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I. I. Likhanov P. S. Kozlov V. V. Reverdatto N. V. Popov 《Doklady Earth Sciences》2018,480(1):568-572
Petrogeochemical and geochronological study of boudined quartzite sandstones and tonalites, as well as host amphibolites, in the shear zone showed that potential sources of detrital zircons were Neoarchean–Paleoproterozoic rocks of the Angara–Kan block and products of their metamorphism. Interpretation of the available data does not confirm the inferred presence of the Early Precambrian basement of the Siberian Craton in the Transangara region. 相似文献
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I. I. Likhanov A. A. Ten V. A. Ananiev V. V. Reverdatto I. Memmi 《Mineralogy and Petrology》2001,71(1-2):51-65
Summary A new approach for deriving kinetic parameters of diffusion-controlled metamorphic reactions is described. It is based on
comparison of models of temperature field evolution near a cylindrical intrusion and observable chemical changes in biotite
at the contact aureole of the Kharlovo massif. Unlike other methods used to construct quantitative models of reactions which
produce distinctly expressed zoned microtextures, the proposed approach allows better understanding of the processes occurring
in texture-homogeneous rocks, where complete consumption of some reactant mineral phases prevent accurate reconstruction of
the metamorphic process. The calculations yielded estimates of the effective rates of metamorphic reactions (10−12 s−1) and the effective diffusion coefficient (5.29 × 10−16 cm2 s−1). These values are consistent with experimentally and theoretically derived estimates of solid-state diffusion, including
grain-boundary diffusion.
Received July 14, 1998; revised version accepted June 28, 2000 相似文献
Zusammenfassung Inverse Modellierung zur Bestimmung kinetischer Parameter diffusionskontrollierter metamorpher Reaktionen in der Kontaktaureole von Kharlovo (Südsibirien, Ru?land) Ein neuer Ansatz zur Herleitung kinetischer Parameter diffusionskontrollierter metamorpher Reaktionen wird beschrieben. Er basiert auf einem Vergleich der Modelle für die Temperaturentwicklung um eine zylindrische Intrusion mit beobachtbaren ?nderungen im Chemismus von Biotit in der Kontaktaureole des Kharlovo Massivs. Im Unterschied zu anderen Methoden, die quantitative Modelle von Reaktionen mit deutlich zonierten Mikrotexturen verwenden, erlaubt dieser Ansatz ein besseres Verst?ndnis der Prozesse in texturell homogenen Gesteinen, in denen die vollst?ndige Reaktion einiger Reaktanden (Mineralphasen) sonst die Rekonstruktion des Metamorphoseprozesses verhindert. Die Berechnungen erlauben eine Absch?tzung der metamorphen Reaktionsraten und des effektiven Diffusionskoeffizienten . Diese Werte sind mit experimentell und theoretisch ermittelten Werten der Diffusion in Festk?rpern, einschlie?lich der Diffusion entlang von Korngrenzen, konsistent.
Received July 14, 1998; revised version accepted June 28, 2000 相似文献
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I. I. Likhanov V. V. Reverdatto S. V. Zinov’ev A. D. Nozhkin 《Doklady Earth Sciences》2013,450(1):489-493
The age of the latest impulse of dynamometamorphic structural-compositional transformations (603–615 Ma) was established from the 40Ar-39Ar age of micas from balstomilonites of the Garevka metamorphic complex of the Yenisei Ridge confined to the Priyenisei shear zone. The age of these tectonic-thermal events marks the final stage of the Neoproterozoic evolution of the Yenisei Ridge related to the accretion of the Isakovka terrane to the western margin of the Siberian Craton. These results are in agreement with the age of metamorphic rocks of northwestern Prisayany, which are incorporated into the Sayany-Yenisei accretionary belt along with Yenisei Ridge. The conformable data on two regions indicate a global Vendian accretionary-collision event, which led to the formation of the Sayany-Yenisei accretionary belt, lateral thickening of the continental crust to the southwestern margin of the Siberian Craton, and its subsequent tectonic reworking. The synchronous Vendian orogenesis and consequence of the tectonic-thermal events along the periphery of the large Precambrian cratons of the Baltic and Siberia confirm their close spatial relation about 800 Ma ago, which agrees with contemporary paleomagnetic reconstructions. 相似文献
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I. I. Likhanov V. V. Reverdatto P. S. Kozlov A. E. Vershinin 《Doklady Earth Sciences》2011,436(2):213-218
Two successive phases of metamorphism can be recognized based on mineralogical and petrological observations coupled with
geothermobarometric estimates for chemical zoning in Fe- and Al-rich metapelites from the Teya crystalline rocks of the Transangarian
Yenisei Ridge. The first phase is marked by the formation of low-pressure regional metamorphic complexes of the andalusite-sillimanite
type (P = 3.9–5.1 kbar; T = 510–640°C), which were most likely related to the Middle Riphean Grenville events. In the second phase, metapelitic rocks
underwent Late Riphean medium-pressure collisional metamorphism of the kyanite-sillimanite type (P = 5.7–7.2 kbar, T = 660–700°C), which resulted locally in an increase in pressure in the vicinity of thrusts. These results suggest that medium-pressure
kyanite-bearing metapelitic rocks were formed as a result of collision-related metamorphism caused by thrusting of the Siberian
cratonal blocks onto the Yenisei Ridge in the vicinity of the Tatarka deep fault. 相似文献
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