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USGS2023

Summary of the history and research of the U.S. Geological Survey gas hydrate properties laboratory in Menlo Park, California, active from 1993 to 2022

The U.S. Geological Survey (USGS) Clathrate Hydrate Properties Project, active from 1993 to 2022 in Menlo Park, California, stemmed from an earlier project on the properties of planetary ices supported by the National Aeronautics and Space Administration’s (NASA’s) Planetary Geology and Geophysics Program. We took a material science approach in both projects, emphasizing chemical purity of samples, having controlled grain size and grain texture, and having verified crystal structures and phase relations. A foundational contribution from our USGS Gas Hydrate Properties Laboratory (GHPL) was in demonstrating the ability to reproducibly create such pure clathrate hydrate samples for study. Clathrate sample synthesis was achieved by heating sieved and weighed pure granular water ice in the presence of cold clathrate-forming gas or liquid. During heating, the ice melts at the grain scale and reacts with the gas to form clathrate. The resulting material has the desired uniformity and purity, with known intergranular porosity; our subsequent measurements showed that these clathrates exhibited the established clathrate structures and phase relations. This novel synthesis method was successful in creating clathrates of pure methane, ethane, propane, carbon dioxide, and multi-component gases. By mixing sand or silt with granular ice, we were also able to make clathrate-sediment aggregates with controlled grain textures. This simple method, adopted by many others in the community, permitted us to measure the physical and chemical properties of well-characterized and well-crystallized clathrates and clathrate/sediment aggregates. At about the same time, we adapted conventional scanning electron microscopy to cryogenic conditions for analysis of grain-scale characteristics of clathrates made in the GHPL as well as those collected from nature by drill core. The uniformity and reproducibility of our samples also allowed us to investigate how clathrates respond to environmental changes in chemistry, temperature, and pressure: we measured chemical exchange rates with dissolved gas species—such as noble gases and chlorofluorocarbons—as well as rates of clathrate dissolution and decomposition. These advances include the first accurate mapping of the conditions that promote the remarkable process of “anomalous preservation” at room pressure, a metastability that offers potential application for low-cost and safe transportation of natural gas from gas fields far from pipelines. Another advancement stemming from the GHPL was the compaction of as-synthesized porous clathrates to nearly full density by applying external pressure using three different techniques. Compaction allows for high-accuracy measurements of many fundamental physical and chemical properties of these materials, such as elastic wavespeeds and moduli, complete thermal properties, decomposition rates, thermal expansion, and clathrate equations of state. These properties and others, in turn, have helped USGS scientists to interpret geophysical well logs and active geophysical surveys, as well as model the rates of gas production from hydrate deposits in nature. Studying this class of icy minerals that occur in abundance on Earth and in the outer solar system has been a fascinating laboratory journey. Here, we summarize the history and major findings of the USGS GHPL in Menlo Park, including both in-house research as well as findings from the synergistic collaborations with other agencies and institutes that were key to the success of our laboratory. The Menlo Park GHPL was more formally incorporated within the USGS Gas Hydrates Project, a collaboration among multiple USGS Science Centers, in the early 2000s under the leadership of Deborah Hutchinson, and now under the leadership of Carolyn Ruppel and Timothy Collett.

Open-File Report↗

USGS2011

A working environment for digital planetary data processing and mapping using ISIS and GRASS GIS

Since the beginning of planetary exploration, mapping has been fundamental to summarize observations returned by scientific missions. Sensor-based mapping has been used to highlight specific features from the planetary surfaces by means of processing. Interpretative mapping makes use of instrumental observations to produce thematic maps that summarize observations of actual data into a specific theme. Geologic maps, for example, are thematic interpretative maps that focus on the representation of materials and processes and their relative timing. The advancements in technology of the last 30 years have allowed us to develop specialized systems where the mapping process can be made entirely in the digital domain. The spread of networked computers on a global scale allowed the rapid propagation of software and digital data such that every researcher can now access digital mapping facilities on his desktop. The efforts to maintain planetary missions data accessible to the scientific community have led to the creation of standardized digital archives that facilitate the access to different datasets by software capable of processing these data from the raw level to the map projected one. Geographic Information Systems (GIS) have been developed to optimize the storage, the analysis, and the retrieval of spatially referenced Earth based environmental geodata; since the last decade these computer programs have become popular among the planetary science community, and recent mission data start to be distributed in formats compatible with these systems. Among all the systems developed for the analysis of planetary and spatially referenced data, we have created a working environment combining two software suites that have similar characteristics in their modular design, their development history, their policy of distribution and their support system. The first, the Integrated Software for Imagers and Spectrometers (ISIS) developed by the United States Geological Survey, represents the state of the art for processing planetary remote sensing data, from the raw unprocessed state to the map projected product. The second, the Geographic Resources Analysis Support System (GRASS) is a Geographic Information System developed by an international team of developers, and one of the core projects promoted by the Open Source Geospatial Foundation (OSGeo). We have worked on enabling the combined use of these software systems throughout the set-up of a common user interface, the unification of the cartographic reference system nomenclature and the minimization of data conversion. Both software packages are distributed with free open source licenses, as well as the source code, scripts and configuration files hereafter presented. In this paper we describe our work done to merge these working environments into a common one, where the user benefits from functionalities of both systems without the need to switch or transfer data from one software suite to the other one. Thereafter we provide an example of its usage in the handling of planetary data and the crafting of a digital geologic map. ?? 2010 Elsevier Ltd. All rights reserved.

