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At least 91 records · Page 5Linked to original sources
USGS2018

Three visualization approaches for communicating and exploring PIT tag data

As the number, size and complexity of ecological datasets has increased, narrative and interactive raw data visualizations have emerged as important tools for exploring and understanding these large datasets. As a demonstration, we developed three visualizations to communicate and explore passive integrated transponder tag data from two long-term field studies. We created three independent visualizations for the same dataset, allowing separate entry points for users with different goals and experience levels. The first visualization uses a narrative approach to introduce users to the study. The second visualization provides interactive cross-filters that allow users to explore multi-variate relationships in the dataset. The last visualization allows users to visualize the movement histories of individual fish within the stream network. This suite of visualization tools allows a progressive discovery of more detailed information and should make the data accessible to users with a wide variety of backgrounds and interests.

Maine, Massachusetts↗
USGS2014

Effects of disturbance associated with seismic exploration for oil and gas reserves in coastal marshes

Anthropogenic disturbances in wetland ecosystems can alter the composition and structure of plant assemblages and affect system functions. Extensive oil and gas extraction has occurred in wetland habitats along the northern Gulf of Mexico coast since the early 1900s. Activities involved with three-dimensional (3D) seismic exploration for these resources cause various disturbances to vegetation and soils. We documented the impact of a 3D seismic survey in coastal marshes in Louisiana, USA, along transects established before exploration began. Two semi-impounded marshes dominated by Spartina patens were in the area surveyed. Vegetation, soil, and water physicochemical data were collected before the survey, about 6 weeks following its completion, and every 3 months thereafter for 2 years. Soil cores for seed bank emergence experiments were also collected. Maximum vegetation height at impact sites was reduced in both marshes 6 weeks following the survey. In one marsh, total vegetation cover was also reduced, and dead vegetation cover increased, at impact sites 6 weeks after the survey. These effects, however, did not persist 3 months later. No effects on soil or water properties were identified. The total number of seeds that germinated during greenhouse studies increased at impact sites 5 months following the survey in both marshes. Although some seed bank effects persisted 1 year, these effects were not reflected in standing vegetation. The marshes studied were therefore resilient to the impacts resulting from 3D seismic exploration because vegetation responses were short term in that they could not be identified a few months following survey completion.

Louisiana↗
USGS1966

Mineral exploration and soil analysis using in situ neutron activation

A feasibility study has been made to operate by remote control an unshielded portable positive-ion accelerator type neutron source to induce activities in the ground or rock by “in situ” neutron irradiation. Selective activation techniques make it possible to detect some thirty or more elements by irradiating the ground for periods of a few minutes with either 3-MeV or 14-MeV neutrons. The depth of penetration of neutrons, the effect of water content of the soil on neutron moderation, gamma ray attenuation in the soil and other problems are considered. The analysis shows that, when exploring for most elements of economic interest, the reaction 2 H(d,n) 3 He yielding ∼ 3-MeV neutrons is most practical to produce a relatively uniform flux of neutrons of less than 1 keV to a depth of 19″–20″. Irradiation with high energy neutrons (∼ 14 MeV) can also be used and may be better suited for certain problems. However, due to higher background and lower sensitivity for the heavy minerals, it is not a recommended neutron source for general exploration use. Preliminary experiments have been made which indicate that neutron activation in situ is feasible for a mineral exploration or qualititative soil analysis.

Nuclear Instruments and Methods↗
USGS2022

Indicator mineral analyses of stream-sediment samples using automated mineralogy and mineral chemistry: Applicability to exploration in covered terranes in eastern Alaska, USA

