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Filter Total Items: 2,153
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Year Published: 2017

Connecting the dots: Preprocessing Apollo 15 panoramic camera images for photogrammetric control

No abstract available.

Edmundson, Kenneth L.; Archinal, Brent A.; Becker, Tammy L.; Mapel, J.A.; Robinson, Mark S.; Shepherd, M.R.

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Year Published: 2017

Characterization of the quality of water, bed sediment, and fish in Mittry Lake, Arizona, 2014–15

Water, bed-sediment, and fish sampling was conducted in Mittry Lake, Arizona, in 2014–15 to establish current water-quality conditions of the lake. The parameters of temperature, dissolved-oxygen concentration, specific conductance, and alkalinity were measured in the field. Water samples were collected and analyzed for dissolved major ions,...

Hermosillo, Edyth; Coes, Alissa L.
Hermosillo, E., and Coes, A.L., 2017, Characterization of the quality of water, bed sediment, and fish in Mittry Lake, Arizona, 2014–15: U.S. Geological Survey Scientific Investigations Report 2017-5008, 13 p., https://doi.org/10.3133/sir20175008.

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Year Published: 2017

Recalibration of the Mars Science Laboratory ChemCam instrument with an expanded geochemical database

The ChemCam Laser-Induced Breakdown Spectroscopy (LIBS) instrument onboard the Mars Science Laboratory (MSL) rover Curiosity has obtained > 300,000 spectra of rock and soil analysis targets since landing at Gale Crater in 2012, and the spectra represent perhaps the largest publicly-available LIBS datasets. The compositions of the major...

Clegg, Samuel M.; Wiens, Roger C.; Anderson, Ryan; Forni, Olivier; Frydenvang, Jens; Lasue, Jeremie; Cousin, Agnes; Payre, Valerie; Boucher, Tommy; Dyar, M. Darby; McLennan, Scott M.; Morris, Richard V.; Graff, Trevor G.; Mertzman, Stanley A; Ehlmann, Bethany L.; Belgacem, Ines; Newsom, Horton E.; Clark, Ben C.; Melikechi, Noureddine; Mezzacappa, Alissa; McInroy, Rhonda E.; Martinez, Ronald; Gasda, Patrick J.; Gasnault, Olivier; Maurice, Sylvestre
Samuel M. Clegg, Roger C. Wiens, Ryan Anderson, Olivier Forni, Jens Frydenvang, Jeremie Lasue, Agnes Cousin, Valérie Payré, Tommy Boucher, M. Darby Dyar, Scott M. McLennan, Richard V. Morris, Trevor G. Graff, Stanley A. Mertzman, Bethany L. Ehlmann, Ines Belgacem, Horton Newsom, Ben C. Clark, Noureddine Melikechi, Alissa Mezzacappa, Rhonda E. McInroy, Ronald Martinez, Patrick Gasda, Olivier Gasnault, Sylvestre Maurice, Recalibration of the Mars Science Laboratory ChemCam instrument with an expanded geochemical database, Spectrochimica Acta Part B: Atomic Spectroscopy, Volume 129, 1 March 2017, Pages 64-85

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Year Published: 2017

Subsurface volatile content of martian double-layer ejecta (DLE) craters

Excess ice is widespread throughout the martian mid-latitudes, particularly in Arcadia Planitia, where double-layer ejecta (DLE) craters also tend to be abundant. In this region, we observe the presence of thermokarstically-expanded secondary craters that likely form from impacts that destabilize a subsurface layer of excess ice, which...

Viola, Donna; McEwen, Alfred S.; Dundas, Colin M.; Byrne, Shane
Viola, D., McEwen, A. S., Byrne, S., Dundas, C. M., 2017. Subsurface volatile content of Martian double-layer ejecta (DLE) craters. Icarus 284, 325-343.

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Year Published: 2017

Geochemistry and hydrology of perched groundwater springs: assessing elevated uranium concentrations at Pigeon Spring relative to nearby Pigeon Mine, Arizona (USA)

The processes that affect water chemistry as the water flows from recharge areas through breccia-pipe uranium deposits in the Grand Canyon region of the southwestern United States are not well understood. Pigeon Spring had elevated uranium in 1982 (44 μg/L), compared to other perched springs (2.7–18 μg/L), prior to mining operations at the nearby...

