-capita resource abundance, is the most significant factor currently limiting population growth in the center part of the range. Additionally, spatial and temporal variation in environmental and anthropogenic stressors also can affect sea otter health, although patterns of variation are complex and are not simply a function of proximity to human populations. We also found that exposure to environmental stressors (either natural or anthropogenic in origin) often is associated with resource limitation. Finally, our results indicate that sea otter populations are structured at relatively small spatial scales, and the processes that regulate population abundance (including density-dependent resource abundance) also occur at these smaller, more local scales.

California↗
USGS2009

To burn or not to burn Oriental bittersweet: A fire manager’s conundrum

Oriental bittersweet ( Celastrus orbiculatus ) is a highly invasive liana (woody vine) that occurs throughout the Eastern United States. This twining plant can blanket and girdle adjacent vegetation, affecting succession and damaging trees. In areas where prescribed fire is a management tool, the response of Oriental bittersweet to fire needs to be quantified, rather than relying on anecdotal evidence. Currently, in areas already infested with this species, there are no strategies for prioritizing pre- or post-fire treatments on Oriental bittersweet. This largely results from a lack of understanding of the nature of post-fire resprouting by this species. Sprouting of bittersweet can at least double with fire and sprouts appear to respond to fire with an increase in growth rate (Pavlovic and Young pers. obs.). Beyond this basic need to understand the interaction between fire and Oriental bittersweet resprouting, we need to investigate how fire may interact with light, soil moisture, litter and other environmental factors to either increase or decrease abundance of this species. Finally, it is unknown how fire regimes influence the distribution of Oriental bittersweet on the landscape; thus we need to model the distribution of Oriental bittersweet in a fire impacted landscape. If we determine through our research that fire enhances the spread of this species, modification of fire suppression tactics and potential fire exclusion zones may be necessary. Thus we will be able to provide land managers throughout the Eastern US with data-driven decision support tools for more successful management of this species in fire dependent and invaded areas.

Indiana↗
USGS1994

An interactive code (NETPATH) for modeling NET geochemical reactions along a flow PATH, version 2.0

NETPATH is an interactive Fortran 77 computer program used to interpret net geochemical mass-balance reactions between an initial and final water along a hydrologic flow path. Alternatively, NETPATH computes the mixing proportions of two to five initial waters and net geochemical reactions that can account for the observed composition of a final water. The program utilizes previously defined chemical and isotopic data for waters from a hydrochemical system. For a set of mineral and (or) gas phases hypothesized to be the reactive phases in the system, NETPATH calculates the mass transfers in every possible combination of the selected phases that accounts for the observed changes in the selected chemical and (or) isotopic compositions observed along the flow path. The calculations are of use in interpreting geochemical reactions, mixing proportions, evaporation and (or) dilution of waters, and mineral mass transfer in the chemical and isotopic evolution of natural and environmental waters. Rayleigh distillation calculations are applied to each mass-balance model that satisfies the constraints to predict carbon, sulfur, nitrogen, and strontium isotopic compositions at the end point, including radiocarbon dating. DB is an interactive Fortran 77 computer program used to enter analytical data into NETPATH, and calculate the distribution of species in aqueous solution. This report describes the types of problems that can be solved, the methods used to solve problems, and the features available in the program to facilitate these solutions. Examples are presented to demonstrate most of the applications and features of NETPATH. The codes DB and NETPATH can be executed in the UNIX or DOS1 environment. This report replaces U.S. Geological Survey Water-Resources Investigations Report 91-4078, by Plummer and others, which described the original release of NETPATH, version 1.0 (dated December, 1991), and documents revisions and enhancements that are included in version 2.0. 1 The use of trade, brand or product names in this report is for identification purposes only and does not constitute endorsement by the U.S. Geological Survey.

Water-Resources Investigations Report↗
USGS1984

Surficial geology

Surficial materials are those at or near the Earth's surface. They constitute, by far, the largest and most used part of the ground around us. Areas not covered by surficial deposits--bare bedrock--form probably less than 5 percent of our land surface. Most surficial deposits are composed of poorly consolidated clay, silt, sand, or gravel-sized particles that are produced chiefly by erosion and are transported by and finally deposited by water, wind, or ice, but are also partly produced by the in-situ weathering of bedrock. The major genetic categories are shown on the map by various colors; the principal compositional types in each category are indicated by patterns. Colors, patterns, and letter symbols are given in the explanation which follows this summary description. Surficial deposits have characteristics important to our environment--water-bearing properties, mineral resources, and suitability as a natural foundation for buildings. They are also susceptible to flooding, erosion, ground subsidence, land slides, and earthquakes.

