Late Middle Pleistocene deposits at Norton Farm on the West Sussex coastal plain,southern England     

Martin R. Bates  C. Richard Bates  Philip L. Gibbard  Richard I. Macphail  Frederick J. Owen  Simon A. Parfitt  Richard C. Preece  Mark B. Roberts  J. Eric Robinson  John E. Whittaker  Keith N. Wilkinson 《第四纪科学杂志》2000,15(1):61-89

The coastal plain of West Sussex, southern England, is internationally important because of the sequence of discrete high‐sea‐level events preserved at various elevations across it. New evidence is presented from a site at Norton Farm, near Chichester, on the Lower Coastal Plain, where Pleistocene marine sands, fining upwards into silts, occur between 5.3 m and 9.1 m OD. The sequence reflects a regressive tendency at the transition from an interglacial to a cold stage. The marine sands have yielded foraminifera, ostracods and molluscs that indicate a declining marine influence through the sequence, culminating in a tidal mudflat, strongly weathered in places. Cool‐climate foraminifera (including Elphidium clavatum, Cassidulina reniformis and Elphidium albiumbilicatum) and ostracods have been recovered from the marine sands. Some species with an apparent preference for warmer water conditions, however, are also present. Freshwater taxa washed into the terminal marine sediments include some cold climate indicators, such as Pisidium stewarti and P. obtusale lapponicum. Additional evidence for cool climatic conditions during the deposition of the upper part of the marine sequence is provided by the lack of tree taxa in the pollen record and by features of the micromorphology. The marine sediments probably began accumulating during OIS 7, a conclusion based on their elevation, on amino acid ratios from shells, but especially on vertebrate evidence, particularly the presence of a small form of horse, together with a large, distinctive, form of northern vole (Microtus oeconomus). The occurrence of cool climate indicators in these marine sediments may demonstrate a lag between the climatic deterioration and the expected glacio‐eustatic fall in relative sea‐level. This evidence appears to support the conclusions drawn from the study of coral terraces in Barbados. Such a scenario would provide the conditions necessary for the emplacement of the large erratic boulders reported from the Lower Coastal Plain of West Sussex. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

Frederick C. Leonard: A history and personal recollections     

Frederick D. Leonard 《Meteoritics & planetary science》2018,53(3):359-374

As a child Frederick C. Leonard displayed such a precocious aptitude for astronomy that he became known as “Chicago's Boy Astronomer.” But within a decade after receiving his Ph.D., his interests had turned to meteorites. He persuaded Harvey Nininger to help him found the Society for Research on Meteorites, later renamed The Meteoritical Society, in 1933—a time when the study of meteorites was not considered a worthy pursuit of serious scientists. He nurtured the Society and held it together through the Great Depression, World War II, a destructive feud, and a significant personal and family crisis. He obtained legitimacy and affiliation for the Society with mainstream scientific organizations. He was its first President, and he was Editor of its publications from the Society's founding until a year before his death in 1960. Through it all he was a persistent advocate for the importance of the study of meteorites and the legitimacy of meteoritics as a valuable field of science.  相似文献   

Accounting for correlation among environmental covariates improves delineation of extrapolation suitability index for agronomic technological packages     

Francis Kamau Muthoni  Frederick Baijukya  Mateete Bekunda  Haroon Sseguya  Anthony Kimaro  Tunrayo Alabi 《国际地球制图》2019,34(4):368-390

This paper generates an extrapolation suitability index (ESI) to guide scaling-out of improved maize varieties and inorganic fertilizers. The best-bet technology packages were selected based on yield gap data from trial sites in Tanzania. A modified extrapolation detection algorithm was used to generate maps on two types of dissimilarities between environmental conditions at the reference sites and the outlying projection domain. The two dissimilarity maps were intersected to generate ESI. Accounting for correlation structure among covariates improved estimate of risk of extrapolating technologies. The covariate that highly limited the suitability of specific technology package in each pixel was identified. The impact based spatial targeting index (IBSTI) identified zones that should be prioritized to maximize the potential impacts of scaling-out technology packages. The proposed indices will guide extension agencies in targeting technology packages to suitable environments with high potential impact to increase probability of adoption and reduce risk of failure.  相似文献   

Feeding habits of red drum (Sciaenops ocellatus) in Galveston Bay, Texas: Seasonal diet variation and predator-prey size relationships     

