1897.] NATURAL SCIENCES OF PHILADELPHIA. 405 



GEOLOGICAL SECTION FROM MOSCOW TO SIBERIA AND RETURN. 

 BY Dr. PERSIFOR FRAZER. 



The accompanying notes were made during the excursion to the 

 Ourals which was arranged by the local committee for a certain 

 number of Geologists before the business session of the Seventh 

 International Geological Congress at St. Petersburg. In addition 

 to the complete preparations for the expedition, carefully edited 

 brochures of its different parts were printed by those Russian 

 geologists who had devoted especial study to the districts. So far 

 as the excursionists were concerned the section was necessarily one 

 of inspection and verification of what had been done, rather than 

 one of exploration for the establishment of new facts, and con- 

 sequently, in a description like the following, the data secured in 

 the years of long and patient investigation by the Geological Survey 

 of Russia have been used so far as this epitome required them. 



The lessons learned by the numerous, long and well planned 

 excursions made in connection with the Congress, begin appropriately 

 with the study of Moscow and its environs, for here many of the 

 geological stages which form the most important points of orienta- 

 tion in the study of south-eastern and middle Russia are well 

 developed and have been thoroughly investigated by numerous 

 geologists. 



In general terms Moscow is a city of very large area occupying 

 a number of hills from 400 to 500 ft. above the average water level, 

 which latter, at the southern boundary, is 348 ft. above the ocean. 

 The hills are cut out of the boulder clay and morainic sand, the 

 Cretacic, the Jura-Cretacic, (or Volgian), and the Jurassic down to 

 the middle Carbonic (or Muscovian), on which the latter rests ; by 

 the Moskowa, the Yaouza, the Neglinnaia and their little tributaries. 

 The lowest Mesozoic rocks overlying the Carbonic are of Middle 

 Callovian age, and in the eastern part, of the government of 

 Moscow they rest on the upper Carbonic rocks, chemically more 

 altered than the Muscovian which form " the rocky base on which 

 the ancient capital is built." [See Livret Guide, I.J, Borings 

 undertaken to find artesian water in the Devonic have revealed 

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