Beisner, Kimberly R.; Paretti, Nicholas V.; Tillman, Fred; Naftz, David L.; Bills, Donald; Walton-Day, Katie; Gallegos, Tanya J.
Beisner, K.R., Paretti, N.V., Tillman, F.D., Naftz, D.L., Bills, D.J., Walton-Day, K., and Gallegos, T.J., 2017, Geochemistry and hydrology of perched groundwater springs: assessing elevated uranium concentrations at Pigeon Spring relative to nearby Pigeon Mine, Arizona (USA), Hydrogeology Journal, vol. 25, issue 2, p. 539-556.

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Year Published: 2017

Long-term fish monitoring in large rivers: Utility of “benchmarking” across basins

In business, benchmarking is a widely used practice of comparing your own business processes to those of other comparable companies and incorporating identified best practices to improve performance. Biologists and resource managers designing and conducting monitoring programs for fish in large river systems tend to focus on single river basins or...

Ward, David L.; Casper, Andrew F.; Counihan, Timothy D.; Bayer, Jennifer M.; Waite, Ian R.; Kosovich, John J.; Chapman, Colin; Irwin, Elise R.; Sauer, Jennifer S.; Ickes, Brian; McKerrow, Alexa J.
Ward, D.L., Casper, A.F., Counihan, T.D., Bayer, J.M., Waite, I.R., Kosovich, J.J., Chapman, C.G., Irwin, E.R., Sauer, J.S., Iches, B.S., and McKerrow, A.J., 2017,Long-Term Fish Monitoring in Large Rivers: Utility of “Benchmarking” across Basins: Fisheries, no. 42, v. 2, p

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Year Published: 2017

Aridity increases below-ground niche breadth in grass communities

Aridity is an important environmental filter in the assembly of plant communities worldwide. The extent to which root traits mediate responses to aridity, and how they are coordinated with leaf traits, remains unclear. Here, we measured variation in root tissue density (RTD), specific root length (SRL), specific leaf area (SLA), and seed size...

Butterfield, Bradley J.; Bradford, John B.; Munson, Seth M.; Gremer, Jennifer R.
Butterfield, B.J., Bradford, J.B., Munson, S.M., Gremer, J.R., 2017, Aridity increases below-ground niche breadth in grass communities: Plant Ecology, v. (online), http://dx.doi.org/10.1007/s11258-016-0696-4 and http://link.springer.com/article/10.1007/s11258-016-0696-4.

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Year Published: 2017

Differential responses of dinitrogen fixation, diazotrophic cyanobacteria and ammonia oxidation reveal a potential warming-induced imbalance of the N-cycle in biological soil crusts

N2 fixation and ammonia oxidation (AO) are the two most important processes in the nitrogen (N) cycle of biological soil crusts (BSCs). We studied the short-term response of acetylene reduction assay (ARA) rates, an indicator of potential N2 fixation, and AO rates to temperature (T, -5°C to 35°C) in BSC of different successional stages along the...

Zhou, Xiaobing; Smith, Hilda J.; Giraldo Silva, Ana; Belnap, Jayne; Garcia-Pichel, Ferran

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Year Published: 2017

Climate change reduces extent of temperate drylands and intensifies drought in deep soils

Drylands cover 40% of the global terrestrial surface and provide important ecosystem services. While drylands as a whole are expected to increase in extent and aridity in coming decades, temperature and precipitation forecasts vary by latitude and geographic region suggesting different trajectories for tropical, subtropical, and temperate drylands...

Schlaepfer, Daniel R.; Bradford, John B.; Lauenroth, William K.; Munson, Seth M.; Tietjen, Britta; Hall, Sonia A.; Wilson, Scott D.; Duniway, Michael C.; Jia, Gensuo; Pyke, David A.; Lkhagva, Ariuntsetseg; Jamiyansharav, Khishigbayar
Schlaepfer, D.R., Bradford, J.B., Lauenroth, W.K., Munson, S.M., Tietjen, B., Hall, S.A., Wilson, S.D., Duniway, M.C., Jia, G., Pyke, D.A., Lkhagva, A., and Khishigbayar, J., 2017, Climate change reduces extent of temperate drylands and intensifies drought in deep soils: Nature Communications, no. 8, http://www.nature.com/articles/ncomms14196#abstract and http://dx.doi.org/10.1038/ncomms14196.

