1. Engineering geology of the Northeast corridor, Washington, D.C., to Boston, Massachusetts earthquake epicenters, geothermal gradients, and excavations and borings / [cartographic material] Yale Public content 1967. 2012-10-08T20:05:02Z. 2021-05-21T21:35:05Z. Geological Survey (U.S.). U.S. Geological Survey. English. Public. Northeastern States.