Elsevier, Global and Planetary Change, (123), p. 249-268, 2014
DOI: 10.1016/j.gloplacha.2014.11.002
Elsevier, Global and Planetary Change, (122), p. 50-69, 2014
DOI: 10.1016/j.gloplacha.2014.07.021
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Dove Basin is situated in the south-central Scotia Sea, between Pirie and Bruce banks, and was formed during the development of the Scotia Arc. The basin has a roughly sigmoidal shape, with a prominent NNE-SSW elongated ridge located in its central part, the Dove Ridge, which is considered as an extinct spreading axis. A NE-SW elongated tectonic high, the Dove Seamount, is located in the north-eastern region of the basin, bounded by a normal fault dipping to the southeast. Dredged rocks and geophysical data were collected during the SCAN2004 and SCAN2008 cruises. Dredged samples were recovered from three positive features in the center of the basin, two from Dove Ridge, and one from Dove Seamount. Igneous rocks along the Dove Ridge are mainly tholeiitic basalts, derived from asthenospheric upper mantle within an extensional supra-subduction back-arc tectonic setting, which evolved over time from back-arc basin basalts (BABB) toward Mid Oceanic Ridge Basalts (MORBs). Altered olivine-bearing fine- and medium-grained basaltic rocks were also dredged from Dove Ridge and the seamount, together with minor oceanic island arc basalts and basaltic andesites. The mantle source was affected, up to early Miocene times, by a subducted oceanic slab related to an arc to the east, with Dove Basin forming in a back-arc position. Minor alkaline oceanic island basalts dredged at the seamount might represent a final extensional stage, genetically related with the dying Dove Ridge volcanism or, less probably, to a later, late Miocene-Pliocene extensional stage, producing incipient volcanism deriving from a deeper mantle source.