Phyllosilicates, a class of hydrous mineral first definitively identified on Mars by the OMEGA (Observatoire pour la Mineralogie, L’Eau, les Glaces et l’Activitié) instrument1,2, preserve a record of the interaction of water with rocks on Mars. Global mapping showed that phyllosilicates are widespread but are apparently restricted to ancient terrains and a relatively narrow range of mineralogy (Fe/Mg and Al smectite clays). This was interpreted to indicate that phyllosilicate formation occurred during the Noachian (the earliest geological era of Mars), and that the conditions necessary for phyllosilicate formation (moderate to high pH and high water activity3) were specific to surface environments during the earliest era of Mars’s history4. Here we report results from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM)4 of phyllosilicate-rich regions. We expand the diversity of phyllosilicate mineralogy with the identification of kaolinite, chlorite and illite or muscovite, and a new class of hydrated silicate (hydrated silica). We observe diverse Fe/Mg-OH phyllosilicates and find that smectites such as nontronite and saponite are the most common, but chlorites are also present in some locations. Stratigraphic relationships in the Nili Fossae region show olivine-rich materials overlying phyllosilicate-bearing units, indicating the cessation of aqueous alteration before emplacement of the olivine-bearing unit. Hundreds of detections of Fe/Mg phyllosilicate in rims, ejecta and central peaks of craters in the southern highland Noachian cratered terrain indicate excavation of altered crust from depth. We also find phyllosilicate in sedimentary deposits clearly laid by water. These results point to a rich diversity of Noachian environments conducive to habitability.
","language":"English","publisher":"Nature Publishing Group","doi":"10.1038/nature07097","usgsCitation":"Mustard, J., Murchie, S., Pelkey, S., Ehlmann, B., Milliken, R., Grant, J.A., Bibring, J., Poulet, F., Bishop, J., Dobrea, E., Roach, L., Seelos, F., Arvidson, R., Wiseman, S., Green, R., Hash, C., Humm, D., Malaret, E., McGovern, J., Seelos, K., Clancy, T., Clark, R., des Marais, D., Izenberg, N., Knudson, A., Langevin, Y., Martin, T., McGuire, P., Morris, R., Robinson, M., Roush, T., Smith, M., Swayze, G., Taylor, H., Titus, T., and Wolff, M., 2008, Hydrated silicate minerals on Mars observed by the Mars Reconnaissance Orbiter CRISM instrument: Nature, v. 454, no. 7202, p. 305-309, https://doi.org/10.1038/nature07097.","productDescription":"5 p.","startPage":"305","endPage":"309","costCenters":[],"links":[{"id":203645,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"454","issue":"7202","noUsgsAuthors":false,"publicationDate":"2008-07-01","publicationStatus":"PW","scienceBaseUri":"4f4e4a51e4b07f02db62a35e","contributors":{"authors":[{"text":"Mustard, J.F.","contributorId":91605,"corporation":false,"usgs":true,"family":"Mustard","given":"J.F.","email":"","affiliations":[],"preferred":false,"id":345561,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Murchie, S.L.","contributorId":7369,"corporation":false,"usgs":true,"family":"Murchie","given":"S.L.","email":"","affiliations":[],"preferred":false,"id":345531,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Pelkey, S.M.","contributorId":8599,"corporation":false,"usgs":true,"family":"Pelkey","given":"S.M.","email":"","affiliations":[],"preferred":false,"id":345532,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Ehlmann, B.L.","contributorId":107837,"corporation":false,"usgs":true,"family":"Ehlmann","given":"B.L.","email":"","affiliations":[],"preferred":false,"id":345566,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Milliken, R.E.","contributorId":98022,"corporation":false,"usgs":true,"family":"Milliken","given":"R.E.","email":"","affiliations":[],"preferred":false,"id":345564,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Grant, J. A.","contributorId":28334,"corporation":false,"usgs":true,"family":"Grant","given":"J.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":345536,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Bibring, J.-P.","contributorId":86083,"corporation":false,"usgs":true,"family":"Bibring","given":"J.