New Madrid Seismic Zone: a test case for naturally induced seismicity

Conference · Thu Sep 01 00:00:00 EDT 1983 · Am. Assoc. Pet. Geol., Bull.; (United States)

OSTI ID:6625906

Nava, S J

Induced seismicity caused by man-made events, such as the filling of reservoirs has been well documented. In contrast, naturally induced seismicity has received little attention. It has been shown that a fluctuation of as little as several bars can trigger reservoir induced earthquakes. Naturally occurring phenomena generate similar fluctuations and could trigger earthquakes where the faults in ambient stress field are suitably oriented and close to failure. The New Madrid Seismic Zone (NMSZ) presents an ideal test case for the study of naturally induced seismicity. The ideal data set for a study of triggering effects must contain a statistically significant number of events, a constant accumulated strain, and a limited focal region. New Madrid earthquakes are well documented from 1974 to the present, down to a magnitude approx. 1.8. They lie in a distinct fault pattern and occur as a reaction to the regional stress regime. A statistical correlation was made between the earthquakes and a variety of different types of loads, to see if New Madrid seismicity could be triggered by natural fluctuations. The types of triggers investigated ranged from solid earth tides to variations in barometric pressure, rainfall, and stages of the Mississippi River. This analysis becomes complex because each factor investigated creates individual stresses, as well as having imbedded in it a reaction to other factors.

• Research Organization: Memphis State Univ., TN
• OSTI ID: 6625906
• Report Number(s): CONF-8310301-
• Journal Information: Am. Assoc. Pet. Geol., Bull.; (United States), Vol. 67:9; Conference: American Association of Petroleum Geologists eastern section meeting, Carbondale, IL, USA, 3 Oct 1983
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
EARTHQUAKES
NATURAL OCCURRENCE
RIFT ZONES
SEISMICITY
ARKANSAS
CORRELATIONS
ILLINOIS
KENTUCKY
MISSOURI
SEISMIC DETECTION
TENNESSEE
DETECTION
FEDERAL REGION IV
FEDERAL REGION V
FEDERAL REGION VI
FEDERAL REGION VII
GEOLOGIC STRUCTURES
NORTH AMERICA
SEISMIC EVENTS
USA
580201* - Geophysics- Seismology & Tectonics- (1980-1989)