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1.
C.S. Botzler J. Snigula R. Bender N. Drory G. Feulner G.J. Hill U. Hopp C. Maraston C. Mendes de Oliveira 《Astrophysics and Space Science》2003,284(2):393-396
The Munich Near-IR Cluster Survey (MUNICS) is a wide-area, medium-deep, photometric survey selected in the K' band. The project's
main scientific aims are the identification of galaxy clusters up to redshifts of unity and the selection of a large sample
of field early-type galaxies up to z < 1.5 for evolutionary studies. We created a Large Scale Structure catalog, using a new structure finding technique specialized
for photometric datasets, that we developed on the basis of a friends-of-friends algorithm. We tested the plausibility of
the resulting galaxy group and cluster catalog with the help of Color-Magnitude Diagrams (CMD), as well as a likelihood- and
Voronoi-approach.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
2.
In this paper we view the different practices of archaeology, anthropology, environmental reconstruction and geomorphology through the lens of fieldwork on the clitter fields and Bronze Age settlement patterns on Leskernick Hill, Bodmin Moor, southwest Britain. The moor forms one of the best preserved fossil prehistoric landscapes of Europe and has undergone repeated periglacial episodes during the Quaternary. We show that the characterisation of patterned ground by archaeologists and anthropologists can be very different from that generated by geomorphology, particularly with respect to the spatial scales at which culture/nature questions are posed. We argue that the research project at Leskernick is a good example of how multi-disciplinary work is often more fruitful than mono-disciplinary and provides an example of how conversations across the divides of disciplinary practice can be held. 相似文献
3.
In the Alexander von Humboldt National Park in eastern Cuba many endemic animals and plants are found in various different natural habitats, which are considered to be the most important ones for in-situ conservation in the entire Insular Caribbean. In some areas of the National Park agriculture is practised. Thus, the objective of this study was to document and analyse the different land use activities and their consequences for local resource management and conservation of biodiversity in two village areas. A particular question was: what has changed since the foundation of the National Park in 1996? As time series data for land use and aerial photographs were not available for this part of Cuba, a qualitative evaluation was carried out. For this, six different land use units were mapped in 2001 and additional information gathered for areas with special interest related to sustainable land use and resource conservation. Although most parts of the study area are influenced to various degrees by human impact, the different types of land use seem presently not to have a crucial or detrimental impact on the land resources of the Alexander von Humboldt National Park. However, exploitation of the natural resources in certain areas could be improved with different management options to reach sustainability as well as to meet the conservation objectives of the National Park. This includes reduced or abandoned agricultural use of steep slopes to reduce erosion risk as well as a facilitated regeneration of natural vegetation in many parts of the study area to be able to conserve the high valuable biodiversity of the Park. Environmental education seems to have played an important and successful role since the foundation of the Park in 1996. Since then, cropping on steep slopes as well as illegal logging and poaching could be reduced. 相似文献
4.
Todd P. Trooien Alan R. Bender John H. Bischoff 《Ground Water Monitoring & Remediation》1986,6(2):99-105
The union of a piezoresistive pressure transducer and a porous ceramic cup was termed "transiometer." The transiometer was constructed from economical and readily available materials. It could be used to measure soil water potentials in both saturated and unsaturated conditions, and was well suited to continuous monitoring with data acquisition equipment.
Transiometer testing was conducted at two sites, one of moderate permeability and the other of slow permeability. The slowly permeable site was instrumented with four replications of the following: (1) transiometers installed at four depths, (2) a transi-ometerwithout the ceramic cup, (3) apiezometer, and (4) access tubes for monitoring soil moisture with a neutron probe. The moderately permeable site was instrumented with a transiometer, two piezometers, and an access tube for monitoring with a neutron probe.
In saturated conditions the transiometer had a faster response time after installation than the piezometer. Faster response makes the transiometer more desirable for use in slowly permeable soils, especially when monitoring dynamic soil water.
Calculated random error of the transiometer measuring system, including a digital voltmeter and a scanner, was typically 0.09 feet (2.8cm), with a maximum calculated to be 0.38 feet (11.5cm). The two most significant components were imprecision of the scanner card and calibration shift. The transiometer was sensitive to atmospheric pressure fluctuations, with sensitivity to atmospheric pressure change increasing with installation depth. 相似文献
Transiometer testing was conducted at two sites, one of moderate permeability and the other of slow permeability. The slowly permeable site was instrumented with four replications of the following: (1) transiometers installed at four depths, (2) a transi-ometerwithout the ceramic cup, (3) apiezometer, and (4) access tubes for monitoring soil moisture with a neutron probe. The moderately permeable site was instrumented with a transiometer, two piezometers, and an access tube for monitoring with a neutron probe.
In saturated conditions the transiometer had a faster response time after installation than the piezometer. Faster response makes the transiometer more desirable for use in slowly permeable soils, especially when monitoring dynamic soil water.
Calculated random error of the transiometer measuring system, including a digital voltmeter and a scanner, was typically 0.09 feet (2.8cm), with a maximum calculated to be 0.38 feet (11.5cm). The two most significant components were imprecision of the scanner card and calibration shift. The transiometer was sensitive to atmospheric pressure fluctuations, with sensitivity to atmospheric pressure change increasing with installation depth. 相似文献
5.
David W. Graham Michael L. Bender Douglas F. Williams Lloyd D. Keigwin 《Geochimica et cosmochimica acta》1982,46(7):1281-1292
The ratio and other parameters have been measured in fossil planktonic foraminifera from the Atlantic and Pacific Ocean basins in order to evaluate the ratio of seawater during the last 75 million years. Results on well-preserved samples indicate that the ratio has increased to its present value by 10–15% during the Cenozoic, and that minima occurred between 55-45 Ma and 10-5 Ma, when the ratio was 15–25% less than at present. The long-term increase may reflect either decreasing deposition of aragonite with a high ratio in shallow seas, or decreasing seafloor spreading rates and consequently decreasing hydrothermal supply of Ca during the Cenozoic. Other geologic evidence suggests that the Eocene minimum (near 50 Ma) may have resulted from increased aragonite sedimentation, while the Late Miocene minimum (between 10-5 Ma) may have been caused by an increased rate of seawater-basalt exchange when seafloor spreading rates increased on the East Pacific Rise near 10 Ma. 相似文献
6.
Kurt Bender Ulrich Chorus Raymond Nybro Robert Sanderson Ingrid Weiss 《Pure and Applied Geophysics》1957,38(1):265-285
Summary UsingCraddock's method of representing the annual temperature variation by a two-term harmonic form fitted to monthly means, the harmonic coefficients of 63 stations in western Europe and around the Mediterranean Sea, as well as the 5-day normals for 24 Mediterranean stations, were computed and tabulated. In addition, some of the harmonic coefficients were charted and isoplethed, showing very distinctly the influence of continentality and topography. These charts, together withCraddock's charts for northern and northwestern Europe, provide fairly complete coverage of Europe and the Mediterranean area.This paper was prepared in the offices of the Technical Support Division of the 2d Weather Wing, United States Air Force, as a matter of routine business. The information contained herein was presented at the 5th Meeting of the Italian Society of Geophysics and Meteorology by Dr.Ingrid Weiss (Genoa: 23–25 April 1957). Since the paper is of general interest to all meteorologists of the Mediterranean area, it is published here with the permission of the originating agency as «Mémoire No. 3 du Centre International de Recherches sur la Météorologie de la Méditerranée (CIRMM)». 相似文献
7.
By He-U dating of corals from elevated Pleistocene reef tracts on Barbados, we have extended back to the Middle Pleistocene the high sea stand chronology previously deduced by Th230-U dating. Six samples from the first major reef tract complex older than the 200,000-yr complex gave ages of 350,000 ± 25,000 yr B.P. Two corals from the crest of Second High Cliff, an unusually large escarpment occurring approximately midway in the terrace sequence, gave concordant ages of 480,000 and 500,000 yr. Unrecrystallized corals from older reefs gave ages ranging back to 650,000 yr.The results date episodes of high sea stands at 350,000 and 500,000 yr B.P. 相似文献
8.
Petrogenesis of basalts from the project FAMOUS area: experimental study from 0 to 15 kbars 总被引:1,自引:0,他引:1
Tholeiitic basalt glasses from the FAMOUS area of the Mid-Atlantic Ridge are among the most primitive basaltic liquids reported from the ocean basins. One of the more primitive of these[Mg/(Mg+Fe2+) = 0.68;Ni= 232ppm;TiO2 = 0.61] glasses (572-1-1) was selected for an experimental investigation. This study found olivine to be the liquidus phase from 1 atm to 10.5 kbar where it is replaced by clinopyroxene. The sequence of appearance of phases at 1 atm pressure is olivine (1268°C), plagioclase (1235°C) and clinopyroxene (1135°C). The sample is multiply saturated at 10.5 kbar with olivine (Fo88), clinopyroxene (Wo32En60Fs9), and orthopyroxene (Wo5En83Fs12). From the 1-atm data we have measured (FeO/MgO) olivine/(FeO*/MgO) liquid (K′D) for olivine-melt pairs equilibrated at 12 temperatures in the range 1268–1205°C.K′D varies from 0.30 at 1205°C to 0.27 at 1268°C. Analysis of high-pressure olivine melt pairs indicates a systematic increase inK′D with pressure.Evaluation of the 1-atm experiments reveals that fractionation of olivine followed by olivine + plagioclase can generate much of the variation in major element chemistry observed in the FAMOUS basalt glasses. However, it cannot account for the entire spectrum of glass compositions — particularly with respect to TiO2 and Na2O. The variations in these components are such as to require different primary liquids.Comparison of clinopyroxene microphenocrysts/xenocrysts found in oceanic tholeiites with experimental clinopyroxenes reveal that the majority of those in the tholeiites may have crystallized from the magma at pressures greater than ~ 10 kbar and are not accidental xenocrysts. Clinopyroxene fractionation at high pressures may be a viable mechanism for fractionating basaltic magmas.The major and minor element mineral/meltK′d's from our experiments have been used to model the source region residual mineralogy for given percentages of partial melting. These data suggest that ~20% partial melting of a lherzolite source containing 0–10% clinopyroxene can generate the major and minor element concentrations in the parental magmas of the Project FAMOUS basalt glasses. 相似文献
9.
Based on phosphorus, iron and manganese analyses in 16 cores (5 dated) from the crest and flanks of the East Pacific Rise and the Bauer Deep we estimate that phosphorus is being deposited about 20 times faster in metalliferous sediments near the rise crest than in adjacent flank deposits, and about 40 times faster on the crest than in the Bauer Deep. Almost all of the phosphorus on the rise crest is contained in poorly crystallized hydrothermal iron oxyhydroxides, supporting Berner's (1973) proposal of phosphate sorption by these phases. The phosphate is probably derived from seawater, but some hydrothermal contribution cannot be excluded at this time. Flux estimates indicate that metalliferous sedimentation could remove 15–40% of the pre-agricultural river input of dissolved phosphate. 相似文献
10.
Christian Kronborg Henry Bender Regnar Bjerre Rud Friborg Hans O. Jacobsen Lars Kristiansen Poul Rasmussen Poul R. Sørensen Gunnar Larsen 《Boreas: An International Journal of Quaternary Research》1990,19(3):273-287
Glaciostratigraphic investigations at one key locality (Haldum), 9 major and about 160 minor localities in East and Central Jutland, Denmark, together with laboratory work, have led to the establishment of a stratigraphy consisting of 10 till units, usually separated by meltwater deposits. The stratigraphy is in some degree supported by thermoluminescence datings. The complete sequence includes one till unit with associated meltwater deposits of Menapian age, three till units with intercalated meltwater deposits of Elsterian age, marine sediments deposited during the Holsteininan, and three till units with intercalated of Elsterian age, marine sediments deposited during the Holsteinian, and three till units with intercalated glaciofluvial sedimants of Saalian age. Eemian deposits are present above this level, and the whole sequence is capped by till and meltwater deposits related to three glacial advances during the Weichselian. 相似文献