Conference Paper↗

USGS2020

A synthesis of patterns of environmental mercury inputs, exposure and effects in New York State

Mercury (Hg) pollution is an environmental problem that adversely affects human and ecosystem health at local, regional, and global scales—including within New York State. More than two-thirds of the Hg currently released to the environment originates, either directly or indirectly, from human activities. Since the early 1800s, global atmospheric Hg concentrations have increased by three- to eight-fold over natural levels. In the U.S., atmospheric emissions and point-source releases to waterways increased following industrialization into the mid-1980s. Since then, water discharges have largely been curtailed. As a result, Hg emissions, atmospheric concentrations, and deposition over the past few decades have declined across the eastern U.S. Despite these decreases, Hg pollution persists. To inform policy efforts and to advance public understanding, the New York State Energy Research and Development Authority (NYSERDA) sponsored a scientific synthesis of information on Hg in New York State. This effort includes 23 papers focused on Hg in atmospheric deposition, water, fish, and wildlife published in Ecotoxicology . New York State experiences Hg contamination largely due to atmospheric deposition. Some landscapes are inherently sensitive to Hg inputs driven by the transport of inorganic Hg to zones of methylation, the conversion of inorganic Hg to methylmercury, and the bioaccumulation and biomagnification along food webs. Mercury concentrations exceed human and ecological risk thresholds in many areas of New York State, particularly the Adirondacks, Catskills, and parts of Long Island. Mercury concentrations in some biota have declined in the Eastern Great Lakes Lowlands and the Northeastern Highlands over the last four decades, concurrent with decreases in water releases and air emissions from regional and U.S. sources. However, widespread changes have not occurred in other ecoregions of New York State. While the timing and magnitude of the response of Hg levels in biota varies, policies expected to further diminish Hg emissions should continue to decrease Hg concentrations in food webs, yielding benefits to the fish, wildlife, and people of New York State. Anticipated improvements in the Hg status of aquatic ecosystems are likely to be greatest for inland surface waters and should be roughly proportional to declines in atmospheric Hg deposition. Efforts that advance recovery from Hg pollution in recent years have yielded significant progress, but Hg remains a pollutant of concern. Indeed, due to this extensive compilation of Hg observations in biota, it appears that the extent and intensity of the contamination on the New York landscape and waterscape is greater than previously recognized. Understanding the extent of Hg contamination and recovery following decreases in atmospheric Hg deposition will require further study, underscoring the need to continue existing monitoring efforts.

New York↗

USGS2019

Mapping research on hydropower and sustainability in the Brazilian Amazon: Advances, gaps in knowledge and future directions

In the last twenty years, multiple large and small hydroelectric dams have begun to transform the Amazonian region, spawning a growing volume of academic research across diverse disciplinary and interdisciplinary fields. In this article, we offer a critical review of recent research related to hydropower and sustainability with a focus on the Brazilian Amazon. We revisit the sustainability concept to include the contribution of various knowledge fields and perspectives for understanding, managing and making decisions about social-ecological systems transformed by dams. We conducted a literature review in Web of Science of academic publications centered in the past 5 years (2014–2019), on diverse aspects of hydropower planning, construction, operation and monitoring in the Brazilian Amazon. We present results of a co-occurrence network analysis of publications, highlighting bridging fields, network disconnections, and opportunities for interdisciplinary research. Finally, we report recent advances in the understanding and management of social-ecological systems in Amazonian watersheds, including biophysical, socio-economic, governance and development processes linked to hydropower planning and implementation. This review identifies knowledge gaps and future research directions, highlighting opportunities for improved communication among scientists, practitioners, decision-makers, indigenous peoples and local communities.

Amazon↗

USGS2009

A case of timely satellite image acquisitions in support of coastal emergency environmental response management

The synergistic application of optical and radar satellite imagery improves emergency response and advance coastal monitoring from the realm of “opportunistic” to that of “strategic.” As illustrated by the Hurricane Ike example, synthetic aperture radar imaging capabilities are clearly applicable for emergency response operations, but they are also relevant to emergency environmental management. Integrated with optical monitoring, the nearly real-time availability of synthetic aperture radar provides superior consistency in status and trends monitoring and enhanced information concerning causal forces of change that are critical to coastal resource sustainability, including flooding extent, depth, and frequency.

