Transport and deposition of mud in deep‐water environments: Processes and stratigraphic implications     

Kvin Boulesteix  Miquel Poyatos‐Mor  Stephen S. Flint  Kevin G. Taylor  David M. Hodgson  Stephen T. Hasiotis 《Sedimentology》2019,66(7):2894-2925

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FT-IR study of the effect of lead and the influence of chelating agents, DMSA and D-Penicillamine, on the biochemical contents of brain tissues of Catla catla fingerlings     

PL. RM. Palaniappan  N. Krishnakumar  M. Vadivelu 《Aquatic Sciences - Research Across Boundaries》2008,70(3):314-322

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Earthquakes from 1820 to 1936 in Grahamstown and surroundings (Eastern Cape Province,South Africa)     

Paola Albini  Fleur O. Strasser  Nicolette S. Flint 《Bulletin of Earthquake Engineering》2014,12(1):45-78

The seismicity of Grahamstown, in the Eastern Cape Province of South Africa, for the years between 1820 and 1936 is investigated with recourse to contemporaneous documentary sources, leading to the development of a seismic history incorporating consideration of the broader geo-political context. Individual studies of five regional events that were felt in Grahamstown during that period, and of one that was not, are presented. Each study includes the development of a full set of intensity data points, which are used to determine reappraised epicentral locations and magnitudes, some of which differ significantly from previously listed parameters. The results thus obtained highlight the value of seeking out additional contemporary sources from different language groups when revisiting the source parameters of earthquakes for which no or only very limited instrumental information is available.  相似文献   

A site‐consistent method to quantify sufficiency of alternative IMs in relation to PSDA          下载免费PDF全文

Somayajulu L. N. Dhulipala  Adrian Rodriguez‐Marek  Shyam Ranganathan  Madeleine M. Flint 《地震工程与结构动力学》2018,47(2):377-396

In probabilistic seismic demand analysis, evaluation of the sufficiency of an intensity measure (IM) is an important criterion to avoid biased assessment of the demand hazard. However, there exists no metric to quantify the degree of sufficiency as per the criterion of Luco and Cornell (2007). This paper proposes a site‐specific unified measure for degree of sufficiency from all seismological parameters under consideration using a total information gain metric. This unified metric for sufficiency supports not only comparison of the performance of different IMs given a response quantity but also assessment of the performance of a particular IM across different response quantities. The proposed sufficiency metric was evaluated for a 4‐story steel moment frame building, and the influence of ground motion selection on the degree of sufficiency was investigated. It was observed that ground motion selection can have a significant impact on IM sufficiency. Because computing the total information gain requires continuous deaggregation across the IM space, an approximate deaggregation technique that allows for a more practical estimation of marginal deaggregation probabilities is proposed. It is expected that the total information gain metric proposed in this paper will aid in understanding the efficiency‐sufficiency relation, thus enabling the selection of a proper scalar IM for a given site and application in probabilistic seismic demand analysis.  相似文献   

Zooplankton in Bays of the Novaya Zemlya Archipelago: Composition,Distribution, and Role in Phytoplankton Grazing and Biosedimentation     

Amelina  A. B.  Drits  A. V.  Sergeeva  V. M.  Soloviyev  K. A.  Belyaev  N. A.  Dara  O. M.  Demidov  A. B.  Flint  M. V. 《Oceanology》2018,58(6):825-837

Oceanology - The zooplankton community in two bays of the eastern coast of the Novaya Zemlya archipelago (Blagopoluchiya Bay and Tsivolki Bay) has been studied for the first time. Copepods of the...  相似文献   

Investigations of the Ecosystem in the Atlantic Sector of Antarctica (Cruise 79 of the R/V Akademik Mstislav Keldysh)     

Morozov  E. G.  Spiridonov  V. A.  Molodtsova  T. N.  Frey  D. I.  Demidova  T. A.  Flint  M. V. 《Oceanology》2020,60(5):721-723

Oceanology - Field works on cruise 79 of the R/V Akademik Mstislav Keldysh aimed at investigating the ecosystems in the Atlantic sector of Antarctica were conducted from January 16 to March 1,...  相似文献   

Biochemical Composition and Energy Content in the Zooplankton of the Kara Sea     

Lobus  N. V.  Flint  M. V.  Flerova  E. A.  Shcheglova  Y. V. 《Oceanology》2020,60(6):778-786

Oceanology - This article presents a data set on ash, proteins, lipids, carbohydrates, chitin, organic carbon (OC), total nitrogen (TN) and total phosphorus (TP) contents, macronutrients ratio (C,...  相似文献   

The role of zooplankton in the transformation of the organic matter in the Ob estuary,on the shelf,and in the deep regions of the Kara Sea     

E. G. Arashkevich  M. V. Flint  A. B. Nikishina  A. F. Pasternak  A. G. Timonin  J. V. Vasilieva  S. A. Mosharov  K. A. Soloviev 《Oceanology》2010,50(5):780-792

