Skaergaard history


In its Danish spelling, Skærgård, is the official name of the area. Skaergaard, the internationalised version, is a geological formation name, referring to the intrusion itself. Skærgård is a Scandinavian word for a rocky coastline protected by numerous off-lying islands  and skerries, where the sea merges with the land via an anastamosing system of fjord-like channels. Such coastlines are common around Scandinavia, especially along the Swedish and Finnish Baltic coasts, and by comparison that at Kangerlussuaq is very modest, covering only a tiny area.  The name was applied however by the members of the Amdrup-Hartz Expedition in 1900 (Amdrup, 1902), who travelled the approximately 800 kilometres from near the present day Scoresby Sund (Ittoqqortoormiit) southwards to Ammassalik (Tasiilaq) in an open rowing boat and who were, so far as is known, the first Europeans to visit the area. To these travellers, after rowing 400 kilometres through drifting polar pack ice along the black, inhospitable basalt cliffs of the Blosseville Kyst (=  Coast), Skærgård with its numerous small, rounded islands of warm brown (Fe-rich) gabbro and pale Archaean country rock gneisses, the large open fjord of Kangerlusuaq, must have seemed like a new land.

"Skærgård" does not appear to be used by the local Eskimo or Inuit people who live semi-permanently in the area. Instead, it is referred to as Kangerlussuaq (Kangerdlugssuaq in the earlier orthography, used in the geological literature), which means "Big Fjord", a name which occurs very frequently throughout Greenland (e.g. Søndre Strømfjord, the main traffic centre and former US. military air base on the West coast, is also Kangerlussuaq).

[Place names of the Kangerlussuaq area]

History of indigenous settlement

Needle container from a woman's grave in Kangerlussuaq (Mathiassen 1935)These Europeans - of the Amdrup-Hartz expedition, or even unknown European whalers who may have landed here earlier without leaving a record - were by no means the first people in this area. Indeed, Kangerlussuaq was a milepost for the Amdrup-Hartz Expedition because it marked the northernmost point known to the Ammassalik people (Ammassalimiut) as told to their discoverer Gustav Holm in 1882 (Gustav Holm, 1888, 1889). Although no people lived in the area at the turn of the century, numerous ruins of earlier dwellings testify to the previous presence of the Inuit people. Indeed, an old man, Kunak, told Gustav Holm that he had been born on the nearby island of Nordre Aputitêq ( - new spelling: Apulileeq) and had travelled to Kangerlussuaq in his youth. Material returned by the Amdrup-Hartz Expedition was described by W. Thalbitzer (1909, see also Thalbitzer, 1914) and excavations on the house ruins at Skærgård and in Miki Fjord where made by the Scoresby Sound Committee's 2nd East Greenland Expedition in 1932 (Mathiassen, 1934; Degerbøl, 1934) and the Anglo-Danish East Greenland Expedition of 1935 (Larsen, 1938). Since 1935 only minor archaeological work has been carried out, in spite of the fact that revolutionary changes have taken place in the field of Eskimo archaeology.

The reason for the extinction of the Inuit people shortly prior to the arrival of Europeans is unclear but must be related to the general depopulation of the entire East Greenland area during the last century. Authorities have been divided on whether the population came to Kangerlussuaq from the north or the south but all agreed that their dwellings date from the period around the late 13th century to the early 19th century. Degerbøl (1934) recognized three types of ruin: a sunken type with rounded corners and a short entrance passage; a longhouse similar to those of Ammassalik but otherwise unknown further northwards and small houses built within the earlier longhouses and featuring long entrance passages. Since the 1930s, Eskimo archaeology has advanced considerably and we now know that the settlement of Greenland had begun more than 4000 years ago by the so-called "Palaeo-eskimos". Some objects in the earlier collections from Kangerlussuaq are of undoubted Palaeo-eskimo origin (Kapel, 1990) and new investigations are now required in the light of greatly improved archaeological techniques and vastly extended knowledge - the Palaeo-eskimos were unknown at the time of the earlier excavations. During a reconnaissance in connection with the projected gold mine it was found that some of the sites had been vandalized, although many are still untouched either by vandals or archaeologists - a further argument for renewed archaeological work.