-P.","email":"","affiliations":[],"preferred":false,"id":345559,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Poulet, F.","contributorId":61551,"corporation":false,"usgs":true,"family":"Poulet","given":"F.","email":"","affiliations":[],"preferred":false,"id":345551,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Bishop, J.","contributorId":70905,"corporation":false,"usgs":true,"family":"Bishop","given":"J.","email":"","affiliations":[],"preferred":false,"id":345555,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Dobrea, E. N.","contributorId":23677,"corporation":false,"usgs":true,"family":"Dobrea","given":"E. N.","affiliations":[],"preferred":false,"id":345534,"contributorType":{"id":1,"text":"Authors"},"rank":10},{"text":"Roach, L.","contributorId":62334,"corporation":false,"usgs":true,"family":"Roach","given":"L.","email":"","affiliations":[],"preferred":false,"id":345552,"contributorType":{"id":1,"text":"Authors"},"rank":11},{"text":"Seelos, F.","contributorId":34635,"corporation":false,"usgs":true,"family":"Seelos","given":"F.","affiliations":[],"preferred":false,"id":345540,"contributorType":{"id":1,"text":"Authors"},"rank":12},{"text":"Arvidson, R. E.","contributorId":46666,"corporation":false,"usgs":true,"family":"Arvidson","given":"R. E.","affiliations":[],"preferred":false,"id":345543,"contributorType":{"id":1,"text":"Authors"},"rank":13},{"text":"Wiseman, S.","contributorId":40711,"corporation":false,"usgs":true,"family":"Wiseman","given":"S.","email":"","affiliations":[],"preferred":false,"id":345542,"contributorType":{"id":1,"text":"Authors"},"rank":14},{"text":"Green, R.","contributorId":88858,"corporation":false,"usgs":true,"family":"Green","given":"R.","affiliations":[],"preferred":false,"id":345560,"contributorType":{"id":1,"text":"Authors"},"rank":15},{"text":"Hash, C.","contributorId":59927,"corporation":false,"usgs":true,"family":"Hash","given":"C.","email":"","affiliations":[],"preferred":false,"id":345550,"contributorType":{"id":1,"text":"Authors"},"rank":16},{"text":"Humm, D.","contributorId":28346,"corporation":false,"usgs":true,"family":"Humm","given":"D.","email":"","affiliations":[],"preferred":false,"id":345537,"contributorType":{"id":1,"text":"Authors"},"rank":17},{"text":"Malaret, E.","contributorId":84487,"corporation":false,"usgs":true,"family":"Malaret","given":"E.","email":"","affiliations":[],"preferred":false,"id":345557,"contributorType":{"id":1,"text":"Authors"},"rank":18},{"text":"McGovern, J.A.","contributorId":59163,"corporation":false,"usgs":true,"family":"McGovern","given":"J.A.","email":"","affiliations":[],"preferred":false,"id":345549,"contributorType":{"id":1,"text":"Authors"},"rank":19},{"text":"Seelos, K.","contributorId":96813,"corporation":false,"usgs":true,"family":"Seelos","given":"K.","email":"","affiliations":[],"preferred":false,"id":345563,"contributorType":{"id":1,"text":"Authors"},"rank":20},{"text":"Clancy, T.","contributorId":33439,"corporation":false,"usgs":true,"family":"Clancy","given":"T.","email":"","affiliations":[],"preferred":false,"id":345539,"contributorType":{"id":1,"text":"Authors"},"rank":21},{"text":"Clark, R.","contributorId":100780,"corporation":false,"usgs":true,"family":"Clark","given":"R.","affiliations":[],"preferred":false,"id":345565,"contributorType":{"id":1,"text":"Authors"},"rank":22},{"text":"des Marais, D.","contributorId":48293,"corporation":false,"usgs":true,"family":"des Marais","given":"D.","affiliations":[],"preferred":false,"id":345544,"contributorType":{"id":1,"text":"Authors"},"rank":23},{"text":"Izenberg, N.","contributorId":56777,"corporation":false,"usgs":true,"family":"Izenberg","given":"N.","affiliations":[],"preferred":false,"id":345547,"contributorType":{"id":1,"text":"Authors"},"rank":24},{"text":"Knudson, A.","contributorId":86082,"corporation":false,"usgs":true,"family":"Knudson","given":"A.","email":"","affiliations":[],"preferred":false,"id":345558,"contributorType":{"id":1,"text":"Authors"},"rank":25},{"text":"Langevin, Y.","contributorId":24900,"corporation":false,"usgs":true,"family":"Langevin","given":"Y.","email":"","affiliations":[],"preferred":false,"id":345535,"contributorType":{"id":1,"text":"Authors"},"rank":26},{"text":"Martin, T.","contributorId":58375,"corporation":false,"usgs":true,"family":"Martin","given":"T.","affiliations":[],"preferred":false,"id":345548,"contributorType":{"id":1,"text":"Authors"},"rank":27},{"text":"McGuire, P.","contributorId":65039,"corporation":false,"usgs":true,"family":"McGuire","given":"P.","email":"","affiliations":[],"preferred":false,"id":345553,"contributorType":{"id":1,"text":"Authors"},"rank":28},{"text":"Morris, Robert","contributorId":70723,"corporation":false,"usgs":true,"family":"Morris","given":"Robert","affiliations":[],"preferred":false,"id":345554,"contributorType":{"id":1,"text":"Authors"},"rank":29},{"text":"Robinson, M.","contributorId":50272,"corporation":false,"usgs":true,"family":"Robinson","given":"M.","affiliations":[],"preferred":false,"id":345545,"contributorType":{"id":1,"text":"Authors"},"rank":30},{"text":"Roush, T.","contributorId":76445,"corporation":false,"usgs":true,"family":"Roush","given":"T.","affiliations":[],"preferred":false,"id":345556,"contributorType":{"id":1,"text":"Authors"},"rank":31},{"text":"Smith, M.","contributorId":32658,"corporation":false,"usgs":false,"family":"Smith","given":"M.","affiliations":[],"preferred":false,"id":345538,"contributorType":{"id":1,"text":"Authors"},"rank":32},{"text":"Swayze, G. 