Greenland
Oh,
no - too much for one page. There are several intrusions in
Greenland, that should be dealt with on separate pages.
A
short overview:
There are 10 major intrusive complexes of
alkaline igneous rock in an area of 200 by 70 km. Their age is
1,32-1,12 bio years. Some are really small (a few hundred meters),
others cover more 1000 km². Except for Kola and to a much lesser
degree the Monteregian Hill of Québec, Canada, there is no
other area in the world with such an accumulation of alkaline igneous
intrusions.
Predominantly
the intrusions consist of alkaline to peralkaline rocks, in part
over- and in part under-saturated in silica. Ilimaussaq is the only
intrusion that contains both rock types.
The
localities:
Ilimaussaq
- including Kvanefjeld, Kangerluarsuk, Tasseq,
Eriksfjord ...
Narssârssuk/Igaliko
Ivigtut
Kungnat/Groennedal-Ika
- Kap Washington Volcanics:
Lavas, trachytes, rhyolites. Riebeckite.
- Hvalroso: Essexite.
Analcime, augite, biotite, labradorite, magnetite, nepheline,
olivine.
- Hold with Hope: Alkaline
basalts, olivine augitite. Augite, biotite, nepheline, olivine.
- Passagehoje:
Nepheline-olivine tephrite sill.
- Arnold Eschers Land:
Alkaline basic lavas. Analcime, clinopyroxene, ilmenite, kaersutite,
magnetite, nepheline, olivine, perovskite, plagioclase, rhoenite.
- Kap Parry: Peralkaline
granites, syenties. Aegirine, quartz, riebeckite.
- Forchhammer: 120km²,
peralkaline syenites on basalt sills. Aegirine, mphibole grp.,
pyroxene grp., quartz.
- Theresabjerg and Pictet
Bjerge: 8x4km, peralkaline syenites. Aegirine, aegirine-augite,
biotite, hornblende, quartz.
- Werner Bjerge: 17km in
diameter. Pyroxenites, syenogabbros, syenites, foyaites, , nepheline
syenite.pegmatites. Aegirine, aegirine-augite, albite, analcime,
arfvedsonite, barkevikite, cancrinite, lamprophyllite, lavenite,
mosandrite, narsarsukite, nepheline, riebeckite, sodalite.
- Kap Brewster: Pebbles of
alkaline rocks in conglomerates.
- Kap Dalton: Alkaline
pebbles in comglomerate. Malignite, tinguaite. Aegirine, analcime,
leucite, nepheline, nosean, orthoclase, perovskite, pyroxene grp..
- Borgtinderne: 10x8km
under ice and snow. Nepheline syenite in basalts. Aegirine,
aegirine-augite, amphibole grp., apatite grp., biotite, magnetite,
nepheline, plagioclase, sodalite, titanite.
- Lilloise: 10x5km.
Peridotites, olivine gabbros, veins and dykes of syenite.
Aegirine-augite, analcime, biotite, perthite.
- Sorgenfri Gletscher and
I.C.Jacobsen Fjord: 2 bodys of nepheline syenite.
- Batbjerg: Pyroxeneite,
jacupirangite, ijolite, urtite, syenites, granite. Aegirine,
amphibole grp., analcime, biotite, clinopyroxene, diopside,
hornblende, kalsilite, leucite, melilite, natrolite, nepheline,
olivine, pectolite, phlogopite, quartz, thomsonite, wollastonite.
- Gardiner: 5km in
diameter. Ultramafic complex, shonkinite, nepheline and soldalite
syenites, melilitolite, ijolite. Aegirine, aegirine-augite, albite,
apatite grp., biotite, calcite, clinopyroxene, hornblende,
magnesio-arfvedsonite, magnesio-katophorite, magnetite, melanite,
melilite, microcline, nepheline, olivine, perovskite, phlogopite,
pyrochlore, ramsayite, sodalite, spinel.
- Kangerdlugssuaq: 33km in
diameter. Basalt xenoliths, four ring-units: quartz nordmarkite,
pulaskite, pulaskite with nepheline/ sodalite, foyaite. Aegirine,
aegirine-augite, analcime, astrophyllite, biotite, chevkinite,
eudialyte, hiortdahlite, katophorite, kentbrooksite,
kupletskite, lavenite, magnesio-arfvedsonite, melanite, nepheline,
perovskite, perthite, plagioclase, sodalite.
- Kap Edvard Holm: Gabbros,
syenitic, granophyric rocks. Aegirine, aegirine-augite, aenigmatite,
albite, amphibole grp., apatite grp., arfvedsonite, astrophyllite,
biotite, chevkinite, fayalite, ferroaugite, ferroedenite,
ferrorichterite, fluroite, hastingsite, hedenbergite, ilmenite,
microperthite, quartz.
