NJG78-4-02
1998
Stretching lineations and structural evolution of the Kalak Nappe Complex (Middle Allochthon) in the Repparfjord-Fægfjord area, Finnmark,northern Norway
78
4
pp. 277-289

Two small klippen of the Kalak Nappe Complex (Middle Allochthon) overlie the Komagfjord Antiformal Stack (Lower Allochthon) in the Repparfjord-Fægfjord area of the Caledonides in Finnmark. The Gargia Nappe, the lowest imbricate of the Kalak Nappe Complex, forms the base of both klippen; this nappe comprises pelitic to semi-pelitic schists and mylonites. In the western klippe, the Gargia Nappe is overlain by strongly sheared psammites of the Billefjord Member (Klubben Fm., Olderfjord Nappe). Generally, the mylonites have clustered stretching lineations reflecting SSE- or SE-directed movement. In the lowest part of the mylonites, however, the lineations have a great circle distribution, with SE- to E-directed movement. Subsequent deformation, related to out-of-sequence brittle oblique thrusting cutting both the mylonites and the underlying Komagfjord Antiformal Stack, folded the mylonites. The rotation in the stretching direction of the mylonites allows a restored length of the Lower Allochthon to be modelled at 296 km, a shortening of 54% and a time averaged thrusting rate of ca. 0.87 cm yr-1.

A. H. N. Rice, Institut fur Geologie, Geozentrum, Universität Wien, Althanstrasse 14, Vienna, A-1090, Austria

0029-196X