In the past two decades, significant research efforts have been devoted to porphyry copper indicator mineral (PCIM) identification and mineral chemistry to assist exploration. Such studies are important in the Yukon-Tanana upland region of eastern Alaska because well-established geochemical exploration techniques, such as the geochemistry of stream-sediment samples, are less effective in the search for mineral resources owing to cover materials that subdue geochemical signatures. The unglaciated Yukon-Tanana upland region is well-endowed with mineral resources, including porphyry Cu-Mo-Au deposits at Taurus, Bluff, Dennison, and Oreo. Using automated scanning electron microscope (SEM) techniques, numerous PCIMs have been identified in rocks and stream-sediment samples that would likely not have been observed using visual binocular microscope methods. Sulfide minerals such as chalcopyrite, chalcocite, covellite, bornite, molybdenite, and pyrrhotite were identified in rock samples, and more than half of the stream-sediment samples from drainages containing known porphyry mineral occurrences contain chalcopyrite with or without bornite. Many drainages without known occurrences also contain these minerals, which suggests potential for additional occurrences. Svanbergite, an aluminum phosphate sulfate (APS) mineral [SrAl 3 (PO 4 )(SO 4 )(OH) 6 ], was identified in some of the altered or mineralized rock samples from Taurus, and in stream drainages containing porphyry occurrences and may represent the best indicator mineral for Taurus-like porphyry deposits. Apatite chemistry has great potential as a tool for assessing the presence of porphyry mineralization. Grains from rock and stream-sediment samples that contain high Cl (>∼0.4 wt%), Fe (>0.4 wt%), and Mn (>2000 ppm) clearly distinguish apatite from other sources (metamorphic, unmineralized igneous rocks). This study is one of the first to document new streamlined indicator mineral sample collection and processing methods and to combine automated SEM techniques and chemistry of minerals derived from both bedrock and surficial (stream) sediments as they apply to porphyry exploration.

Alaska↗
USGS2024

From exploration to production: Understanding the development dynamics of lithium mining projects

Recently, there has been considerable recent controversy whether current and new lithium mines will be able to supply the rapidly growing needs of the electromobility transition. Mineral exploration projects are typically active for many years, and only some become operational mines. From exploration to production, the projects go through several stages of characterisation and evaluation. At each stage, decisions are made by companies and stakeholders to advance, continue or stop the project. This is a complex process, and even projects with very similar geological and technical characteristics may take very different trajectories, depending on external factors such as global market conditions and local regulatory environments. The present study investigates the dynamics of this process for lithium exploration projects. A global database of 397 lithium projects was compiled, covering their progression through major development stages between 2004 and 2022. Ordinal logistic regression was used for the statistical analysis of this data. Different explanatory variables were tested, including economic, geological, technical, and geographic factors, to identify the best predictors for project progress at each development stage. The results suggest an essential role for lithium carbonate prices, and a variable role for other factors at each stage. Critically, the already elapsed lead time and project economics, which are traditionally considered important for the prediction of the start-up of individual mines, do not appear to be relevant in all cases. The results provide important insights into the dynamics of lithium supply and may eventually allow more realistic forecasts to be made for future lithium market dynamics.

Resources Policy↗
USGS2022

Fundamental science and engineering questions in planetary cave exploration

Nearly half a century ago, two papers postulated the likelihood of lunar lava tube caves using mathematical models. Today, armed with an array of orbiting and fly-by satellites and survey instrumentation, we have now acquired cave data across our solar system—including the identification of potential cave entrances on the Moon, Mars, and at least six other planetary bodies. These discoveries gave rise to the study of planetary caves. To help advance this field, we leveraged the expertise of an interdisciplinary group to identify a strategy to explore caves beyond Earth. Focusing primarily on astrobiology, the cave environment, geology, robotics, instrumentation, and human exploration, our goal was to produce a framework to guide this subdiscipline through at least the next decade. To do this, we first assembled a list of 198 science and engineering questions. Then, through a series of social surveys, 114 scientists and engineers winnowed down the list to the top 53 highest priority questions. This exercise resulted in identifying emerging and crucial research areas that require robust development to ultimately support a robotic mission to a planetary cave—principally the Moon and/or Mars. With the necessary financial investment and institutional support, the research and technological development required to achieve these necessary advancements over the next decade are attainable. Subsequently, we will be positioned to robotically examine lunar caves and search for evidence of life within martian caves; in turn, this will set the stage for human exploration and potential habitation of both the lunar and martian subsurface.

JGR Planets↗
USGS2014

Deep‐well salinity‐exploration

One of the outstanding accomplishments of recent years in connection with the study of the geologic source of groundwater and the quality of water yielded by different formations has been the development of methods and equipment for the exploration of wells. The description and use of the deep ‐ well current‐meter on well ‐ exploration work in Hawaii and New Mexico has already appeared in published literature (John McCombs and A. G. Fiedler, Methods of exploring and repairing leaky artesian wells, U.S. Geol. Sur. Water‐Supply Paper 596, pp. 1–32, 1928) on hydrology but recent developments in the application of electrical conductivity‐measurements for determining the salinity of water in wells have not heretofore been presented. In addition to being of considerable scientific importance in connection with problems of ground‐water hydrology, the practical value of locating the place at which salt water is entering a well and contaminating a potable water‐supply is great. Such information may be the means of preventing the loss of large investments in industries, irrigation‐projects, and cities that are dependent upon well ‐water supplies that may at some time become contaminated by salty or other highly mineralized water.

