Blyglansforekomst på Krækkjeheia, Hardangervidda.

Abstract

A lead deposit near Krækkjeheia, Hardangervidda. This short paper presents the main results of an investigation of a galenaspalerite showing on the mountain plateau of Hardangervidda, 160 kms. west of Oslo. The sulfides occur as very irregular and economically insignificant coarse-grained disseminations in thin lenses of milky quartz and calcite. These lenses have been emplaced between the almost flat-lying bedding-planes of Cambrian phyllites which overlie steeply dipping Precambrian gneisses baving a N-S strike (see Fig. 1). The mineralization has been localized in the phyllites along a N-S-striking fault in the Precambrian rocks. This fault, which shows a throw of not more than 5 metres, moved in post-Caledonian times, flexing, and in parts breaking, the overlying Cambrian layers. The flexing opened up lenticular spaces between the bedding-planes, in which spaces the quartz-calcite-sulphide mineralizationwas deposited (see Fig. 2). The occurence is of scientific interest in that it is the most westerly representative yet confirmed of a belt of Pb-Zn mineralization which strtches northeastwards along the southern front of the Caledonides and eventually links up with Swedish occurences of the so-called \"Laisvall-type\".