Charlotte Keen is an outstanding young marine geophysicist. She undertakes innovative and difficult experiments at sea, in the hostile regions of the North Atlantic and eastern Arctic, and interprets the results with excellent theoretical insight. She showed that the mantle beneath the Mid-Atlantic Ridge is anisotropic, and that the oceanic crust developed in a relatively short time. She showed that Bafin Bay possesses an oceanic crust; she showed that the transition from continent to ocean off the rifted margin of eastern Canada is narrow, and the transition zone anomalous. Her work led to the recognition of hitherto unknown magnetic lineations in Baffin Bay, the Quiet Zone of the northwest Atlantic Ocean and the Newfoundland Basin. Her influence saw that ocean bottom seismometers were developed and used to study the transition from continent to ocean. She is one of the pioneers of deep marine seismic reflection studies of rifted continental margins and was instrumental in the initiation of LITHOPROBE, Canada's National Program of 3-dimensional studies of the earth's crust and upper mantle. She influences the work of all her colleagues, and has guided many students. She is the recipient of many honours internationally, including the Woolard Award of the Geological Society of America and the Wilson Medal of the Canadian Geographical Union.