Mikis Fjord in the early 1930ies (Mikkelsen,1934)To the Ammassalik people, Kangerlussuaq apparently has always been regarded as an especially rich hunting ground - a kind of Shangri-La, that can be reached only with difficulty but where life can be expected to be good. At the time of Gustav Holm, an umiak  or family boat left Ammassalik for Kangerlussuaq, but was never heard of again, and this expedition was probably the origin of the corpses found in the house at Nugalik or Dødemandspynten (="Dead Man's Point"), about 100 km to the south, found by Amdrup some 30 years later (Amdrup, 1902). The Scoresby Sound Committee's 2nd East Greenland Expedition was largely motivated by the expressed desire of the Ammassalik people to colonize Kangerlussuaq. Ammassalik people still regard the area with high esteem: some as pragmatists who realize that they can apply their hunting skills here with the prospect of improving their income, others as idealists who see the area as a retreat from the white man's world to the ways of their forefathers, untrammelled by money, stores, officials, drunkenness and the like.

In 1947, twenty five people from Ammassalik moved to Kangerlussuaq, but found the hunting poor and were forced to return. According to Underbjerg (1984) this was possibly because the weather station was located on Skærgårdhalvø at this time and he speculates that perhaps one of the reasons for moving it to Nordre Aputitêq was to improve the hunting conditions around Skærgård.

View from Skaergaard across the mouth of Kangerlussuaq (Mikkelsen 1934)Recent endeavours to colonize Kangerlussuaq date from 1966 when a number of families from Ammassalik (Tasiilaq) overwintered in the remains of the old American weather station and the expedition houses from the 30s. They had a very good season (- 35 bears, 62 narwhales and about 2100 seals) and returned most years afterwards. Not surprisingly, many from Ammassalik find life at Kangerlussuaq difficult and yearn for home, but others return year after year. An excellent study of present social conditions among the Ammassalimiut has been presented by Robert-Lamblin (1986), who recorded the numbers of hunters at various sites along the coast up to 1979. In recent years the number of people living at Kangerlussuaq was: 56(20) in 1986-87 (after a hiatus of three years), 94(37) in 1987-88, 39 (16) in 1988-89, 0 in 1989-90 and 18(9) in 1990-91. In each case the first number is the total number of individuals and the second (in brackets) the number of children under 16 years. Figures are based on data from Tasiilaq local council.

The 1930s and 1940s

Wager discovered the Skaergaard Intrusion during a brief foray by ship during the British Arctic Air Route Expedition (BAARE) in 1930. This expedition overwintered at Supertooq, which is just west of Sermilik Fjord in the Ammassalik District. It was notable in that it made use of some of the first aircraft to be employed in Greenland: two De Havilland "Gypsy Moths". Thus oblique aerial photographs of high quality were available for field work, and examples were published in the Skaergaard Memoir (Wager & Deer, 1939) and subsequent works. Unfortunately, the negatives are no longer serviceable due to poor storage conditions. The BAARE expedition was described in the book Northern Lights  by F. Spencer Chapman (Chapman, 1932) while an official report appeared in the Geographical Journal (Watkins, 1932a & b) to which Wager contributed a geological summary (see also Watkins, 1932c).

