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The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
Browse more than 65,000 articles authored by our scientists over the past 100+ year history of the USGS and refine search by topic, location, year, and advanced search.
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Aqueously altered igneous rocks sampled on the floor of Jezero crater, Mars Aqueously altered igneous rocks sampled on the floor of Jezero crater, Mars
The Perseverance rover landed in Jezero crater, Mars, to investigate ancient lake and river deposits. We report observations of the crater floor, below the crater’s sedimentary delta, finding the floor consists of igneous rocks altered by water. The lowest exposed unit, informally named Séítah, is a coarsely crystalline olivine-rich rock, which accumulated at the base of a magma body. Fe...
Authors
K.A. Farley, K.M. Stack, D.L. Shuster, B.H.N. Horgan, J.A. Hurowitz, J. D. Tarnas, J.I. Simon, V.Z. Sun, E.L. Scheller, K.R. Moore, S.M. McLennan, P.M. Vasconcelos, R. C. Wiens, A.H. Treiman, L.E. Mayhew, O. Beyssac, T.V. Kizovski, N. J. Tosca, K.H. Williford, L.S. Crumpler, L.W. Beegle, J.F. Bell III, B.L. Ehlmann, Y. Liu, J.N. Maki, M. E. Schmidt, A.C. Allwood, H.E.F. Amundsen, R. Ghartia, T. Bosak, A.J. Brown, B. C. Clark, A. Cousin, O. Forni, Travis S.J. Gabriel, Y. Goreva, S. Gupta, S.-E. Hamran, C.D.K. Herd, K. Hickman-Lewis, J.R. Johnson, L.C. Kah, P. B. Kelemen, K.B. Kinch, L. Mandon, N. Mangold, C. Quantun-Nataf, M.S. Rice, P.S. Russell, S. Sharma, S. Siljestroem, A. Steele, R. Sullivan, M. Wadhwa, B. P. Weiss, A.J. Williams, B.V. Wogsland, P.A. Willis, T.A. Acosta-Maeda, B. Peck, K. Benzerara, S. Bernard, A.S. Burton, E. L. Cardarelli, B. Chide, Elise Clavé, E.A. Cloutis, A.D. Czaja, V. Debaille, E. Dehouck, A.G. Fairen, D.T. Flannery, S.Z. Fleron, T. Fouchet, J. Frydenvang, B.J. Garczynski, E.F. Gibbons, E.M. Hausrath, A.G. Hayes, J. Henneke, J.L. Jorgensen, E.M. Kelly, J. Lasue, Stéphane Le Mouélic, J. M. Madariaga, S. Maurice, M. Merusi, P. #NAME? Meslin, S.M. Milkovich, C.C. Million, R.C. Moeller, J.I. Nunez, A.M. Ollila, G. Paar, D.A. Paige, D.A.K. Pedersen, P. Pilleri, C. Pilorget, P.C. Pinet, J.W. Rice Jr., C. Royer, V. Sautter, M. Schulte, M. A. Sephton, S.K. Sharma, S.F. Sholes, N. Spanovich, M. St. Clair, C.D. Tate, K. Uckert, S.J. VanBommel, A.G. Yanchilina, M. #NAME? Zorzano
Methods for robust estimates of tree biomass from pollen accumulation rates: Quantifying paleoecological reconstruction uncertainty Methods for robust estimates of tree biomass from pollen accumulation rates: Quantifying paleoecological reconstruction uncertainty
Pollen accumulation rates (PAR, grains cm–2 year–1) have been shown to be a reliable but methodologically complex bioproxy for quantitative reconstruction of past tree abundance. In a prior study, we found that the PARs of major tree taxa – Pseudotsuga, Pinus, Notholithocarpus, and the pollen group TC (Taxaceae and Cupressaceae families) – were robust and precise estimators of...
Authors
Clarke Alexandra Knight, John J. Battles, M. Jane Bunting, Marie Rhondelle Champagne, James A. Wanket, David Wahl
Range-wide sources of variation in reproductive rates of northern spotted owls Range-wide sources of variation in reproductive rates of northern spotted owls
We conducted a range-wide investigation of the dynamics of site level reproductive rate of northern spotted owls using survey data from 11 study areas across the sub-species geographic range collected during 1993–2018. Our analytical approach accounted for imperfect detection of owl pairs and misclassification of successful reproduction (i.e., at least one young fledged) and contributed...
