G. Marshall Kay

G. Marshall Kay


1904 - 1975

G. Marshall Kay was born in Paisley, Ontario, in 1904, but grew up mainly in Iowa City, Iowa. His father, George Frederick Kay, a distinguished geologist, was professor of Pleistocene geology at the University of Iowa, as well as the state geologist of Iowa. Marshall received a B.S. (1924) from the University of Iowa and a Ph.D. from Columbia University (1929). Following his graduate studies, he lectured at Barnard College (1929-1931). Subsequently, he became an instructor at Columbia University (1931), where he attained the rank of professor (1944) and ultimately was appointed Newberry professor of geology (1967). Kay’s specialty was Paleozoic stratigraphy; he viewed the regional distribution of strata in time and space as records of geosynclinal and continental evolution. He had an extraordinary memory that was developed through memorization exercises with railroad timetables and baseball statistics. Throughout his career he received multiple awards and honors, including, most noteworthy, the prestigious Penrose Medal (1971).


His early research (1930’s) on the Hounsfield metabentonite (metamorphosed ash) eventually led to more realistic portrayals of Appalachian (and global mountain belt) paleogeography and significantly, of how continents evolve. Kay demonstrated that the Hounsfield extended from New York State to the Midwest and that its source was in the southeastern Appalachians, upon what was traditionally viewed as a Precambrian crystalline borderland. From these studies he developed the idea that volcanic rocks in the Appalachians were products of Paleozoic eugeosynclines, or island arcs, and that these arcs, rather than an ancient borderland, rimmed North America. His paper “Paleogeographic and palinspastic maps”(1945), summarized some of these concepts and very likely had a strong influence on fellow ‘Pioneer of Appalachian Geology’, Harold Williams. Kay’s substitution of relatively young magmatic arcs for ancient borderlands helped to firmly establish the hypothesis that the North American continent grew outward through time instead of being a fixed, stagnant mass. This concept was an important step towards the realization of plate tectonics. Through his stratigraphic studies he also distinguished many other forms of geosynclines and these studies culminated in the publication of his famous Geological Society of America Memoir 48, North American Geosynclines (1951).


The advent of plate tectonics in the late 1960’s confirmed Kay’s ideas of magmatic arcs at the margins of continents and illuminated the tectonic significance of his various types of geosynclines. He fully embraced this new tectonic standard and in 1967 Kay convened the famous Gander Conference, an ‘International Conference on Stratigraphy and Structure Bearing on the Origin of North Atlantic Ocean”; he edited an encapsulation of the conference, North Atlantic – Geology and Continental Drift (1969). Marshall remained active in field research until his passing in 1975.

Head of Border Trail Between US and Canada

Maine Chapter of the International Appalachian Trail • 27 Blake Street * Presque Isle, ME 04769