Kursun ja Sallan kartta-alueiden kalliopera - arkisto.gsf.fi ...

Lauerma, Raimo 1995 . Kursun ja Sallan kartta-alueiden kalliopera . Summary :
Pre-Quaternary rocks of the Kursu and Salla map-sheet areas . Geological Map
of Finland 1 : 100 000. Explanation to the maps of Pre-Quaternary rocks, 3643
Kursu and 4621 + 4623 Salla . 40 pages, 15 figures and 5 tables .
The Kursu and Salla map-sheets cover an area of about 1600 km2 in northeastern
Finland, a few tens of kilometers north of the Arctic circle and next to
the Russian border . In the greatest part of the Kursu map-sheet area and in the
southwestern part of the Salla map-sheet area the bedrock is composed of various
granitic and migmatitic rocks . The greatest part of the Salla maps-sheet area
belongs to the Salla schist/greenstone complex composed of various metasedi-
ments and metavolcanic rocks .
In the western part of the Kursu map-sheet area the granitic and migmatitic
rocks resemble the Archean granite gneisses of eastern Finland, but radiometric
age determinations have given Proterozoic ages . Closer to the Salla schist area
the granites are homogeneous . No basal conglomerates have been found . The
metadiabases of the schist complex have been dated by U-Pb methods on zircons
and titanites as 2210 Ma old . The granites intruded the metadiabases about
1800-1810 Ma ago . The youngest rocks of the area are NW-SE trending differentiated
diabase dykes intruded about 1122 Ma ago .
The folding has been gentle and the mostly subhorizontal fold axes trend about
N-S . Major fault lines trend N 40°-60° W .
The text is in Finnish with figure and table captions and the summary in
English .
Key words (GeoRef Thesaurus, AGI) : areal geology, explanatory text, bedrock,
diabase, Proterozoic, absolute age, Salla, Finland
Raimo Lauerma
Geological Survey of Finland
F1N-02150 Espoo, Finland
ISBN 951-690-591-9
Vammalan kirjapaino Oy 1995
Present address :
Iltatie 10 C 8
FIN-02210 Espoo