National Atlas of the United States of America↗
USGS1968

Water resources of the Mississippi Headwaters Watershed, North-central Minnesota

The Mississippi Headwaters watershed is a 7,608 square mile area in north-central Minnesota which includes all land drained by the Mississippi River above the Crow Wing River. From its source in Lake Itasca, 1,460 feet above mean sea level, the Mississippi River follows a semicircular 376 mile course to where it leaves the watershed at an altitude of 1,150 feet. The origin of the river is in glacial moraine. The river flows through end moraines and rolling till plains, across an extensive outwash plain occupied by large reservoir lakes, and finally across an extensive marshy plain which is the bed of an ancient glacial lake. Glacial deposits in the watershed include till, lenses of sand and gravel in till, outwash deposits of sand and gravel, and lake deposits of fine sand, silt, and clay. Beneath the glacial drift is an uneven surface of Precambrian bedrock. Bedrock consists of igneous intrusives and metamorphosed sedimentary formations. Water resources in the area are abundant. Lakes and streams occupy about 8 percent of the surface of the area. Ground-water supplies are available from glacial drift and from bedrock.

Minnesota↗
USGS1972

Geologic maps of the Descartes region of the Moon Apollo 16 pre-mission maps

The evolution of the Moon’s s urface shows three successive stages (Hartmann, 1970). The earliest , from the beginning of the decipherable record to the Imbrian P eriod, was dominated by frequent large -scale impacts which produced overlapping and interfering craters and g iant multi-ringed basin with ejecta blankets. The second stage , extending through most of the Imbrian to early Eratosthenian Periods , was characterized by volcanism, producing basalt flows of the maria an vari ed materials on the terrae . The final and longest stage , extending through the greater part of the Eratosthe n ian Period and the whole of the Copernican , was one of reduced geologic activity. Major modifications of the geologic structure by large impacts of volcanism occurring only locally, although changes by small-scale impact and mass wasting affected the entire surface. The De s cartes region, in the central highlands of the Moon about 500 km southeast of the center of the lunar disk, is dominated by features of the middle st a ge and contains a n exceptionally favorable site for their study.

IMAP↗
USGS1984

Evaluation of the ground-water resources of parts of Lancaster and Berks Counties, Pennsylvania

Secondary openings in bedrock are the avenues for virtually all ground-water flow in a 626-sqare-mile area in Lancaster and Berks Counties, Pennsylvania. The number, size, and interconnection of secondary openings are functions of lithology, depth, and topography. Ground water actively circulates to depths of 150 to 300 feet below land surface. Total average annual ground-water recharge for the area is 388 million gallons per day, most of which discharges to streams from local, unconfined flow systems. A digital ground-water flow model was developed to simulate unconfined flow under several different recharge and withdrawal scenarios. On the basis of lithologic and hydrologic differences, the modeled area was sub-divided into 22 hydrogeologic units. A finite-difference grid with rectangular blocks, each 2,015 by 2,332 feet, was used. The model was calibrated under steady-state and transient conditions. The steady-state calibration was used to determine hydraulic conductivities and stream leakage coefficients and the transient calibration was used to determine specific yields. The 22 hydrogeologic units fall into four general lithologies: Carbonate rocks, metamorphic rocks, Paleozoic sedimentary rocks, and Triassic sedimentary rocks. Average hydraulic conductivity ranges from about 8.8 feet per day in carbonate units to about .5 feet per day in metamorphic units. The Stonehenge Formation (limestone) has the greatest average hydraulic conductivity--85.2 feet per day in carbonate units to about 0.11 feet per day in the greatest gaining-strem leakage coefficient--16.81 feet per day. Specific yield ranges from 0.06 to 0.09 in carbonate units, and is 0.02 to 0.015, and 0.012 in metamorphic, Paleozoic sedimentary, and Triassic sedimentary units, respectively. Transient simulations were made to determine the effects of four different combinations of natural and artificial stresses. Natural aquifer conditions (no ground-water withdrawals) and actual aquifer conditions (current ground-water withdrawals) were simulated for two years under normal seasonal and hypothetical drought (60-percent reduction in winter-spring recharge) conditions. In October, 6 months after the hypothetical drought, simulated declines in water-table altitude due to the drought occurred everywhere and ranged from a median of 3.6 feet in carbonate units to 8.7 feet in carbonate units. Simulated base flows for five major streams were reduced by 33 to 51 percent during the hypothetical drought. Also in October, maximum simulated declines in water-table altitude due to ground-water withdrawls ranged from 33 feet in carbonate units to 79 feet in Triassic sedimentary units. Simulated base flows for five major streams were reduced by the amount of ground water withdrawn. Finally, again in October, maximum simulated declines in water-table altitude due to the combination of hypothetical drought and ground-water withdrawls ranged from 38 feet in carbonate units to 109 feet in Triassic sedimentary units. Due to aquifer dewatering, simulated declines were as much as 24 feet greater than the sum of the separate simulated declines that were caused by hypothetical drought and ground-water withdrawals. Some of the greatest simulated declines were in well fields, operated by three municipalities that experienced water-supply problems during the 1980-81 drought.

