Lithogeochemical features of the Vendian mudstones and silty mudstones taken from Borehole Keltma 1 in the southern part of the Vychegda trough of the Mezen syneclise are discussed. It is shown that ...fine-grained clastic rocks of the Ust-Pinega, Krasavino, and Mezen formations have similar chemical compositions, suggesting their accumulation in sufficiently similar settings. The main part of the studied samples has K
2
O/Al
2
O
3
< 0.4. This fact, in combination with the absence of TM-FM and NPM-HM correlations, indicates a significant contribution of recycled aluminosiliciclastics in their composition. At the same time, the absence of correlation between CIA and indicator ratios of rock composition in the paleodrainage basins, such as Th/Cr and Th/Sc, indicates that CIA and some other lithochemical indicators appropriately reflect the paleoclimatic conditions in source areas surrounding a basin. The CIA value in most of the analyzed samples is no more than 70. Thus, the Keltma section is similar to Upper Vendian sequences of the Kvarkush-Kamennogorsk anticlinorium and the Shkapovo-Shikhany depression. It has been established that felsic and intermediate magmatic rocks coupled with a significant contribution of quartz-rich sediments served as the source of fine aluminosiliciclastics for the southern Vychegda trough during the Vendian. High Ce/Cr values in the mudstones and silty mudstones suggest that the geochemically primitive Archean protoliths were not involved in the washout. In the SiO
2
-K
2
O/Na
2
O diagram, the Vendian mudstones and silty mudstones are plotted in the field of sediments of active continental margins. Typical low values of Mo/Mn and some other redox indices in these rocks indicate that oxidizing environment predominated in bottom waters of the sedimentation basin during the entire Vendian. Analysis of variations of the lithochemical indicators upward the Vendian sedimentary successions in borehole Keltma 1 made it possible to divide the section into three sequences of different lithofacies and paleontological compositions.
Sediment successions from the Kanin Peninsula and Chyoshskaya Bay in northwestern Russia contain information on the marginal behaviour of all major ice sheets centred in Scandinavia, the Barents Sea ...and the Kara Sea during the Eemian‐Weichselian. Extensive luminescence dating of regional lithostratigraphical units, supported by biostratigraphical evidence, identifies four major ice advances at 100–90, 70–65, 55–45 and 20–18 kyr ago interbedded with lacustrine, glaciolacustrine and marine sediments. The widespread occurrence of marine tidal sediments deposited c. 65–60 kyr ago allows a stratigraphical division of the Middle Weichselian Barents Sea and Kara Sea ice sheets into two shelf‐based glaciations separated by almost complete deglaciation. The first ice dispersal centre was in the Barents Sea and thereafter in the Kara Sea. It is possible to extract both flow patterns from ice marginal landforms inside the southward termination. Accordingly, it is proposed that the Markhida line and its western continuation are asynchronous and originate from two separate glaciations before and after the marine transgression. The marine sedimentation occurred during a eustatic sea‐level rise of up to 20 m/1000 yr, i.e. the Mezen Transgression. We speculate that the rapid eustatic sea‐level rise triggered a collapse of the Barents Sea Ice Sheet at the MIS (Marine Isotope Stage) 4 to 3 transition. This is motivated by lack of an early marine highstand, the timing of events, and the marginal position of Arkhangelsk relative to open marine conditions.
A section, almost 20 km long and up to 80 m high, through alternating layers of diamict and sorted sediments is superbly exposed on the north coast of the Kanin Peninsula, northwestern Russia. The ...diamicts represent multiple glacial advances by the Barents Sea and the Kara Sea ice sheets during the Weichselian. The diamicts and stratigraphically older lacustrine, fluvial and shallow marine sediments have been thrust as nappes by the Barents Sea and Kara Sea ice sheets. Based on stratigraphic position, OSL dating, sea level information and pollen, it is evident that the sorted sediments were deposited in the Late Eemian‐Early Weichselian. Sedimentation started in lake basins and continued in shallow marine embayments when the lakes opened to the sea. The observed transition from lacustrine to shallow marine sedimentation could represent coastal retreat during stable or rising sea level.
This work reports the first results of isotopic geo-chronological study of detrital zircons from sandstones of the Late Precambrian Enganepe unit, which belongs to the Pre-UralidesTimanides exposed ...in the core of large Hercynian anticline in the Enganepe Uplift, western Polar Urals. The presence of a tuffaceous admixture in sandstones indicates the volcanic origin of some zircons. Data suggest that they were left in the sediments as syngenetic tephra during volcanic eruptions, which produced a basaltbasaltic andesite andesitedaciterhyolite volcanic complex (Bedamel Group) close in age to the Enganepe unit.
Scholars of Holocaust literary narratives have identified the ways in which the uses of language, memory, and narrative/ testimony have shifted in these texts from realistic modes of representation ...to more hybrid and metafictional considerations of this epochal event. Independently, critics working within science fiction (sf) have examined the ethical underpinnings of the genre’s construction and indicated potential reasons for the proliferation of sf in the twentieth century vis-à-vis trauma theory and the particular historical and technological climate of the era. In an effort to examine Holocaust history and memory – particularly, the force of the Holocaust and its impact on Jewish populations born and raised in the United States – Philip Roth increasingly turns to sf tropes and constructions as he explores the Holocaust more and more directly in three major works: The Ghost Writer (1979), Operation Shylock (1993), and, finally, his alternate history text The Plot Against America (2004). As the American-born protagonists in each of these texts confront the existential destruction of 20th century Jewishness and the widening gyre of history, Roth introduces and increasingly orients his texts around classic sf tropes to explore the breakdown of representational modalities and material cause which mark his generation’s conception of the effects of the Holocaust, as well as the perception of borders within his generation’s conception of Jewishness. Roth’s use of cognitive novelty and alternate history reflect the New Jersey-born author’s coming to terms with questions of “us vs. them” regarding American and European Jewry, particularly in light of arguments made by scholars such as Dominick LaCapra and Giorgio Agamben with respect to the limitations of traditional eyewitness testimony and narrative forms following the Holocaust. Roth and his (self-styled) protagonists grapple with the fundamental paradox of representing the unrepresentable – responding to an event that has broken down the logics of comprehension and expression – and how these pressures are to be represented or explored by American Jews whose understanding of their relationship to the Holocaust and their fellow Jew is one of diminished distances between the US and what happened “over there.”
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