77 
Sænkninger. Om den sidste Sænkning lier kar været samtidig 
med Purpurasænkningen ved Hunafloi, er ikke muligt at afgøre, før 
paagældende Dannelser er nærmere undersøgte. 
I Purpuraaflejringerne ved Hunafloi har man det først frem¬ 
førte Bevis for, at Havet i et Afsnit af den postglaciale Tid har 
været lidt varmere ved Island end i Nutiden. I Aaret 1906 op¬ 
dagede Dr. Helgi Pjeturss Skalaflejringer ved BreiOamerkurjøkull 
i Syd-Island, der peger i samme Retning, og desuden tyder paa 
mindre Udbredelse af Jøkelen i den Tid, da disse skalførende Lag 
afsattes 1 ). Formentlig er disse Dannelser samtidige med Purpura- 
lagene. For Tiden foreligger ikke andre sikkre Iagttagelser i denne 
Retning i Island. 
Summary. 
1. A the end of the Glacial Period a subsidence of the land 
takes place at the S.W. coast of Hunafloi in North-Iceland; the 
sea rises to a level of at least 4 0 — 5 0 meters high er than 
the present one. Next foliows reelevation of the land, the sea 
gradually retreats till the coast line is on a level at least c. 2 
meters lower than it is at present. 
During this period glacial deposits (till and compact ground 
morains) on the submerged coast are covered by great layers of 
fine laminated clay, probably deposited by glacial torrents, wkich 
are again covered witk another deposit of gravel and sand. In 
this way mighty terraces are built up in the fiords and in the 
valleys, where the sea is most quiet and the torrents deposit most 
material; but at the mouths of the fiords, where the surf is stron- 
gest, the sea at the same time forms rock-shelves and broad erosion- 
terraces, which are best developed in a height of 40—50 meters. 
x ) Dr. H. P jet ursson: Einige Ergebnisse seiner Reise in Sud-Island 
im Sommer 1906. — Zeitsckrift der Gesellschaft ftir Erdkunde. Pag. 
606—609. Berlin 1907. 
