While most of the Briançonnais zone of the Western Alps has been through blueschist facies conditions, it is not always easy to find good rocks to look at. Some of the best (and most accessible) metagabbros are found as pebbles in the Gul river downstream of Chateau-Queyras; the gabbros here are only partly transofrmed into blueschist, such that the glaucophane forming reaction (at the expense of hornblende) can be seen in the rocks.
Bruand, E., Nicollet, C., Goncalves, P., Schwartz, S., Chamorro-Perez, E., 2010. Petrology of metagabbros and Schistes Lustrés through the Queyras accretionary wedge (Western Alps), EGU General Assembly 2010, Vienna, p. 11983.
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