20 Prof. A. K Nordenshiold — Geology of Spitzhergen. 



II. Hecla Hooh Strata.^ — We have not had the good fortune to 

 find in Spitzhergen any strata containing Silurian fossils. But it is 

 probahle that the Silurian forniation of Scandinavia is correlated to 

 the immense succession of strata occurring here, which I, in the 

 absence of any other name, have called after the mountain (Hecla Hook 

 on Treurenberg Bay) where they have their greatest development. 

 These strata, which besides occupy an immense area in Spitzhergen, 

 consist, without taking into account inconsiderable variations, of 



1. Lowermost, grey compact dolomite intersected by white veins of quartz and 

 calcite. It was taken at first for grey limestone before it was analyzed by Gr, Lind- 

 strom,^ wbo found it to consist of grey dolomite from English Bay : 



Carbonate of lime 53'98 



Carbonate of magnesia , 44'69 



Carbonate of protoxide of iron 0-18 



Incombustible residue insoluble in acids 1-39 



Chlorifle , „ trace 



2. Black clay-slate. 100-24 



3. Hard whitish grey or red quartzite. 



4. Black clay-slate, at certain places passing oyer to a breccia-like mixture of 

 pieces of clay-slate and a hard sandstone containing lime. 



5. Grey dolomite, like 1. 



The Hecla Hook strata (quartzite and white-veined dolomite) occur 

 in the part of Spitzbergen now referred to, in the rocks at the mouths 

 of the fiords, along the outer coast between the fiords, and upon the 

 islands and rocks by which the outer coast is environed ; for example, 

 dolomite with veins of limestone on the western side of Safe Haven, 

 quartzite at the Alkhorn, upon the outer archipelago between Ice and 

 Bell Sounds, and forming the rocks on the shores of the neighbouring 

 coast in St. John's Bay, on the southern point of Charles Foreland, 

 etc. To this probably also belongs the Clay- slate breccia, which im- 

 mediately underlies the Tertiary strata at Cape Lyell. 



The strata which belong to this group are most frequently raised 

 up vertically, having their direction principally from north to south. 

 It is exceedingly remarkable that we have not happened to find ia 

 them any fossils, though diligently examining series of strata thou- 

 sands of feet in thickness, and although the Hecla Hook slate, on 

 account of its fineness and the absence of pyrites, seems specially 

 adapted to preserve the organisms which were imbedded in it.^ 

 Probably this series of strata are an extensive fresh- water formation 

 from the same period of time as that during which the Silurian 

 strata were deposited in Scandinavia. 



III. Liefde Bay Strata (probably forming the boundary between the 

 Carboniferous and the Devonian formations). — The above-mentioned 

 quartzite is overlain in Lomme Bay by slate, limestone, sandstone 



^ Since the publication of my Sketch of the Geology of Spitzbergen, I have had 

 the good fortune to find fossils in the red schists at Liefde Bay. These strata, which 

 I formerly .correlated with the Hecla Hook formation, I have now accordingly re- 

 ferred to a separate division, " the Liefde Bay Strata." 



2 G. Lindstrom, Analyses of Eocks from Spitzbergen, Ofversigt af Vet.-Akad. 

 Forh. 1867, Ko. 10. 



3 Yet some indistinct and undetermined bivalves and inconsiderable graptolite-like 

 impressions occur at the outer shore of Grey Hook in a black slate, which probably 

 belongs to No. 4 of the Hecla Hook strata. 