0000-0002-1814-7823","orcid":"https://orcid.org/0000-0002-1814-7823","contributorId":55131,"corporation":false,"usgs":true,"family":"Swayze","given":"G.","affiliations":[],"preferred":false,"id":345546,"contributorType":{"id":1,"text":"Authors"},"rank":33},{"text":"Taylor, H.","contributorId":39920,"corporation":false,"usgs":false,"family":"Taylor","given":"H.","affiliations":[{"id":27814,"text":"Johns Hopkins University Applied Physics Lab.","active":true,"usgs":false}],"preferred":false,"id":345541,"contributorType":{"id":1,"text":"Authors"},"rank":34},{"text":"Titus, T.","contributorId":92787,"corporation":false,"usgs":true,"family":"Titus","given":"T.","email":"","affiliations":[],"preferred":false,"id":345562,"contributorType":{"id":1,"text":"Authors"},"rank":35},{"text":"Wolff, M.","contributorId":19683,"corporation":false,"usgs":true,"family":"Wolff","given":"M.","affiliations":[],"preferred":false,"id":345533,"contributorType":{"id":1,"text":"Authors"},"rank":36}]}} ,{"id":70000350,"text":"70000350 - 2008 - Distribution and variability of redox zones controlling spatial variability of arsenic in the Mississippi River Valley alluvial aquifer, southeastern Arkansas","interactions":[],"lastModifiedDate":"2012-03-08T17:16:37","indexId":"70000350","displayToPublicDate":"2010-09-28T23:09:22","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2233,"text":"Journal of Contaminant Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Distribution and variability of redox zones controlling spatial variability of arsenic in the Mississippi River Valley alluvial aquifer, southeastern Arkansas","docAbstract":"Twenty one of 118 irrigation water wells in the shallow (25-30??m thick) Mississippi River Valley alluvial aquifer in the Bayou Bartholomew watershed, southeastern Arkansas had arsenic (As) concentrations (< 0.5 to 77????g/L) exceeding 10????g/L. Sediment and groundwater samples were collected and analyzed from the sites of the highest, median, and lowest concentrations of As in groundwater in the alluvial aquifers located at Jefferson County, Arkansas. A traditional five-step sequential extraction was performed to differentiate the exchangeable, carbonate, amorphous Fe and Mn oxide, organic, and hot HNO3-leachable fraction of As and other compounds in sediments. The Chao reagent (0.25??M hydroxylamine hydrochloride in 0.25??M HCl) removes amorphous Fe and Mn oxides and oxyhydroxides (present as coatings on grains and amorphous minerals) by reductive dissolution and is a measure of reducible Fe and Mn in sediments. The hot HNO3 extraction removes mostly crystalline metal oxides and all other labile forms of As. Significant total As (20%) is complexed with amorphous Fe and Mn oxides in sediments. Arsenic abundance is not significant in carbonates or organic matter. Significant (40-70????g/kg) exchangeable As is only present at shallow depth (0-1??m below ground surface). Arsenic is positively correlated to Fe extracted by Chao reagent (r = 0.83) and hot HNO3 (r = 0.85). Arsenic extracted by Chao reagent decreases significantly with depth as compared to As extracted by hot HNO3. Fe (II)/Fe (the ratio of Fe concentration in the extracts of Chao reagent and hot HNO3) is positively correlated (r = 0.76) to As extracted from Chao reagent. Although Fe (II)/Fe increases with depth, the relative abundance of reducible Fe decreases noticeably with depth. The amount of reducible Fe, as well as As complexed to amorphous Fe and Mn oxides and oxyhydroxides decreases with depth. Possible explanations for the decrease in reducible Fe and its complexed As with depth include historic flushing of As and Fe from hydrous ferric oxides (HFO) by microbially-mediated reductive dissolution and aging of HFO to crystalline phases. Hydrogeochemical data suggests that the groundwater in the area falls in the mildly reducing (suboxic) to relatively highly reducing (anoxic) zone, and points to reductive dissolution of HFO as the dominant As release mechanism. Spatial variability of gypsum solubility and simultaneous SO42- reduction with co-precipitation of As and sulfide is an important limiting process controlling the concentration of As in groundwater in the area. ?? 