ABSTRACT: Mıe lice-Kıılp area lies on the southern, whilst the Çökekyazı-Gökay district is situated dose to the norttam margin d the Bitlis massif. In both districts, there are lithologioal units pertaînîngf to the rock groups of the Bitlis massif called lower ami nppe associations. Among1 these units metequartelte marble, micascMsfc, gneiss and amphibolites are the most {widespread. The gneisses and ampbibolites are only emeoiimierecl in the lower, whilst the others are observed in the bith associations. The metaquartzite, marble and oıica-scMsts have been derived from sedimentary parents; certain gneisses tana ampMbolites are the derivatives of sedimeııtary, whereas the others come from igneous origin The gneisses, some of which, exiMt a- well developed scMstosity are locally found iıı alternation with the metaqpartzltes ani merbles while sonne others pass laterally in to the mica-schists» This situation indicates that some of the gneisses are of sedimentary (pelitic rocks) origin. The others of the gneisses, on the other hand, show a relatively massive structure and are observed as bodies cutting locally the other metamorpMes. This implies that these gneisses may be of igneous ( acidic igneous) origin In places, the amphibolïtes are seen In alternation with quartzmieeschists and are locally encountered as massive bodies cutting the mleanschists. These evidences show that some of the aimphifeolites have been resulted from the metamorphism of sedimentary rocks» that is Impure limestones or marls, and the others have been derived from the metamorphism of basic Igneous roeks. This interpretation concerning with the origin of the amphibolites< is also- supported by Bb/Sr ratio values obtained `via XKF analyses, and microsooplo studies.