title: Crustal structure of the northeastern United States: contrasts between grenville and appalachian provinces.
abstract: Average crustal models for the northeastern United States are computed on the basis of the travel times of P and S waves from regional earthquakes. The Precambrian Grenville Province in New York State has a relatively homogeneous crust. The Paleozoic New England Appalachians have a well-defined, two-layer crust that is slightly thicker and shows a high-velocity lower layer relative to the Grenville. A time-term analysis based on P(n) data (waves refracted from the Moho) shows that a relatively thick or low-velocity crust parallels northeast-trending geologic structures in central New England. The observed differences between the two orogenic belts may reflect contrasts in their tectonic evolution.
authors.forename: S R
authors.initials: SR
authors.lastname: Taylor
authors.forename: M N
authors.initials: MN
authors.lastname: Toksöz
authors.forename: M P
authors.initials: MP
authors.lastname: Chaplin