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Year Published: 2017

Chemistry of diagenetic features analyzed by ChemCam at Pahrump Hills, Gale crater, Mars

The Curiosity rover's campaign at Pahrump Hills provides the first analyses of lower Mount Sharp strata. Here we report ChemCam elemental composition of a diverse assemblage of post-depositional features embedded in, or cross-cutting, the host rock. ChemCam results demonstrate their compositional diversity, especially compared to the surrounding...

Nachon, Marion; Mangold, Nicolas; Forni, Olivier; Kah, Linda C.; Cousin, Agnes; Wiens, Roger C.; Anderson, Ryan; Blaney, Diana L.; Blank, Jen G.; Calef, Fred J.; Clegg, Samuel M.; Fabre, Cecile; Fisk, Martin R.; Gasnault, Olivier; Grotzinger, John P.; Kronyak, Rachel; Lanza, Nina L.; Lasue, Jeremie; Le Deit, Laetitia; Le Mouelic, Stephane; Maurice, Sylvestre; Meslin, Pierre-Yves; Oehler, D. Z.; Payre, Valerie; Rapin, William; Schroder, Susanne; Stack, Katherine M.; Sumner, Dawn
Nachon, M., Mangold, N., Forni, O., Kah, L.C., Cousin, A., Wiens, R.C., Anderson, R., Blaney, D., Blank, J.G., Calef, F., Clegg, S.M., Fabre, C., Fisk, M.R., Gasnault, O., Grotzinger, J.P., Kronyak, R., Lanza, N.L., Lasue, J., Deit, L.L., Mouélic, S.L., Maurice, S., Meslin, P.-Y., Oehler, D.Z., Payré, V., Rapin, W., Schröder, S., Stack, K., Sumner, D., 2017. Chemistry of diagenetic features analyzed by ChemCam at Pahrump Hills, Gale crater, Mars. Icarus 281, 121–136. doi:10.1016/j.icarus.2016.08.026

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Year Published: 2017

Ecosystem implications of conserving endemic versus eradicating introduced large herbivores in the Galapagos Archipelago

Restoration of damaged ecosystems through invasive species removal and native species conservation is an increasingly common practice in biodiversity conservation. Estimating the degree of ecosystem response attributable specifically to eradication of exotic herbivores versus restoration of native herbivores is often difficult and is complicated...

Bastille-Rousseau, Guillaume; Gibbs, James P.; Campbell, Karl; Yackulic, Charles B.; Blake, Stephen
Bastille-Rousseau, G., Gibbs, J.P., Campbell, K, Yackulic, C.B., and Blake, S., 2017, Ecosystem implications of conserving endemic versus eradicating introduced large herbivores in the Galapagos Archipelago: Biological Conservation, n. 209, p. 1-10, http://dx.doi.org/10.1016/j.biocon.2017.02.015

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Year Published: 2017

Improved accuracy in quantitative laser-induced breakdown spectroscopy using sub-models

Accurate quantitative analysis of diverse geologic materials is one of the primary challenges faced by the Laser-Induced Breakdown Spectroscopy (LIBS)-based ChemCam instrument on the Mars Science Laboratory (MSL) rover. The SuperCam instrument on the Mars 2020 rover, as well as other LIBS instruments developed for geochemical analysis on Earth or...

Anderson, Ryan; Clegg, Samuel M.; Frydenvang, Jens; Wiens, Roger C.; McLennan, Scott M.; Morris, Richard V.; Ehlmann, Bethany L.; Dyar, M. Darby
Clegg, S.M., Wiens, R.C., Anderson, R., Forni, O., Frydenvang, J., Lasue, J., Cousin, A., Payré, V., Boucher, T., Dyar, M.D., McLennan, S.M., Morris, R.V., Graff, T.G., Mertzman, S.A., Ehlmann, B.L., Belgacem, I., Newsom, H., Clark, B.C., Melikechi, N., Mezzacappa, A., McInroy, R.E., Martinez, R., Gasda, P., Gasnault, O., Maurice, S., 2017. Recalibration of the Mars Science Laboratory ChemCam instrument with an expanded geochemical database. Spectrochimica Acta Part B: Atomic Spectroscopy 129, 64–85. doi:10.1016/j.sab.2016.12.003

Nine USGS Science Centers are administered by the Pacific Regional office, which is headquartered in Sacramento, California.