Journal of Coastal Research↗

USGS2026

Statistical facilitation in environmental science: Integrating results from complementary statistical analyses can improve ecological interpretations

Professionals working in biological conservation seek to understand, manage, and restore populations of native organisms using many techniques. A common approach for this discipline is using long-term data collections to inform decision making. However, several quantitative issues complicate statistical analysis of monitoring datasets and can reduce the utility of results for conservation decision making. Integrating results from multiple analyses applied to the same dataset (i.e., approaching the same biological problem using different techniques) is one way to address concerns related to field data that violate statistical assumptions. This process allows data analysts, researchers, and managers to assemble insights based on the weight of evidence. Here we tested whether three different statistical techniques [(1) multiple logistic regression on original data, (2) multiple logistic regression on standardized data (i.e., mean of 0 and standard deviation of 1), and (3) random forest analysis] identified a similar hierarchy for selecting natural and anthropogenic habitat regressors. Our examination of how environmental variables affected Plains Minnow ( Hybognathus placitus ), a state-threatened fish, is relevant to other taxa and locations. We gained useful information from redundancies (i.e., agreements across analyses). New directions also emerged by addressing ambiguities (i.e., disagreements among results across analyses). When multiple analyses were integrated into one ecological story, a clearer interpretation emerged. Viewing different statistical tests as facilitators that provide mutual advantages can advance the understanding and application of statistical analyses applied to non-experimental field datasets.

Kansas↗

USGS2022

Virtual special issue of recent advances on gas hydrates scientific drilling in Alaska

Gas hydrate refers to a non-stoichiometric clathrate that forms spontaneously in the natural environment whenever sufficient quantities of gases of appropriate size (most commonly methane) interact with abundant water under specific conditions of temperature and pressure. (1,2) Such conditions occur wherever the shallow geothermal gradient has been suppressed by either deepwater or thick permafrost, allowing for relatively low temperatures to coexist with elevated pressures. The volume of gas hydrate on Earth is difficult to constrain, (3) but it is sufficient that gas hydrate is a meaningful potential component of (1) the long-term natural cycling of carbon, (2) the nearer term environmental changes in response to warming climates, (4) and (3) future energy supply systems. Since the initial recognition of gas hydrate as an abundant component in nature in the late 1960s, a series of scientific drilling expeditions conducted by both the Integrated Ocean Discovery Program (and successors) and national research and development programs in Canada, Japan, China, the United States, South Korea, and others (5) have explored the occurrence and nature of gas hydrates. In particular, the desire for expanded energy supply options to support the economic development and energy security for nations around the globe is currently motivating a broad range of laboratory and numerical simulation studies in support of an ongoing series of field-based scientific tests of the potential commercial viability of gas extraction from natural gas hydrate deposits. (6)

Journal of Energy & Fuels↗

USGS2017

Widespread legacy brine contamination from oil production reduces survival of chorus frog larvae

Advances in drilling techniques have facilitated a rapid increase in hydrocarbon extraction from energy shales, including the Williston Basin in central North America. This area overlaps with the Prairie Pothole Region, a region densely populated with wetlands that provide numerous ecosystem services. Historical (legacy) disposal practices often released saline co-produced waters (brines) with high chloride concentrations, affecting wetland water quality directly or persisting in sediments. Despite the potential threat of brine contamination to aquatic habitats, there has been little research into its ecological effects. We capitalized on a gradient of legacy brine-contaminated wetlands in northeast Montana to conduct laboratory experiments to assess variation in survival of larval Boreal Chorus Frogs ( Pseudacris maculata ) reared on sediments from 3 local wetlands and a control source. To help provide environmental context for the experiment, we also measured chloride concentrations in 6 brine-contaminated wetlands in our study area, including the 2 contaminated sites used for sediment exposures. Survival of frog larvae during 46- and 55-day experiments differed by up to 88% among sediment sources (Site Model) and was negatively correlated with potential chloride exposure (Chloride Model). Five of the 6 contaminated wetlands exceeded the U.S. EPA acute benchmark for chloride in freshwater (860 mg/L) and all exceeded the chronic benchmark (230 mg/L). However, the Wetland Site model explained more variation in survival than the Chloride Model, suggesting that chloride concentration alone does not fully reflect the threat of contamination to aquatic species. Because the profiles of brine-contaminated sediments are complex, further surveys and experiments are needed across a broad range of conditions, especially where restoration or remediation actions have reduced brine-contamination. Information provided by this study can help quantify potential ecological threats and help land managers prioritize conservation strategies as part of responsible and sustainable energy development.