Skaergaard as it was - skin tent with young Greenlanders during the Wager and Deer expedition of 1935-36.Wager's first visit to Skaergaard was of necessity brief, but he returned in 1932 as a member of the Scoresby Sound Committee's 2nd East Greenland Expedition in 1932 (Mikkelsen,1933a & b). This committee had been formed to promote the establishment of a settlement at Scoresby Sund (now Ittoqqortoormiit) to relieve the population pressure at Ammassalik and in 1925 (as a result of their first expedition) this settlement became a reality (Mikkelsen, 1927). The 1932 expedition  was designed to explore the coastline between Ammassalik and Scoresbysund and to erect houses at strategic points along the coast, with a view to promoting travel between the two areas and to explore the possibility for colonizing the Kangerlussuaq area. Although the expedition was successful, its ultimate aim has never been fulfilled: no journeys have ever been made by Inuit along the entire length of this coast and no permanent settlement was ever established, although overwintering parties have been at Skaergaard most years since 1966 (see above).

During his two first expeditions, Wager had made remarkable strides in elucidating the previously unknown geology of the immense area (perhaps as much as 100,000 km2) between Ammassalik and Scoresby Sund (Wager, 1934), but he was convinced that Skaergaard was worthy of detailed study. With this as a primary goal, he returned in 1935 with a small party, including his brother (a botanist), their two wives, W.A. Deer (a geologist), a medical doctor and a general assistant, together with a party of two Inuit families, forming the British East Greenland Expedition, 1935-1936 (Wager, 1937). They overwintered in a small house which they constructed on what they called "Home Bay" (now Hjemsted Bugt), and they also used two houses that had been erected by the Mikkelsen expedition in 1932. All these houses, along with a further one built by Mikkelsen at Miki Fjord (shown on Wager and Deer's Skaergaard map) have since been destroyed, although they were in good condition until the late 1960s.

Up to this time, the only geologist other than Wager and Deer, who had seen the Skaergaard was S.R.F.Bøgvad who stopped briefly during the Seventh Thule Expedition in 1932 (see: Gabel-Jørgensen, 1935 & 1940, also Spender, 1934, for descriptive accounts of this expedition). Bøgvad did not however publish his findings, and, because his notes where written in code, all his observations were effectively lost on his death.

Weather stations  and older commercial activity

In 1945, because of World War II , the United States established a weather station at the site of the present hunting settlement on Skærgårdshalvø. Remains of this station can still be seen, but by 1966, none of the structures remained standing. In 1949 the station was transferred to Nordre Apulileeq (= Aputitêq), about 45 km to the southwest, probably because the weather at the original site was deemed to be too local.

Eskimo house in Hjemsted Bugt (Home bay) built by the Scoresby Sound Committee (Mikkelsen 1934)A long-standing Norwegian interest in the area led to the establishment of a radio station, known as "Storfjord Radio", at Mudderbugt on the west side of Kangerlussuaq (which is known to Norwegians as "Storfjord", the Scandinavian translation of the Greenlandic name) as part of the International Polar Year. This station operated through 1932-33 and remains can still be seen. Several small huts were also erected around the fjord: at Spækpynten, Bagnæsset and Skåret (on Kræmer Ø), for use by sealers and shark fishers from Ålesund and Tromsø, but falling prices for animal oils, the main product of this industry, led to their abandonment in the 1950s. The characteristic wooden ships (Signalhorn, Furenak, Brandal, Polarbjørn)  which were mostly built around the turn of the century, have now disappeared from the area, but their immense strength and the unparalleled skill of their skippers in these treacherous waters meant that a few of them were still in demand as expedition ships and supply vessels for the weather stations such as Nordre Apulileeq (= Aputitêq), where seven men lived totally isolated except for the yearly ship. Many Skaergaard geologists will remember the cheerful stewards on these ships, with their filling Norwegian food, after a summer on meagre expedition rations. They will similarly remember how the ships, built for shunting ice, rolled in the autumn swell of the Denmark Strait and how quickly the desire to visit the mess-room disappeared. These ships are now all gone. Commercial sealing has virtually ceased due to the pressures of the environmental lobby; geologists now fly and the weather station at Nordre Apulileeq was closed in 1979 due to financial restrictions and the introduction of automatic, telemetred weather reporting. Since that time, the once luxurious facilities at the station have fallen into a ruinous condition. Until recently the only ship visiting Skaergaard was Ejnar Mikkelsen, the local boat from Ammassalik, chartered by the municipality (Tasiilaq Kommune) to transport the hunters, their families, dogs and equipment. Its skipper, Hans Ignatiussen, was a son of one of the couples who pioneered the present overwintering parties at Skaergaard. However, in connection with mineral exploration (see below), Icelandic boats (including an old roll-on-roll-off car ferry) have been chartered in recent years to deliver fuel for diamond drilling and helicopters and the Ejnar Mikkelsen is no more, having been destroyed by the ice in the winter of 1993.