2008 Elsevier B.V. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Contaminant Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/j.jconhyd.2008.03.001","issn":"01697722","usgsCitation":"Sharif, M., Davis, R., Steele, K., Kim, B., Hays, P., Kresse, T., and Fazio, J., 2008, Distribution and variability of redox zones controlling spatial variability of arsenic in the Mississippi River Valley alluvial aquifer, southeastern Arkansas: Journal of Contaminant Hydrology, v. 99, no. 1-4, p. 49-67, https://doi.org/10.1016/j.jconhyd.2008.03.001.","startPage":"49","endPage":"67","costCenters":[],"links":[{"id":18811,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.jconhyd.2008.03.001"},{"id":203526,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"99","issue":"1-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a80e4b07f02db649370","contributors":{"authors":[{"text":"Sharif, M.U.","contributorId":106243,"corporation":false,"usgs":true,"family":"Sharif","given":"M.U.","email":"","affiliations":[],"preferred":false,"id":345525,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Davis, R.K.","contributorId":85307,"corporation":false,"usgs":true,"family":"Davis","given":"R.K.","email":"","affiliations":[],"preferred":false,"id":345523,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Steele, K.F.","contributorId":50270,"corporation":false,"usgs":true,"family":"Steele","given":"K.F.","email":"","affiliations":[],"preferred":false,"id":345520,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Kim, B.","contributorId":93173,"corporation":false,"usgs":true,"family":"Kim","given":"B.","email":"","affiliations":[],"preferred":false,"id":345524,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Hays, P.D.","contributorId":64682,"corporation":false,"usgs":true,"family":"Hays","given":"P.D.","email":"","affiliations":[],"preferred":false,"id":345522,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Kresse, T.M.","contributorId":107019,"corporation":false,"usgs":true,"family":"Kresse","given":"T.M.","email":"","affiliations":[],"preferred":false,"id":345526,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Fazio, J.A.","contributorId":63135,"corporation":false,"usgs":true,"family":"Fazio","given":"J.A.","email":"","affiliations":[],"preferred":false,"id":345521,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}} ,{"id":70000326,"text":"70000326 - 2008 - Global daily reference evapotranspiration modeling and evaluation","interactions":[],"lastModifiedDate":"2017-04-03T12:50:52","indexId":"70000326","displayToPublicDate":"2010-09-28T23:09:22","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2529,"text":"Journal of the American Water Resources Association","active":true,"publicationSubtype":{"id":10}},"title":"Global daily reference evapotranspiration modeling and evaluation","docAbstract":"Accurate and reliable evapotranspiration (ET) datasets are crucial in regional water and energy balance studies. Due to the complex instrumentation requirements, actual ET values are generally estimated from reference ET values by adjustment factors using coefficients for water stress and vegetation conditions, commonly referred to as crop coefficients. Until recently, the modeling of reference ET has been solely based on important weather variables collected from weather stations that are generally located in selected agro-climatic locations. Since 2001, the National Oceanic and Atmospheric Administration’s Global Data Assimilation System (GDAS) has been producing six-hourly climate parameter datasets that are used to calculate daily reference ET for the whole globe at 1-degree spatial resolution. The U.S. Geological Survey Center for Earth Resources Observation and Science has been producing daily reference ET (ETo) since 2001, and it has been used on a variety of operational hydrological models for drought and streamflow monitoring all over the world. With the increasing availability of local station-based reference ET estimates, we evaluated the GDAS-based reference ET estimates using data from the California Irrigation Management Information System (CIMIS). Daily CIMIS reference ET estimates from 85 stations were compared with GDAS-based reference ET at different spatial and temporal scales using five-year daily data from 2002 through 2006. Despite the large difference in spatial scale (point vs. ∼100 km grid cell) between the two datasets, the