Dear all,
I concur with Dave Waters and others. The silicate-
cdominated rock described as "made up of calcite ( 30%)
, and wollastonite+diopside+grossular+ quartz (70%)"
is in my view certainly a calc-silicate. It has a similar
mineralogy (apart from the absence of scapolite) to calc-
silicates described in my papers of the ealry-mid 1990s
(e.g. Harley & Buick, JPetrol 1992; Harley et al.,
Precamb Res, 1994; Ftizsimons & Harley, J Met Geol
1994).
I would be very hesitant to immediately label such a rock
as a skarn, however, as that suggests to the wider world
a large degree of metasomatism. Whilst metasomatism
may have occurred, it is in no way implicit in the actual
assemblage itself, as the initial bulk rock X may have
been that of a marl, for example.
Regards,
Simon Harley
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Simon Harley FRSE
Professor of Lower Crustal Processes
Assistant Head of School (Geology & Geophysics)
School of Geosciences
University of Edinburgh
Kings Buildings, West Mains Road
EDINBURGH, EH9 3JW, SCOTLAND
phone: (44) 0131 650 4839
fax: (44) 0131 668 3184
email: [log in to unmask]
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