Montana, North Dakota, South Dakota↗

USGS2009

Adaptive management: The U.S. Department of the Interior technical guide

The purpose of this technical guide is to present an operational definition of adaptive management, identify the conditions in which adaptive management should be considered, and describe the process of using adaptive management for managing natural resources. The guide is not an exhaustive discussion of adaptive management, nor does it include detailed specifications for individual projects. However, it should aid U.S. Department of the Interior (DOI) managers and practitioners in determining when and how to apply adaptive management. Adaptive management is framed within the context of structured decision making, with an emphasis on uncertainty about resource responses to management actions and the value of reducing that uncertainty to improve management. Though learning plays a key role in adaptive management, it is seen here as a means to an end, namely good management, and not an end in itself. The operational definition used in the guide is adopted from the National Research Council, which characterizes adaptive management as an iterative learning process producing improved understanding and improved management over time: Adaptive management [is a decision process that] promotes flexible decision making that can be adjusted in the face of uncertainties as outcomes from management actions and other events become better understood. Careful monitoring of these outcomes both advances scientific understanding and helps adjust policies or operations as part of an iterative learning process. Adaptive management also recognizes the importance of natural variability in contributing to ecological resilience and productivity. It is not a ‘trial and error’ process, but rather emphasizes learning while doing. Adaptive management does not represent an end in itself, but rather a means to more effective decisions and enhanced benefits. Its true measure is in how well it helps meet environmental, social, and economic goals, increases scientific knowledge, and reduces tensions among stakeholders. Adaptive management as defined here involves ongoing, real-time learning and knowledge creation, both in a substantive sense and in terms of the adaptive process itself. It is described in what follows in a series of 9 steps, as summarized in section 4.1, involving stakeholder involvement, management objectives, management alternatives, predictive models, monitoring plans, decision making, monitoring responses to management, assessment, and adjustment to management actions. An adaptive approach actively engages stakeholders in all phases of a project over its timeframe, facilitating mutual learning and reinforcing the commitment to learning-based management. Adaptive management in DOI is implemented within a legal context that includes statutory authorities such as the National Environmental Policy Act (NEPA), the Endangered Species Act, and the Federal Advisory Committee Act. For many important problems now facing the resource management community, adaptive management holds great promise in reducing the uncertainties that limit the effective management of natural resource systems. For many conservation and management problems, utilizing management itself in an experimental context may be the only feasible way to gain the system understanding needed to improve management. Though it is commonly thought that an adaptive approach can produce results quickly at low cost, the opposite is more likely to be true. An initial investment of time and effort will increase the likelihood of better decision making and resource stewardship in the future, but patience, flexibility, and support are needed over the life of an adaptive management project. For these reasons it is important to carefully consider the potential use of an adaptive approach, and to engage in careful planning and evaluation when adaptive management is used.

Report↗

USGS2008

Understanding contaminants associated with mineral deposits

Interdisciplinary studies by the U.S. Geological Survey (USGS) have resulted in substantial progress in understanding the processes that control the release of metals and acidic water from inactive mines and mineralized areas, the transport of metals and acidic water to streams, and the fate and effect of metals and acidity on downstream ecosystems. The potential environmental effects associated with abandoned and inactive mines, resulting from the complex interaction of a variety of chemical and physical processes, is an area of study that is important to the USGS Mineral Resources Program. Understanding the processes contributing to the environmental effects of abandoned and inactive mines is also of interest to a wide range of stakeholders, including both those responsible for managing lands with historically mined areas and those responsible for anticipating environmental consequences of future mining operations. The recently completed (2007) USGS project entitled 'Process Studies of Contaminants Associated with Mineral Deposits' focused on abandoned and inactive mines and mineralized areas in the Rocky Mountains of Montana, Colorado, New Mexico, Utah, and Arizona, where there are thousands of abandoned mines. Results from these studies provide new information that advances our understanding of the physical and biogeochemical processes causing the mobilization, transport, reaction, and fate of potentially toxic elements (including aluminum, arsenic, cadmium, copper, iron, lead, and zinc) in mineralized near-surface systems and their effects on aquatic and riparian habitat. These interdisciplinary studies provide the basis for scientific decisionmaking and remedial action by local, State, and Federal agencies charged with minimizing the effects of potentially toxic elements on the environment. Current (2007) USGS research highlights the need to understand (1) the geologic sources of metals and acidity and the geochemical reactions that release them from their sources, (2) the pathways that facilitate transport from those sources, and (3) the processes that control the fate of the elements once released from the sources. Experts in the fields of economic geology, structural geology, mineralogy, geophysics, geochemistry, hydrology, ground-water modeling, microbiology, and toxicology came together for a series of studies that address these relationships on scales ranging from the microscopic to the watershed. This Circular presents results and highlights from the detailed, interdisciplinary studies that include investigations in both mining-affected areas and mineralized but unmined areas. The first section of the Circular describes laboratory and site-scale field investigations that primarily focus on mineralogic and biologic controls on the source and release of metals and acidity from mine-waste rock and hydrothermally altered areas. The second section describes a set of basin- to watershed-scale studies that not only investigate the source and release of metals and acidity but also the transport of these constituents away from the source areas. The third section is a summary of results from postremediation ecosystem monitoring. For more information on these and other project-related studies, please visit the project Web site at http://minerals.cr.usgs.gov/projects/contaminants/index.html. The Web site includes a complete bibliography and detailed descriptions of each interdisciplinary study.