- Kraemer: Peralkaline
quartz syenite. Aegirine, arfvedsonite, astrophyllite, fluorite,
perthtie, quartz, zircon.
- Kialineq: 30x10km, quartz
syenite and granite plutons. Aegirine-augite, aenigmatite, amphibole
grp., biotite, chevkinite, fayalite, ferroaugite, ferrohedenbergite,
ferrohornblende, quartz.
- Tugtilik: Dyke swarm,
dolerites, alkaline rock types. Aegirine, analcime, biotite,
clinopyroxene, diopside, feldspar grp.,garnet grp., nepheline,
olivine, pargasite, perovskite, sodalite.
- Nagtivit: Nepheline
syenite blocks.
- Ubekendt Ejland: Alkali
basalts, monchiquite, lamprophyric dykes. . Aegirine, amphibole
grp., analcime, biotite, melilite, nepheline, salite.
- Quigussaq: Unaltered
lamprophyr-carbanoatite intrusions.
- Holsteinsborg: Lamporite,
kimberlite dykes. Apatite grp., clinopyroxene, diopside, feldspar
grp., ilmenite, olivine, perovskite, phlogopite, priderite,
richterite, serpentine grp., spinel.
- Qaqarssuk: 15km²,
carbonatites, fenites. Aegirine, albite, amphibole grp., ankerite,
apatite grp., dolomite, magnetite, olivine, pyrochlore, pyrochlore,
quartz.
- Sarfartoq: Carbonatite,
fenites. Aegirine, apatite grp., biotite, calcite, feldspar grp.,
garnet grp., hornblende, ilmenite, magnesio-arfvedsonite, magnetite,
olivine, phlogopite, pyrite, pyrochlore, richterite,
tetraferriphlogopite, zircon.
- Tupertalik: 500x200m,
carbonatite. Amphibole grp., apatite grp., calcite, clinopyroxene,
diopside, dolomite, magnetite, olivine, phlogopite. Spinel, zircon.
- Frederikshabs Isblink:
Carbonatite, melilitite, phonolite, nephelinites. Amphibole grp.,
apatite grp., calcite, clinopyroxene, feldspar grp., leucite,
magnetite, melanite, melilite, olivine, perovskite, phlogopite,
schorlomite, titanite.
- Iluilarssuk: Lamprophyric
carbonatite dykes. Aegirine-augite, amphibole grp., ankerite,
biotite, calcite, dolomite, hornblende, magnetite, olivine,
phlogopite, salite.
- Nunarssuit: 45x25km,
gabbro, syenite, granite, not all alkaline. Aegirine,
aegirine-augite, aenigmatite, albite, amphibole grp., astrophyllite,
augite, biotite, clinopyroxene, fayalite, feldspar grp., fluorite,
hornblende, oligoclase, olivine, perthite, quartz.
- Bangs Havn: Syenites,
alkali granite.
- Puklen: 4x2km.
Peralkaline granite, syenites. Aegirine, aegirin-augite,
aenigmatite, arfvedsonite, astrophyllite, augite,biotite, fayalite,
hornblende, microcline, orthoclase, quartz, riebeckite.
- Isortoq: Alkali gabbro,
syenite, granite, larvikite.
- Tugtutoq: Granites,
syenite., olivine diorite. Aegirine, aegirine-augite, aenigmatite,
amphibole grp., analcime, apatite grp., arfvedsonite, astrophyllite,
barkevikite, biotite, fayalite, ferroaugite, fluorite, hedenbergite,
hornblende, ilmenite, magnetite, nepheline, olivine, perthite,
quartz, riebeckite, sodalite, zeolite grp.
- Dyrnaes-Narssaq: Gabbro,
syenites. Qugite, biotite, quartz.
- Qagssiarssuk: Diatremes
of carbonate tuffs, alnoite, peridotite, pyroxenite, lamprophyre.
Ankerite, dolomite.
- Klokken: Alkali gabbro,
syenite, pegmatites. Aegirine, arfvedsonite, biotite, clinopyroxene,
feldspar grp., hastingsite, ilmenite, katophorite, magnetite,
olivine, plagioclase, quartz.
- Nunatak, NE Greenland:
Melilites, basanites. Ilmenite, perovskite.
- &Suggested
reading:
- Woolley, A.R.: Alkaline Rocks
and Carbonatites of the World. Part 1: North and South America.
British Museum (Natural History), London, 1987
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