Geological work in the period 1950 to 1970

After Wager and Deer's epic overwintering in 1935-36, there was a hiatus caused by the war and no geologist visited the area until 1953. By this time, it had become apparent that new field observations were necessary and, in addition, many of the original specimens had been consumed through mineral separation and wet chemical analysis (this was, of course, before the days of the electron microprobe and other non-destructive analytical methods). The 1953 British East Greenland Geological Expedition consisted of L.R. Wager (leader), W.A. Deer, G.M. Brown, P.E. Brown, C.J. Hughes and G.D. Nicholls was mounted (Wager,1954). Its objectives were to make new collections from Skaergaard, to examine and map critical areas of the intrusion and to work on other geological features of the immediate neighbourhood, such as the layered gabbros of Kap Edvard Holm and the Kangerdlugssuaq alkaline intrusion. The expedition travelled by chartered Norwegian sealer and was a success, even though it was very modestly funded - there are stories of Wager sweeping up rice, etc. from the floor of the hut when the ship was delayed and rations were exhausted.

Wager's house in Hjemsted Bugt. The house was still standing in the early 1970ies.After 1953, another long hiatus in field work ensued, but during this period a large amount of laboratory work was published, dealing especially with the geochemistry of numerous trace elements. Apart from a brief visit by J.A.V.Douglas in 1962, no geologist came to Skaergaard again until 1966, when there was a new British East Greenland Geological Expedition (Deer, 1967). The main purpose of this expedition was to sample the intrusion by several diamond drill holes: a deep hole in the Hidden Zone and several shorter holes specifically aimed at studying sedimentation phenomena in the exposed layered series. In addition, several of the other Tertiary intrusive centres were to be explored, notably the Kappa Edward Hole, and Lilies areas.  The impetus for deep drilling came from the "MO hole" project: Wager had been to California, attending a meeting of the International Mineralogical Association, where there was a session on layered intrusions. This was the time of the ill-fated "MO hole" project, while a plan was also afoot to drill the Muskox intrusion by the Geological Survey of Canada (realized in 1964) and Wager came to consider the possibility of using a drilling barge at Skaergaard. This turned out to be impractical, but it sparked the interest in drilling and an expedition was planned to extend over two years. However, when Wager died in the later part of 1965, while heavily involved in preparations for the expedition, the leadership passed to W.A.Deer and for various reasons the project was shortened to only one year. The sedimentation study had been Wager's special interest and no-one was forthcoming with sufficient enthusiasm to take it over and it was dropped. Also, the original drilling plan for the Hidden Zone proved too ambitious without considerably escalating the cost of the expedition. Thus after a 349 m hole had been drilled at a site on the eastern shore of Uttentals Sund, starting in the lowest part of the Lower Zone, a second hole of 150 m was drilled at another site on the shore just south of Forbindelsesgletscher, penetrating into the Triple Group. The drill used was a Longyear 35 and core recovery was very high. Several additional holes were drilled to 45 m along a single stratigraphic interval using a "Packsack" drill with a motorized hoist, and about two dozen holes, 5 m deep were drilled in the Trough Bands with a "Dinky" drill. In all 588 m (1930 feet) of core were recovered and has since been stored at the Department of Earth Sciences in Cambridge. Up until the present time, the only studies which have been made of this material were by Maaløe (1974, 1976, 1978, 1987), Nwe (1975, 1976) and Nwe & Copely (1975). The drilling programme did not really live up to expectations in that only about 150 m of the Hidden Zone were penetrated (according to Wager's estimates it is as much as 5 km in thickness) owing to the loss of water from the drill at this depth and indications that the hole was passing out of the intrusion. The sedimentation study visualized by Wager was not carried out, although drill cores for this purpose were obtained. It was ironic that the major hole into the Triple Group penetrated to the stratigraphic zone that was later identified as being gold-bearing, but presence of this zone was not realized at the time.