Circular↗

USGS2018

Iterative near-term ecological forecasting: Needs, opportunities, and challenges

Two foundational questions about sustainability are “How are ecosystems and the services they provide going to change in the future?” and “How do human decisions affect these trajectories?” Answering these questions requires an ability to forecast ecological processes. Unfortunately, most ecological forecasts focus on centennial-scale climate responses, therefore neither meeting the needs of near-term (daily to decadal) environmental decision-making nor allowing comparison of specific, quantitative predictions to new observational data, one of the strongest tests of scientific theory. Near-term forecasts provide the opportunity to iteratively cycle between performing analyses and updating predictions in light of new evidence. This iterative process of gaining feedback, building experience, and correcting models and methods is critical for improving forecasts. Iterative, near-term forecasting will accelerate ecological research, make it more relevant to society, and inform sustainable decision-making under high uncertainty and adaptive management. Here, we identify the immediate scientific and societal needs, opportunities, and challenges for iterative near-term ecological forecasting. Over the past decade, data volume, variety, and accessibility have greatly increased, but challenges remain in interoperability, latency, and uncertainty quantification. Similarly, ecologists have made considerable advances in applying computational, informatic, and statistical methods, but opportunities exist for improving forecast-specific theory, methods, and cyberinfrastructure. Effective forecasting will also require changes in scientific training, culture, and institutions. The need to start forecasting is now; the time for making ecology more predictive is here, and learning by doing is the fastest route to drive the science forward.

Proceedings of the National Academy of Sciences of↗

USGS2022

Simulating burn severity maps at 30 meters in two forested regions in California

Climate change is altering wildfire behavior and vegetation regimes in California’s forested ecosystems. Present day fires are seeing an increase in high burn severity area and high severity patch size. The ability to predict future burn severity patterns would support better policy and land management decisions. Here we demonstrate a methodology to first, statistically estimate individual burn severity classes at 30 meters and second, cluster and smooth high severity patches onto a landscape. Our goal here was not to exactly replicate observed burn severity maps, but rather to utilize observed maps as one realization of a random process dependent on climate, topography, fire weather, and fuels, to inform creation of additional realizations through our simulation technique. We developed two sets of empirical models with two different vegetation datasets to test if coarse vegetation could accurately model for burn severity. While visual acuity can be used to assess the performance of our simulation process, we also employ the Ripley’s K function to compare spatial point processes at different scales to test if the simulation is capturing an appropriate amount of clustering. We utilize FRAGSTATS to obtain high severity patch metrics to test the contiguity of our high severity simulation. Ripley’s K function helped identify the number of clustering iterations and FRAGSTATS showed how different focal window sizes affected our ability to cluster high severity patches. High severity patch simulations was comparable between the coarse and fine resolution vegetation datasets. Improving our ability to simulate burn severity will help advance our understanding of the potential influence of land and fuels management on ecosystem-level response variables that are important for decision-makers. Simulated burn severity maps can support managing habitat and estimating risks of habitat loss, protecting infrastructure and homes, improving future wildfire emissions projections, and better mapping and planning for fuels treatment scenarios.

California↗

USGS2022

Volcano and earthquake monitoring plan for the Yellowstone Caldera system, 2022–2032