Frederick S. Scharf  Kurtis K. Schlicht 《Estuaries and Coasts》2000,23(1):128-139

Feeding habits, seasonal diet variation, and predator size-prey size relationships of red drum (Sciaenops ocellatus) were investigated in Galveston Bay, Texas through stomach contents analysis. A total of 598 red drum ranging from 291–763 mm total length were collected and their stomach contents analyzed during fall 1997 and spring 1998. The diet of red drum showed significant seasonal patterns, and was dominated by white shrimp (Penaeus setiferus) during fall and gulf menhaden (Brevoortia patronus) during spring. Blue crab (Callinectes sapidus) was an important component of red drum diets during both seasons. Significant differences existed between prey types consumed during fall and spring as red drum diet reflected seasonal variation in prey availability. Predictive regression equations were generated to estimate original carapace width of blue crabs from several measurements taken from carapace fragments recovered in red drum stomachs. Regressions were highly significant (r²>0.97) and increased the number of blue crabs with size information nearly three fold. Predator size-prey size relationships were determined for red drum feeding on white shrimp, gulf menhaden, and blue crab. Although regression slopes were statistically significant, prey sizes increased only slightly with increasing red drum size. Comparisons of prey sizes consumed by red drum with sizes occurring in the field indicate that red drum feed in nearshore shallow water habitats, which serve as nursery areas for many juvenile fishes and crustaceans. Our findings demonstrate that red drum feed on several prey species of commercial and recreational value and may have important effects on estuarine community structure.  相似文献   

Characterizing a Faulted Aquifer by Field Testing and Numerical Simulation     

Diana M. Allenaan  Frederick A. Michel 《Ground water》1999,37(5):718-728

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Integrating Borehole Logs and Aquifer Tests in Aquifer Characterization   总被引：4，自引：0，他引：4  

Frederick L. Paillet  Ronald S. Reese 《Ground water》2000,38(5):713-725

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Eclipses of natural planetary satellites     

C. Frederick Peters 《Celestial Mechanics and Dynamical Astronomy》1975,12(1):99-110

A general method is given for predicting eclipse events for natural planetary satellites suitable for use on a large scale digital computer. The precision is sufficient to process photometric eclipse observations to improve natural satellite ephemerides. Expected accuracy improvement for Saturn's satellites should be an order of magnitude or better. Predicted eclipse times of satellites by Saturn and the Rings are given for the next decade.Presented at IAU Colloquium No. 28, Ithaca, New York, August, 1974.  相似文献   

Dayglow emissions of the O₂ Herzberg bands and the Rayleigh backscattered spectrum of the earth     

J.E. Frederick  R.B. Abrams 《Planetary and Space Science》1982,30(6):575-580

Numerous fluorescent emissions from the Herzberg bands of molecular oxygen lie in the spectral region 242–300 nm. This coincides with the wavelength range used by orbiting spectrometers which observe the Rayleigh backscattered spectrum of the earth for the purpose of monitoring the vertical distribution of stratospheric ozone. Model calculations indicate that Herzberg band emissions in the dayglow could provide significant contamination of the ozone measurements if the quenching rate of O₂(A³Σ) is sufficiently small. This is especially true near 255 nm, where the most intense fluorescent emissions relative to the Rayleigh scattered signal are located and where past satellite measurements show a persistent excess radiance above that expected for a pure ozone absorbing and molecular scattering atmosphere. However, very small quenching rates are adequate to reduce the dayglow emission to negligible levels. Available laboratory data have not definitely established the quenching on the rate of O₂(A³Σ) as a function of vibrational level, and such information is required before the Herzberg band contributions can be evaluated with confidence.  相似文献   

Nuclear war and the oceans     

Sir Frederick Warner 《Marine pollution bulletin》1984,15(8):275-276

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APPLIED GEOGRAPHIC RESEARCH FOR STATE AND LOCAL GOVERNMENT: PROBLEMS AND PROSPECTS     

Frederick P. Stutz 《The Professional geographer》1980,32(4):393-399

Experience with five funded and three unfunded state and local-government research projects involving transportation, land use, and community planning problems reveal that state and local government agencies are usually understaffed and cannot divert resources from immediate needs. A major need is for data and analysis to satisfy short-term responsibilities. In-house staff and consultant companies can best fill this need. Information and analysis for the intermediate and long run can best be developed by the universities because of better-quality research at low costs. Such applied research opportunities at the local and state levels should be sought by geographers. Research of this kind is becoming more accepted vis-á-vis the goals and reward system of the university community.  相似文献