Water-Resources Investigations Report↗
USGS2000

Evidence for Paleocene dinosaurs in the Ojo Alamo Sandstone, San Juan Basin, New Mexico

Dinosaur fossils from the Ojo Alamo Sandstone, San Juan Basin, New Mexico, have been a puzzle to geologists for decades because other stratigraphic and paleontologic evidence indicates that this formation is Paleocene in age. The Paleocene age of the Ojo Alamo is based on the following evidence: (1) the lowermost part of the Nacimiento Formation, which conformably overlies and intertongues with the Ojo Alamo Sandstone in the Ojo Alamo type area in the southern part of the basin, contains Paleocene (Puercan) mammalian fossils; (2) plant megafossils collected from the Ojo Alamo indicate a Tertiary age for this rock unit; (3) pollen-productive rock samples collected from the Ojo Alamo at several localities in the basin have, without exception, yielded Paleocene-age palynomorph assemblages, and conversely, no Cretaceous pollen has ever been reported from Ojo Alamo rock samples. We report here the first discovery of Paleocene palynomorphs from Ojo Alamo Sandstone outcrops in the northern San Juan Basin. The pollen-producing rock samples were collected from a coaly, carbonaceous shale bed 12-m above the base of the Ojo Alamo and 3-m below the level of a large hadrosaur femur (1310-mm long and weighing about 130 kg) collected from this site. The bone was recovered from a cobble-to-boulder conglomeratic sandstone but shows no evidence of abrasion by erosion indicating almost instant burial after death of the animal and early mineralization of the femur. It is our opinion that this bone was not reworked from underlying Cretaceous strata. The data from the San Juan River site indicate that dinosaurs did not die out at the end of the Cretaceous in the San Juan Basin, but lived on for as much as a few hundred thousand years into the Paleocene before finally becoming extinct.

New Mexico↗
USGS2002

Petroleum systems of the Malay Basin Province, Malaysia

The offshore Malay Basin province is a Tertiary oil and gas province composed of a complex of half grabens that were filled by lacustrine shales and continental clastics.These deposits were overlain by clastics of a large delta system that covered the basin.Delta progradation was interupted by transgressions of the South China Sea to the southeast, which finally flooded the basin to form the Gulf of Thailand.Oil and gas from the Oligocene to Miocene lacustrine shales and Miocene deltaic coals is trapped primarily in anticlines formed by inversion of the half grabens during the late Miocene.Hydrocarbon reserves that have been discovered amount to 12 billion barrels of oil equivalent.The U.S. Geological Survey assessment of the estimated quantities of conventional oil, gas and condensate that have the potential to be added to reserves by the year 2025 for this province is 6.3 billion barrels of oil equivalent (BBOE) (U. S. Geological Survey World Energy Assessment Team, 2000).