Nevada, Hawaii↗
USGS2021

A roadmap for planetary caves science and exploration

While researchers have pondered the possibility of extraterrestrial caves for more than 50 years, we have now entered the incipient phase of planetary caves exploration. Our knowledge of planetary caves varies from body to body. Earth represents the most advanced level of exploration, but many unanswered questions remain. Beyond Earth, identification of possible caves is most advanced for the Moon and Mars , with hundreds of documented candidate cave entrances and several proposed cave mission concepts. To date, the community has catalogued 2,660 SAPs on eight planetary bodies (excluding Earth) across our Solar System. Planetary caves science has the potential to significantly expand over the next decade. A potential roadmap for planetary cave research and exploration is discussed.

Nature Astronomy↗
USGS2018

Spatial spectroscopic models for remote exploration

Ancient hydrothermal systems are a high-priority target for a future Mars sample return mission because they contain energy sources for microbes and can preserve organic materials (Farmer, 2000 ; MEPAG Next Decade Science Analysis Group, 2008 ; McLennan et al., 2012 ; Michalski et al., 2017 ). Characterizing these large, heterogeneous systems with a remote explorer is difficult due to communications bandwidth and latency; such a mission will require significant advances in spacecraft autonomy. Science autonomy uses intelligent sensor platforms that analyze data in real-time, setting measurement and downlink priorities to provide the best information toward investigation goals. Such automation must relate abstract science hypotheses to the measurable quantities available to the robot. This study captures these relationships by formalizing traditional “science traceability matrices” into probabilistic models. This permits experimental design techniques to optimize future measurements and maximize information value toward the investigation objectives, directing remote explorers that respond appropriately to new data. Such models are a rich new language for commanding informed robotic decision making in physically grounded terms. We apply these models to quantify the information content of different rover traverses providing profiling spectroscopy of Cuprite Hills, Nevada. We also develop two methods of representing spatial correlations using human-defined maps and remote sensing data. Model unit classifications are broadly consistent with prior maps of the site's alteration mineralogy, indicating that the model has successfully represented critical spatial and mineralogical relationships at Cuprite. Key Words: Autonomous science—Imaging spectroscopy—Alteration mineralogy—Field geology—Cuprite—AVIRIS-NG—Robotic exploration. Astrobiology 18, 934–954.

Astrobiology↗
USGS2006

Examples of transient sounding from groundwater exploration in sedimentary aquifers

Examples of the use of transient electromagnetic soundings for three ground-water exploration problems in sedimentary aquifers are given. The examples include: (1) estimating depths to water table and bedrock in an alluvium-filled basin, (2) mapping a confined fresh-water aquifer in bedrock sediments, and (3) locating a freshwater/salt-water interface in a glacial-outwash aquifer. The technique works quite well for these problems within the limitations imposed by the problem of equivalence. For thin conductive targets (S-equivalence) such as a salt-water lens, the ratio of the layer thickness to its resistivity can be determined, but not the individual layer parameters. The thickness of thin resistive zones (H-equivalence) can be resolved, but the resistivity of such layers is not well determined. The problem of H-equivalence is more severe than the S-equivalence. Equivalence imposes restrictions on the transient sounding method for some ground-water exploration problems. Model studies prior to field work can be used to assess the usefulness of the technique for a particular exploration objective.

Groundwater↗
USGS2020

Climate explorer: Improved access to local climate projections

The goal of the U.S. Climate Resilience Toolkit’s (CRT) Climate Explorer (CE) is to provide information at appropriate spatial and temporal scales to help practitioners gain insights into the risks posed by climate change. Ultimately, these insights can lead to groups of local stakeholders taking action to build their resilience to a changing climate. Using CE, decision-makers can visualize decade-by-decade changes in climate conditions in their county and the magnitude of changes projected for the end of this century under two plausible emissions pathways. They can also check how projected changes relate to user-defined thresholds that represent points at which valued assets may become stressed, damaged, or destroyed. By providing easy access to authoritative information in an elegant interface, the Climate Explorer can help communities recognize—and prepare to avoid or respond to—emerging climate hazards. Another important step in the evolution of CE builds on the purposeful alignment of the CRT with the U.S. Global Change Research Program’s (USGCRP) National Climate Assessment (NCA). By closely linking these two authoritative resources, we envision that users can easily transition from static maps and graphs within NCA reports to dynamic, interactive versions of the same data within CE and other resources within the CRT, which they can explore at higher spatial scales or customize for their own purposes. The provision of consistent climate data and information—a result of collaboration among USGCRP’s federal agencies—will assist decision-making by other governmental entities, nongovernmental organizations, businesses, and individuals.