correlations between station-based ET and GDAS-ET were very high, exceeding 0.97 on a daily basis to more than 0.99 on time scales of more than 10 days. Both the temporal and spatial correspondences in trend/pattern and magnitudes between the two datasets were satisfactory, suggesting the reliability of using GDAS parameter-based reference ET for regional water and energy balance studies in many parts of the world. While the study revealed the potential of GDAS ETo for large-scale hydrological applications, site-specific use of GDAS ETo in complex hydro-climatic regions such as coastal areas and rugged terrain may require the application of bias correction and/or disaggregation of the GDAS ETo using downscaling techniques.
","language":"English","publisher":"Wiley","doi":"10.1111/j.1752-1688.2008.00195.x","issn":"1093474X","usgsCitation":"Senay, G., Verdin, J., Lietzow, R., and Melesse, A.M., 2008, Global daily reference evapotranspiration modeling and evaluation: Journal of the American Water Resources Association, v. 44, no. 4, p. 969-979, https://doi.org/10.1111/j.1752-1688.2008.00195.x.","productDescription":"11 p.","startPage":"969","endPage":"979","costCenters":[{"id":222,"text":"Earth Resources Observation and Science (EROS) Center","active":true,"usgs":true}],"links":[{"id":203573,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":18793,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1111/j.1752-1688.2008.00195.x"}],"volume":"44","issue":"4","noUsgsAuthors":false,"publicationDate":"2008-07-25","publicationStatus":"PW","scienceBaseUri":"4f4e4abee4b07f02db674cf3","contributors":{"authors":[{"text":"Senay, G.B. 0000-0002-8810-8539","orcid":"https://orcid.org/0000-0002-8810-8539","contributorId":17741,"corporation":false,"usgs":true,"family":"Senay","given":"G.B.","affiliations":[],"preferred":false,"id":345447,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Verdin, J. P. 0000-0003-0238-9657","orcid":"https://orcid.org/0000-0003-0238-9657","contributorId":33033,"corporation":false,"usgs":true,"family":"Verdin","given":"J. P.","affiliations":[],"preferred":false,"id":345448,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lietzow, R.","contributorId":89648,"corporation":false,"usgs":true,"family":"Lietzow","given":"R.","email":"","affiliations":[],"preferred":false,"id":345450,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Melesse, Assefa M.","contributorId":45044,"corporation":false,"usgs":false,"family":"Melesse","given":"Assefa","email":"","middleInitial":"M.","affiliations":[{"id":7003,"text":"Deprtment of Earth & Environmental ECS 339, Florida Interational University","active":true,"usgs":false}],"preferred":false,"id":345449,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70000343,"text":"70000343 - 2008 - Landscape pattern of seed banks and anthropogenic impacts in forested wetlands of the northern Mississippi River Alluvial Valley","interactions":[],"lastModifiedDate":"2012-03-08T17:16:33","indexId":"70000343","displayToPublicDate":"2010-09-28T23:09:22","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1474,"text":"Écoscience","active":true,"publicationSubtype":{"id":10}},"title":"Landscape pattern of seed banks and anthropogenic impacts in forested wetlands of the northern Mississippi River Alluvial Valley","docAbstract":"Agricultural development on floodplains contributes to hydrologic alteration and forest fragmentation, which may alter landscape-level processes. These changes may be related to shifts in the seed bank composition of floodplain wetlands. We examined the patterns of seed bank composition across a floodplain watershed by looking at the number of seeds germinating per m2 by species in 60 farmed and intact forested wetlands along the Cache River watershed in Illinois. The seed bank composition was compared above and below a water diversion (position), which artificially subdivides the watershed. Position of these wetlands represented the most variability of Axis I in a Nonmetric Multidimensional Scaling (NMS) analysis of site environmental variables and their relationship to seed bank composition (coefficient of determination for Axis 1: r2 = 0.376; Pearson correlation of position to Axis 1: r = 0.223). The 3 primary axes were also represented by other site environmental variables, including farming status (farmed or unfarmed), distance from the mouth of the river, latitude, and longitude. Spatial analysis based on Mantel correlograms showed that both water-dispersed and wind/water-dispersed seed assemblages had strong spatial structure in the upper Cache (above the water diversion), bur the spatial structure of water-dispersed seed assemblage was diminished in the lower Cache (below the water diversion), which lost floodpulsing. Bearing analysis also Suggested that water-dispersal process had a stronger influence on the overall spatial pattern of seed assemblage in the upper Cache, while wind/water-dispersal process had a stronger influence in the lower Cache. An analysis of the landscapes along the river showed that the mid-lower Cache (below the water diversion) had undergone greater land cover changes associated with agriculture than did the upper Cache watershed. Thus, the combination of forest fragmentation and hydrologic changes in the surrounding landscape may have had an influence on the seed bank composition and spatial distribution of the seed banks of the Cache River watershed. Our study suggests that the spatial pattern of seed bank composition may be influenced by landscape-level factors and processes.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Ecoscience","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.2980/15-2-2882","issn":"11956860","usgsCitation":"Middleton, B., and Wu, X., 2008, Landscape pattern of seed banks and anthropogenic impacts in forested wetlands of the northern Mississippi River Alluvial Valley: Écoscience, v. 15, no. 2, p. 231-240, https://doi.org/10.2980/15-2-2882.","startPage":"231","endPage":"240","costCenters":[],"links":[{"id":18806,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.2980/15-2-2882"},{"id":203783,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"15","issue":"2","noUsgsAuthors":false,"publicationDate":"2015-12-03","publicationStatus":"PW","scienceBaseUri":"4f4e4b20e4b07f02db6ab8e2","contributors":{"authors":[{"text":"Middleton, B. 0000-0002-1220-2326","orcid":"https://orcid.org/0000-0002-1220-2326","contributorId":29939,"corporation":false,"usgs":true,"family":"Middleton","given":"B.","affiliations":[{"id":17705,"text":"Wetland and Aquatic Research Center","active":true,"usgs":true}],"preferred":false,"id":345503,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wu, X.B.","contributorId":50640,"corporation":false,"usgs":true,"family":"Wu","given":"X.B.","email":"","affiliations":[],"preferred":false,"id":345504,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70000341,"text":"70000341 - 2008 - Trace-element budgets in the Ohio/Sunbury shales of Kentucky: Constraints on ocean circulation and primary productivity in the Devonian-Mississippian Appalachian Basin","interactions":[],"lastModifiedDate":"2012-03-08T17:16:34","indexId":"70000341","displayToPublicDate":"2010-09-28T23:09:22","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2996,"text":"Palaeogeography, Palaeoclimatology, Palaeoecology","printIssn":"0031-0182","active":true,"publicationSubtype":{"id":10}},"title":"Trace-element budgets in the Ohio/Sunbury shales of Kentucky: Constraints on ocean circulation and primary productivity in the Devonian-Mississippian Appalachian Basin","docAbstract":"The hydrography of the Appalachian Basin in late Devonian-early Mississippian time is modeled based on the geochemistry of black shales and constrained by others' paleogeographic reconstructions. The model supports a robust exchange of basin bottom water with the open ocean, with residence times of less than forty years during deposition of the Cleveland Shale Member of the Ohio Shale. This is counter to previous interpretations of these carbon-rich units having accumulated under a stratified and stagnant water column, i.e., with a strongly restricted bottom bottom-water circulation. A robust circulation of bottom waters is further consistent with the palaeoclimatology, whereby eastern trade-winds drove upwelling and arid conditions limited terrestrial inputs of siliciclastic sediment, fresh waters, and riverine nutrients. The model suggests that primary productivity was high (~ 2??g C m- 2 d- 1), although no higher than in select locations in the ocean today. The flux of organic carbon settling through the water column and its deposition on the sea floor was similar to fluxes found in modern marine environments. Calculations based on the average accumulation rate of the marine fraction of Ni suggest the flux of organic carbon settling out of the water column was approximately 9% of primary productivity, versus an accumulation rate (burial) of organic carbon of 0.5% of primary productivity. Trace-element ratios of V:Mo and Cr:Mo in the marine sediment fraction indicate that bottom waters shifted from predominantly anoxic (sulfate reducing) during deposition of the Huron Shale Member of the Ohio Shale to predominantly suboxic (nitrate reducing) during deposition of the Cleveland Shale Member and the Sunbury Shale, but with anoxic conditions occurring intermittently throughout this period. ?? 