[2] He has contributed articles to professional journals and is a fellow of the Geological Society of America (Councillor, 1985–88, 1990–93; President, 1991–92); the American Association for the Advancement of Science (AAAS), the American Academy of Arts and Sciences, the Mineralogical Society of America (Council, 1974–77;Pres., 1975–76).
[3] Zen has been active in programs to bring geological knowledge to the general public.
[3] Zen has worked primarily in the northern Appalachians, especially on paleogeographic reconstructions and the origins of exotic terranes in New England.
John McPhee once remarked that Zen "is approximately as exotic as the rock he studies.
He has also been honored for outstanding contributions to public understanding of geology (American Geological Institute, 1994) and with the Thomas Jefferson Medal, Virginia Museum of Natural History, 1995.