A Vendian–Cambrian boundary succession from the northwestern margin of the Siberian Platform: stratigraphy, palaeontology, chemostratigraphy and correlation

1998 ◽  
Vol 135 (4) ◽  
pp. 473-494 ◽  
Author(s):  
JULIE K. BARTLEY ◽  
MICHAEL POPE ◽  
ANDREW H. KNOLL ◽  
MIKHAIL A. SEMIKHATOV ◽  
PETER YU. PETROV
Keyword(s):  
Siberian Platform ◽  
Western Siberia ◽  
World Ocean ◽  
Environmental Evolution ◽  
Carbon Isotopic ◽  
Reference Sections ◽  
The World ◽  
Northwestern Margin

Siberia contains several key reference sections for studies of biological and environmental evolution across the Proterozoic–Phanerozoic transition. The Platonovskaya Formation, exposed in the Turukhansk region of western Siberia, is an uppermost Proterozoic to Cambrian succession whose trace and body fossils place broad limits on the age of deposition, but do not permit detailed correlation with boundary successions elsewhere. In contrast, a striking negative carbon isotopic excursion in the lower part of the Platonovskaya Formation permits precise chemostratigraphic correlation with uppermost Yudomian successions in Siberia, and possibly worldwide. In addition to providing a tool for correlation, the isotopic excursion preserved in the Platonovskaya and contemporaneous successions documents a major biogeochemical event, likely involving the world ocean. The excursion coincides with the palaeontological breakpoint between Ediacaran- and Cambrian-style assemblages, suggesting a role for biogeochemical change in evolutionary events near the Proterozoic–Cambrian boundary.

scholarly journals The SPICE carbon isotope excursion in Siberia: a combined study of the upper Middle Cambrian–lowermost Ordovician Kulyumbe River section, northwestern Siberian Platform

2008 ◽  
Vol 145 (5) ◽  
pp. 609-622 ◽  
Author(s):  
ARTEM KOUCHINSKY ◽  
STEFAN BENGTSON ◽  
YVES GALLET ◽  
IGOR KOROVNIKOV ◽  
VLADIMIR PAVLOV ◽  
...  
Keyword(s):  
Carbon Isotope ◽  
Siberian Platform ◽  
Total Duration ◽  
Local Maximum ◽  
Magnetic Polarity ◽  
Middle Cambrian ◽  
Upper Cambrian ◽  
Carbon Isotopic ◽  
Reversal Frequency ◽  
Northwestern Margin

AbstractAn integrated, high-resolution chemostratigraphic (C, O and Sr isotopes) and magnetostratigraphic study through the upper Middle Cambrian–lowermost Ordovician shallow-marine carbonates of the northwestern margin of the Siberian Platform is reported. The interval was analysed at the Kulyumbe section, which is exposed along the Kulyumbe River, an eastern tributary of the Enisej River. It comprises the upper Ust'-Brus, Labaz, Orakta, Kulyumbe, Ujgur and lower Iltyk formations and includes the Steptoean positive carbon isotopic excursion (SPICE) studied here in detail from upper Cambrian carbonates of the Siberian Platform for the first time. The peak of the excursion, showing δ13C positive values as high as +4.6‰ and least-altered87Sr/86Sr ratios of 0.70909, is reported herein from the Yurakhian Horizon of the Kulyumbe Formation. The stratigraphic position of the SPICE excursion does not support traditional correlation of the boundary between the Orakta and Labaz formations at the Kulyumbe River with its supposedly equivalent level in Australia, Laurentia, South China and Kazakhstan, where theGlyptagnostus stolidotusandG. reticulatusbiozones are known to immediately precede the SPICE excursion and span the Middle–Upper Cambrian boundary. The Cambrian–Ordovician boundary is probably situated in the middle Nyajan Horizon of the Iltyk Formation, in which carbon isotope values show a local maximum below a decrease in the upper part of the Nyajan Horizon, attributed herein to the Tremadocian Stage. A refined magnetic polarity sequence confirms that the geomagnetic reversal frequency was very high during Middle Cambrian times at 7–10 reversals per Ma, assuming a total duration of about 10 Ma and up to 100 magnetic intervals in the Middle Cambrian. By contrast, the sequence attributed herein to the Upper Cambrian on chemostratigraphic grounds contains only 10–11 magnetic intervals.