Article↗
USGS2003

Utility of high-altitude infrared spectral data in mineral exploration: Application to Northern Patagonia Mountains, Arizona

Synoptic views of hydrothermal alteration assemblages are of considerable utility in regional-scale minerals exploration . Recent advances in data acquisition and analysis technologies have greatly enhanced the usefulness of remotely sensed imaging spectroscopy for reliable alteration mineral assemblages mapping. Using NASA's Airborne Visible Infrared Imaging Spectrometer (AVIRIS) sensor, this study mapped large areas of advanced argillic and phyllic-argillic alteration assemblages in the southeastern Santa Rita and northern Patagonia mountains , Arizona . Two concealed porphyry copper deposits have been identified during past exploration , the Red Mountain and Sunnyside deposits, and related published hydrothermal alteration zoning studies allow the comparison of the results obtained from AVIRIS data to the more traditional field mapping approaches. The AVIRIS mapping compares favorably with field-based studies. An analysis of iron-bearing oxide minerals above a concealed supergene chalcocite deposit at Red Mountain also indicates that remotely sensed data can be of value in the interpretation of leached caps above porphyry copper deposits. In conjunction with other types of geophysical data , AVIRIS mineral maps can be used to discriminate different exploration targets within a region.

Economic Geology↗
USGS2006

Quantitative methods to direct exploration based on hydrogeologic information

Quantitatively Directed Exploration (QDE) approaches based on information such as model sensitivity, input data covariance and model output covariance are presented. Seven approaches for directing exploration are developed, applied, and evaluated on a synthetic hydrogeologic site. The QDE approaches evaluate input information uncertainty, subsurface model sensitivity and, most importantly, output covariance to identify the next location to sample. Spatial input parameter values and covariances are calculated with the multivariate conditional probability calculation from a limited number of samples. A variogram structure is used during data extrapolation to describe the spatial continuity, or correlation, of subsurface information. Model sensitivity can be determined by perturbing input data and evaluating output response or, as in this work, sensitivities can be programmed directly into an analysis model. Output covariance is calculated by the First-Order Second Moment (FOSM) method, which combines the covariance of input information with model sensitivity. A groundwater flow example, modeled in MODFLOW-2000, is chosen to demonstrate the seven QDE approaches. MODFLOW-2000 is used to obtain the piezometric head and the model sensitivity simultaneously. The seven QDE approaches are evaluated based on the accuracy of the modeled piezometric head after information from a QDE sample is added. For the synthetic site used in this study, the QDE approach that identifies the location of hydraulic conductivity that contributes the most to the overall piezometric head variance proved to be the best method to quantitatively direct exploration. ?? IWA Publishing 2006.

Journal of Hydroinformatics↗
USGS1979

Nature of firm expectations in petroleum exploration

Recent interest in the state of the United States domestic petroleum industry has resulted in an increased concern regarding the ability of current large- scale econometric models to provide useful predictions about supply price sensitivity and about the effects of differing policy options on future supply. The petroleum industry's exploration and reserve response functions appear to have eluded traditional modeling approaches. Properties of firm exploration behavior are obscured when highly aggregated data are used. Data pertaining to different geographical areas are frequently combined using dummy variables to denote characteristics peculiar to a region. In these models price tends to be more related to the quality of the crude oil than to incremental costs of exploration and development of individual deposits. The effect of price changes on expected supplies is clearly moderated by the level of resource depletion for a particular basin. A major obstacle to carrying out a less aggregated analysis has been the lack of data on specific basins, but another obstacle has been the belief that field behavior is too erratic to model successful.