Executive Summary The Yellowstone Volcano Observatory (YVO) is a consortium of nine Federal, State, and academic agencies that: (1) provides timely monitoring and hazards assessment of volcanic, hydrothermal, and earthquake activity in and around Yellowstone National Park, and (2) conducts research to develop new approaches to volcano monitoring and better understand volcanic activity in the Yellowstone region and elsewhere. The U.S. Geological Survey (USGS) arm of YVO is also responsible for monitoring and reporting on volcanic activity in the Intermountain West of the United States. The previous YVO monitoring plan for the Yellowstone region spanned 2006–2015 and focused on strengthening the region-wide coverage, or backbone, of monitoring systems (Yellowstone Volcano Observatory, 2006). The goals of that plan have largely been achieved thanks to significant investments in instrumentation and infrastructure, especially by the National Science Foundation EarthScope Plate Boundary Observatory (now known as the Network Of The Americas, or NOTA) and the American Reinvestment and Recovery Act. This revision of the monitoring plan, covering 2022–2032, builds upon these improvements to monitoring systems in the Yellowstone region while also accounting for new insights into the dynamics of the area’s seismic, volcanic, and hydrothermal activity. These additional improvements are designed to fill gaps in the monitoring network and to better understand and track hazards associated with hydrothermal processes. These improvements include: Conversion of remaining analog seismic stations to digital, Addition of Global Positioning System (GPS) stations in the vicinity of Norris Geyser Basin and other areas where changes in deformation rate and style have been observed, Implementation of continuous gas monitoring in several areas of Yellowstone National Park, and Improvements to lake, meteorological, and hydrological monitoring to better track hydrothermal activity, including that occurring on lake bottoms, and to aid in understanding of whether such activity might be influenced by external forces, like environmental conditions. The 2022–2032 monitoring plan for the Yellowstone volcanic system also proposes to improve monitoring of hydrothermal areas to better understand these dynamic systems and their associated hazards. To date, only a single seismometer has been placed within one of Yellowstone National Park’s geyser basins because seismic noise associated with boiling water can hinder interpretation of overall seismic and magmatic activity, but this concern has been mitigated by improvements to backbone monitoring. Deployment of geophysical, geochemical, hydrological, and geological monitoring instruments in geyser basins will be accompanied by campaigns to measure gas and water chemistry and flux, as well as aerial and satellite surveys of gas and thermal emissions. Close collaboration between YVO member institutions and other research agencies is needed to achieve these monitoring goals and to use the derived data to advance understanding of how Yellowstone Caldera and similar volcanic systems work. At the same time, attention must be paid to minimize the impact of monitoring efforts and infrastructure on the environment. YVO thus commits to serving as stewards of the natural, cultural, and historical resources in and around Yellowstone National Park while maximizing scientific gain for the betterment of society.

Wyoming↗

USGS2008

Correlation of the Deccan and Rajahmundry Trap lavas: Are these the longest and largest lava flows on Earth?

We propose that the Rajahmundry Trap lavas, found near the east coast of peninsular India , are remnants of the longest lava flows yet recognized on Earth (∼ 1000 km long). These outlying Deccan-like lavas are shown to belong to the main Deccan Traps. Several previous studies have already suggested this correlation, but have not demonstrated it categorically. The exposed Rajahmundry lavas are interpreted to be the distal parts of two very-large-volume pāhoehoe flow fields, one each from the Ambenali and Mahabaleshwar Formations of the Wai Sub-group in the Deccan Basalt Group. Eruptive conditions required to emplace such long flows are met by plausible values for cooling and eruption rates, and this is shown by applying a model for the formation of inflated pāhoehoe sheet flow lobes. The model predicts flow lobe thicknesses similar to those observed in the Rajahmundry lavas. For the last 400 km of flow, the lava flows were confined to the pre-existing Krishna valley drainage system that existed in the basement beyond the edge of the gradually expanding Deccan lava field, allowing the flows to extend across the subcontinent to the eastern margin where they were emplaced into a littoral and/or shallow marine environment. These lavas and other individual flow fields in the Wai Sub-group may exceed eruptive volumes of 5000 km 3 , which would place them amongst the largest magnitude effusive eruptive units yet known. We suggest that the length of flood basalt lava flows on Earth is restricted mainly by the size of land masses and topography. In the case of the Rajahmundry lavas, the flows reached estuaries and the sea, where their advance was perhaps effectively terminated by cooling and/or disruption. However, it is only during large igneous province basaltic volcanism that such huge volumes of lava are erupted in single events, and when the magma supply rate is sufficiently high and maintained to allow the formation of very long lava flows. The Rajahmundry lava fields were emplaced around 65 Ma during the later times of Deccan volcanism, probably just after the K/T environmental crisis. However, many lava-forming eruptions of similar magnitude and style straddled the K/T boundary.

Rajahmundry Trap↗

USGS2018

Phenological mismatch in coastal western Alaska may increase summer season greenhouse gas uptake

High latitude ecosystems are prone to phenological mismatches due to climate change- driven advances in the growing season and changing arrival times of migratory herbivores. These changes have the potential to alter biogeochemical cycling and contribute to feedbacks on climate change by altering greenhouse gas (GHG) emissions of carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O) through large regions of the Arctic. Yet the effects of phenological mismatches on gas fluxes are currently unexplored. We used a three-year field experiment that altered the start of the growing season and timing of grazing to investigate how phenological mismatch affects GHG exchange. We found early grazing increased mean GHG emission to the atmosphere despite lower CH 4 emissions due to grazing-induced changes in vegetation structure that increased uptake of CO 2 . In contrast, late grazing reduced GHG emissions because greater plant productivity led to an increase in CO 2 uptake that overcame the increase in CH 4 emission. Timing of grazing was an important control on both CO 2 and CH 4 emissions, and net GHG exchange was the result of opposing fluxes of CO 2 and CH 4 . N 2 O played a negligible role in GHG flux. Advancing the growing season had a smaller effect on GHG emissions than changes to timing of grazing in this study. Our results suggest that a phenological mismatch that delays timing of grazing relative to the growing season, a change which is already developing along in western coastal Alaska, will reduce GHG emissions to the atmosphere through increased CO 2 uptake despite greater CH 4 emissions.

