Erratum     

Amy J. G. Jurewicz  E. Bruce Watson 《Contributions to Mineralogy and Petrology》1989,102(2):255-255

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The role of orbit determination in satellite altimeter data analysis     

Bruce C. Douglas  Clyde C. Goad 《Boundary-Layer Meteorology》1978,13(1-4):245-251

The satellite-borne radar altimeters on GEOS 3 and SEASAT produce high-precision measurement of distance from the satellite to the ocean surface. However, the precision of the GEOS 3 altimeter (~50 cm) and especially the forthcoming SEASAT (~10 cm) instrument far exceeds our ability to determine the position of either satellite using conventional electronic or laser-tracking methods. Thus special techniques are required to prevent the uncertainty of the satellite position from degrading the value of the altimeter data. The altimeter data themselves provide a solution to this problem. Using the condition that intersections of passes of altimeter data must measure the same time-invariant part of the sea-surface height, the root-mean-square error of 292 intersections of 47 passes of GEOS 3 altimeter data from the Atlantic Ocean was reduced from 17 m to 44 cm. Simulations of the SEASAT problem also show that altimeter data can aid in determining the satellite orbit, and have their greatest value when radar or laser tracking is sparse.  相似文献   

Amerinds and their paleoenvironments in Northeastern North America : W. S. Newman and B. Salwen, Editors. New York Academy of Sciences, New York, 1977, $35.00     

Bruce J. Bourque 《Quaternary Research》1978,9(3)

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Two-liquid partition coefficients: Experimental data and geochemical implications   总被引：12，自引：0，他引：12  

E. Bruce Watson 《Contributions to Mineralogy and Petrology》1976,56(1):119-134

Partition coefficients for Cs, Ba, Sr, Ca, Mg, La, Sm, Lu, Mn, Ti, Cr, Ta, Zr, and P between immiscible basic and acidic liquids in the system K₂O-Al₂O₃-FeO-SiO₂ were experimentally determined at 1,180 °C and 1 atm. Phosphorus is most strongly enriched in the basic melt (by a factor of 10), followed by rare earth elements, Ta, Ca, Cr, Ti, Mn, Zr, Mg, Sr, and Ba (enriched by a factor of 1.5). Of the elements studied, only Cs is enriched in the acidic melt. The two-liquid partition coefficients of Zr, Ta, Sm, and Mn are constant for concentrations ranging from <0.1% to as high as 1 wt.-%, suggesting that Henry's law is applicable in silicate melts (at least for these elements) to concentrations well above typical trace element levels in rocks. The strong relative preference of many elements for the basic melt implies that the structural characteristics of basic melts more readily permit stable coordination of cations by oxygen. Partitioning of elements between crystal and liquid in a magma must therefore be influenced by the composition (and consequent structure) of the liquid.Application of the two-liquid partition coefficients to possible occurrences of liquid immiscibility in magmas reveals that typical basalt-rhyolite associations are probably not generated by two-liquid phase separation. However, liquid immiscibility cannot be discounted as a possible origin for lamprophyric rocks containing felsic segregations.  相似文献   

Glass inclusions as samples of early magmatic liquid: determinative method and application to a south atlantic basalt   总被引：1，自引：0，他引：1  

E.Bruce Watson 《Journal of Volcanology and Geothermal Research》1976,1(1):73-84

Silicate melt inclusions in phenocrysts are not directly representative of trapped magmatic liquid because chemical interaction between inclusions and host crystals usually occurs after melt entrapment. However, if more than one phenocryst type in a suite of rocks contains melt inclusions, the original trapped-liquid composition can be accurately fixed by the intersection of host-mineral fractionation lines in a triangular oxide plot of inclusion analyses. When plotted on a CaO—MgO—Al₂O₃ triangular diagram, analyses of inclusions in plagioclase, olivine, and clinopyroxene from a basalt dredged off Bouvet Island fall along crystal fractionation lines that intersect at a single point. This point represents an initial trapped liquid composition rich in CaO and MgO, and low in TiO₂ and total alkalies. The composition is transitional between tholeiite and basaltic komatiite, and may be indicative of extensive melting of clinopyroxene in the mantle.  相似文献   

An Integrated Approach to Delineating Contaminated Ground Water     

William J. Berk  Bruce S. Yare 《Ground water》1977,15(2):138-145

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Partitioning of manganese between forsterite and silicate liquid   总被引：1，自引：0，他引：1  