The 1970s and 1980s

With the death of Wager, a man remarkable in many ways (see  Deer, 1967), British interest in Skaergaard to lapsed. In 1970 and 1971 prospectors from the Northern Mining Company (Nordisk Mineselskab A/S) worked in the area (Brooks, 1972) and in 1971 an American Expedition led by A.R. McBirney began further scientific studies of the Skaergaard intrusion. The McBirney expedition was the first of several, with scientists returning in 1974, 1979, 1985 during this period. Some of the participants who have published their work were: Leslie C. Coleman, E. Julius Dasch, Gordon G. Goles, James D. Hoover, T. Neil Irvine, William P. Leeman, H. Richard Naslund,  William H. Taubeneck, Hugh P. Taylor, Jr., Willem Verwoerdt and C.M. White. H.R. Blank and M.E. Gettings carried out gravity and magnetic surveys that defined the sub-surface form of the intrusion and aerial photography and ground control was completed leading to the publication of a topographic map by the Danish Geodetic Institute (subsequently “Kort og Matrikelstyrelsen, Danmark”) in 1975. These expeditions have led to a new burst of publications on Skaergaard, which, combined with new ways of thinking about layered intrusions in general, is still continuing. In particular, Naslund and Irvine have been especially active and have subsequently returned on independently on a number of occasions. The topographic map referred to above led subsequently to the publication of a geological map (by the University of Oregon) by McBirney with contributions from J.D.Hoover (Marginal Border Series), M.A. Kays (metamorohic basement) and Troels Nielsen (Tertiary volcanic and sedimentary rocks) in !989. A slightly revised edition with petrofabric lineations by Adolphe Nicolas was published in the book on layered intrusions edited by Cawthorn.

At the same time (i.e. 1971), the University of Copenhagen under the leadership of C.K. Brooks began a series of expeditions to the area (in the years from 1972 to 1991, 1978 and 1983 to 1986 excepted) but the object of this work was largely regional, designed to elucidate the magmatic, sedimentological and tectonic features of this important, if not unique, passive continental margin, of which Skaergaard is a part. Personnel on these expeditions at various times came from the Universities at Copenhagen, Århus, Sheffield, Arizona, Stanford, Toronto and Oregon, along with two geologists from the Northern Mining Company in 1982, whose specific, interest was the Flammefjeld porphyry molybdenum deposit on the west side of Kangerlussuaq. (Geyti & Thomassen,1984), which had been discovered by Brooks & Thomassen in 1970.

In the years 1977 and 1978, the area was visited by the Geological Survey of Greenland, involved in regional mapping under the leadership of David Bridgwater (Myers et al. 1979) and, in 1986, two geologists (H-K.Schønwandt and C.K.Brooks) with two assistants visited the area for the Geological Survey with a view to appraising the economic mineral resources (Brooks et al., 1987). They worked in close  collaboration with the Geodetic Institute of Denmark, led by T.I. Hauge Andersson, which was involved in a detailed survey of the area using Transit and GPS measurements, as well as gravity measurements. In preparation for this project, two geodecists visited the area in 1982 along with the University of Copenhagen party and established the air strip in Sødalen, which was first used the same year. In 1985, a hut at Sødalen was erected, with funding from the Geodetic Institute and the University of Toronto and, in 1991, a second, larger hut was erected by Platinova Resources Ltd. nearby.