Basin Province↗
USGS2013

Status of a reconnaissance field study of the Susitna basin, 2011

The Alaska Division of Geological & Geophysical Surveys (DGGS) and Alaska Division of Oil and Gas (DOG), in collaboration with the U.S. Geological Survey (USGS) performed reconnaissance field studies for ten days in late June 2011, in the Susitna basin, directly north of Cook Inlet, south-central Alaska (fig. 1). The purpose of our investigation was to reconnoiter outcrops in the basin and along its periphery to gather new information towards understanding the basin formation history and stratigraphy. This reconnaissance data represents the first step toward better understanding the basin’s hydrocarbon potential, a key component of DGGS’s multi-year In- State Gas Program. This program is focused on collecting baseline geologic information from potential frontier gas basins to encourage new exploration to help, in part, reduce the high cost of energy in rural Alaska. Our work represents the first season of this three-year project. Preliminary results from year two, a companion project within the Nenana and Tanana basins in interior Alaska, are described by Wartes and others (2013). DGGS plans to return to the Susitna basin for follow-up fieldwork during the third and final year of the program. The motivation for developing a better understanding of the Susitna basin stems from the recognition that the Susitna basin shares similar age coal-bearing strata with the adjacent, petroliferous Cook Inlet forearc basin (Barnes, 1966; Reed and Nelson, 1980) and with exhumed strata in the Matanuska Valley forearc basin (Trop and others, 2003) (figs. 1 and 2). Cook Inlet basin has eight producing oil fields, more than 25 producing gas fields, and likely contains many additional undiscovered oil and gas accumulations (LePain and others, in press). Most of the Cook Inlet gas is of microbial origin and apparently was sourced from abundant coalbeds of primarily Miocene age in the Tyonek, Beluga, and Sterling Formations (Claypool and others, 1980; Magoon, 1994). If the biogenic gas model for Cook Inlet is applicable to the Susitna basin, then the latter may be a viable source for Alaska Railbelt and rural energy needs. This brief overview report summarizes the reconnaissance field data collected in the Susitna basin during the first summer of the program. As the data are developed, this report will be followed by interpretive technical reports addressing the stratigraphy, reservoir quality, coal quality and gas potential, hydrocarbon seal integrity, subsurface structure, and uplift history of the basin and sub-basin margins.

Alaska↗
USGS1983

Petroleum potential of wilderness lands in the Western United States

In 1982-83, the U.S. Geological Survey (USGS) conducted an investigation of the oil and gas potential of the designated and proposed Wilderness Lands in the Western United States. The scope of this study was limited to the assessment of conventional recoverable petroleum resources occurring in the designated and proposed Wilderness Lands of the Western United States that are administered under four Federal agencies: Bureau of Land Management (BLM), U.S. Forest Service (USFS), National Park Service (NPS), and Fish and Wildlife Service (FWS). The total area of the study included approximately 74 million acres of Wilderness Lands in these 11 Western States: Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington, and Wyoming. The 74 million acres represent 31 percent of the total Federal lands within these 11 Western States. Approximately 49 percent of all the lands in these States are federally owned. The objective of this study was to assemble through various means all the available pertinent information that could be brought together within the USGS and integrate these data into a computer-based digital cartographic data system that was focused upon the single issue of reviewing the known geological and geophysical data to determine the geologic characteristics favorable or unfavorable for the occurrence of petroleum resources in these Wilderness Lands. In a joint effort in the USGS between the Geologic Division (GD) and the National Mapping Division (NMD) all of the mappable information used in this study was prepared and processed by using digital cartographic techniques. These include digitizing the location and boundaries of the Wilderness Lands; acreage calculations; the boundaries of the USGS petroleum provinces; and the geologic and tectonic boundaries within each petroleum province and State. In addition, searches were conducted on well data files which provided the locations and geologic information on over 5,000 wells drilled within or immediately adjacent to the Wilderness Lands. An analysis of all the geologic characteristics favorable or unfavorable for petroleum occurrence in conjunction with the geologic settings for the Wilderness Lands scattered within the framework of the petroleum provinces was performed by a team of geologists on each of the wilderness tracts. The geologic characteristics reviewed for each tract included the presence or absence of the following: adequate source beds and reservoir rocks; adequate trapping mechanisms; favorable thermal and maturation histories; presence of petroleum seeps or adjacent wells with shows or production; and the presence of favorable sedimentary rock sections underlying volcanic terrane or faulted and overthrust areas. A description of the geology and geologic framework is provided for each State along with an explanation of the interpretative geology and evaluation of the petroleum potential within the locale of each of the wilderness tracts. The assessment of the petroleum resources on the Wilderness Lands was completed in two separate stages. In the first stage the geologists evaluated the geological characteristics for the favorability or lack of favorability for the occurrence of oil and natural gas within each wilderness tract and assigned a qualitative rating for each tract's potential for the occurrence of recoverable oil and gas resources. In the second stage in evaluating the petroleum potential for the wilderness tracts, an effort was made to arrive at a quantitative assessment within the framework of the USGS's latest published resource estimates which are made on a province basis. The geologic characteristics evaluated for the favorability of petroleum occurrence within each of the clusters of wilderness tracts were the determining factors for the subjective assessments of the petroleum potential for each wilderness tract occurring within the respective basin or province. The quantitative resource assessments are subjectively determined as to the richness and potential of the wilderness tracts relative to the total petroleum potential for the respective petroleum province within which they occur. The results of the qualitative analysis of the petroleum potential of the Wilderness Lands are tabulated by total acreages for each wilderness tract as classified by its potential rating. These tabulations are made for the Wilderness Lands by petroleum province, by State, and for the total Wilderness Lands in the 11 Western States. A summary is provided of the petroleum potential by acreage for all the Wilderness Lands in the Western United States by State and for the total 11 States. At least 34 percent of the total acreage for Wilderness Lands, or approximately 25 million acres, may have the geologic characteristics necessary for the occurrence of petroleum resources in varying amounts (high, medium, and low potential). An additional 33 percent of the Wilderness Lands may have some limited potential where small sedimentary areas are mixed within igneous and metamorphic terranes, but are more likely to fall in the low to zero potential. Finally, 33 percent of the Wilderness Lands probably have no petroleum potential because they are located in terranes with predominantly igneous and (or) metamorphic rocks that are unfavorable for the occurrence of petroleum. The quantitative petroleum assessments for the Wilderness Lands in the Western United States represent a part of the total estimate of the remaining undiscovered oil and natural gas for the 38 petroleum provinces, as defined by Dolton and others in USGS Circular 860 in 1981, within which the Wilderness Lands occur. The undiscovered recoverable oil for the Wilderness Lands in the Western States is estimated to range from 0.555 to 1.490 billion barrels with a mean estimate of 0.834 billion barrels. The undiscovered recoverable natural gas is estimated to range from 5.536 to 16.639 trillion cubic feet with a mean estimate of 9. 729 trillion cubic feet. Each range corresponds to the 95 and 5 percent probabilities of more than the respective amounts. The estimates reported at the 95 percent and 5 percent probabilities and the mean estimates for oil and gas are summarized for the separate States and the aggregated totals. A series of printed maps, one for each Western State, accompanies this report (Miscellaneous Investigations Series Maps I-1537-I-1547, in press) and shows in color the location and qualitative petroleum potential of the Wilderness Lands studied, with BLM identification of tracts; the boundary locations of all major Federal and Indian lands; the boundaries and identification of the USGS petroleum provinces; and other base information. A pamphlet will accompany each State map describing the geology of the State and the local geology relative to the position of the wilderness tracts and their petroleum potential. These maps were compiled by using traditional cartographic techniques from digitally produced graphics and are published as separate sheets for each State at a scale of 1:1,000,000.

