The massif is oriented north–south. The eastern slope, although it is sometimes considered to extend to the Galibier and Télégraphe passes and therefore including the Arves massif, is limited by the Arvan and Ferrand rivers.[1] The Eau d'Olle rivers and therefore the Belledonne range to the west, and Romanche and the Écrins massif to the south form its other geographical limits.
The Grandes Rousses massif is a crystalline geological formation similar to the nearby Belledonne range. It forms a long, north–south oriented chain, appearing as a northern extension of the Écrins massif. The massif is characterized by several north–south bands, many of which are separated by structural depressions from the late Hercynian period.[2] These depressions, likely synclines or grabens, are filled with coal-bearing lands, some of which show Triassic deposits lying at 90 degrees.
History
The Grandes Rousses massif is dotted with numerous abandoned mines. The most notable site is Brandes-en-Oisans, a mining village that operated silver mines from the 12th to the 14th century.[3] Located in the commune of Huez at an altitude of over 1,800 meters, Brandes-en-Oisans once had up to 80 buildings centered around a church.[4] Although of moderate importance on a European scale, Brandes was of significant importance to the Dauphiné region.
