Basiska bergarter, gångbergarter, sedimentbergarter och breccior i Vaggerydssyenit : en undersökning i protoginzonen vid Vaggeryd
The Protogine Zone is a system of steep shear zones running approximately parallel to the boundary between the Svecofennian and the Southwest Scandinavian orogens of southern Sweden. The geological nature of the zone is not very well known, mainly because detailed mapping has not begun until recently. This work is the beginning of an attempt to start changing this situation. An area of l km², situated 3 km north of Vaggeryd in north-western Smaland, has been mapped in detail. 
The main rock types in the investigated area are syenite and finegrained 
mafic rocks. Associated with these two rock types are breccias. 
Other rock types include volcanics and sandstones. There is also a 
Fe-Ti mineralization. 
The syenites consist of perthitic potash feldspar (36-84 %, mean 
value 61 %), plagioclase (0-19 %, mean value 5 %), clino- and orthopyroxene 
(0-18 %, mean value 9 %), occasional olivine, apatite (mean 
value 2 %) and opaques (mean value 6 %). 
Syenites, aged about 1200 Ma, appear at a number of locations along 
the Protogine zone. They are thought to be closely related to the 
zone. So are also the mafic rocks called "hyperites". Radiometric 
datings of some "hyperites" have shown that they are about 1450 Ma 
old. There is however evidence of several generations of these 
rocks, so some could be younger than this. 
Several details concerning the breccias made the writer infer that 
the breccia is rheomorphic, and also that the syenite and the mafic 
rocks have intruded at approximately the same time. Such details 
include xenoliths of the mafic rocks in the syenite, veins of syenite 
in the mafic rocks, red feldspar-crystals and also partly assimilated 
syenite xenoliths in the mafic rocks. In the mapped area there 
is also a mafic dike intruding the syenite, and chilling against it. 
These facts should also mean that at least some of the mafic rocks 
along the Protogine Zone are younger than 1450 Ma. 
The volcanic and sedimentary rocks, which appear in the syenite, are also interesting. A comparison between the volcanics of the mapped area and the facts known about other volcanic rocks in Smaland has been made. The volcanics outside the mapped area all seem to be older than 1700 Ma. The volcanics of the investigated area intrude both the 1200 Ma old syenite and the mafic rocks, and are therefore younger than these. The sedimentary rocks locally preserve primary sedimentary textures, but they are mostly contact metamorphosed. 
The main ore minerals of the investigated mineralization, which appear in mafic rock are ilmenite, hematite and magnetite. There are three other known mineralizations along the Protogine zone containing Fe-Ti minerals, alloccuring in "hyperite": Langtjarn, Smalands Taberg and Ranshult.