The publication presents stress determinations from geological and kinematical indicators of tectonic stress fields, varying in ranks, for the Kola Peninsula. The objective is to determine possible mechanisms of formation of recent structures in the eastern segment of the Baltic shield and to forecast seismogenic and technogenic hazard of fracturing.The study is focused on the Kovdor and Khibin Paleozoic alkalineultrabasic blocks. Tectonic stresses are reconstructed by M.V. Gzovsky's method [1954; 1975] based on identification of conjugated shear systems. Neotectonic stresses are stud ied by the kinematic method [Gushchenko, 1979] on the basis of measurements of tectonic displacment vectors from slicken sides (Figure 2). Local stress data processed by the method for determination of general stress fields provide for reconstruc tion of main normal stresses which are arbitrarily considered as regional stresses [Sim, 1980; 2000. This study uses the method of bandpattern distribution of fracturing in fault zones [Danilovich, 1961] which determines the main displacement line on the fault plane.The study of the Zhelezny mining site (Kovdor block, Figures 3 and 4) revealed that elements of fractures of two differ ent ages (centroclinal fractures of the prototectonic genesis and fractures of later tectonic activation) are spatially overlap ping due to rock collapse and lacking stability of benches. Numerous inversions and changes of kinematics of relative dis placements were reviewed. It was observed that the southeastern wall of the quarry collapsed due to local extension ( Fig. 6B and Photos 1 and 2), and a large fault, i.e. a prototectonic fracture, was dipping towards the quarry. Based on the analyses of local stresses at various points of the quarry (Table 1), two 'regional' stress fields can be revealed (Figures 7 and 8). The first paleostess field was associated with reverse faults of the WNW subhorizontal axis of compression and the steeply dipping axis of extension. The second field was related to shear faults; its axis of compression maintained the WNW orientation, while the extension axis was reoriented, and the axis of extension attained submeridional position and a less steep dip. The second field is younger as suggested by traces of two displacements identified on several planes, the youngest of which are shears.From the analysis of measurements taken at 273 planes with striations, it is evident that striations are distributed in a bandshape pattern. The band of fractures is coincident with the plane of the transition axis of the young 'regional field (Fig ure 9); main maximums of density of the planes with striations are symmetrically scattered in a fanlike pattern from the axis of compression and extension of this field. Generally, the striations reflect traces of younger displacements, and their consis tency with the axes of the young field supports our conclusions on age relationships between the two 'regional' fields. Four major stages of deformation of the Kovdor block under study are di...
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