New Madrid Seismotectonic Program. Final report

Technical Report · Sun Jun 01 04:00:00 EDT 1986

OSTI ID:5734692

Buschbach, T C

The New Madrid Seismotectonic Program was a large-scale multidisciplinary effort that was designed to define the structural setting and tectonic history of the New Madrid area in order to realistically evaluate earthquake risks in the siting of nuclear facilities. The tectonic model proposed to explain the New Madrid seismicity is the ''zone of weakness'' model, which suggests that an ancient rift complex formed a zone of weakness in the earth's crust along which regional stresses are relieved. The Reelfoot Rift portion of the proposed rift complex is currently seismically active, and it must be considered capable and likely to be exposed to large-magnitude earthquakes in the future. Earthquakes that occur in the Wabash Valley area are less abundant and generally have deeper hypocenters than earthquakes in the New Madrid area. The area of the Southern Indiana Arm must be considered to have seismic risk, although a lesser extent than the Reelfoot Rift. The east-west trending Rough Creek Graben is practically aseismic, probably in large part due to its orientation in the current stress field. The northwest-trending St. Louis Arm of the proposed rift complex includes a pattern of seismicity that extends from southern Illinois along the Mississippi River. This arm must be considered to have seismic risk, but because of the lack of development of a graben associated with the arm and the orientation of the arm in the current stress field, the risk appears to be less than in the Reelfoot Rift portion of the rift complex.

• Research Organization: Saint Louis Univ., MO (USA)
• OSTI ID: 5734692
• Report Number(s): NUREG/CR-4632; ON: TI86901521
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
220501 -- Nuclear Reactor Technology-- Environmental Aspects-- Siting
58 GEOSCIENCES
580201* -- Geophysics-- Seismology & Tectonics-- (1980-1989)
ARKANSAS
EARTHQUAKES
FEDERAL REGION IV
FEDERAL REGION V
FEDERAL REGION VI
FEDERAL REGION VII
GEOLOGIC FAULTS
GEOLOGIC FRACTURES
GEOLOGIC STRUCTURES
ILLINOIS
INDIANA
KENTUCKY
MISSOURI
NORTH AMERICA
RIFT ZONES
SEISMIC EVENTS
SEISMICITY
TECTONICS
TENNESSEE
USA