Circular↗
USGS2020

A probabilistic assessment of tephra-fall hazards at Hanford, Washington, from a future eruption of Mount St. Helens

Hanford, Washington (USA) is the construction site of a multi-billion-dollar high-level nuclear waste treatment facility. This site lies 200 kilometers (km) east of Mount St. Helens (MSH), the most active volcano in the contiguous United States. Tephra from a future MSH eruption could pose a hazard to the air intake and filtration systems at this plant. In this report, we present a probabilistic estimate of the amount of tephra that could fall, and the concentrations of airborne ash that could occur at the Hanford Site during a future eruption. Mount St. Helens has produced four large explosive eruptions in approximately the past 500 years, suggesting that its annual probability of eruption ( P 1 ) is roughly 4/500=0.008. Assuming that a large eruption occurs, we calculate the probability ( P 3|1 ) of a given fall deposit thickness or airborne concentration at Hanford by running about 10,000 simulations of ash-producing eruptions using the atmospheric transport model Ash3d. In each simulation, we calculate the pattern of tephra dispersal, deposit thickness at Hanford, and airborne ash concentration at ground level. As input for each simulation, we choose meteorological conditions from a randomly chosen time in the historical record between 1980 and 2010, using data from the European Centre for Medium-Range Weather Forecasting (ECMWF) Reanalysis (ERA) Interim model. The volume (dense-rock equivalent) of each simulated eruption is randomly chosen from a uniform probability distribution on a log scale from the range of magma volumes (0.008–2.3 cubic kilometers [km 3 ]) estimated for late Holocene eruptions at MSH. Plume heights and durations of each eruption are chosen using empirical correlations between volume, height, and eruption rate, which account for the fact that larger eruptions have higher plumes and last longer. We construct summary tables of final deposit thickness ( T ), maximum ground-level airborne concentration ( C max ), and average ground-level airborne concentration ( C avg ) during tephra-fall for each run. Each table is sorted and ranked by decreasing value of T , C max , or C avg . Conditional probabilities ( P 3|1 ) are derived by dividing rank by n+1, where n is the total number of successful runs. For example, a deposit thickness of 5.10 centimeters (cm) from run 446 is ranked 123 of 9,785 successful runs, yielding P 3|1 =123/9,786=0.01257. Its annual probability is P = P 1 · P 3|1 =0.008×0.01257=0.000101. By interpolation, the deposit thickness ( T 10k ) having an annual probability of 1 in 10,000 ( P = 0.0001) is 5.11 cm. Analogous concentration values are C max,10k =3,819 and C avg,10k =1,513 milligrams per cubic meter (mg/m 3 ), respectively. Independent calculations using the known mass accumulation rate of the deposit (=0.001–0.006 kilograms per square meter per second [kg/m 2 /s]), aggregate fall velocities ( u =0.3–0.8 meters per second [m/s]), and the simple formula , yield similar results, although highly variable fall velocities add significant uncertainty. This formula implies that deposit accumulation rates of millimeters (mm) to greater than 1 cm per hour, which are not uncommon during heavy ash fall, are associated with airborne concentrations of 10 2 –10 3 milligrams per cubic meter (mg/m 3 ). These concentrations are much higher than published measurements (10 -3 –10 1 mg/m 3 ), which record only suspended particles sampled in sheltered areas. During heavy ashfall, most fine ash falls as aggregates. Whether such aggregates will be ingested into air ducts will depend on the aggregate size and fall rate, the fragility of the aggregates, the air duct geometry, intake velocity, and other factors.