Other groups vital to Skaergaard research must also be mentioned: University of Arizona/Stanford University and Platinova Resources Limited of Toronto. The Arizona/Stanford work began with an expedition consisting of Denis Norton and Dennis K. Bird in 1981 and continued under the leadership of Bird after his move from Arizona to Stanford, with further expeditions in 1982 and most subsequent years. This work began to look at the hydrothermal effects in the cooling Skaergaard body, work which was subsequently extended to other intrusions and into other areas, but up to that time had been largely ignored but for the stable isotopic work of Hugh Taylor. In association with Bird, Charles E. Lesher of the Lamont-Doherty Geological Observatory (now at the University of California, Davis) and Minik Rosing (Copenhagen) began work on the Mikis Fjord Macrodyke to elucidate the interactions with country rock, a question of great importance in Skaergaard (the macrodykes where formed from very similar or even identical magmas to Skaergaard). At the same time Craig White and Dennis Geist of the University of Idaho, Boise, worked on the adjacent Vandfaldsdalen macrodike.

In 1988 parties from Copenhagen, Stanford, Oregon, Boise (Idaho) and Binghamton (New York) were again in the field. H.R. (Dick) Naslund (Binghamton) and the University of Copenhagen continued in 1989, and the University of Copenhagen accompanied by T. Neil Irvine Geophysical Laboratory, Washington D.C., continued in 1990 and 1991.

Sir Robin Knox-Johnston's Suhaili, a prominent visitor to the Skaergaard in 1991Distinguished scientists who have visited the area are: Professor A. Noe-Nygaard of Copenhagen, the "grand old man" of Danish geology (in 1986, when he was 80 years old), and H.T. Tazieff, the celebrated French volcanologist and adventurer, in 1988. In 1990 a group of Icelandic geologists spent 1 week on the intrusion and a party of distinguished international petrologists (A. Nicolas, A. Boudreau, S. McCallum, I. Parsons, J. Wolff & R.St.J. Lambert) travelling with A.R. McBirney spent somewhat longer. Perhaps these are the harbingers of an accelerated tourism and in 1991, Kangerlussuaq was visited by an expedition led by the celebrated mountaineer Chris Bonington and the equally celebrated yachtsman Sir Robin Knox-Johnston in the yacht "Suhaili", which spent several weeks in an anchorage at the entrance to Uttentals Sund (Bonington & Knox-Johnston, 1992) and in subsequent years further parties of adventurers have put in an appearance.
In 2000, a new gravity survey was carried out by C.K. Brooks and M.B. Kristensen and a comprehensive new collection of hand samples was made under the Danish Lithosphere Centre, while the existing cores were shipped back to the Geological Museum, University of Copenhagen.

Commercial activity

In 1986, Platinova Resources Ltd. of Toronto (subsequently to be registered in Nuuk/Godthåb, Greenland), under the active leadership of its president, Mr. R.A. Gannicott, began exploration of the area  with a view to evaluating it for precious metal deposits - an interest inspired by the published work of the Copenhagen group and the recently established logistic facilities. During this first expedition, interest was aroused in Skaergaard, largely as a result of geochemical prospecting, by Platinova and the Greenland Geological Survey (Brooks et al., 1987).  More comprehensive work was done in 1987 and 1988 from a helicopter camp in Sødalen. In 1987 gold anomalies were found at several localities close to the Triple Group (upper part of the Middle Zone). These showings were sampled in more detail by climbers in 1988 with very promising results. This work showed significant quantities of gold, associated with sulphides occurring in particles up to 40m in size, along with electrum (Bird et al., 1991). The gold can readily be separated by flotation. However its genesis is at present unknown and the work has shown complications at this level in the intrusion which call for new detailed studies. Comprehensive drilling was carried out in 1989 and 1990, during which time an important Pd-rich zone was discovered about 20 metres below the gold zone.

