Rit (Vísindafélag Íslendinga) - 01.07.1962, Page 176

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character of the flora, already rather early. As “cool” or at
least poor flora is sometimes older than a “warm” or rich
flora, there is no monotonous change, and the flora cannot
be used for detailed stratigraphy.
Best insight into the conditions is gained in Eastem Ice-
land. In the fjords regions we have here a 5—6 km thick
pile whose lowest horizon (Gerpir) is considered by Pflug
to be of Lowest Tertiary, perhaps even Uppermost Cretace-
ous. Near the top of this pile, in which Walker has not been
able to discover any unconformity, and only thin sediments,
are the lignite seams of Hólmatindur and Tungufell. The
former seem to belong to the Lower Tertiary on palynological
grounds (Schwarzbach, private communication), while the
views expressed on Tungufell are widely divergent, as we
shall consider below.
Farther inland we have higher members of the Plateau
Basalts which form a thick group with lignites of much cooler
character than that of Gerpir. This group dips up to 10° NW
and has been subjected to peneplanation.
Bather high in this group the locality Bessastaðaá has a
flora comparable with the warmest zone of the Tjörnes sedi-
ments (Pflug 1959, p. 167). In the close neighbourhood, and
nearly certainly a little lower than Bessastaðaá, is the loca-
lity Hengifossá with a flora of a much cooler character. Pflug
interprets it as a cold time at the beginning of or at the end
of a glacial time.
A number of localities at Jökuldalur and Vopnafjörður
which belong to this group of basalts have a flora compar-
able with Bessastaðaá, but the content is horizontally quite
variable in this area (Jux 1960). Pflug and Jux and much
earlier Windisch (1886) place this flora into the Upper Ter-
tiary or even Upper Pliocene.
We now come back to Tungufell. According to the map-
ping by Walker (1959) in this area this locality should be
close to the Hólmatindur lignite and we must expect this to
lie far below the mentioned inland basalt group. My recon-