2008 Elsevier B.V.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Palaeogeography, Palaeoclimatology, Palaeoecology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/j.palaeo.2008.04.012","issn":"00310182","usgsCitation":"Perkins, R., Piper, D., and Mason, C., 2008, Trace-element budgets in the Ohio/Sunbury shales of Kentucky: Constraints on ocean circulation and primary productivity in the Devonian-Mississippian Appalachian Basin: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 265, no. 1-2, p. 14-29, https://doi.org/10.1016/j.palaeo.2008.04.012.","startPage":"14","endPage":"29","costCenters":[],"links":[{"id":18804,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.palaeo.2008.04.012"},{"id":203629,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"265","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a4ee4b07f02db627b87","contributors":{"authors":[{"text":"Perkins, R.B.","contributorId":49501,"corporation":false,"usgs":true,"family":"Perkins","given":"R.B.","email":"","affiliations":[],"preferred":false,"id":345492,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Piper, D.Z.","contributorId":34154,"corporation":false,"usgs":false,"family":"Piper","given":"D.Z.","email":"","affiliations":[],"preferred":false,"id":345491,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Mason, C.E.","contributorId":30337,"corporation":false,"usgs":true,"family":"Mason","given":"C.E.","email":"","affiliations":[],"preferred":false,"id":345490,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70000324,"text":"70000324 - 2008 - The wister mud pot lineament: Southeastward extension or abandoned strand of the San Andreas fault?","interactions":[],"lastModifiedDate":"2012-03-08T17:16:35","indexId":"70000324","displayToPublicDate":"2010-09-28T23:09:22","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1135,"text":"Bulletin of the Seismological Society of America","onlineIssn":"1943-3573","printIssn":"0037-1106","active":true,"publicationSubtype":{"id":10}},"title":"The wister mud pot lineament: Southeastward extension or abandoned strand of the San Andreas fault?","docAbstract":"We present the results of a survey of mud pots in the Wister Unit of the Imperial Wildlife Area. Thirty-three mud pots, pot clusters, or related geothermal vents (hundreds of pots in all) were identified, and most were found to cluster along a northwest-trending line that is more or less coincident with the postulated Sand Hills fault. An extrapolation of the trace of the San Andreas fault southeastward from its accepted terminus north of Bombay Beach very nearly coincides with the mud pot lineament and may represent a surface manifestation of the San Andreas fault southeast of the Salton Sea. Additionally, a recent survey of vents near Mullet Island in the Salton Sea revealed eight areas along a northwest-striking line where gas was bubbling up through the water and in two cases hot mud and water were being violently ejected.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Bulletin of the Seismological Society of America","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1785/0120070252","issn":"00371106","usgsCitation":"Lynch, D., and Hudnut, K., 2008, The wister mud pot lineament: Southeastward extension or abandoned strand of the San Andreas fault?: Bulletin of the Seismological Society of America, v. 98, no. 4, p. 1720-1729, https://doi.org/10.1785/0120070252.","startPage":"1720","endPage":"1729","costCenters":[],"links":[{"id":476512,"rank":10000,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"https://resolver.caltech.edu/CaltechAUTHORS:LYNbssa08","text":"External Repository"},{"id":18791,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1785/0120070252"},{"id":203474,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"98","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a0ce4b07f02db5fc98c","contributors":{"authors":[{"text":"Lynch, D.K.","contributorId":33436,"corporation":false,"usgs":true,"family":"Lynch","given":"D.K.","email":"","affiliations":[],"preferred":false,"id":345444,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hudnut, K.W.","contributorId":25179,"corporation":false,"usgs":true,"family":"Hudnut","given":"K.W.","email":"","affiliations":[],"preferred":false,"id":345443,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ]}