During the  period 1986 to 1991, the mineral exploration activity, referred to above, was in full swing and 16,600 metres of diamond drill-core from 27 holes and 7 wedge cuts had been taken.and long runs of channel and chip samples were recovered. This confirmed that mineralization was continuous over an area of about 15 square kilometres or about 60% of the area defined by surface mineralization. Resource estimates were calculated by the Canadian firm of Watts, Griffis and McOuat Limited using a two metre average width for the gold zone with a specific gravity of 3.23 as approximately 28,000,000 tons grading 2.5 grams/ton at a cut-off grade of 2.20 grams/ton, which is raised to around 43,000,000 tons grading 2.38 grams/ton at a cut-off grade of 2.0 grams/ton. The global estimate is that there are over 5 million ounzes Au , which is a large deposit by any standards. In addition there are significant quantities of palladium, platinum, copper and titanium: valuable co-products, which could contribute significantly to the operation. No estimates have been made of the value of the underlying palladium-rich horizon at this time, but it underlies a similar area and is 3 to 6 metres thick with an average of about 2 gm/tonne Pd. These figures are quoted from the 1993 Annual Report to Shareholders of Platinova Ltd. and seem to indicate amounts of as much as 50 m. oz.

This major gold find was first reported in the Danish newspaper Jyllandsposten (Nov. 13th) by C.K. Brooks which led in the following days to a globally extensive media coverage. The economic aspects were described briefly by Brooks (1990) and by Nielsen (1990) and Nielsen & Schønwandt (1990). The first scientific note was published in Economic Geology  (Bird et al. 1991). In late 1990 new excitment surfaced in the media with the reported discovery of promising amounts of precious metals in the nearby Kap Edvard Holm gabbro (Bird et al., 1995) and although by 1993 commercial activity in the area had ceased, it is clear that it is only a matter of time before the prospectors return. The deposit has been evaluated to be marginal and gold prices have been low throughout the 90s. However other precious metals have increased markedly in value due to their use in autocatalysators. Thus, by 2001 the price of palladium had risen 10-fold to over $1000 per ounce.

There is little doubt that the gold find will also lead to a greatly increased scientific interest and the large amount of high quality drill-core material available for this reseach is, as yet, virtually untapped. The drill holes have also been used as holes of convenience in a heat flow study by the universities of Copenhagen and Århus (at present unpublished).

Trends in Skaergaard research

Skaergaard research falls into four distinct phases: mapping and general description of the intrusion in the 1930s; more detailed laboratory work , largely geochemistry, in the 1950s and '60s; renewed fieldwork followed by new interpretations in the 1970s and early 1980s; discovery of precious metals and drilling in the late 1980s. In the 1990s, it is not easy to discern which direction research is taking, proceeding on many fronts.

The 1930's saw the early work on the intrusion, it was mapped, its salient features described and hypotheses presented to explain the origin of these features. At this time, the main thrust was to explaining the "normal" trend of igneous fractionation and resolving the Bowen-Fenner controversy as to whether such fractionation produced granitic end products or led to a trend of iron enrichment. Wager & Deer's work (Wager & Deer, 1939) achieved instant acclaim as it was the most detailed study of a gabbro body available. Their work showed that under the conditions prevailing in the Skaergaard magma chamber the trend was one of iron enrichment and only negligible amounts of granite were generated.

During the 1950s and '60s, ideas of crystal settling were refined, but above all this period saw a wealth of information on the behaviour of a great number of elements during fractionation of a basaltic magma. In addition, some early isotopic information was published. To this end Wager and his co-workers, notably R.L. Mitchell and E.A. Vincent, began to work with new analytical methods - first optical spectroscopy, later neutron activation and mass spectrometry - that were to become of central importance in petrology in the 1960s and '70s, especially in connection with newly acquired samples from the moon and deep oceans. As these new methods were often first applied to Skaergaard rocks and minerals, Skaergaard research laid the foundations of much of what was to come in petrological advances. Wager did not concern himself with experimental methods, but always insisted that his group observed Nature and drew their conclusions from these observations, rather than indulging in experimental petrology which was very much in vogue at the time.