Authors
Jeremy T. Rockweit, Julianna M Jenkins, James E. Hines, James D. Nichols, Katie M. Dugger, Alan B. Franklin, Peter C. Carlson, William L. Kendall, Damon B. Lesmeister, Christopher McCafferty, Steven H. Ackers, L. Steven Andrews, Larissa Bailey, Jesse Burgher, Kenneth P. Burnham, Tara E. Chestnut, Mary M Conner, Raymond J. Davis, Krista E. Dilione, Eric D. Forsman, Elizabeth M. Glenn, Scott A. Gremel, Keith A. Hamm, Dale R. Herter, J. Mark Higley, Rob B. Horn, David W Lamphear, Trent L. McDonald, Janice A Reid, Carl J. Schwarz, David C. Simon, Stan G Sovern, James K. Swingle, David Wiens, Heather Wise, Charles B. Yackulic
Incorporating streambank wells in stream mass loading studies to more effectively identify sources of solutes in stream water Incorporating streambank wells in stream mass loading studies to more effectively identify sources of solutes in stream water
Stream synoptic sampling studies that include flow estimates derived from the stream tracer dilution method are now commonly performed to identify sources and processes controlling solute transport to streams. However, a limitation of this mass-loading approach is its inability to identify the side of the stream on which a source is located in the common case where loading is largely...
Authors
Andrew H. Manning, Robert L. Runkel, Jean M. Morrison, Richard B. Wanty, Katherine Walton-Day
Stakeholder engagement to guide decision-relevant water data delivery Stakeholder engagement to guide decision-relevant water data delivery
Water resources management and policy making require access to reliable scientific data. However, water managers may need to overcome various obstacles to accessing data. For example, insufficient technological infrastructures, low data literacy, and data format complexities often inhibit data user access. Thus, it is imperative to include stakeholders in the design of data delivery...
Authors
Diana Restrepo-Osorio, Amanda D. Stoltz, Nicole M. Herman-Mercer
Tracing the sources and depositional history of mercury to coastal northeastern U.S. lakes Tracing the sources and depositional history of mercury to coastal northeastern U.S. lakes
Mercury (Hg) deposition was reconstructed in sediment cores from lakes in two coastal U.S. National Parks: Acadia National Park (ANP) and Cape Cod National Seashore (CCNS), to fill an important spatial gap in Hg deposition records and to explore changing sources of Hg and processes affecting Hg accumulation in these coastal sites. Recent Hg deposition chronology was assessed using (1) a...
Authors
Vivien F. Taylor, Joshua D. Landis, Sarah E. Janssen
Trace elements in olivine fingerprint the source of 2018 magmas and shed light on explosive-effusive eruption cycles at Kīlauea Volcano Trace elements in olivine fingerprint the source of 2018 magmas and shed light on explosive-effusive eruption cycles at Kīlauea Volcano
Understanding magma genesis and the evolution of intensive parameters (temperature, pressure, composition, degree of melting) in the mantle source of highly active volcanic systems is crucial for interpreting magma supply changes over time and recognizing cyclic behavior to anticipate future volcanic behavior. Major and trace elements in olivine are commonly used to study variations in...
Authors
Adrien Mourey, Thomas Shea, Kendra J. Lynn, Allan Lerner, Sarah Lambart, Fidel Costa, Jeffrey Oalmann, R. Lopaka Lee, Cheryl Gansecki
Variation in within-host replication kinetics among virus genotypes provides evidence of specialist and generalist infection strategies across three salmonid host species Variation in within-host replication kinetics among virus genotypes provides evidence of specialist and generalist infection strategies across three salmonid host species
Theory of the evolution of pathogen specialization suggests that a specialist pathogen gains high fitness in one host, but this comes with fitness loss in other hosts. By contrast, a generalist pathogen does not achieve high fitness in any host, but gains ecological fitness by exploiting different hosts, and has higher fitness than specialists in nonspecialized hosts. As a result...
