Abstract
Over the area extending about 15 km north of the inner part of Bjørnesund, near Fiskenæsset (fig. 16), numerous conformable layers of anorthositic rocks occur within gneisses. The rocks have been metamorphosed in the amphibolite and granulite facies, and affected by five episodes of folding. Only minor intrafolial and isoclinal folds have been recognised from the early phases (F1 and F2) but major isoclinal folds which were initially recumbent with NE trending axes were produced by F3 folds. These were subsequently refolded by F4 and F5 fold phases which produced major and minor tight to open upright folds with axial planes striking BSE and NE respectively. It is possibie that the anorthosites have been affected by all five episodes of folding, but only F3 to F5 have been recognised in these rocks with certainty.
Highlights
The stratigraphy of the anorthosite complex as described by Windley (1970, and this issue p. 41) has been used to interpret the structure in this area
Near Fiskenæsset the comp1ex is generally folded into an isoclinal syncline, in this area it can be shown that the earliest major folds affecting the complex are Fa antic1ines and sync1ines. These folds are isoclinal and in some cases the complex in one limb of these folds has been totally reduced to inclusions of anorthositic and gabbroic rocks in the gneisses
A little further north an amphibolite c10sure is surrounded by gneisses which contain relics of the anorthosite succession
Summary
The stratigraphy of the anorthosite complex as described by Windley (1970, and this issue p. 41) has been used to interpret the structure in this area. The southem slopes of the mountain are made of anorthosite (zones 6-8), and the rocks here are affected by major F 5 folds. This youngs towards the south since peridotites with chromite layering (zone 2) occur at its northern margin ( at locality 3). Deformed homogeneous leucogabbro (unit 5) oceurs further south within the outcrop, and amphibollte (zone 9) occurs on its southern margin.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
