Jökull - 01.01.2005, Blaðsíða 34

Árni Hjartarson
Figure 1. A simplified geological map of the Tinná Central Volcano. The domain of the volcano includes all the
acid and intermediate lavas related to it. The approximate limits of the Skati Dome and the proposed alignment
of the caldera are indicated. – Einfaldað jarðfræðikort af Tinnáreldstöðinni. Óðal hennar er afmarkað með
brotalínu og innan hennar eru öll súr og ísúr hraun sem frá henni eru ættuð. Áætlaðar útlínur Skatagúlsins eru
sýndar með heildreginni línu svo og lega öskjubrots.
aration because the young strata pile in the upper-
most part of the mountains hides their interconnec-
tion. Torfufell has never been mapped or investigated
with any accuracy. It is in the strike east of the Tinná
Central Volcano and of similar age. Hjartarson et al.
(1998) suggested it belonged to the Tinná Central Vol-
cano. Jóhannesson and Sæmundsson (1998), on the
other hand, interpret them as two individual central
volcanoes on their geological map of Iceland. This
controversy will be left for later investigations.
Research history
Geological research in the Skagafjörður Valleys be-
gan in the 18th century (Ólafsson 1943, Pálsson
1983). The first observations concentrated on the lig-
nite seams that were known in several places in the
area; later investigations have revealed that these all
belong to a sedimentary layer associated with the cen-
tral volcano. In those days a great deal of attention
was given to the lignite, in spite of its poor quality, be-
cause many people believed it might indicate valuable
34 JÖKULL No. 55