I92I. No. 8. ox THE ECLOGUES OF NORWAY. 23 



Many local mineral developments within olivine-rock masses also bear 

 evidence of conditions under which hydrated minerals were formed. To 

 this group of phenomena belongs the alteration of the eclogitic nodules in 

 the olivine-rock into chlorite, talc, and epidote. Lumps and lenses 

 or veins of talc are common, and a.ssociated with this mineral occur 

 chlorite, b i o t i t e-1 i k e mica and carbonates. 



At other places the amphibolite faciès has locally developed in the 

 form of either cummingtonite or anthophyllite. H.Reusch recently described 

 an occurrence of anthophyllite-asbestos near Berget in Almklovdalen '. The 

 anthophyllite occurs there in the form of a dike in the olivine-rock. 



Other o c c u 1- ]■ e n c e s of o 1 i \- i n e - r o c k in N o r d f j o r d and 

 Mere. In the numerous other occurrences of dunite and saxonite in the 

 area considered the petrographical characters of the rocks are nearly 

 identical with those in Almklovdalen, though such a perfect degree of pre- 

 servation is rare. 01i\ine-rock free from garnet or pyroxene is probably 

 most common, but saxonites containing much enstatite are also wideh- 

 distributed. 



Saxonite with dominant enstatite has been met with at So r pol in 

 Sel je (Reusch) and west of Saude near Larsnes, Gursko (Eskola). 

 Enstatite and oli\ine almost equal in amount are met with in the rock of 

 Hovden in Hornindal, Nordfjord (ReuschI (with cummingtonite) and 

 in Sol vbergkn ausen near S tens vi k, Sondmore (Eskola). 



Pvrope-diopside-olivine rock has, except for the occurrences in Alm- 

 klovdalen, only been recorded by J. H. L. Vogt (loc. cit. 1883) from the 

 \icinity of the occurrences of eclogite near Ta fjord, Nord alen, Sond- 

 m ore. 



The Labradorite-rock. 



The labradorite-rock occurs, in the gneiss-area, much in the manner 

 of other light bands in the gneiss, but the bands of this rock, homogeneous 

 in composition and structure, may attain much greater breadth than the 

 light gneiss bands. I have found bands of labradorite-rock but a few meters 

 thick, and the largest observed measure a few hundred meters. 



At the boundaries they pro\e to be younger than the gneiss, enclos- 

 ing fragments and intruding into the gneiss as veins almost parallel to 

 the strike. 



Labradorite-rock has so far only been met with in tracts wliere olivine- 

 rock and eclogite occur, and in most cases the connection between these 

 three kinds of rocks is strikingly close. These relations will be discussed 

 in the chapter dealing with the eclogites. 



Labradorite-rock from the mountains east of Ekremsaeter 

 in Almklovdalen. This occurrence aflfords an example of labradorite- 



' H.Reusch, En asbesttorekomst i Vanslven. Norsk Geologisk Tidsskrift V, 19 18, p- 95. 



