Lateral Variation of Crustal Lg Attenuation in Eastern North America.

ABSTRACT: We perform Q _Lg tomography for the northeastern part of North America. Vertical broadband seismograms of 473 crustal earthquakes recorded by 302 stations are processed to extract the Lg amplitude spectra. Tomographic inversions are independently conducted at 58 discrete frequencies distributed evenly in log space between 0.1 and 20.0 Hz. This relatively large dataset with good ray coverage allows us to image lateral variation of the crustal attenuation over the region. Obtained Q _Lg maps at broadband and individual frequencies provide new insights into the crustal attenuation of the region and its relationship to geological structures and past tectonic activity in the area. The Q _Lg shows more uniform values over the older, colder, and drier Canadian Shield

SUBMITTER: Zhao LF 

PROVIDER: S-EPMC5940689 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature