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51.
Two sections of the Vocontian basin (southeast France) were explored for their radiolarian content. Preservation in calcite impeded their extraction from the Châteauneuf d’Oze section, which is well dated by ammonites. Fortunately, oligospecific assemblages of pyritized radiolaria were yielded by twelve limestone beds of the Méouge section. In general, preservation worsens towards the top of the section. The extracted fauna is dominated by Nassellaria and more particularly by Archaeodictyomitridae, Pseudodictyomitridae and Williriedellidae. It is the first time that some species are reported outside their type area or from Western Tethys. Amongst the published zonations the scheme of Baumgartner et al. (1995a) is found to be the most useful and allows correlation of the studied part of the section with the mid-late Oxfordian to late Kimmeridgian-early Tithonian time interval. 相似文献
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Geotectonics - The Early Oligocene alkalibasalts exposed in the Central Toveireh area located in the southwest of Jandaq city in Isfahan Province (Iran) and northwest of the Central-East Iranian... 相似文献
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Seifollahi Mehran Abbasi Salim Abraham John Norouzi Reza Daneshfaraz Rasoul Lotfollahi-Yaghin Mohammad-Ali Alkan Ahmet 《Geotechnical and Geological Engineering》2022,40(11):5481-5496
Geotechnical and Geological Engineering - The aim of this study is to optimize the geometric dimensions of the Koyna concrete weight dam with and without seismic forces using the grasshopper... 相似文献
55.
Hammad Tariq Janjuhah Ahmed Mohammad Ahmed Salim Abubaker Alansari Deva Prasad Ghosh 《Arabian Journal of Geosciences》2018,11(9):204
The Luconia Province—offshore Sarawak—is a key hydrocarbon province in Malaysia. However, the gas reservoirs in Central Luconia pose unique problems and challenges as they have partially water-filled microporosity that overprint wireline logs. Microporosity in Central Luconia occurs throughout the Miocene carbonates and is a crucial element that influences fluid flow properties and ultimately the recovery of hydrocarbons. Quantification of macroporosity was achieved using petrographic analysis of thin sections and the FESEM images. The point counting technique was used to estimate the amount of macroporosity from the thin section, which was then subtracted from the total porosity to derive microporosity. The qualitative investigation of the Miocene carbonates indicates the presence of three different types of microporosity namely grain-based microporosity, matrix-based microporosity, and cement-based microporosity. Quantification of microporosity showed that the microporosity varies from sample to sample, ranging from 10 to 60% of the total measured porosity. The depositional texture, mineralogy, and microtexture control this microporosity variation including its abundance and type. The microporosity in Central Luconia is diagenetically controlled based on four major diagenetic mechanisms namely (1) mechanical process/endolithic grains/marine diagenesis; (2) leaching/meteoric diagenesis; (3) cementation/shallow diagenesis; and (4) deeper diagenesis environment. 相似文献
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Wahyudi A’an J. Rahmawati Susi Irawan Andri Hadiyanto Hadiyanto Prayudha Bayu Hafizt Muhammad Afdal Afdal Adi Novi S. Rustam Agustin Hernawan Udhi. E. Rahayu Yusmiana P. Iswari Marindah Y. Supriyadi Indarto H. Solihudin Tubagus Ati Restu Nur Afi Kepel Terry L. Kusumaningtyas Mariska A. Daulat August Salim Hadiwijaya L. Sudirman Nasir Suryono Devi D. Kiswara Wawan 《Ocean Science Journal》2020,55(1):85-97
Ocean Science Journal - Seagrass meadows provide critical ecosystem services for coastal areas, e.g., as nursery habitats for various fish species, help with water filtration of suspended sediment,... 相似文献
57.
Chris Flynn J. Sommer-Larsen B. Fuchs David S. Graff Samir Salim 《Monthly notices of the Royal Astronomical Society》2001,322(3):553-560
Ibata et al. have recently discovered very faint, moving objects in the Hubble Deep Field (HDF). The number, apparent magnitudes and proper motions of these objects are consistent with old white dwarfs making up part of the Galactic dark halo. We review a number of ground-based proper motion surveys in which nearby dark-halo white dwarfs might be present, if they have the colours and absolute magnitudes proposed. No such objects have been found, whereas we argue here that several times more would be expected than in the HDF. We conclude that it is unlikely that hydrogen-atmosphere white dwarfs make up a significant fraction of the Galactic dark matter. No limits can be placed as yet on helium-atmosphere dwarfs from optical searches. 相似文献
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Saif Salim Al-Qaydi 《GeoJournal》1999,47(4):583-586
Within universities there has developed a clear theoretical convergence between Geographical Information Systems (GIS) and
geography (Antenuccl, 1991). Studies have revealed that one of the qualified departments to teach GIS within universities
is the geography department. This study focuses on: the importance of establishing GIS as a major curriculum element within
universities. In geography departments, economic geography students require a strong statistical/mathematical background to
allow them to work with major databases. They should know how to design a specific database for economic activities, such
as agriculture and manufacturing, and tertiary industry and how to relate this database to a map, so that changes can be monitored
more accurately. In any aspect of geography spatial location is a key factor and GIS allows spatial patterns to be interpreted
with great facility. Therefore it is important that students have a good knowledge not only of computers and related software
on economic geography, but also on GIS systems (Burrough, 1993). The work of geography students from the United Arab Emirates
(UAE) and other Gulf Co-operation Council (GCC) geography departments is examined to evaluate the importance of training in
GIS technology. This paper evaluates the effects of implementing GIS as a tool in teaching economic geography. At present
there are 15 geography departments in the GCC which offer economic geography. Of those 15 departments, only 3 provide GIS
courses within their curriculum, and 4 have basic equipment, although 6 additional departments are to introduce GIS in the
near future.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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B. H. Niazi M. Athar M. Salim J. Rozema 《International Journal of Environmental Science and Technology》2005,2(2):113-120
Growth and ionic relations of fodderbeet (Beta vulgaris) and seabeet (B.maritima) were studied in a greenhouse experiment using garden soil salinized with 200 mM NaCl. Both the species tolerated salinity level of 200 mM NaCl, but seabeet performed better than fodderbeet. Fresh weight of shoot increased significantly (P< 0.01) under higher salt concentration in both the species. Fodderbeet accumulated more biomass under saline conditions than seabeet. Salt treated plants accumulated significantly higher Na+ and CI? content in shoot compared to untreated control plants. Chloride (CI?) of seabeet root was significantly higher than shoot; however, chloride content of shoot was significantly lower in fodderbeet. The concentration of these ions was comparatively higher in seabeet root than fodderbeet in the later growth period. Potassium K+ content was low and revealed antagonistic effect with that of Na+ content. Calcium (Ca+2) ions were not significantly absorbed by shoot of both species. A significant effect of treatment by the root has been observed in both species. Magnesium (Mg+2) content of shoot were increased with the time. Seabeet has absorbed more Mg+2 than fodderbeet. The fodderbeet showed a significant salt tolerance during five week growth period. Seabeet is comparatively more salt tolerant. Domesticated cultivars of fodderbeet like Majorai have considerable adaptability in the inland salt affected areas of Pakistan. 相似文献