Comment on "A vestige of Earth's oldest ophiolite".
نویسنده
چکیده
The claim by Furnes et al. (Reports, 23 March 2007, p. 1704) that Greenland metavolcanic rocks require Paleoarchean sea-floor spreading is incompatible with their own data. The purported sheeted dikes have the composition of pyroxenitic komatiite and could not have fed the adjacent ferroandesitic pillow lavas. Neither type has ophiolitic analogs, and both are likely ensialic.
منابع مشابه
Comment on "A Vestige of Earth's Oldest Ophiolite"
Furnes et al. (1) reported that a sheeted-dike complex they identified within the ~3.8billion-year-old Isua supracrustal belt (ISB) in Greenland provides the oldest evidence of oceanic crustal accretion by spreading. However, they did not alert readers that the ISB contains supracrustal rocks and mafic dikes of different ages (2, 3). They also failed to demonstrate that the proposed components ...
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ورودعنوان ژورنال:
- Science
دوره 318 5851 شماره
صفحات -
تاریخ انتشار 2007