These studies were carried out from 1963-1967. Outcrops at the Lukmanier road gallery yielding important evidence have been partly covered since. The study is concerned with fabric development and related metamorphism, conclusions concern relations between basement and cover, Gotthard massif and Lepontine Nappes, nappe movement and structural development. There is disagreement in important points with work done later in the same region (Chadwick 1968; Thakue 1973). There is no space here to

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... uss this in detail but comparison will make the differences obvious. THE LUKMANIER REGION: BOUNDARY BETWEEN AUTOCHTHONOUS BASEMENT + COVER AND LEPONTINE NAPPES Aarand Gotthard-massifs are parts of the variscan basement underlying the alpine chain. They are deformed by a first slaty cleavage (sx) forming a fan and strong stretching upward (strx). strx fans along the strike, lying down the dip of sx in the strike culminations of both massifs. Urseren-Curaglia-and Disentis-synclines are pinched between these massifs and include a further basement slicethe Tavets'ch massif. The Lukmanier region is the most southerly part of the Gotthard massif and the S margin of the autochthonous basement. Its rocks consist of variscan granite-(Streifengneis, Riesenaugengneis) and para-gneisses (e.g.: Tremola series) + posttectonic variscan intrusions (e.g. : granite : Medelser granite ; diorite : Cristallina diorite). Granite gneisses were strongly flattened, stretched and partly refolded before the posttectonic intrusions arrived. This is seen clearly N