Environmental Research Letters↗

USGS2014

Brine contamination to aquatic resources from oil and gas development in the Williston Basin, United States

The Williston Basin, which includes parts of Montana, North Dakota, and South Dakota in the United States and the provinces of Manitoba and Saskatchewan in Canada, has been a leading domestic oil and gas producing region for more than one-half a century. Currently, there are renewed efforts to develop oil and gas resources from deep geologic formations, spurred by advances in recovery technologies and economic incentives associated with the price of oil. Domestic oil and gas production has many economic benefits and provides a means for the United States to fulfill a part of domestic energy demands; however, environmental hazards can be associated with this type of energy production in the Williston Basin, particularly to aquatic resources (surface water and shallow groundwater) by extremely saline water, or brine, which is produced with oil and gas. The primary source of concern is the migration of brine from buried reserve pits that were used to store produced water during recovery operations; however, there also are considerable risks of brine release from pipeline failures, poor infrastructure construction, and flow-back water from hydraulic fracturing associated with modern oilfield operations. During 2008, a multidisciplinary (biology, geology, water) team of U.S. Geological Survey researchers was assembled to investigate potential energy production effects in the Williston Basin. Researchers from the U.S. Geological Survey participated in field tours and met with representatives from county, State, tribal, and Federal agencies to identify information needs and focus research objectives. Common questions from agency personnel, especially those from the U.S. Fish and Wildlife Service, were “are the brine plumes (plumes of brine-contaminated groundwater) from abandoned oil wells affecting wetlands on Waterfowl Production Areas and National Wildlife Refuges?” and “are newer wells related to Bakken and Three Forks development different than the older, abandoned wells (in terms of potential for affecting aquatic resources)?” Of special concern were the wetland habitats of the ecologically important Prairie Pothole Region, which overlays a part of the Williston Basin and is recognized for the production of a majority of North America’s migratory waterfowl. On the basis of the concerns raised by on-the-ground land managers, as well as findings from previous research, a comprehensive study was developed with the following goals: summarize existing information pertaining to oil and gas production and aquatic resources in the Williston Basin; assess brine plume migration from new and previously studied sites in the Prairie Pothole Region; perform a regional, spatial evaluation of oil and gas production activities and aquatic resources; assess the potential for brine contamination to wetlands and streams; and hold a decision analysis workshop with key stakeholders to discuss issues pertaining to oil and gas production and environmental effects and to identify information gaps and research needs. This report represents an initial, multidisciplinary evaluation of measured and potential environmental effects associated with oil and gas production in the Williston Basin and Prairie Pothole Region. Throughout this report there are reviews of current knowledge, and discussions relating to data gaps and research needs. On the basis of the information presented, future research needs include: regional geophysical and water-quality assessments to establish baselines for current conditions and estimate the extent of previous brine contamination, investigations into the direct effects of brine to biotic communities, and evaluations to identify the most effective techniques to mitigate brine contamination.

Montana, North Dakota↗

USGS2002

A modular approach to addressing model design, scale, and parameter estimation issues in distributed hydrological modelling

A modular approach to model design and construction provides a flexible framework in which to focus the multidisciplinary research and operational efforts needed to facilitate the development, selection, and application of the most robust distributed modelling methods. A variety of modular approaches have been developed, but with little consideration for compatibility among systems and concepts. Several systems are proprietary, limiting any user interaction. The US Geological Survey modular modelling system (MMS) is a modular modelling framework that uses an open source software approach to enable all members of the scientific community to address collaboratively the many complex issues associated with the design, development, and application of distributed hydrological and environmental models. Implementation of a common modular concept is not a trivial task. However, it brings the resources of a larger community to bear on the problems of distributed modelling, provides a framework in which to compare alternative modelling approaches objectively, and provides a means of sharing the latest modelling advances. The concepts and components of the MMS are described and an example application of the MMS, in a decision-support system context, is presented to demonstrate current system capabilities. Copyright ?? 2002 John Wiley and Sons, Ltd.

