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[ 529 ] 

 LIX. Proceedings of Learned Societies. 



GEOLOGICAL SOCIETY. 



[Continued from p. 176.] 



June 27th, 1906.— Sir Archibald Geikie, D.C.L., Sc.D., 

 Sec.R.S., President, in the Chair. 



HE following communications were read: — 



1. ' Interference-Phenomena in the Alps.' Bv Mrs. ^laria 

 M. Ogilvie Gordon, D.Sc, Ph.D., F.L.S. 



In former papers * the authoress pointed out that, while the leading 

 axis of the Alpine mountain-system extended in an east-and-west 

 direction, and it was generally accepted by Alpine geologists that 

 Alpine areas had endured horizontal compressive stresses in a 

 north-and-south direction, her own studies of Alpine geology 

 had led her to the conclusion that there had also been cross- 

 deformation throughout the whole region, including both plicational 

 and overthrust-effects ; and that this cross-deformation had been 

 induced in relation to horizontal pressures which had acted from the 

 Hungarian Basin westward over Alpine areas. In a quite similar 

 way, radially-directed horizontal pressures had acted round the 

 northern, eastern, and southern periphery of the Hungarian Basin, 

 and had originated the deformational systems of the Carpathian 

 Mountains. 



On the Alpine side of the Hungarian Basin, owing to the resisting 

 character of the previously-plicated rocks composing the Palaeozoic 

 Alpine chain, the ancient chain had been broken up by the east-and- 

 west compression into a series of cross-segments or fault-blocks, and 

 there had been a general westward crush of the series. The leading 

 cross-segments named by the authoress were — (1) the Western Alps, 

 (2) the Engadine, and (3) the Styrian Alps. 1 ( - ) Overthrust-effects 

 had been produced not only at the western margins of the segments, 

 but also in some cases at the eastern margins, e.g. notably in the 

 Western Alps, and at the Judicarian Fault in the Eastern Alps. 

 Further, these same cross-segments in the Central Alps had been 

 from their first initiation, interrupted on the north and south by 

 ancient leading east-and-west faults, in relation to which sagging or 

 downthrow-movements took place towards the Central Alpine band, 

 and overthrust-movements occurred in opposite directions. 



The present paper, so far as it deals with the general structure of 



* M. M. Ogilvie Gordon, (1) 'Torsion-Structure in the Alps' Xature, 

 Sept. 7th, 1899, vol. lx, pp. 443-46; (2) ' The Crust-Basins of Southern Europe ' 

 Seventh International Geographical Congress, Berlin, 1899 (Proceedings of 

 the Congress, Part II, pp. 167-80 & pi. vii) ; and (3) 'The Origin of Land- 

 Forms through Crust-Torsion ' Geogr. Journ. roL xvi (1900) pp. 457-69. 



Phil. Mag. S. 6. Vol. 12. No. 71. Nov. 1906. 2 M 



