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991.
992.
Glauconitic minerals range from green smectite to 10Å glauconite, occur mainly in peloids (most of which were fecal pellets), and apparently were produced largely by neoformation replacing several kinds of substrate. Chamositic minerals, berthierine and chamosite, occur in Recent and ancient peloids, but mostly in ancient ooids, and they developed by alteration of a precursor Al-rich clay mineral. Ooid sheaths were built by rolling of cores on ue sea floor. Glauconitic greensands and chamositic oolitic ironstones are condensed sequences deposited as sandwaves during long periods of reduced influx of sediment. Some are associated with hardgrounds. 相似文献
993.
V. B. Titov 《Physical Oceanography》1993,4(1):63-69
Average and extreme values of the current velocity, seawater temperature, and their standard deviations are considered on the basis of measurements carried out at three moorings deployed in the Florida Strait. The contributions of the low-frequency (synoptic) and mesoscale variations of currents and the seawater temperature to their temporal variability are estimated. The kinetic energy values of the averaged current and the synoptic and mesoscale variations are given. Their contributions to the general (total) kinetic energy of currents are determined. It is shown that the pulsations of the north-east trade wind can be one of the reasons for the synoptic variations in the field of currents and seawater temperature.Translated by Mikhail M. Trufanov. 相似文献
994.
B. S. Hart 《Geo-Marine Letters》1993,13(4):219-226
The Foreslope Hills are a series of ridges and troughs covering over 60 km2 of the sea floor at the base of the Fraser Delta slope. Internally, the hills consist of blocks of prodelta and delta slope sediment (> 10.6 km3) bounded by offshore dipping faults and shear planes. Stratification within each block generally dips landward, indicating rotational failure. The amount of downslope translation of delta slope sediments was relatively minor. Deformation is restricted to a deep structural trough, suggesting failure resulted from yielding of soft underlying (early Holocene) prodelta sediments in the trough. 相似文献
995.
996.
Non-specific immune response of greenback flounder, Rhombosolea tapirina, exposed to contaminated marine sediments was examined. Reference sediments from Port Sorell and contaminated sediments from Deceitful Cove, Tasmania, Australia were investigated. Hatchery-reared flounder were exposed to reference sediment, contaminated sediment or contaminated sediment and diet for 6 weeks. Phagocytic capacity and lysozyme response in flounder were examined on cessation of exposure trial. Significant differences were found in phagocytic capacity and lysozyme response between treatments. Exposure to contaminated sediment, irrespective of diet or benthic disturbance elicited inhibition of phagocytic efficiency in flounder. Disturbance of contaminated sediment stimulated lysozyme activity. The immune response in flounder indicates potential immunotoxicity of sediment from Deceitful Cove. 相似文献
997.
998.
We describe one of possible mechanisms of the formation of anomalies of the cloud field over the North Atlantic and Europe
by using, as an example, the processes developed in the Atlantic-European sector during the natural synoptic season in the
spring of 1996. It is shown that the anomalies of the cloud field can be classified with the use of the index of the North
Atlantic oscillation and the latitude of the center of the Azorean maximum.
Translated by Peter V. Malyshev and Dmitry V. Malyshev 相似文献
999.
Oceanology - In November 2020, the invasive ctenophore Beroe ovata Bruguière, 1789 was recorded in samples of gelatinous zooplankton from the northern and central parts of the Caspian Sea. The... 相似文献
1000.
Izvestiya, Atmospheric and Oceanic Physics - The model balance equation of turbulence is represented in the form of the first law of thermodynamics. The forms for entropy are derived with an... 相似文献