Crustal Thickness Variation in the Northern Appalachian Mountains: Implications for the Geometry of 3-D Tectonic Boundaries Within the Crust
Abstract
Teleseismic receiver functions were calculated to image the Moho geometry in the northern Appalachian Mountains in order to explore crustal thickness variations and possible linkages with tectonic units. Waveforms from 1995 to 2016 were analyzed for a total of ~ 200 broadband seismic stations, yielding a well-distributed data set with high lateral resolution. Consistent P-to-S phases converted at the Moho can be clearly observed. The Moho depth increases from the coastal plain northwestward to the Appalachian Plateau, with a sharp east-west gradient in southern New England. A distinct subrectangular downward deflection of the Moho is imaged in northern New Hampshire and western Maine. There is a spatial correlation observed between Moho depth variations and the NE-SW trending Appalachian orogenic strike. Variations of crustal thickness along and across the orogenic strike provide insights into the formation and modification of the crust during and after the major Appalachian orogenic events.
Publication Title
Geophysical Research Letters
Recommended Citation
Li, C., Gao, H., Williams, M., & Levin, V. (2018). Crustal Thickness Variation in the Northern Appalachian Mountains: Implications for the Geometry of 3-D Tectonic Boundaries Within the Crust. Geophysical Research Letters, 45 (12), 6061-6070. https://doi.org/10.1029/2018GL078777