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Central Washington University

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Iron Sources And Dissolved-Particulate Interactions In The Seawater Of The Western Equatorial Pacific, Iron Isotope Perspectives, M. Labatut, F. Lacan, C. Pradoux, J. Chmeleff, A. Radic, J. W. Murray, F. Poitrasson, Anne M. Johansen, F. Thil Oct 2014

Iron Sources And Dissolved-Particulate Interactions In The Seawater Of The Western Equatorial Pacific, Iron Isotope Perspectives, M. Labatut, F. Lacan, C. Pradoux, J. Chmeleff, A. Radic, J. W. Murray, F. Poitrasson, Anne M. Johansen, F. Thil

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This work presents iron isotope data in the western equatorial Pacific. Marine aerosols and top core margin sediments display a slightly heavy Fe isotopic composition (δ56Fe) of 0.33 ± 0.11‰ (2SD) and 0.14 ± 0.07‰, respectively. Samples reflecting the influence of Papua New Guinea runoff (Sepik River and Rabaul volcano water) are characterized by crustal values. In seawater, Fe is mainly supplied in the particulate form and is found with a δ56Fe between −0.49 and 0.34 ± 0.07‰. The particulate Fe seems to be brought mainly by runoff and transported across continental shelves and slopes. …

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Land Use Influences The Spatiotemporal Controls On Nitrification And Denitrification In Headwater Streams, Clay P. Arango, J. L. Tank Mar 2008

Land Use Influences The Spatiotemporal Controls On Nitrification And Denitrification In Headwater Streams, Clay P. Arango, J. L. Tank

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N and C cycles in headwater streams are coupled, and land use can modify these cycles by increasing N availability and removing riparian vegetation. To increase our understanding of how land use modifies the controls on N cycling, we quantified rates of 2 microbial N transformations in a total of 18 agricultural and urban streams (with and without riparian buffers) for 3 y to examine how riparian vegetation and land use influence sediment nitrification and denitrification. Nitrification rates were highest in agricultural streams in late spring. Nitrification was not related to streamwater NH4+ concentrations but was positively related …

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Estimation Of Iron Solubility From Observations And A Global Aerosol Model, Chao Luo, N. M. Mahowald, N. Meskhidze, Y. Chen, R. L. Siefert, A. R. Baker, Anne M. Johansen Dec 2005

Estimation Of Iron Solubility From Observations And A Global Aerosol Model, Chao Luo, N. M. Mahowald, N. Meskhidze, Y. Chen, R. L. Siefert, A. R. Baker, Anne M. Johansen

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Mineral aerosol deposition is the dominant source of iron to the open ocean. Soil iron is typically insoluble and understanding the atmospheric processes that convert insoluble iron to the more soluble forms observed over the oceans is crucial. In this paper, we model several proposed processes for the conversion of Fe(III) to Fe(II), and compare with cruise observations. The comparisons show that the model results in similar averaged magnitudes of iron solubility as measured during 8 cruises in 2001–2003. Comparisons show that results of cases including cloud, SO2 and hematite processing are better than the other approaches used using …

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Tertiary Coniferous Woods Of Western North America, George F. Beck Aug 1945

Tertiary Coniferous Woods Of Western North America, George F. Beck

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Almost four decades have elapsed since Platen (1908), the German paleobotanist, published his report upon the fossil woods of the western United States. Since then no over-all treatment of these materials has been attempted. although Platen overlooked the Pacific Northwest with its abundance of Tertiary petrified woods. The purpose of this paper is to bring knowledge of the western coniferous woods of the Tertiary up to date. In this effort the writer recognizes that much of this information has been accumulated incidentally in the study of the Russell Petrified Forest series of central Washington, and that it is not as …

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Nyssa Woods Of The Pacific-Northwest Tertiary, George F. Beck Feb 1945

Nyssa Woods Of The Pacific-Northwest Tertiary, George F. Beck

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The nyssa gums are one of the modern genera of trees most certainly present among the petrified woods and forests of the Pacific Northwest. Almost every collection from the mid-Tertiary of this region contains a few specimens of typical tupelo or sour gum. These are fine-grained woods which to the unaided eye may be mistaken for conifers.

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Ancient Maples Of The Central Washington Region, George F. Beck Nov 1944

Ancient Maples Of The Central Washington Region, George F. Beck

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When I began work on the petrified logs of the general Vantage area some 13 years ago, it became apparent at once that maple-like woods are commonplace in the main (Vantage) raft forest and slightly less abundant in two rooted units of the Yakima Canyon. So widely do these woods range throughout the structural variations found in modern maples that little success has attended the efforts to assign them to nominal species. The extremes can readily be established but few hints exist as to the boundaries between them.

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Two Newly Discovered Conifers, George F. Beck Apr 1944

Two Newly Discovered Conifers, George F. Beck

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Two genera of coniferous wood, apparently not listed among the Tertiary woods of the western states, have been recognized in the Percy Train collections from Rainbow Ridge, northwestern Nevada. These two, Tsuga (hemlock) and Chamaecyparis (cedar) bring up to 14 the genera of coniferous wood more or less certainly identified from the period and area in question.

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Status Of Tertiary Woods Of The Western States Representing The Juglandaceae, George F. Beck Apr 1944

Status Of Tertiary Woods Of The Western States Representing The Juglandaceae, George F. Beck

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For many years there has been uncertainty concerning the generic status of some fossil leaves belonging without question to the walnut family as a whole. A review of the woods of Juglandaceae as they have appeared in Tertiary horizons of the western states has suggested which genera are present, and in what proportions their leaves (or other remains) might be expected to appear.

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Spruce In The Western Miocene, George F. Beck Nov 1936

Spruce In The Western Miocene, George F. Beck

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One of the real surprises in store for us as we began to section specimens of petrified wood from the Vantage and certain other horizons in Central Washington, was the prevalence of a spruce type hardly hinted at in the leaf lists as published for the various sediments of Yakima time (upper miocene?).

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Exotic Ancient Forests Of Washington, George F. Beck Apr 1935

Exotic Ancient Forests Of Washington, George F. Beck

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The greatest fossil forest in the world is located within easy driving distance of the University of Washington campus in the State of Washington, near the Columbia River, east of the city of Ellensburg. Mr. George F. Beck, a member of the faculty of the Ellensburg State Normal School, and a former graduate student of the College of Forestry of the University of Washington, discovered this forest, which is now known as the Ginkgo Forest State Park. Aside from its importance from a scientific point of view, this "petrified forest," which contains a greater variety of species than any other …

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