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Vol. 10 (2007 year), No. 1

Guberman D.M., Larikova T.L., Morozov Yu.A., Smulskaya A.I., Sholpo V.N., Yakovlev Yu.N.
Structure and evolution of the Kola Superdeep Borehole geo-space based on results of the study of structural-material heterogeneities

Some aspects have been shown in the paper: a general characteristic of granite pegmatites cut by SG-3 and data on structural variations of their "end-to-end" pegmatite-forming minerals – feldspar, garnet and mica – depending on the depth of pegmatite occurrence. The existence of vertical geochemical zonality (VGZ) of pegmatite vein system (PVS) of KSDB is proved statistically (more than 300 monomineral samples). VGZ, which has complicated polystage reciprocal character, is caused by contrast migration of chemical elements – indicators (CEI) at free moving of pegmatite-forming environment within the geochemical stages of the system. The range of such migration for PVS from SG-3 achieves more than 3 km along the vertical, which has denied the existing idea about formation of similar PVS "in situ". VGZ is controlled by a pressure drop and temperature gradient. The latter is estimated by two-feldspathic equilibrium at 25?5°C/km. This feature characterizes thermal conditions of the Kola megablock in the Late Archaean that complies with the initial stage of the Baltic shield formation.

(in Russian, стр.17, fig. 15, tables. 1, ref 26, Adobe PDF, Adobe PDF 0 Kb)