The 1970s and '80s saw, to a large extent, a return to the type of research of the 1930's - field observations and their interpretation in the light of current theoretical ideas. When being presented with the N.L. Bowen Award of the American Geophysical Union in 1990, A.R. McBirney had this to say about his first visit to Skaergaard (McBirney, 1991): "When I first visited that magnificent place in 1971, I was sad that Wager had left so little for us to explain. All I could contribute to his elegant account of differentiation by crystal fractionation would be a bit more evidence in support of the obvious. Now 20 years later, look where we are. We have taken the intrusion apart and scrutinized it in great detail. We've mapped it, run geophysical surveys, analysed it for every element and isotope conceivable, and what do we have? Most people would say a shambles". In short, McBirney was telling his audience that, in spite of all the effort, understanding of the precise processes which had formed Skaergaard are still very imperfectly known.

The '70s and '80s, were the decades when the original interpretations were questioned: what is the form of the intrusion? - had crystals really sunk in the magma? - what is the real differentiation trend? - and what is the extent of sub-solidus alteration? Concepts of fluid dynamics came to the forefront, and obscure minor elements were relegated to the back seat. Interestingly, enough in the late '80s there was a tendency for return to Wager & Deer's original ideas - McBirney (1985) questioned the idea of double-diffusive convection (originally proposed by McBirney & Noyes, 1979) and a number of authors (McBirney & Naslund, 1990; Morse, 1990; Brooks & Nielsen, 1990) championed the compositional trend proposed by Wager & Deer but rejected by Hunter & Sparks (1987). These points of view are still apparantly unsettled.

The late 1980s and early '90s are marked by a renewed interest in the intrusion, sparked by the discovery of precious metals. Oddly enough Skaergaard rocks were some of the earliest to be analysed for trace amounts of gold, silver and palladium (Vincent & Smales, 1956; Vincent & Crocket, 1960; Adams, 1961), while Wager, Vincent & Smales (1957) in their study of sulphides in Skaergaard made a very important contribution to our understanding of orthomagmatic ore deposits. None of these authors suspected that the intrusion might one day turn out to host a world class precious metals deposit.

In the near future, we can perhaps expect an increased use of geophysics to delineate the sub-surface parts of the intrusion, increased use of microbeam techniques to acquire elemental and isotopic data on a microscale, greater attention to the role of fluids and new detailed studies of the stratigraphic variations. Newcomers to Skaergaard are frequently amazed to find just how few samples have actually been studied. This situation will doubtless change with the availability of many kilometres of diamond drill core. In the citation of McBirney quoted above, he goes on to say:
"I think it is great to see so many entrenched ideas being challenged. It was impossible to make any headway until we rid ourselves of a lot of cherished beliefs. As a result, we can now start putting the pieces back together and I am confident that we are gradually seeing our way out".

In a recent review of magmatic differentiation, Wilson (1993) made clear the overwhelming importance of the Skaergaard studies to the development of ideas and our understanding of the differentiation of basic magmas. For example she writes: "The Skaergaard intrusion, east Greenland, has, for the past 50 years been cited as the classic example of in-situ differentiation of basic magma" and goes on to show that the evidence, which continues to accumulate, is by no means unequivocal and we are still a long way from achieving a consensus in exactly how to interpret this evidence.

This compilation represents the pieces, fundamental to igneous petrology, which now wait to be put together, along with the data yet to be gathered.

Figure references

Mathiassen, T., 1935. Skrælingerne i Grønland. Udvalget for Folkeoplysnings Fremme. 140 pages.
Mikkelsen, E., 1934. De østgrønlandske eskimoers historie. Gyldendal. 202 pages. Photos by M. Spender and U.M. Hansen.

© 2003