The data for the present study were collected at 20 sampling stations in the Kara Sea along the transect from the Ob estuary to the deep sea St. Anna Trough in September 2007. Based on the hydrophysical features, the distribution of the Chl a, and the primary production, we distinguished six habitats: the river, estuary, inner and outer shelf, continental slope, and trough. The impact of the small-size (<0.5 mm) and large-size (>0.5 mm) fractions of the zooplankton on the phytoplankton’s organic carbon in the different regions of the Kara Sea was estimated. The ingestion rate was assessed using the analysis of the gut fluorescence content and the gut evacuation rate. The zooplankton grazed 1–2% of the phytoplankton biomass in the river and estuary; 3.5% over the shelf; and 6 and 10% in the regions of the trough and slope, respectively. The grazing impact of the small-sized zooplankton increased from the river zone to the deep regions (from 1 to 90%) along with their share in the total zooplankton abundance (from 18 to 95%). From 72 to 86% of the primary production was grazed over the shelf and slope. The primary production did not cover the feeding requirements of the zooplankton in the estuarine regions and St. Anna Trough in the autumn. In the estuarine regions, the major portion of the organic matter settles on the bottom due to the strong inflow of the allochthonous matter and the relatively low zooplankton grazing.  相似文献   

Geochronological and isotopic constraints on Palaeoproterozoic skarn base metal mineralisation in the central Gawler Craton, South Australia   总被引：1，自引：0，他引：1  

Anthony Reid  Richard Flint  Roland Maas  Katherine Howard  Elena Belousova 《Ore Geology Reviews》2009,36(4):350-362

The mineralisation potential of Palaeoproterozoic strata from the central Gawler Craton, South Australia, is poorly known. This study defines the timing of Zn-rich skarn formation within Palaeoproterozoic calcsilicate and highlights this as a new mineralisation style for the Gawler Craton. Sulphides within the garnet–diopside skarn in the No. 17 Bore Prospect are predominantly in the form of sphalerite, associated with galena, minor chalcopyrite, pyrrhotite and pyrite. Sulphide is present in disseminated form and as a coarse-grained sulphide within a sericite-rich cavity-fill. Mineralisation is inferred to have formed at 1710 ± 16 Ma through a Sm–Nd isochron from garnet and diopside aliquots. A weakly mineralised and altered granite immediately below the calcsilicate skarn crystallised at 1729 ± 13 Ma (LA-ICPMS U–Pb zircon), within error of the skarn mineralisation. The skarn is interpreted to have formed through the initiation of fluid circulation as a result of high-level granite emplacement within the Palaeoproterozoic strata. Exploration for skarn Zn–Pb deposits such as the No. 17 Bore Prospect is assisted by their geophysical properties.  相似文献   

Trophic cascades and future harmful algal blooms within ice-free Arctic Seas north of Bering Strait: A simulation analysis     

John J. Walsh  Dwight A. Dieterle  F. Robert Chen  Jason M. Lenes  Wieslaw Maslowski  John J. Cassano  Terry E. Whitledge  Dean Stockwell  Mikhail Flint  Irina N. Sukhanova  John Christensen 《Progress in Oceanography》2011,91(3):312-343

Within larger ice-free regions of the western Arctic Seas, subject to ongoing trophic cascades induced by past overfishing, as well as to possible future eutrophication of the drainage basins of the Yukon and Mackenzie Rivers, prior very toxic harmful algal blooms (HABs) – first associated with ∼100 human deaths near Sitka, Alaska in 1799 – may soon expand. Blooms of calcareous coccolithophores in the Bering Sea during 1997–1998 were non-toxic harbingers of the subsequent increments of other non-siliceous phytoplankton. But, now saxitoxic dinoflagellates, e.g. Alexandrium tamarense, were instead found by us within the adjacent downstream Chukchi Sea during SBI cruises of 2002 and 2003. A previous complex, coupled biophysical model had been validated earlier by ship-board observations from the Chukchi/Beaufort Seas during the summer of 2002. With inclusion of phosphorus as another chemical state variable to modulate additional competition by recently observed nitrogen-fixers, we now explore here the possible consequences of altered composition of dominant phytoplankton functional groups [diatoms, microflagellates, prymnesiophyte Phaeocystis colonies, coccolithophores, diazotrophs, and dinoflagellates] in relation to increases of the toxic A. tamarense, responding to relaxation of grazing pressure by herbivores north of Bering Strait as part of a continuing trophic cascade. Model formulation was guided by validation observations obtained during 2002–2004 from: cruises of the SBI, CHINARE, and CASES programs; moored arrays in Bering Strait; other RUSALCA cruises around Wrangel Island; and SBI helicopter surveys of the shelf-break regions of the Arctic basin. Our year-long model scenarios during 2002–2003 indicate that post bloom silica-limitation of diatoms, after smaller simulated spring grazing losses, led to subsequent competitive advantages in summer for the coccolithophores, dinoflagellates, and diazotrophs. Immediate top-down control is exerted by imposed grazing pressures of the model’s herbivores and bottom-up control is also effected by light-, nitrate-, ammonium-, silicate-, and phosphate-modulated competition among the six functional groups of the simulated phytoplankton community. Similar to the history of the southern North Sea adjacent to the Rhine River, possible farming of northwestern Alaska and Canada, in conjunction with other human activities of ice retreat and overfishing, may lead to future exacerbations of poisonous phytoplankton. These potential killers include both toxic dinoflagellate and diazotroph HABs, deadly to terrestrial and marine mammals, as well as those of prymnesiophytes, some of which have already foamed beaches, while others have killed fishes of European waters.  相似文献