Full resolution (JPEG) - On this page / på denna sida - Sidor ...
<< prev. page << föreg. sida << >> nästa sida >> next page >>
Below is the raw OCR text
from the above scanned image.
Do you see an error? Proofread the page now!
Här nedan syns maskintolkade texten från faksimilbilden ovan.
Ser du något fel? Korrekturläs sidan nu!
This page has never been proofread. / Denna sida har aldrig korrekturlästs.
ADOLF HOEL
To the north of Oldervikvand and in Hakstabfjeldet we find an
igneous rock, which according to Schetelig is a pe rid o tite, an olivin*
bearing abyssal rock with the prominent minerals: olivine, monoclinic and
ortho*rhombic pyroxene (1 h er z o 1 i t e). This peridotite is the chief igneous
rock of the southern part of Seiland. Its position in relation to the gneiss
may be seen in Fig. 3, where we see the gneiss (to the right) with a
sleep angle of inclination, dip under the peridodite.
The lherzolite on the south slope of Tverfj eldet is intersected by a large
number ot f e m i c*
dykerocks. According
to Schetelig these are:
1. O 1 i vine gab*
bro: prominent mine*
rals: bytownite, mono*
clinic pyroxene, olivine
and brown amphibole.
2. D unite: pro*
minent minerals: oli*
vine, green spinel and
chromite.
3. Amphibolite:
prominent minerals:
brown amphibole, oli*
vine, pyroxene, both
monoclinic and ortho*
rhombic, and plagio*
clase.
4. Biotite*am*
phi bo lite: prominent
minerals: biotite and green amphibole with nuclei of diopside.
5. Pegmatitic amphibole*gabbro: prominent minerals: la*
bradorite and amphibole. Coarse=grained dykerock.
6. Hornblendite: prominent minerals: brown amphibole and
biotite. Coarse*grained dykerock.
All these dykes had a strike of approximately N—S, and their thickness
was from 0,5 meters up to several meters.
Besides these femic dykerocks I also found on the outer slope of
Tverfjeldeta nepheline*gneiss with «Augenstructure» which according
to Schetelig is a protoclastic, schistose dykerock with nodules of nephe*
Fig. 3. Hakstabfjeld seen from WSW. Gneiss to the right,
periodite to the left.
114
<< prev. page << föreg. sida << >> nästa sida >> next page >>