Washington↗
USGS1999

Observations at the Mars Pathfinder site: Do they provide "unequivocal" evidence of catastrophic flooding?

After Mars Pathfinder landed at the mouth of Ares Valus, a large channel that drains into the Chryse Planitia basin, the mission reports unanimously supported the interpretation that the lander site is the locus of catastrophic flooding by noting that all aspects of the scene are consistent with this interpretation. However, alternatives cannot be ruled out by any site observations, as all aspects of the scene are equally consistent with other interpretations of origin, namely, ice and mass-flow processes subsequently modified by wind erosion. The authors discuss alternative explanations for the geologic history of the channel based on a regional view of the circum-Chryse channels from Viking images (our best broad-scale information to date) and the local view from the recent Pathfinder landing site. Mega-indicators of channel origin, the regional geomorphology, geology, and planetary climatic conditions, taken together suggest some combination of flood, mass flow, glacial, and eolian processes. The macro-indicators of channel origin (sedimentologic) are also not indicative of one process of emplacement, either as single criteria or taken cumulatively. Finally, the micro-indicators of channel origin (geochemical and mineralogic composition) do not provide very tight constraints on the deposits' possible origins other than that water was in some way involved.

Journal of Geophysical Research E: Planets↗
USGS2003

Bisphenol A is released from used polycarbonate animal cages into water at room temperature

Bisphenol A (BPA) is a monomer with estrogenic activity that is used in the production of food packaging, dental sealants, polycarbonate plastic, and many other products. The monomer has previously been reported to hydrolyze and leach from these products under high heat and alkaline conditions, and the amount of leaching increases as a function of use. We examined whether new and used polycarbonate animal cages passively release bioactive levels of BPA into water at room temperature and neutral pH. Purified water was incubated at room temperature in new polycarbonate and polysulfone cages and used (discolored) polycarbonate cages, as well as control (glass and used polypropylene) containers. The resulting water samples were characterized with gas chromatography/mass spectrometry (GC/MS) and tested for estrogenic activity using an MCF-7 human breast cancer cell proliferation assay. Significant estrogenic activity, identifiable as BPA by GC/MS (up to 310 micro g/L), was released from used polycarbonate animal cages. Detectable levels of BPA were released from new polycarbonate cages (up to 0.3 micro g/L) as well as new polysulfone cages (1.5 micro g/L), whereas no BPA was detected in water incubated in glass and used polypropylene cages. Finally, BPA exposure as a result of being housed in used polycarbonate cages produced a 16% increase in uterine weight in prepubertal female mice relative to females housed in used polypropylene cages, although the difference was not statistically significant. Our findings suggest that laboratory animals maintained in polycarbonate and polysulfone cages are exposed to BPA via leaching, with exposure reaching the highest levels in old cages.

Environmental Health Perspectives↗
USGS2016

Regional chloride distribution in the Northern Atlantic Coastal Plain aquifer system from Long Island, New York, to North Carolina