Land Economics↗
USGS2020

The 150th anniversary of the 1869 Powell expedition—USGS participation in the Sesquicentennial Colorado River Exploring Expedition and reflections from the ~1,000-mile journey down the Green and Colorado Rivers

In 1869, John Wesley Powell completed the first well-recorded scientific river journey to explore an extensive region of the Colorado River Basin. Powell later helped to establish the U.S. Geological Survey (USGS) and served as its second director (1881–94), cementing his position in the folklore of the Survey. In 2019, the USGS marked the 150th anniversary of Powell’s first expedition with a broad-scale educational campaign as an opportunity to highlight current USGS science in the region through the lens of an exciting river expedition, with the goal of inspiring the next generation of USGS scientists. The project included a partnership with the Sesquicentennial Colorado River Exploring Expedition (SCREE), which traveled the length of the original route for ~1,000 river miles from Green River, Wyoming, to Lake Mead, Nevada, including the Grand Canyon. Small, interdisciplinary groups of USGS employees joined each segment of the journey, gathered data to be used for educational purposes, participated in community outreach events, and upon return shared their experiences with their local communities. This report documents a photographic journey of the expedition, personal vignettes from the USGS participants, Science Stories to explain the scope of the experiments, and Then and Now articles (which were published online during the expedition), to explore some of the changes that have occurred since the first expedition.

Arizona, Colorado, Utah, Wyoming↗
USGS1978

A theoretical basis for exploration for native copper in northern Wisconsin

Exploration for native copper in the Keweenawan lavas of northern Wisconsin has been concentrated in areas of relatively shallow overburden that have sparse to numerous outcrops. Lack of success of this exploration suggests that if large deposits, comparable to those of northern Michigan, are present, they are more likely to be found in one or more of the large tracts that have few, if any, exposures, away from the ' copper ranges. ' A hydrologic model that may explain the mineralization of the classic native-copper district of Michigan could be helpful in suggesting that certain covered tracts are more favorable than others, and in narrowing the targets for physical exploration within these tracts. This model involves updip migration of a hydrothermal fluid of metamorphic origin, formed when ground water contained in the interstices of lava flows and conglomerate beds was carried to great depth along the axis of the Lake Superior syncline. The largest reservoirs of such buried ground water would be expected in the peripheral rather than central parts of the basins in which the lavas originally accumulated because the ratio of porous fragmental flow tops and conglomerate beds to massive basalt should increase towards the margins of a basin. Thus, the areas most promising for copper deposits should be those updip from places where the trough of the later formed Lake Superior syncline crosses the marginal parts of a lava basin. (Woodard-USGS)

Circular↗
USGS2008

Areas of historical oil and gas exploration and production in the United States

This report contains maps and associated spatial data showing historical oil and gas exploration and production in the United States. Because of the proprietary nature of many oil and gas well databases, the United States was divided into cells one-quarter square mile and the production status of all wells in a given cell was aggregated. Base-map reference data are included, using the U.S. Geological Survey (USGS) National Map, the USGS and American Geological Institute (AGI) Global GIS, and a World Shaded Relief map service from the ESRI Geography Network. A hardcopy map was created to synthesize recorded exploration data from 1859, when the first oil well was drilled in the U.S., to 2005. In addition to the hardcopy map product, the data have been refined and made more accessible through the use of Geographic Information System (GIS) tools. The cell data are included in a GIS database constructed for spatial analysis via the USGS Internet Map Service or by importing the data into GIS software such as ArcGIS. The USGS internet map service provides a number of useful and sophisticated geoprocessing and cartographic functions via an internet browser. Also included is a video clip of U.S. oil and gas exploration and production through time.

Data Series↗
USGS2018

Land treatment exploration tool

Overview Land managers make decisions regarding restoration and rehabilitation actions that influence landscapes and ecosystems. Many of these decisions involve soil and vegetation manipulations, often known as land treatments. Historically, treatments were planned on a case by case basis with decisions derived from personal experience of past successes or failures. Current adaptive management strategies require a more structured and robust approach to the planning and implementation of land treatments. The U.S. Geological Survey partnered with the Bureau of Land Management to create the Land Treatment Exploration Tool to facilitate adaptive management of land treatments . The Exploration Tool taps into a wealth of information about past treatments in the Land Treatment Digital Library (LTDL, https://www.usgs.gov/apps/ltdl ). The Exploration Tool is designed for use by resource managers during the land treatment planning stage. This tool summarizes environmental characteristics of planned treatment areas and facilitates adaptive management practices by comparing those characteristics to similar legacy treatments.

Fact Sheet↗