In August, 2003, I spent a month with Dr. Andy McDonald (Laurentian
University) in the Larvik region, southern Norway, doing field work for a
collaborative project on the alkaline pegmatites of the Larvik Alkaline Complex.
The LAC is located ~ 90 south of Oslo and is part of the Oslo Rift Valley which
was active 305-240 Ma ago. The LAC (297-292 Ma) is 40 km across and
consists of intermediate rocks of monzonitic composition. There are
approximately 10 'ring sections' in this complex. In addition to the
intermediate rocks ('larvikite' and 'lardalite'), late-stage alkaline pegmatites
can be found in all of the ring sections. To date, 175 different mineral
species have been found in these pegmatites.
|
|
|
|
|
|
|
|
|
Laven pegmatites (aegirine clump) |
|
|
|
|
|
|
|
|
|
|
|
|
Laven pegmatites (aegirine clump) |
|
|
|
|
|
|
|
|
|
|
|
|
|
Laven pegmatites (aegirine clump) |
|
|
|
|
|
|
|
|
|
|
|
|
Andy and Alf Olav on Laven |
|
|
|
|
|
|
|
|
|
|
|
|
Andy and Alf Olav on Laven |
|
|
|
|
|
|
|
|
|
|
|
|
|
Plumose feldspars in Laven pegmatite |
|
|
|
|
|
|
|
|
|
|
|
|
Sven checking out the Stokksundholmen pegmatite |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Aroyskjaera rhythmically-banded larvikite |
|
|
|
|
|
|
|
|
|
|
|
|
|
Red feldspars and aegirine in pegmatite on Aroyskjaera |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Red feldspar and aegirine in pegmatite at Aroyskjaera |
|
|
|
|
|
|
|
|
|
|
|
|
Pegmatite field at Aroyskjaera |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
"Slow speed" sign in Langesundsfjord |
|
|
|
|
|
|
|
|
|
|
|
|
|
Skudesundskjaerene pegmatite (tadzhikite type locality) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Saga Pearl quarry pegmatite |
|
|
|
|
|
|
|
|
|
|
|
|
Saga Pearl quarry - drill |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Tuften quarry overlooking Langesundsfjord |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Andy showing proper use of a geological hammer - fresh crab! |
|
|
|
|
|
|
|
|
|
|
|
|
Proper geological hammer technique |
|
|
|
|
|
|
|
|
|
|
|
|
|
Enjoying the fruits of Andy's labours! |
|
|
|
|
|
|
|
|
|
|
|
|
|
Andy at the somewhat wet Jahren pegmatite |
|
|
|
|
|
|
|
|
|
|
|
|
|
Yxney pegmatite, Osteroya |
|
|
|
|
|
|
|
|
|
|
|
|
Yxney pegmatite, Osteroya |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Verdens Ende - End of the World |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Bratthagen interior pegmatite |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Deepsea fishing - mackeral |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Klastad quarry, Andy for scale |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Ramsas prospect, Alf Olav and I |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Kuoya, large blue feldspars |
|
|
|
|
|
|
|
|
|
|
|
|
Ula pegmatite, skeletal amphibole |
|
|
|
|
|
|
|
|
|
|
|
|
|
Ula pegmatite, skeletal nepheline |
|
|
|
|
|
|
|
|
|
|
|
|
Ula pegmatite, skeletal magnetite |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Stavern street sign - Farts dampre! |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Deepsea fishing - supper!! |
|
|
|
|
|
|
|
|
|