The aquifers of the Northern Atlantic Coastal Plain are the principal source of water supply for the region’s nearly 20 million residents. Water quality and water levels in the aquifers, and maintenance of streamflow, are of concern because of the use of this natural resource for water supply and because of the possible effects of climate change and changes in land use on groundwater. The long-term sustainability of this natural resource is a concern at the local community scale, as well as at a regional scale, across state boundaries. In 2010, the U.S. Geological Survey (USGS) began a regional assessment of the Northern Atlantic Coastal Plain aquifers. An important part of this assessment is a regional interpretation of the extent of saltwater and the proximity of saltwater to fresh-groundwater resources and includes samples and published interpretations of chloride concentrations newly available since the last regional chloride assessment in 1989. This updated assessment also includes consideration of chloride samples and refined interpretations that stem from the 1994 discovery of the buried 35 million year old Chesapeake Bay impact structure that has substantially altered the understanding of the hydrogeologic framework and saltwater distribution in eastern Virginia. In this study, the regional area of concern for the chloride samples and interpretations extends from the Fall Line in the west to the outer edge of the Continental Shelf in the east and from the eastern tip of Long Island in the north to about halfway down the North Carolina coast in the south. Discussions of chloride distribution are presented for each of the 10 regional aquifer layers of the Northern Atlantic Coastal Plain, including the offshore extents. Maps of interpreted lines of equal concentration or isochlors were manually prepared for nine of the regional aquifers; a map was not prepared for the surficial regional aquifer. The isochlor interpretations include the offshore extent of the nine regional aquifers and are presented on a 1:2,000,000 scale base map. Vertically, the chloride samples and interpretations range from deepest (oldest) to shallowest (youngest)—Potomac-Patuxent, Potomac-Patapsco, Magothy, Matawan, Monmouth-Mount Laurel, Aquia, Piney Point, Lower Chesapeake, and Upper Chesapeake regional aquifers. The approach of this study maximizes the overall density of chloride information and data by assessing relevant published interpretations, all USGS chloride samples, and all relevant offshore samples in one comprehensive interpretation. Published isochlors, where they were interpreted by regional aquifer, were used as much as possible for this regional isochlor assessment. Publication dates for the isochlors used range from 1982 to 2015, and the scales for the isochlors range from local (county or municipality) to state (sub-regional) to regional. The USGS National Water Information System database provided well sample data for the parts of aquifers that are mainly beneath the land areas and yielded 37,517 water-quality records for 1903 through 2011. Published data reports from four phases of research-related offshore coring (1976, 1993, 1997, 2009) were the main source of water-quality data for the parts of aquifers from the shoreline to the outer edge of the Continental Shelf and yielded samples from multiple depths of each of 13 cores. This study also used interpretations and offshore core data from the last regional chloride assessment (1989) which, in addition to 7 offshore cores, included water-quality data from about 500 wells, and borehole geophysics interpretations from a subset of 11 wells. All published information and data that were used in this study were considered time independent and did not assess the published interpretations or data for temporal trends. The approach used here examined only published interpretations and available chloride data, and did not directly use supplemental techniques that can provide insight into the distribution of saltwater, such as geochemical characterization, borehole geophysical information, and geochronology. Isochlor maps for this study are limited to manual interpretations of the 250-milligram per liter (mg/L) and 10,000-mg/L boundaries developed for 9 of the 10 regional aquifers that constitute the regional hydrogeologic framework of the Northern Atlantic Coastal Plain. For a given aquifer, the approach was to initially consider published isochlor interpretations, where available, then to modify the published interpretations, if necessary, to the extent indicated by the well and core samples. The final step was to interpolate isochlors to the full extent of each aquifer layer in areas with sufficient samples or cited interpretations, or to extrapolate isochlors in areas with no samples or where samples were sparse. The principal limitation of this study is that, because of its regional extent, data and information density can vary greatly, and thus confidence in interpretations can vary widely for onshore and offshore areas across the study area. In areas of sparse data, some samples of elevated chloride could be misinterpreted as being part of a regional elevated chloride trend, and in other cases, an elevated concentration could be misinterpreted as being of only local importance. The interpretive work of this study was applied to a 1:2,000,000 scale base map. Locations of isochlors, wells, cores, political boundaries, and shorelines are meant to be considered approximate. The isochlors presented in this study were manually interpreted for each aquifer unit as a conceptual representation of an equal concentration line approximately in the middle of an aquifer’s thickness. Differences in chloride concentration lines between the top and bottom of an aquifer could be substantial, especially for the thick parts of aquifers, but that information is not presented in this regional assessment. Although additional offshore chloride data are available compared to 27 years ago (1989), the offshore information remains sparse, resulting in less confidence in the offshore interpretations than in the onshore interpretations. Regionally, the 250- and 10,000-mg/L isochlors tend to map progressively eastward from the deepest to the shallowest aquifers across the Northern Atlantic Coastal Plain aquifer system but with some exceptions. The additional data, conceptual understanding, and interpretations in the vicinity of the buried Chesapeake Bay impact structure in eastern Virginia resulted in substantial refinement of isochlors in that area. Overall, the interpretations in this study are updates of the previous regional study from 1989 but do not comprise major differences in interpretation and do not indicate regional movement of the freshwater-saltwater interface since then.

