Richard I. Grauch, 1972. "Preliminary Report of a Late(?) Paleozoic Metamorphic Event in the Venezuelan Andes", Studies in Earth and Space Sciences, R. Shagam, R. B. Hargraves, W. J. Morgan, F. B. Van Houten, C. A. Burk, H. D. Holland, L. C. Hollister
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Recent studies in the central Venezuelan Andes suggest that a major episode of regional metamorphism took place in late Paleozoic time, affecting fossiliferous Permo-Carboniferous rocks and previously metamorphosed Precambrian(?) rocks.
Staurolite zones (±1 to 2 km wide) encompassing andalusite, kyanite, and sillimanite isograds spaced at approximately 100-m intervals have been mapped on a regional scale. One, possibly two, of these zones may truncate an earlier sillimanite isograd. On the basis of thin-section studies, mineral paragenesis within one of the staurolite zones appears to be as follows: (a) staurolite; (b) idioblastic andalusite; (c) andalusite → kyanite, staurolite; (d) andalusite → sillimanite, kyanite → sillimanite or fibrolite; (e) staurolite pseudomorphed by muscovite and sillimanite or fibrolite.