part 4] SCANDINAVIAN ' MOUNTAIN PROBLEM.' 399 



To illustrate the conditions in the southern part of the Sparag- 

 niite area (a district situated outside the typical overthrust regions 

 of Tornebohm) I have drawn the sections shown in fig. 5 (p. 400), 

 reaching from the Randsfjord (seeR in fig. 1) and northwards for 

 a distance of about 60 kilometres (say, 37 miles). 



Primarily there occurred in the northern part of this district, at 

 a time immediately preceding the deposition of the Lower Cambrian 

 Holmia {Olenellus) Shale (which, according to our present know- 

 ledge of the Cambrian System of the Cordilleran region of North 

 America, took place some way up in what is now known to be the 

 Cambrian Period), a sedimentation of sandstones (Sp. in the 

 upper section), while on the south some denudation must still 

 have taken place. Moreover, the Holmia Shale was deposited 

 only in the north. After a thick series of younger, fossiliferous 

 Cambro-Silurian (C-S) had been deposited throughout the whole 

 region, an inclination of the pre-Cambrian floor took place in 

 late Silurian time. Through pressure from the north thrusting 

 began, and originated a typical imbricate structure as shown 

 in the three lower drawings, the lowest of which represents the 

 actual conditions as now observed. We note thick masses of highly- 

 deformed sandstone (mostly quartzite) above the basal remnants 

 of the fossiliferous Cambro-Silurian Series. These remnants 

 mainly consist of highly-fractured Middle Cambrian alum-shales 

 in which are found species of Agnosias, Paradoxides, etc. 1 

 Passing northwards, we observe above the quartzites the grey-green 

 Holmia Shale, overlain in turn by the Middle and Upper Cambrian 

 alum-shales, and finally by Ordovician strata. 



Conditions similar to those observed by me in the Randsfjord 

 district were previously described from a more easterly district of 

 the Sparagmite area in Norway by O. E. Schiotz. 2 



As has already been mentioned, in Southern Norway, for 

 instance, in the eastern part of the Jotunheimen district, a younger, 

 post- Cambrian ' Sparagmite ' series exists, which unconformably 

 overlies Ordovician phyllites. This series commonly contains con- 

 glomerates, which have recently been studied by V. M. Gloldschmidt, 3 

 who has found much of interest concerning them. In one district 

 the material in the boulders consists to a great extent of a gabbro 

 of the same kind as that seen in a gabbro-mass that overlies the 

 conglomerate. According to Golclschmidt, the material of the 

 conglomerate was originally derived from this gabbro-mass 

 deposited on the south side of it; then, through pressure from the 

 north, the (rest of the) gabbro was thrust over the conglomerate, 

 and covered it. The present conditions are illustrated in the two 

 lower sections in fig. 5, p. 400 (Grb=gabbro, Cgl = conglomerate). 

 In another district a quartz-conglomerate occurs in a similar 

 relation to a mass of granite. 



It is evident that, from this point of view, the above-mentioned 



1 Norges Geol. Undersok. No. 75, 1915. 



2 Ibid. No. 35, 1903. 

 :t Ibid. No. 77, 1916. 