Delaware, Maryland, New Jersey, New York, North Ca↗
USGS1973

Stratigraphy and geologic history of the Montana group and equivalent rocks, Montana, Wyoming, and North and South Dakota

During Late Cretaceous time a broad north-trending epicontinental sea covered much of the western interior of North America and extended from the Gulf of Mexico to the Arctic Ocean. The sea was bounded on the west by a narrow, unstable, and constantly rising cordillera which extended from Central America to Alaska and which separated the sea from Pacific oceanic waters. The east margin of the sea was bounded by the low-lying stable platform of the central part of the United States. Rocks of the type Montana Group in Montana and equivalent rocks in adjacent States, which consist of eastward-pointing wedges of shallow-water marine and nonmarine strata that enclose westward-pointing wedges of fine-grained marine strata, were deposited in and marginal to this sea. These rocks range in age from middle Santonian to early Maestrichtian and represent a time span of about 14 million years. Twenty-nine distinctive ammonite zones, each with a time span of about half a million years, characterize the marine strata. Persistent beds of bentonite in the transgressive part of the Claggett and Bearpaw Shales of Montana and equivalent rocks elsewhere represent periods of explosive volcanism and perhaps concurrent subsidence along the west shore in the vicinity of the Elkhorn Mountains and the Deer Creek volcanic fields in Montana. Seaward retreat of st randlines, marked by deposition of the Telegraph Creek, Eagle, Judith River, and Fox Hills Formations in Montana and the Mesaverde Formation in Wyoming, may be attributed to uplift in near-coastal areas and to an increase in volcaniclastic rocks delivered to the sea. Rates of transgression and regression determined for the Montana Group in central Montana reveal that the strandline movement was more rapid during times of transgression. The regression of the Telegraph Creek and Eagle strandlines averaged about 50 miles per million years compared with a rate of about 95 miles per million years for the advance of the strand-line during Claggett time. The Judith River regression averaged about 60 miles per million years compared with movement of the strandline during the Bearpaw advance of about 70 miles per million years. The final retreat of marine waters from Montana, marked by the Fox Hills regression, was about 35 miles per million years at first, but near the end of the regression it accelerated to a rate of about 500 miles per million years. Rates of sedimentation range from less than 50 feet per million years in the eastern parts of North and South Dakota to at least 2,500 feet in western Wyoming. The low rates in the Dakotas correspond well with modern rates in the open ocean, and the rates in western Wyoming approach the rate of present coastal sedimentation.

Montana, North Dakota, South Dakota, Wyoming↗
USGS1987

Maps showing distribution of the Middle Cretaceous unconformity in the eastern Gulf of Mexico

Several theories on the origin of the Gulf of Mexico basin have been introduced by various researchers (Beloussov, 1970; Freeland and Dietz, 1971; Malfait and Dinkelman, 1972; Wood and Walper, 1974; Pilger, 1978; Buffler and others, 1980; Dickinson and Coney, 1980; Gose and others, 1980; Schmidt-Effing, 1980; Walper, 1980; Schlager and others, 1984). Although no final agreement has been reached, one prominent geologic feature is generally recognized. The early evolution of the basin ended with a major middle Cretaceous event resulting in a Gulf-wide unconformity referred to as the middle Cretaceous unconformity (MCU). This event represents a major shift from Early Cretaceous shallow-water bank sedimentation to Late Cretaceous deeper water carbonates (Worzel and others, 1973; Mitchum, 1978). Seismic data collected by the U.S. Geological Survey and the University of Texas Marine Science Institute, Galveston Geophysics Laboratory (UTMSI-GGL) were used to map the MCU and its relationship to the deep stratigraphy and structure of the eastern Gulf basin east of long 90° W. In addition, data from the Deep Sea Drilling Project (DSDP) in the southeastern Gulf and along the Campeche Escarpment and dredge samples collected by Schlager and others (1984) from the Florida Escarpment provide an age for the MCU (Cenomanian, 97 m. y. ) and a detailed lithological record. This report emphasizes the salt diapirs, pillows, and ridges in the northeastern Gulf of Mexico because of the profound effect these geologic structures have on the MCU. Salt locations are shown on the isopach of post-MCU sediments (fig. 1). A second map shows pre-middle Cretaceous outcrops terminated by the MCU along the Florida Escarpment, the southeastern Gulf, and the Campeche Escarpment (fig. 2).

Miscellaneous Field Studies Map↗