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Vol. 5 (2002 year), No. 1

Petrovsky M.N. and Vinogradov A.N.
Geological model of the late Archaean Porosozersky granitoid massif (the Kola Peninsula)

A new geological model has been presented for the late Archaean Porosozersky granitoid massif in the Kola Peninsula. Four stages has been recognized in the pluton history: the main intrusive phase at 2733 Ma, when the long rock series gabbrodiorite - quartz moncodiorite - granodiorite - granite was produced as a result of inter-chamber differentiation; small bodies and veins of leucogranites were formed at the second stage; then dykes of lamprophyres intruded at 2680 Ma, and pegmatites completed the massif formation. The upper limit of the massif consolidation has been evaluated as 2674 Ma, when alkaline granites of the West Keivy complex were penetrated into the Porosozersky pluton. Contrary to the published early classifications, the Porosozersky pluton has been classified as a homologue of the orogenic tonalite-granodiorite formations of active continental margins.

(in Russian, стр.8, fig. 5, tables. 0, ref 16, MS Word 95, MS Word 95 496 Kb)

Vol. 12 (2009 year), No. 4

Asming V.E., Baranov S.V., Vinogradov A.N., Vinigradov Yu.A.
Seasonal character of seismicity in the region of Spitsbergen Archipelago

Deposits and prospective occurrences of certain strategic species of minerals – Cu, Ni, Pt, Au and others – defined on the basis of the most important features of geodynamics and magmatism of various Neoarchean and Early Proterozoic formations of the Kola Province have been presented. Indicating isotopic characteristics of Pt-Pd and Cu-Ni ore-bearing basic intrusions (the Pana and Pechenga types respectively), which occurred in different epochs (stages) of the East-Scandinavian Large Igneous province (EScLIP) have been discussed.

(in Russian, стр.5, fig. 7, tables. 0, ref 2, Adobe PDF, Adobe PDF 0 Kb)

Vol. 15 (2012 year), No. 2

Vinogradov A.N., Baranov S.V.
Recent geodynamic regime of the Eurasia – North American interplate boundary: Evidences from seismology of Arctic

The paper considers seismological evidences on a geodynamic regime in the Arctic segment of the interplate boundary between Eurasian and North American lithosphere plates. A scope of earthquakes occurred in the Mon, Knipovich and Gakkel mid-ocean ridge belts (MORB) has been made, and distribution of double-couple (DC) and non-double-couple (NDC) sources has been evaluated. As revealed, the DC events, caused by shearing tectonic movements, prevail among earthquakes in all MORBs. In the Arctic MORBs with ultra low speed of spreading the NDC earthquakes, caused by normal rifting or volcanic eruptions, are responsible for 9 % seismic energy release only, whereas in the Mon Ridge (North Atlantic spreading belt with the average speed of extension about 3 cm per annum) their contribution is 5 times higher. Thus, the seismological data give evidences that the Arctic segment of the interplate boundary between Eurasian and North American lithosphere plates belongs recently to the transform geodynamic type, and only in the North Atlantics (within the Mon Ridge) a divergent type is still alive.

(in English, стр.4, fig. 2, tables. 1, ref 8, Adobe PDF, Adobe PDF 0 Kb)