Jökull - 01.12.1983, Page 22

Fig. 1. Icelandic Types of Basalt Volcanoes (Modified from Thorarinsson, 1959 and 1968; and from
Thorarinsson and Saemundsson, 1980).
NATURE OF ENVIRONMENT FORM OF FEEDER CONDUIT
VONCANIC ACTIVITY DURING FORMATION SHORT FISSURE OR TUBULAR CONDUIT LONG FISSURE
EFFUSIVE ACTIVITY — Landforms Subareial LAVA RING Type: Eldborg (Hnappadalssýsla) -
resuldng from ílowing material LAVA SHIELD Type: Skjaldbreidur LAVA SHIELD ROW Type: Thjófahraun
MIXED ACTIVITY Subglacial/ subaerial TABLE MOUNTAIN (STAPI) Type: Herdubreid SUBGLACIAL RIDGE Type: Kálfsdndar
Landforms resulting from flowing material and Submarine/ Subaerial TABLE MOUNTAIN (STAPI) Type: Surtsey —
Submarine SEAMOUNT Type: Jólnir SUBMARINE RIDGE Type: Eldeyjarbodi
hyaloclastites Subglacial * Type: Keilir * Type: Fögrufjöll
Landforms resulting from flowing and airborne material SPATTER CONE Type: Búrfell (Hafnaríjördur) SPATTER CONE ROW Types: Threngslaborgir
Subaerial SCORIA CONE Type: Búdaklettur SCORIA COEN ROW Type: Vikraborgir
— MIXED CONE ROW Type: Lakagígar
EXPLOSIVE (OR PHREATO- MAGMATIC) ACTIVITY Landforms resulting from airborne material TEPHRA RING Type: Hveríjall TEPHRA RING ROW Type: Vatnaöldur
Subaerial MAAR Type: Graenavatn MAAR ROW Type: Valagjá
* These two landforms, Keilir and Fögruíjöll, for which no names are available in English, are the
subglacial counterparts to a single subaerial cone and a mixed cone row, respecdvely.
1929) and Rittman’s two classification schemes
for „Zentral-Vulkane" and „Linear-Vulkane“
(1936), offered the first comprehensive classifica-
tion system for the volcanoes of Iceland. In 1959
(and 1960), he published the first complete
classification of the 13 main types of Icelandic
volcanoes. In 1968, he published a minor modifica-
tion of his earlier classification scheme. Both land-
form classifications were based on the relationship
of the type of eruptive products (lava, lava and
tephra, or tephra), number of eruptions (one or
more than one), and the form of the eruptive vent
20 JÖKULL 33. ÁR