Jökull - 01.01.2005, Page 147

Society report
George P.L. Walker and his geological research in Iceland
Leó Kristjánsson
Institute of Earth Sciences, University of Iceland, Askja, Sturlugata 7, IS-101 Reykjavík, Iceland leo@raunvis.hi.is
INTRODUCTION
The following brief obituary notice was presented
at a meeting of the Societas Scientiarum Islandica
(Vísindafélag Íslendinga) on 23 Feb 2005: “George
Patrick Leonard Walker who was born 2 March 1926,
grew up in London and Northern Ireland, and stud-
ied Geology at Queen’s University, Belfast. He com-
pleted a Ph.D. at the University of Leeds in 1955.
His thesis topic concerned the Early Tertiary igneous
rocks of Northern Ireland, in particular their hy-
drothermal alteration minerals. He became Assistant
Lecturer at Imperial College in 1951, Lecturer in 1954
and Reader in 1964.
In the summer of 1954 Walker visited Iceland and
was impressed by the lava pile of its Eastern fjords.
In the following summer he began his research on
the strata in that region, and returned to Iceland every
field season through 1965. Walker was really the first
geologist to carry out simultaneous systematic map-
ping, in three dimensions, of many aspects of geol-
ogy in Iceland. Previous research by Icelandic and
foreign geologists had mostly either been directed at
surface formations or at particular phenomena such
as tephra deposits, fossils, glacial formations, or in-
dividual active volcanoes. In the early 1950’s, others
had initiated stratigraphic mapping e.g. with the aid
of magnetic polarities in the lava pile of Iceland, but
Walker introduced new methods which turned out to
be very successful. His work was most thorough and
accurate, and he revolutionized all thinking about the
geological structure and genesis of Iceland. This ap-
plied not only to the inactive regions he was studying,
but also to the younger active ones and the geother-
mal processes taking place there. Walker thus turned
on its head the old saying of Geology: “The present is
the key to the past”.
The best known publications by Walker on Ice-
land include those on the geology of Reyðarfjörður
in 1959, on zeolites in 1960, and on the Breiðdalur
central volcano in 1963. In the paper on zeolites he
touched on other topics such as the buildup of the
lava pile, and the emplacement of intrusions in the
volcanic zone accompanied by spreading and sub-
sidence. He demonstrated that the geological his-
tory of Iceland was a continuous and indeed almost
a steady-state process, rather than consisting of a few
major episodes of different volcanic or tectonic up-
heavals as previously envisaged. Walker developed
this view further in subsequent papers, including one
with Gunnar Böðvarsson in 1964.
In addition to Walker himself, several of his
graduate students carried out their field studies here,
mostly in Eastern and Southeastern Iceland, and he
also took part in collaborative projects based on his
mapping. Of the numerous papers resulting from
these efforts, three were published by the Societas
Scientiarum Islandica.
Around 1965 Walker began research on the prod-
ucts of explosive volcanic eruptions worldwide, and
he has stated that the Surtsey eruption contributed to
his interest in these. This field of research brought
him much recognition, just like his previous work on
Iceland. Although his trips to Iceland became only
intermittent after 1965, he kept writing important pa-
pers that were directly or indirectly connected with
the geology of this country. In 1978 Walker accepted
a research position in New Zealand for three years; he
then moved to the University of Hawaii as Professor
and investigated volcanoes in the Pacific region. He
returned to England upon retiring in 1996.
Walker became a corresponding member of the
Societas Scientiarum Islandica in 1968, he was
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