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Evolution of the Timan–Pechora and South Barents Sea basins
- N. O'LEARY, N. WHITE, S. TULL, V. BASHILOV, V. KUPRIN, L. NATAPOV, D. MACDONALD
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- Journal:
- Geological Magazine / Volume 141 / Issue 2 / March 2004
- Published online by Cambridge University Press:
- 21 April 2004, pp. 141-160
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We have analysed 129 stratigraphic sections from the Timan–Pechora basin, from its adjacent continental shelf and from the South Barents Sea basin, in order to determine whether existing models of extensional sedimentary basin formation can be applied to these intracratonic basins or whether new mechanisms of formation need to be invoked. The subsidence history of each section has been calculated using standard backstripping techniques. An inverse model, based on finite-duration lithospheric stretching, has then been used to calculate the distribution of strain rate as a function of time required to fit each subsidence profile. Results demonstrate an excellent fit between theory and observation. By combining our analysis with independent field-based and geophysical observations, we show that the Timan–Pechora basin underwent at least four phases of mild lithospheric stretching during the Phanerozoic (β<1.2). These phases occurred in Ordovician, Late Ordovician–Silurian, Middle–Late Devonian and Permian–Early Triassic times. Growth on normal faults, episodes of volcanic activity and regional considerations provide corroborative support for the existence of all four phases. Although less well constrained, subsidence data from the South Barents Sea basin are consistent with a similar Early–Middle Palaeozoic history. The main difference is that Permian–Early Triassic extension is substantially greater than that seen onshore. This similarity implies structural connectivity throughout their respective evolutions. Finally, subsidence modelling demonstrates that rapid foreland basin formation, associated with the Uralian Orogeny, was initiated in Permo-Triassic times and is confined to the eastern margin of the Timan–Pechora basin. Coeval foreland subsidence does not occur on the eastern margin of the South Barents Sea basin, supporting the allochthonous nature of Novaya Zemlya. The most puzzling result is the existence of simultaneous lithospheric extension and foreland loading in Permian–Early Triassic times. This juxtaposition is most clearly seen within the Timan–Pechora basin itself and suggests that convective drawdown may play a role in foreland basin formation.
A Bibliography of Soviet Studies of the Ancient Cultures of Latin America
- V. A. Bashilov, V. I. Gulyaev
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- Journal:
- Latin American Antiquity / Volume 1 / Issue 1 / March 1990
- Published online by Cambridge University Press:
- 20 January 2017, pp. 5-22
- Print publication:
- March 1990
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The study in the Union of Soviet Socialist Republics of the earliest history of native Latin Americans falls into two distinct periods. The first, associated with an interest in the ancient Mexican and Peruvian civilizations, can be divided into two stages: the 1920s to the early 1940s, when Soviet scholars first acquainted themselves with antiquities from the region and used them for historical parallels; and the late 1940s and early 1950s, when Soviet historians turned to an analysis of Latin American materials. The second period went through three stages: the first, from the early 1950s to the early 1960s, mainly was dominated by Yury Knorozov, who was engaged in deciphering the language of the Maya, and Rostislav Kinzhalov, who studied their art and culture. During the second stage, the early 1960s to the mid-1970s, more scholars and research institutions undertook studies of the early cultures of Latin America. The thematic range became wider as well, covering—besides Mesoamerica and the central Andean region—the Intermediate region and the Caribbean. The third stage, which started in the late 1970s and continues to the present day, witnesses ethnographers and archaeologists pooling their efforts in studying the region. There were several conferences in which specialists engaged in various fields of Latin American studies participated. Their contacts with foreign colleagues became wider; Soviet archaeologists and ethnologists took part in fieldwork in Latin America. The primary aims today are to introduce Soviet readers to archaeological materials from a number of cultural-historical regions (such as the southern fringes of Mesoamerica, Amazonia, the southern Andes, etc.), to detail Soviet studies of cultural complexes and historical processes in ancient America, and to compare them to the processes that took place in the Old World, with the aim of establishing shared historical “laws” and patterns.