202 



A. M. Alekseev et al. 



Figure 2 shows a KS map drawia from the average KS curves for a worldng 

 distance R = 3,000 m. There is a regular decrease in the KS values in 

 a north-westerly direction, corresponding to increase in the thickness of 

 the friable Meso-Cenezoic formations. On this background to the north 

 of L. Mikhailovskoe a local maximum of KS vakies is identifiable which is 

 an indication that the Paleozoic foundation is lifted up between the points 

 L. Mikhailovskoe and Epifanovsldi. This interpretation of the structure of 

 the Paleozoic rocks is supported by the vectors Aq (Fig. 3) for the same 

 working distance. 



DZ-59 



DZ-58 



DZ-50 



DZ-48 DZ-56 DZ-57 



Fig. 4. Curves for two-way probes along AB profile. 



As can be seen, the directions of the vectors Aq clearly characterize the 

 basic features of the surface of the Paleozoic foundations (remembering 

 that the vectors Aq indicate the direction in which the KS values decrease). 

 The presence of elevations in the top surface of the foundation are partic- 

 ularly well observed on comparing the plus and minus KS curves (Fig. 4). 

 Thus, on the AB profile, which intersects the zone of increased KS value, 

 there is a reversal of the plus and minus KS curves (DZ-58, DZ-59), 

 characteristic of a passage across the crest of the structure. On the DZ-58 

 the right-hand branch of the positive (south-west) curve, represented by 

 a continuous line, is placed above the right-hand branch of the negative 

 (north-east) curve, shown by a dotted line, which indicates a rise in the foun- 

 dation in a south-westerly direction. 



On the DZ-59, reverse relationships were observed, which indicate the 

 change in direction of dip of the foundation. Very characteristic are the 

 relationships of the right-hand branches of the curves DZ-48, DZ^9, 

 DZ-50, showing the presence of a depression in the surface of the founda- 

 tion -svith deepest part in the DZ^9 zone, where the right-hand bran- 

 ches of the positive and negative curves coincide almost completely. 



