Frost, B. Ronald; Beard, James S.; McCaig, Andrew; Condliffe, Eric (2008): The formation of micro-rodingites from IODP hole U1309D; key to understanding the process of serpentinization. Oxford University Press, Oxford, United Kingdom, Journal of Petrology, 49 (9), 1579-1588, georefid:2009-006638

Olivine-rich troctolites of Integrated Ocean Drilling Program hole U1309D contain abundant veins along which the olivine has been serpentinized. Where the serpentinite veins cut plagioclase the plagioclase has been altered to prehnite and in many places the prehnite in the core of the vein has been altered to grossular. We show that these Ca-rich assemblages, which we call micro-rodingites, need not have formed by Ca-metasomatism. Instead the micro-rodingites could have occurred during serpentinization as a nearly closed-system process (apart from the addition of water and release of H (sub 2) and Na (super +) ). We argue that in these rocks the alteration of plagioclase occurred as a result of the very low silica activity that accompanies serpentinization. The reaction of plagioclase to prehnite and prehnite to grossular provided a source of SiO (sub 2) that allowed olivine to hydrate to serpentine without producing much brucite. Excess Al (sub 2) O (sub 3) produced by the alteration of plagioclase reacted with serpentine to produce chlorite and additional SiO (sub 2) .
West: -42.0700 East: -42.0600 North: 30.1100 South: 30.1000
Expedition: 304
Site: 304-U1309
Expedition: 305
Site: 305-U1309
Data access:
Provider: SEDIS Publication Catalogue
Data set link: (c.f. for more detailed metadata)
This metadata in ISO19139 XML format