Litho-tectonic sequence and their regional correlation along the Lohit and Dibang valleys,eastern Arunachal Pradesh

Geological mapping between Lohit and Dibang valleys of eastern Arunachal Pradesh reveals the existence of five thrust bound tectonostratigraphic units. In ascending structural order from SW to NE these are: (1) Sewak Group, (2) Lalpani Group, (3) Mayodiya Group, (4) Tidding Formation and (5) Lohit plutonic complex. This differs from previous mapping, because the three tectonostratigraphic units (Sewak, Lalpani and Mayodiya) were grouped under a single unit, referred as the Mishmi crystallines. The low-grade metamorphics of the Sewak Group occur at two different tectonic levels, one as persistent belt in the foothills and the other in the tectonic window beneath the high-grade metamorphics of the Mayodiya thrust sheet in the Higher Himalaya. The Tidding suture is the southeastern extension of the Indus-Tsangpo suture zone.