III. Fra Tryssil

Abstract

Forkortet: It is a pecularity of the border line of Southern Norway, that it makes a bend into Sweden North of the 60th parallel. The region within this bend is the district of Trysil. The geology here is not very intricate, as one meets with 4 zones, not difficult to distinguish. Note the little sketch map on p.5. The Sparagmite Formation forms the western part consisting chiefly of feldspar- bearing sandstone. The age is early Cambrian. The stratification is disturbed. Then follows a stripe of granitic rock of Archaean age. It widens southwards. Most of it is a typical granite, the Trysil Granite. Mr. Meinich made the statement that this Trysil Granite was younger than the Sparagmite formation. The present author has revisited his chief locality (The Hundsil rivulet), where he thought to have observed granite-dykes penetrating a red quartzite; but it was found that his quartzite was nothing else than a finegrained gra- nite sometimes rich in quartz. One observes here two varieties of granite, one middlegrained occurring in dykelike parts within denser king of the same rock. The porphyry of our little map is sometimes a quartz-porphyry containing visible grains of quartz besides feldspar; in other cases one sees only feld- sparcrystals.