Kazakhstan’s Economic Growth in the Context of the World Economy

2006 ◽  
pp. 133-146 ◽  
Author(s):  
K. Arystanbekov
Keyword(s):  
Economic Growth ◽  
Economic Policy ◽  
World Economy ◽  
World Ocean ◽  
Direct Access ◽  
Crude Petroleum ◽  
Nation States ◽  
The World ◽  
The Relationship

Kazakhstan’s economic policy results in 1995-2005 are considered in the article. In particular, the analysis of the relationship between economic growth and some indicators of nation states - population, territory, direct access to the World Ocean, and extraction of crude petroleum - is presented. Basic problems in the sphere of economic policy in Kazakhstan are formulated.

ON EVALUATION OF THE ROLE OF THERMAL AND WIND FACTORS FOR A PHYSICAL MODEL OF THE WORLD OCEAN GENERAL CIRCULATION SYSTEM

2019 ◽  
Vol 47 (3) ◽  
pp. 80-91
Author(s):  
V. G. Neiman
Keyword(s):  
Physical Model ◽  
Ocean Circulation ◽  
General Circulation ◽  
World Ocean ◽  
Circulation System ◽  
The Public ◽  
The World ◽  
Almost All ◽  
Conceptual Foundations

The main content of the work consists of certain systematization and addition of longexisting, but eventually deformed and partly lost qualitative ideas about the role of thermal and wind factors that determine the physical mechanism of the World Ocean’s General Circulation System (OGCS). It is noted that the conceptual foundations of the theory of the OGCS in one form or another are contained in the works of many well-known hydrophysicists of the last century, but the aggregate, logically coherent description of the key factors determining the physical model of the OGCS in the public literature is not so easy to find. An attempt is made to clarify and concretize some general ideas about the two key blocks that form the basis of an adequate physical model of the system of oceanic water masses motion in a climatic scale. Attention is drawn to the fact that when analyzing the OGCS it is necessary to take into account not only immediate but also indirect effects of thermal and wind factors on the ocean surface. In conclusion, it is noted that, in the end, by the uneven flow of heat to the surface of the ocean can be explained the nature of both external and almost all internal factors, in one way or another contributing to the excitation of the general, or climatic, ocean circulation.

Revised Chronology of Neogene DSDP Holes from the World Ocean

1995 ◽  
Author(s):  
D. Lazarus ◽  
C. Spencer-Cervato ◽  
M. Pika-Biolzi ◽  
J.P. Beckmann ◽  
K. von Salis ◽  
...  
Keyword(s):  
World Ocean ◽  
The World

Comparative analysis and interpretation of grace and grace-fo data

2020 ◽  
Vol 4 ◽  
pp. 101-106
Author(s):  
Konstantin Simonov ◽  
◽  
Alexander Matsulev
Keyword(s):  
Comparative Analysis ◽  
World Ocean ◽  
Satellite System ◽  
Data Archive ◽  
Space Systems ◽  
Satellite Measurements ◽  
Digital Maps ◽  
The World ◽  
Grace Mission ◽  
Anomalous State

The study is devoted to the analysis of the features of the change in the Equivalent Water Height (EWH) parameter over the geoid based on satellite measurements of space systems. The study used the GRACE and GRACE-FO satellite data archive. The assessment was carried out on Earth as a whole, including land areas and the World Ocean. Interpretation of the anomalous state of the geoenvironment is performed using digital maps of the spatial distribution of the EWH parameter based on the histogram approach and correlation analysis. Also, a comparative analysis of the studied data from the GRACE mission and data from the new GRACE-FO satellite system launched into orbit in the summer of 2018 was carried out.

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