Greinar (Vísindafélag Íslendinga) - 01.01.1935, Page 83

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Fig. 3.
The fossiliferous layer. The stick at the western part of the layer
is 90 cm. high.
organic materials; but to the east and further down it
becomes light coloured and its stratification for the most
part disappears. This part of the layer is mainly com-
posed of clay and contains few plant and insect remains.
It is my opinion that the eastern limit of the lake or
pond was at that point when the flow of lava occurred,
and this opinion is strengthened by closer investigation
of the plant and insect remains, and by the appearance
of the overlying doleritic lava. This doleritic layer is in
this place columnar and so compact in texture that it
is very reminiscent of ordinary basalt. Its appearance
indicates that it cooled rapidly, as would be the case if
it had flowed into water or over swampy ground.
I could not see my way to making more detailed re-
s,earch into the organic remains which are present, but
Prof. Knud Jessen of Copenhagen has done me the fa-
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