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■ SUMMARY
The Younger-Stampar eruption at
Reykjanes, SW-Iceland
In this paper, a 13th century fissure emption,
the Younger-Stampar emption in Reykjanes,
SW-Iceland, is described. The eraption is
characterised by effúsive activity on land and
explosive activity where the fissure met the
sea.
Reykjanes, forming the south-westemmost
tip of the Reykjanes peninsula, is situated
where the North Atlantic Ridge emerges from
sea and joins the Westem Volcanic Zone of
Iceland. Reykjanes is almost entirely covered
by Holocene lava-flows penetrated only by
small ridges of moberg (hyaloclastite) and pil-
low lavas, formed in late Pleistocene time. The
Holocene lavas, which all are of basaltic com-
position, were empted by small lava shields
and volcanic fissures. The fissure lavas repre-
sent the youngest volcanics in Reykjanes.
Volcanism on the Reykjanes peninsula is
confmed to five distinct, en echelon lying vol-
canic fissure systems. The Reykjanes volcanic
fissure system, the westemmost on the penin-
sula, is about 25 km long with its southem-
most 9 km in sea off Reykjanes. As a result,
fissure emptions in Reykjanes are character-
ised by both effúsive activity on land and
hydrovolcanic activity at sea where magma in-
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