Book reviews     

Charles W. Howe  A. Hecht 《Climatic change》1995,31(1):119-126

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SPECTROPHOTOMETRIC DETERMINATION OF FERROUS IRON IN EIGHTEEN UNITED STATES GEOCHEMICAL REFERENCE STANDARDS     

Charles B. Bruce  Jr.  Nathan W. Bower 《Geostandards and Geoanalytical Research》1987,11(1):41-42

Iron (II) oxide in 50 mg samples of silicate rocks, deposits, and soils is measured after digestion with HF and HCl in the presence of ICl. The iodine produced is measured spectrophotometrically. Results are presented for the eighteen available USGS geochemical reference standards including the GXR series.  相似文献   

Age and significance of fossil white spruce (Picea glauca), Tunica Hills, Louisiana-Mississippi     

Charles R. Givens  Florence Montgomery Givens 《Quaternary Research》1987,27(3)

Radiocarbon dates indicate a Farmdalian through Woodfordian age for fossil white spruce (Picea glauca) in the Tunica Hills, a greater time span than previously documented. These dates, furthermore, require revision of the ages of fluvial terrace deposits in the region. Spruce-bearing Terrace 1 sediments, previously regarded as late Woodfordian to Holocene age, are of Farmdalian to late Holocene age. Terrace 2 sediments, previously assigned a Sangamonian or Farmdalian age, are of probable Altonian age. Plant fossils in Terrace 1 sediments represent two climatically and temporally distinct assemblages: a cool-temperate, Farmdalian-Woodfordian assemblage dominated by white spruce but including deciduous hardwoods suggestive of an oak-hickory association; and a warm-temperate Holocene assemblage composed of southern hardwoods and nonarboreal species representative of the modern flora of the Tunica Hills. Locally, fossils of white spruce have been reworked into younger Terrace 1 sediments containing the warm-temperate plant assemblage. The transition from the cool-temperate flora to the modern warm-temperate flora in the Tunica Hills probably occurred around 12,000 yr B.P.  相似文献   

Storage and Retrieval of Ground-Water Data at the U.S. Geological Survey     

Maria W. Mercer  Charles O. Morgan 《Ground water》1982,20(5):543-551

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The geodetic requirements for commercial data base management systems     

Charles R. Schwarz 《Journal of Geodesy》1982,56(2):165-176

There are many data base management systems now available as commercially marketed software packages. Although most of these packages were initially aimed at bussiness or administrative data processing applications, they may frequently also be the right tool for a scientific data processing task. This becomes more apparent as we notice that scientific computer programmers are spending more and more time on data management requirements rather than the coding of mathematical algorithms. In a scientific environment, a generalized data base management package is best viewed as a tool for programmers, rather than as a tool for direct, independent use by end users or by agency management. To the end user, the most attractive feature of a commerical DBMS is usually the interactive retrieval and update language. To the programmer, the most attractive feature is more likely to be the strong support for various types of keyed access. All of the manipulations necessary to build and maintain indices and other tables can be treated as procedural abstractions. Coupled with a procedural language, a DBMS offers the programmer a higher level (in the sense of more abstract) language. The most important geodetic requirement on a commercial DBMS is therefore that the package contain a strong Data Manipulation Language, with strong support for the algorithmic language used for scientific processing. Presented at International Symposium on Management of Geodetic Data, Copenhagen, August 24–26, 1981.  相似文献   

A comparison of dispersal strategies in two genera of brachyuran crab in a secondary estuary     

Rose Lambert  Charles E. Epifanio 《Estuaries and Coasts》1982,5(3):182-188

Seasonal occurrence and vertical distribution of larvae of two genera of brachyuran crab were studied in a secondary estuary flowing into Delaware Bay. Spawning in the xanthid crabRhithropanopeus harrisii occurred earlier with peak abundance of larvae in June and with a distinct decline in abundance in August. In contrast,Uca spp. larvae reached peak abundance in August. All zoeal stages ofR. harrisii were collected in the river suggesting that larvae of this species are retained in secondary estuaries near areas of prime adult habitat. Only zoea stage I larvae and megalopa ofUca spp. were collected in the river indicating that larvae of these speies may be flushed into the Delaware Bay and may not return to secondary estuaries near areas suitable for adult habitat until the megalopa stage is reached. It is not clear if this dispersal pattern is an active or passive process. *** DIRECT SUPPORT *** A01BY019 00004  相似文献   

Annual cycle of kepone® residue and lipid content of the estuarine clam,Rangia cuneata     

Charles A. Lunsford  Charles R. Blem 《Estuaries and Coasts》1982,5(2):121-130

Factors affecting Kepone uptake and lipid content of the clam,Rangia cuneata, were tested over a 12 month study. Clams obtained from the Rappahannock and James Rivers were held in submersible liver boxes at two sites in the James River estuary and were sampled monthly from September 1978 through August 1979. Clams held in the freshwater zone near the source of Kepone contamination (Hopewell, Virginia) generally had higher Kepone and lipid content than those held downstream in the oligohaline zone. Significant differences in Kepone content between test sites and months are largely, but not entirely, a function of ambient water temperature, dissolved oxygen, amount of lipid in the clam, turbidity, Kepone content of the water column and duration of exposure. Lipid content of clams varied significantly between test sites, river of origin and months and is significantly related to salinity, ambient water temperature, pH and duration of exposure. Kepone content was more closely correlated with total lipid stores of clams than any other real variable. This association may be due to lipid reserves acting as a storage site for Kepone, but may also be interpreted as the result of selection against clams lacking lipid stores that might act as reservoirs for Kepone thus protecting more delicate tissues.  相似文献   

Statistical theory and methodology of trace analysis: C. Liteanu and I. Rica,Wiley, 1980, 446 p., $99.95 (US), $127.95 (CDN)     

Charles H. Goldsmith 《Geochimica et cosmochimica acta》1982,46(6):1143-1144

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Mineral equilibria in the six-component seawater system,Na-K-Mg-Ca-SO4-Cl-H2O at 25°C. II: Compositions of the saturated solutions     

Charles E. Harvie  Hans P. Eugster  John H. Weare 《Geochimica et cosmochimica acta》1982,46(9):1603-1618

Using the solubility model developed by Harvie and Weare (1980), the stable mineral-solution assemblages for the six-component system Na-K-Mg-Ca-SO₄-Cl-H₂O and its constituent 5-, 4- and 3-component systems at 25°C have been defined. Invariant point maps have been constructed showing the connections by univariant lines. The solubility volumes for all 20 minerals considered are also illustrated. Of the 37 invariant points, only 3 have solutions which are Ca-rich; the remaining 34 can be plotted in the reciprocal system Na-K-Mg-SO₄-Cl, which is similar to the seawater system, except that the restriction of halite saturation has been removed. Application of these results and implications for the evolution of major brine types are briefly discussed.  相似文献   

Analysis of palaeomagnetic time series — Techniques and applications     

Charles E. Barton 《Surveys in Geophysics》1983,5(4):335-368

This review is intended to provide an introduction for the nonspecialist to concepts and techniques which are useful for analysing palaeomagnetic time series. Emphasis is placed on analysis in the frequency domain, particularly the periodogram and maximum entropy methods. The review consists of two parts dealing with techniques and applications respectively.  相似文献