E. Bruce Watson 《Geochimica et cosmochimica acta》1977,41(9):1363-1374

Partition coefficients for Mn between forsterite and liquid in the system MgO-CaO-Na₂O-Al₂O₃-SiO₂ (+ about 0.2% Mn) were measured by electron microprobe for a variety of melt compositions over the temperature range 1250–1450°C at one atm pressure. The forsterite-liquid partition coefficient of Mn (mole ratio, MnO in Fo/MnO in liquid, designated D_mn^fo?Liq) depends on liquid composition as well as temperature: at 1350°C, D_Mn^Fo?Liqranges from 0.60 (basic melt, SiO₂ = 47wt%) to 1.24 (acidic melt, SiO₂ = 65wt%). At lower temperatures, the partition coefficient is more strongly dependent on melt composition.The effects of melt composition and temperature on D_Mn^fo?Liq can be separately evaluated by use of the Si:O atomic ratio of the melts. A plot of D_mn^Fo?Liq measured at various temperatures vs melt Si:O for numerous liquid compositions reveals discrete, constant-temperature curves that are not well defined by plotting D_Mn^Fo?Liq against other melt composition parameters such as melt basicity or MgO content. For constant Si:O in the melt, In D_Mn^Fo?Liq vs reciprocal absolute temperature is linear; however, the slope of the plot becomes more positive for higher values of Si:O, indicating a higher energy state for Mn²⁺ ions in acidic melts than in basic melts.Comparison of Mn partitioning data for the iron-free system used in this study with data of other workers on iron-bearing compositions suggests that the effect of iron on Mn partitioning between olivine and melt is small over the range of basalt liquidus temperatures.  相似文献   

Methods for estimating Curie temperatures of titanomaghemites from experimentalJ_s-T data     

Bruce M. Moskowitz 《Earth and Planetary Science Letters》1981,53(1):84-88

Methods for determining the Curie temperature (T_c) of titanomaghemites from experimental saturation magnetization-temperature (J_s-T) data are reviewed.J_s-T curves for many submarine basalts and synthetic titanomaghemites are irreversible and determining Curie temperatures from these curves is not a straightforward procedure. Subsequently, differences of sometimes over 100°C in the values ofT_c may result just from the method of calculation. Two methods for determiningT_c will be discussed: (1) the graphical method, and (2) the extrapolation method. The graphical method is the most common method employed for determining Curie temperatures of submarine basalts and synthetic titanomaghemites. The extrapolation method based on the quantum mechanical and thermodynamic aspects of the temperature variation of saturation magnetization nearT_c, although not new to solid state physics, has not been used for estimating Curie temperatures of submarine basalts. The extrapolation method is more objective than the graphical method and uses the actual magnetization data in estimatingT_c.  相似文献   

$\text{Sr}\text{Ca}$ and $\text{Mg}\text{Ca}$ ratios in polygenetic carbonate allochems from a Michigan marl lake     

Thomas N Treese  Robert M Owen  Bruce H Wilkinson 《Geochimica et cosmochimica acta》1981,45(3):439-445

Rapid accumulation of CaCO₃ is occurring in Littlefield Lake, a marl lake located in central Michigan. The sediment, which is 95% CaCO₃, primarily consists of eight different genetic groups of carbonate allochems. These include calcite muds, sands, algal oncoids and Chara encrustations, as well as the dominant aragonitic gastropods Valvota tricarinota. Gyraulus deflectus and Amnicola integra. and the dominant aragonitic pelecypod Sphaerium partumeium. Samples of each of these groups were analyzed for Ca, Sr and Mg. Molar $\text{Mg}\text{Ca}$ ratios are primarily controlled by allochem mineralogy, with calcitic forms having $\text{Mg}\text{Ca}$ ratios 5–10 times larger than aragonitic (shelled) forms. The $\text{Sr}\text{Ca}$ ratios are primarily controlled by biochemical fractionation, and are significantly lower than $\text{Sr}\text{Ca}$ ratios of inorganically precipitated aragonite from other settings. Partition coefficients were determined for both Sr and Mg for each carbonate allochem group and, based on comparisons with results reported by other workers, the partition coefficients determined here are generally considered ‘typical’ or representative values for biogeneous freshwater carbonates. An analysis of variance of the data indicates that most genera and species of carbonate-secreting organisms in marl lakes have highly characteristic $\text{Sr}\text{Ca}$ and $\text{Mg}\text{Ca}$ ratios. These ratios can potentially serve as geochemical tracers in future investigations of lacustrine carbonate diagenesis. Both Sr and Mg are influenced by grain size and/or surface area, probably due to the presence of these elements in non-lattice-held (exchangeable) positions.  相似文献   

Stratigraphy of late Quaternary estuarine deposits and amino acid stereochemistry of oyster shells beneath San Francisco Bay,California     

Brian F. Atwater  Bruce E. Ross  John F. Wehmiller 《Quaternary Research》1981,16(2):181-200

The sequence of Quaternary deposits beneath the floor of San Francisco Bay includes four to seven noncontemporaneous estuarine units intercalated with alluvium and dune sand. Units L (0–10,000 B.P.), M (>40,000 B.P., probably ca. 80,000–140,000 B.P.), and N (older than unit M) are distinctly superposed. The dominant molluscan fossil in each of these three units is Ostrea lurida Carpenter, the native oyster along much of the pacific Coast of North America. Despite a lamellar structure that suggests vulnerability to contamination, O. lurida shells generally yield amino acid enantiomeric ratios that are analytically reproducible and stratigraphically consistent. The kinetics of racemization in O. lurida conceivably resembles that of Protothaca and Saxidomus, other bivalves whose kinetics of racemization are relatively well understood. Assuming such a resemblance, enantiomeric ratios in O. lurida imply that (1) unit M is the same approximate age as estuarine terrace deposits bordering San Pablo Bay and Carquinez Strait, providing that the terrace deposits have been at diagenetic temperatures 1°-2°C warmer than unit M; and (2) the age of unit N is about four times greater than that of unit M, providing that both units have been at the same approximate diagenetic temperature.  相似文献