Hydrological Processes↗

USGS2018

Drain tiles and groundwater resources: Understanding the relations

Executive Summary Drainage for agricultural production over the past 150 years has been an integral component of human-driven change to Minnesota’s rural landscapes. Benefits of drainage Historically, poorly drained soils across much of the State would often remain saturated or flooded after spring snowmelt, preventing timely farm operations such as tilling and planting crops (Arneman, 1963). Installation of agricultural drainage, both surface ditches and subsurface drainage, accelerated transport of water off farm fields and imparted producers higher crop yields (Beauchamp, 1987; Stoner and others, 1993). Agricultural drainage offered many other benefits such as preventing crop drown out, aerating the soil profile for improved plant growth, limiting surface runoff and soil erosion, and allowing farmers better access to croplands (Fausey and others, 1987). Without agricultural drainage on much of Minnesota’s croplands, it would have been difficult to realize high enough crop yields to remain economically viable. Environmental concerns While drainage of Minnesota croplands provided the benefits mentioned above, several environmental concerns result. These include wetland loss, degradation of downstream water quality, and reduced [potential for] recharge. Early agricultural drainage efforts (pre-20th century) led to the disappearance of much of Minnesota’s natural wetlands. Increased focus on preventing or mitigating wetland loss over the last 50 years has helped curtail further losses, even as agricultural drainage proceeds. Prior to establishment of Minnesota statehood, wetlands accounted for more than 10 million acres in Minnesota, including prairie wetlands, peatlands, and forest wetlands that comprised approximately 19 percent of the total land area (Palmer, 1915; King, 1980). In 2018, only half of Minnesota’s pre-settlement wetlands remain, mostly in parts of the State that have not experienced widespread drainage, such as northern Minnesota. Water-quality monitoring has shown that agricultural drainage, in particular the practice of subsurface drainage, provides a direct flow path for nutrient (nitrogen and soluble phosphorus) losses to surface water resources. The negative consequences of agricultural drainage on surface water quality are well documented (for example, Dinnes and others, 2002; Kladivko and others, 2004; Richards and others, 2008; Rozemeijer and others, 2010; Schottler and others, 2013). Agricultural basins with a high percentage of agricultural drainage have been implicated as part of the cause of the Gulf of Mexico hypoxia zone due to excessive nitrogen export (Goolsby and Battaglin, 2001; Randall and Mulla, 2001). The connection of hydrological effects of agricultural subsurface drainage on groundwater recharge and aquifers, on the other hand, has not been well-established. Agricultural subsurface drainage intercepts infiltrating water below croplands and directly discharges the water to nearby surface waters. However, the size of the water balance shift from drained water that would have evapotranspired or run off the land to drained water that would recharge underlying aquifers has been poorly characterized (Schuh, 2008). Drain Tiles and Groundwater Given the poor accounting of subsurface drainage effects on groundwater resources, the Minnesota Ground Water Association (MGWA) deemed it imperative that we document these effects so that groundwater resources in agricultural regions with substantial drainage can be effectively managed. This white paper documents the relations of drain tiles and groundwater resources and discusses the historical significance of agricultural drainage practices, the recognized positive benefits and potential negative consequences of agricultural drainage practices, and the gaps in understanding of the connections between agricultural drainage and groundwater resources. The major messages emerged from the findings of this white paper are: Complex history. Minnesota has a long history of agricultural drainage, spanning over 150 years. Agricultural drainage, and the eventual widespread usage of subsurface drainage, can be separated into at least four distinct periods of time: (a) early drainage to get water off the land, pre-20th century; (b) the boom and bust era (1900-1945); (c) postwar resurgence of subsurface drainage and early conservation efforts (1945-1960); and, (d) emergence of the environmental movement (1960 to present). The State’s regulatory framework that both allowed for drainage and controlled its usage during these periods is complicated and has been governed by a patchwork of both State and Federal statutes. Drainage Provinces. This white paper advances the concept of tile drainage provinces to aid in the discussion of regional differences in subsurface drainage and its overall effect on groundwater resources. Built upon the concept of groundwater provinces (Minnesota Department of Natural Resources, 2001), three distinct tile drainage provinces were conceptualized: (1) the Southeastern Province; (2) the SouthCentral Province; and, (3) the Western Province. The distinct geology and the soils that developed in these regions have implications for each region’s subsurface drainage density and the potential implications for groundwater. Knowledge gaps. Several critical knowledge gaps are identified in this paper, creating opportunities for further research to improve our understanding for better managed water resources: Extent of drainage is unknown. Direct estimates of the extent of subsurface drainage do not exist in Minnesota. However, several indirect methods have been utilized to estimate subsurface drainage, from the field-scale to countylevel through the use of geographic information system (GIS) analysis and aerial photography. Based on a 2012 U.S. Geological Survey estimate of subsurface drainage extent (Nakagaki and Wieczorek, 2016), about 21% of the land area in Minnesota has some density of subsurface drainage. Effect of drainage on underlying aquifers is unknown. A basic understanding of unconfined and confined aquifers and their recharge is necessary to connect any hydrological effects from agricultural drainage to groundwater. The basic goal of subsurface drainage to efficiently drain saturated soils clearly alters the water balance in croplands. However, its overall effect on groundwater resources has been poorly characterized, and is in large part determined by the geology below drained areas and the arrangement of underlying aquifers. Water balance shifts. An improved understanding of historical water balance shifts from pre- to post-drainage periods is necessary to understand long-term implications on net groundwater recharge. Also, more direct field-scale studies and indirect modeling studies are needed to characterize water budgets for fields with subsurface drainage.

Minnesota↗