Authors
David James Páez, Douglas G. McKenney, Maureen K. Purcell, Kerry A. Naish, Gael Kurath
Forecasting and communicating the dispersion and fallout of ash during volcanic eruptions: lessons from the September 20, 2020 eruptive pulse at Sangay volcano, Ecuador Forecasting and communicating the dispersion and fallout of ash during volcanic eruptions: lessons from the September 20, 2020 eruptive pulse at Sangay volcano, Ecuador
Volcanic ash is a hazard to human health and activities. Accurate and timely forecasts coupled with effective communication about the dispersion and fallout of volcanic ash during explosive events are essential to reduce impacts on local communities and limit economic losses. In this study, we present the first detailed description of an eruptive pulse at Sangay volcano and its eruption...
Authors
Benjamin Bernard, Pablo Samaniego, Larry G. Mastin, Stephen Hernandez, Gerardo Pino, Jamie Kibler, Marjorie Encalada, Silvano Hidalgo, Nicole Vizuete
Recent climate change has driven divergent hydrological shifts in high-latitude peatlands Recent climate change has driven divergent hydrological shifts in high-latitude peatlands
High-latitude peatlands are changing rapidly in response to climate change, including permafrost thaw. Here, we reconstruct hydrological conditions since the seventeenth century using testate amoeba data from 103 high-latitude peat archives. We show that 54% of the peatlands have been drying and 32% have been wetting over this period, illustrating the complex ecohydrological dynamics of...
Authors
Hui Zhang, Minna Valiranta, Graeme T. Swindles, Marco Aquino-Lopez, Donal Mullan, Ning Tan, Matthew Amesbury, Kirill Babeshko, Kunshan Bao, Anatoly Bobrov, Viktor Chernyshov, Marissa A. Davies, Andrei-Cosmin Diaconu, Angelica Feurdean, Sarah A. Finkelstein, Michelle Garneau, Zhengtang Guo, Miriam C. Jones, Martin Kay, Eric S. Klein, Maruisz Lamentowicz, Gabriel Magnan, Katarzyna Marcisz, Natalia Mazei, Yuri Mazei, Richard Payne, Nicolas Pelletier, Sanna Piilo, Steve Pratte, Thomas P. Roland, Damir Saldaev, William Shotyk, Thomas G. Sim, Thomas J Sloan, Michal Slowinski, Julie Talbot, Liam Taylor, Andrey N. Tsyganov, Sebastian Wetterich, Wei Xing, Yan Zhao
Democratizing macroecology: Integrating unoccupied aerial systems with the National Ecological Observatory Network Democratizing macroecology: Integrating unoccupied aerial systems with the National Ecological Observatory Network
Macroecology research seeks to understand ecological phenomena with causes and consequences that accumulate, interact, and emerge across scales spanning several orders of magnitude. Broad-extent, fine-grain information (i.e., high spatial resolution data over large areas) is needed to adequately capture these cross-scale phenomena, but these data have historically been costly to acquire...
Authors
Michael J. Koontz, Victoria Mary Scholl, Anna I Spiers, Megan E Cattau, John Adler, Joseph McGlinchy, Tristan Goulden, Brett A Melbourne, Jennifer K. Balch
Predicting physical and geomorphic habitat associated with historical lake whitefish and cisco spawning locations in Lakes Erie and Ontario Predicting physical and geomorphic habitat associated with historical lake whitefish and cisco spawning locations in Lakes Erie and Ontario
The Great Lakes basin was historically populated by multiple, coevolved coregonine species, but much of that diversity has been lost. In Lakes Erie and Ontario, both lake whitefish (Coregonus clupeaformis) and cisco (Coregonus artedi) occurred in high numbers before habitat degradation, overfishing, invasive species, and other factors caused significant declines. There is growing...
Authors
Hannah M Schaefer, Andrew Edgar Honsey, David Bunnell, Brian Weidel, Robin DeBruyne, James S. Diana, Dimitry Gorsky, Edward F. Roseman