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has been fixed by Amdrup, basalt is everywhere predominant; 

 to the west it appears as far as the "South Glacier" (Syd 

 Bræi, directly S. of Danmark I., after which its substratum, 

 gneiss, rises higher and higher. Around the whole of Gaase 

 Fjord, however, according to Bay, this rock is covered by 

 basalt. More detailed observations as to the course of the 

 boundary line between these two rocks do not seem to have 

 been taken, and yet an investigation 'into the matter in this 

 area, where the boundary for stretches of many miles lies ex- 

 posed, would be extremely valuable and might contribute to the 

 solution of a number of important questions of geological and 

 early topographical interest. Dikes may also occur at greater 

 distances from the true basaltic mass, thus, for instance, 

 occasional ones on Liverpool Land and on Jameson Land, in 

 the N. part of which we even find basaltic rocks in large 

 masses and of different appearance (see below), while the most 

 northerly dikes I saw were at С Fletcher and could be looked 

 upon just as well as belonging to the N. area as to the one 

 in question^). Whether the sheets of porphyrites from Fame 

 J. and Fleming Inlet can really be classed among this series, 

 is a question that cannot be answered at the moment. In the 

 W. dikes, still from the innermost part of West Fjord, have 

 been described by Bay, in the NW. dikes from the NE. part 

 of Milnes Land, but not from North-West Fjord. In the South, 

 Amdrup has described similar conditions: basalt as a covering, 

 and at the contact an Archaean rock, interspersed with ex- 

 ceedingly numerous basalt dikes ^'). As to the presence of basaltic 



') The S. part of the N. basalt area is moreover little known, and it looks 

 as If certain divergences from the usual types should occur here, so 

 for instance at С Broer Rays, described by Toula and Nathorst. 



*) An excellent idea of the great contrast between the Archæan rocks, 

 rounded by the erosion by water and ice, and tlie steep and rugged 

 basalt clifFs, is civen by figures 4 and 5, reproduced from photographs 

 taken by Amdrup not far from one another, near the southern boundary 

 between the two formations. 



