English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

On the whole, a general object of interdisciplinary investigations is the development of a model of the structural-material evolution of the Laptev Sea geosystem as a junction between the Mid-Oceanic Ridge in the Arctic Ocean and structures of the Eurasian continent. In a wider sense, the model is to involve different geological components, such as tectonics, sedimentology, biostratigraphy, paleogeography, seismology, the formation of gaseous hydrates, etc., and to be based on a systematic approach. Research work will include the following: theoretic investigations (analysis of existing views and development of a common conceptual base, if possible); re-processing and re-interpretation of available information; appropriate minimum of extra field investigations, primarily on the northern shelf margin and continental slope; laboratory analysis of available and new stony material on an up-to-date level; Computer data processing and development of mathematical models of processes and objects. This new line of inquiry is planned as a joint correlation analysis of coeval bottom deposits of the Arctic and the Antarctic, aimed at correlating global natural events and revealing general regularities of sedimentogenesis under polar conditions. This line of research holds great promise for the future; it is, thus, of utmost importance to direct our attention to these questions at the outset. The geological history of the Laptev Sea The Laptev Sea shelf has been a key region of the Arctic at all Stages of its geological history, during which many global natural objects and phenomena are as though joined. Thus, at the pre-oceanic developrnent Stage, structures of the ancient Siberian platform are conjugated here with northeast mesozoids. During the opening of the Arctic Ocean a unique geological situation existed the mid-oceanic Gakkel Ridge was joined at its end with continental structures. In terms of present-day geography, the Laptev Sea is an interrnediate sea between the western and eastern Arctic and is the last sea in which the influence of warm Atlantic waters, whcih have influenced the Ivanov et al.: Evolution peculiarities of the Laptev Sea geosystem as a key region in the Arctic sea's hydrosphere and biota, can be observed. Stated differently, the Laptev Sea is a peculiar epicentre of natural phenomena, some of which have been fully explored and the majority of which call for further investigation. Therefore, it is no mere chance that the Institute of Arctic Geology, later reorganized as the VNII Okeangeologiya and its subordinated association "Sevmorgeologiya", at all times considered the Laptev Sea shelf as an object of paramount importance, whose difficult of access position was the only factor restricting large-scale investigations. Islands fringing the Laptev Sea and the shore have been charted by the Geological Survey on a scale of 1 : 1,000,000 and 1 :200,000. As early as the 195O1s, sampling of bottom sediments was begun directly in offshore areas. This collection is still being supplemented, although rather slowly. From the mid-60's On, air-landing gravimetric observations from ice have been carried out. The whole area has been covered by a small-scale aeromagnetic survey. This gives a first impression of the region's general structure. The non-anomalous slightly negative magnetic field evident here may point to the total warping of the crust without evidence of developed spreading. The Lena-Taimyr Zone of boundary basement uplifts which coincides with a chain of gravitational maximums is clearly discernible in the gravity field. The combined analysis of geophysical data has made it possible to establish a Moho discontinuity beneath the Laptev Sea shelf, bulging up to 30 m and showing an anomalous low boundary velocity (7.5 kmls) which conforms to the dis-consolidated mantle. Such a deep model is typical of development areas of continental riftogenesis. The structure of shelf sedimentary cover has been studied by seismic survey. DSS and CMRW investigations were performed by polar expeditions of "Sevmorgeologiya" in 1973, 1980 and 1985-86. Most recently, in 1986-90, the Murmansk Expedition conducted on the shelf and resulting in 4200 km of profiles MRW CDP has brought about a revolutionary change in our knowledge of shelf geological structure. Today we can take for granted that the lower ("pre-oceanic") structural stage shows a lateral-heterogenic structure and represents a junction of large crustal blocks, each representing a continuation of structures from adjacent land masses. The western block is a pericratonic continuation of the Siberian platform characterizd by an early Proterozoic basement. The total section (Riphean to Cretaceous) of the sedimentary cover is 9-1 1 km thick; and contains up to 12 refraction horizons. In the northwest early kimmerids with the reduced Jurassic-Cretaceous cover, no more than 2 km in thickness, extend onto the shelf Zone of Taimyr. The eastern block is an offshore continuation of mesozoids of the Verkhoyan-Chukotsk folded area. The sedimentary cover is represented merely by the syn-oceanic complex, 1 to 2 km thick, up to 5 km thick in grabens. Further to the northeast, the so far "enigmatic" Cotelnichesky massif is observed to extend onto the shelf. The Laptev Sea shelf exists as a single marginal continental plate and as a single sedimentation basin, but at the "syn-oceanic" development stage (Upper Cretaceous-Cenozoic). The ofnset of the formation of this covering ("syn-oceanic") structural stage is coincides with such events as the completion of Late Cimmerian onland folding and the opening of the Eurasian Ivanov et al.: Evolution peculiarities of the Laptev Sea geosystem as a key region in the Arctic

Russian-German Cooperation in the Siberian Shelf Seas: Geo-System Laptev Sea