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This special publication presents a synoptic and critical review of the existing geoscientific knowledge of the Bhutan Himalaya.The section of tectonostratigraphy brings out the regional description of all the fomrations exposed in Bhutan. An interesting feature of this contribution is the detailed description of quaternary deposits of Bhutan. Though no detailed work was carried out during last few years in the Siwalik, Damuda, Setikhola and Diuri segments, the information contained in these chapters are based on previous unpublished work, with marginal additions. On the other hand, the Baxa, the Shumar, the Thimpu and the Tethyan chapters present new data. The present work necessitated defining a few new formations, viz, the Jaishidanda, the Singhi, the Deshichiling and the quartzite. The first occurs as a tectonic scale below the Thimphu thrust sheet and the latter three form parts of the Tethyan succession developed over the Thimphu crystallines. The chapter on the granitic rocks provides new petrochemical and geochronological data, which are very useful in regional correlation. The synthesis chapter presents the stratigraphic column, attempts correlation of various formations of the Bhutan Himalaya with the better known formations of the other parts of the Himalaya and provides a broad structural and metamorphic set-up. The chapter on Geological History presents an evolutionary model. In such an attempt certain generalisations become unavoidable. Chapter on mineral resources briefly gives the grade and reserves of important mineral deposits of Bhutan.