Vavilov seamount: a mildly alkaline Quaternary volcano in the Tyrrhenian basin
In: Marine Geology. Elsevier: Amsterdam. ISSN 0025-3227; e-ISSN 1872-6151, more
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| Keywords |
Aquatic sciences > Marine sciences > Geology > Marine geology
Chemical elements > Metals > Rare earths
Cycles > Chemical cycles > Geochemical cycle
Earth sciences > Geology > Petrology
Rocks > Igneous rocks > Volcanic rocks > Basalts > Alkali basalts
Topographic features > Submarine features > Seamounts
Volcanoes > Submarine volcanoes
MED, Tyrrhenian Sea, Vavilov Seamount [Marine Regions]
Marine/Coastal |
| Authors | | Top |
- Robin, C.
- Colantoni, P.
- Gennesseaux, M.
- Rehault, J.P.
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| Abstract |
Vavilov seamount emerges from the Central Tyrrhenian plain, at 3600 m depth, and reaches 684 m below sea level. Four dives in the Cyana submersible showed that this voluminous volcanic edifice (350-400 km3) can be divided into two parts: (1) from its base to 1500 m deep, a pile of thick submarine basaltic flows; and (2) an upper part, above 1500 m, consisting of smaller radial lava flows related to a major central volcano (Vavilov s.s.) and other minor vents aligned north-south. Although Vavilov is located at the supposed centre of oceanic accretion, the characteristics of its lavas strongly differ from those of the underlying crust. The basalts fall into the mildly alkaline series and are strongly enriched in light REE. Among the products of passive margin volcanism, they may be compared with intermediate basalts between the olivine-tholeiite of the continental flood basalts and the P-type oceanic basalts; in terms of oceanic volcanism, they are very close to Oceanic Island Basalts (OIB). Vavilov appears as a structure independent of the oceanic crust which supports it, and does not represent a ridge related to the oceanic accretion as one might suppose. (DBO) |
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