Age of High-Mg Granitoids of the Nyukozero Massif, Karelia

摘要

The Nyukzoero Massif is located in central Karelia, south of Lake Nyuk (Fig. 1). It is the largest (>100 km~2 in area) high-Mg granitoid massif in the Baltic Shield. On the southern and eastern flanks, the massif cuts vol-canosedimentary rocks of the Khedo―Bol'shozero-Nyuk structure, which is the northern continuation of the Hattu schist belt representing the eastern branch of the large Ilomantsi greenstone belt in eastern Finland. The western and northern contacts of the massif are poorly exposed. Host supracrustal rocks mainly consists of gray wackes, which are compositionally similar to rocks of the Hattu schist belt, and occur as xenoliths in the massif.