Mackey, K.G., 1999, Seismological studies in northeast Russia: East Lansing, Michigan, Michigan State University, Ph.D. dissertation, 349 p.
A seismicity catalog and associated list of seismic phases for larger events has been compiled for northeast Russia using published and unpublished data from the regional networks operating in eastern Russia (primarily Magadan, Yakutsk, and Amur), the western Alaska network, and international data files. The catalog contains more than 40,000 events and 110,000 arrival times. The resultant catalog is contaminated by industrial explosions, particularly in the Amur and central Magadan districts. The level of contamination is analyzed using the temporal distribution of events as anthropogenic events occur primarily during local day. Dramatic differences are observed between daytime and nighttime seismicity for the Amur district. Removal of anthropogenic sources allows easier identification of active faults. A seismicity trend was found to extend westward from the Seward Peninsula to northern Kamchatka, which is interpreted to define the northern boundary of a proposed Bering plate. Clockwise rotation of this plate about a Euler pole in northeast Chukotka is suggested to be driven by terrane accretion in southern Alaska and coupling with the Pacific plate. A preliminary crustal velocity model is developed by obtaining best fit travel time curves over 3 x 5 degree regions. The velocities obtained are generally in agreement with inferred tectonic regimes with high velocities in Precambrian platforms, low velocities in active rifts, and average velocities in Mesozoic terrane assembledges. The velocity model is then used to relocate larger regional events. Relocated events are used to develop a preliminary regional upper mantle tomographic model of northeast Russia.
Theses and Dissertations
