Out of the Blue
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Harald Drever and the geology of Greenland
Harald Irvine Drever was a lecturer in Geology at the University of St Andrews,
1938-1975. On a brief visit to Ubekendt Ejland (Unknown Island) in West Greenland
he discovered unusual volcanic rocks, rich in the mineral Olivine. He returned to the
area several times and collected many specimens, some of which are displayed here.
These igneous rocks originated as part of the Earth's mantle which became molten
magma when the North American continental crustal plate split away from Europe
60 million years ago, creating the Atlantic Ocean.
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Petrified Tree in Basalt Lava from Ubekendt Ejland
This tree grew in ashy soil near a volcano some 50 million years ago,
before being interred under a basalt lava flow. The wood has been
replaced by minerals - yellowish knobbly chalcedony and white
crystalline calcite.
At this time the North Atlantic was a small ocean, gradually widening
as the North American continent drifted away from Europe.
F1001 (732), University of St Andrews Museum Collections
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Olivine-rich basalt (Picrite) with clear gem olivine crystals
(peridots), from Ubekendt Ejland
Drever was eager to study these rocks to investigate the crystallisation
of basaltic magma. This specimen comes from the bottom of a sheet of
magma intruded into the crust. The green olivine crystals probably settled
at the base of the sheet due to their high density after crystallising from
the magma soon after it was emplaced. These crystals weather out of the
rock and are concentrated on the beaches by the waves and tides. Local
villagers collect large ones for use in jewellery.
Un-numbered specimen, University of St Andrews Museum Collections
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Basalt from Ubekendt Ejland
Basalts are generally dark, minutely crystalline rocks and can appear dull
and uninteresting at first sight. When viewed with a polarising microscope,
the various minerals display a diverse range of colours according to their
chemical composition. The olivines show especially strong, bright colours
as shown in the photomicrographs below.
MV37, University of St Andrews Museum Collections
Photomicrograph of Terrestrial basalt
DRSB 400, University of St Andrews Geology Department
Photomicrograph of Terrestrial basalt
DRSB 401, University of St Andrews Geology Department
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From Greenland to the Moon
In 1971 the Apollo 12 Lunar Mission returned with very similar olivine
rich rocks from the moon and NASA invited Drever to join their research
team studying them. Returning to Ubekendt the following year he found
the local villagers were fairly indifferent to their region's geological
importance: "That their village shared some of its substance with the moon
the villagers were happy to learn, but exhibited no evidence of surprise."
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Photomicrograph of lunar basalt
DRLP 526, University of St Andrews Geology Department
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This view shows igneous rocks that so interested Drever on Ubekendt.
The dog is standing inside the skull of a whale.
DRGB 002, University of St Andrews Geology Department
Dundee University continues its links with the Antarctic with
its part in the development of a new museum on South Georgia.
Click here to find out more.
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