1896.] GEOL. IAGTTAGELSER I TELEMARKEN 0. S. V. 99 



A short summary of the contents. 



Geological notes from Telemark, Inner-Hardanger, Numedal 



and Hallingdal. 



Ihe present paper contains geological observations made 

 for the Geological Survey of Norway in the central regions of 

 the southern part of the country. 



The Thelemarken district lies to the West from Kristiania. 

 We find here over a wide area a division of the Archæan, which 

 contains true clastic rocks, conglomerate, sandstone and phyllite and 

 besides these rocks others of uncertain origin, gneissic rocks, horn- 

 blende schists, „hornstones partly of a porphyric appearance" etc. 

 This complex, which is often spoken of as the Telemark-forma- 

 tion and is to be compared with the American Algonkian, is 

 surrounded with gneiss and gneiss-granite. Dahll regarded these 

 as undoubted eruptives, but the relations are not yet sufficiently 

 studied. — Kjerulf has on his maps some spots of porphyritic 

 rocks with the same designation as his postsilurian eruptives. 

 The present! author has found these rocks to belong to the 

 Thelemark formation and show traces of pressure. — The 

 first figure on p. 13 shows irregular lenses of quartz with some 

 asbestus (vertically streaked). The encasing rock is diorite. The 

 second^figure represents the spot x on a larger scale. Pag. 14 

 we se a whetstone-quarry. The rock is quartz-rock with double 



