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Macusanite occurrence, age, and composition, Macusani, Peru

May 1, 1970

Macusanite, originally believed to be a type of tektite because of its sculpture, is shown to be related to sillar of the Macusani region, Peru. K-Ar measurements establish identical Pliocene ages (4.2 m.y.) for macusanite and sillar and relate these deposits to the extensive ash flows of the southern Andes. These rocks are unique for glassy rocks in that lithium, boron, and arsenic contents are very high; cesium, rubidium, tellurium, fluorine, and tin are higher than normal; zinc, copper, chromium, and zirconium are lower than normal; and high-alumina minerals such as andalusite are present.

Citation Information

Publication Year 1970
Title Macusanite occurrence, age, and composition, Macusani, Peru
DOI 10.1130/0016-7606(1970)81[1539:MOAACM]2.0.CO;2
Authors Virgil E. Barnes, George Edwards, W. A. McLaughlin, Irving Friedman, Oiva Joensuu
Publication Type Article
Publication Subtype Journal Article
Series Title Bulletin of the Geological Society of America
Index ID 70226544
Record Source USGS Publications Warehouse