TRANSLATIONS AND NOTICES 



OF 



GEOLOGICAL MEMOIRS. 



On the Geology and Sxjreace-featuees of Trai^-sylvania. 

 By Dr. Stache. 



[Proceed. Imp. G-eol. Instit. Vienna, March 12, 1861.] 



Four great geological groups of strata, each witli characteristic oro- 

 graphical and physiognomical features, may be distinguished within 

 the province, striking even the superficial observer. The central 

 portion, once the bottom of a marine basin, now filled up with the 

 marly and arenaceous deposits of the late Tertiary period, and in many 

 places impregnated with salt, presents fertile valleys and slopes, 

 together with barren ranges of hills and high precipices, intersected 

 in every direction by considerable rivers and a number of rivulets., 

 Around this central basin runs a zone of Eocene hills (marly and 

 calcareous strata with abundance of limestone and gypsum), con- 

 spicuous by their sharper outlines and by their groves of oaks and 

 beeches. This zone is, as it were, the precursor of the third zone, 

 marking the natural and political frontiers of the province by a waU 

 of crystalline rocks with extensive, and partly as j^et untouched, 

 forests of pine and beech. The fourth or trachytic group, important 

 on account of its metalliferous deposits, occurs in the eastern part of 

 the province, in the shape of hilly massifs, and in dispersed and 

 isolated patches in the western portion. 



The crystalline massif on the western frontier, between Transyl- 

 vania and Hungary, has the general form of a square, protruding 

 far into the interior. The main range, running S. to N., between the 

 water-courses of Szamos and Aranryos on one, and the Koras on 

 the other side, has an average altitude of 4500 feet. Three lateral 

 ranges, of from 3000 to 5000 feet elevation, are detached from the 

 main range, advancing eastward into the Eocene territory. The 

 valleys and gullies in them, steep and deep (1000 to 1500 feet in 

 the Bakato Yalley), more resemble crevices than valleys. 



The basis of the main S.-IST. range is crystalline rocks, overlain 

 with the red slates, grey and reddish quartz-sandstones, and white 

 or spotted quartz-breccia (" Yerrucano") of the Lower Trias. The 

 tops and longitudinal crests consist of well- stratified blackish or 

 grey limestones of the Upper Trias, assuming on the surface a re- 

 semblance to the Istrian " Karst Limestone" wherever they are not 



VOL. XVIII. PART II. c 



