An Ancient Rift Complex and its relation to contemporary seismicity in the New Madrid Seismic Zone

Abstract

Gravity, magnetic, geologic, and seismicity data have been combined in a seismotectonic analysis of the New Madrid seismic zone. Previous studies have presented evidence for several rift zones in this area (Upper Mississippi embayment), including the Reelfoot rift, a late Precambrian‐early Paleozoic failed arm which extends N‐NE from the ancient continental margin. In this study, we propose that the northern terminus of the Reelfoot rift forms a rift complex which appears to correlate well with the seismicity in the area. This correlation suggests that faults associated with this rift complex are being reactivated in the contemporary stress field (ENE compression). If this interpretation is valid, it represents a seismotectonic model which can be used to predict the extent of future seismicity in the New Madrid seismic zone. The proposed rift complex also provides a coherent model for the tectonic development of this region of the North American midcontinent.

Localization of intraplate deformation through fluid-assisted faulting in the lower-crust: The Flinders Ranges, South Australia

“…The most spectacular examples are the Reelfoot Rift in the U.S. (associated with the M w 7.2-8.1 1811-1812 New Madrid earthquakes, see e.g. Braile et al, 1982), and the Kutch Rift in India (associated with the M w 7.7 1819 Rann of Kutch and M w 7.6 2001 Buhj earthquakessee Bilham, 1999 andRastogi et al, 2001, resp. ).…”

Late Cretaceous and Cenozoic Geology of the New Madrid Seismic Zone

“…The Mississippi embayment is a southwest plunging trough of late Cretaceous and Tertiary age (Stearns, 1957;Pryor, 1960). Formation of the Mississippi embayment has been attributed to the opening of the Gulf of Mexico and reactivation of the underlying late Precambrian to Cambrian Reelfoot rift (Burke and Dewey, 1973;Ervin and McGinnis, 1975;Kane et al, 1981;Braile et al, 1982). However, Cox and Van Arsdale (1997) argue that the Mississippi embayment formed as a consequence of plate tectonic drifting of the Mississippi Valley over the Bermuda hotspot in the Late Cretaceous.…”

Natural and Induced Seismicity in the Lake Erie-Lake Ontario Region: Reactivation of Ancient Faults with Little Neotectonic Displacement

“…The Western Ontario seismic zone is aligned with an aeromagnetic structure adjacent to and west of the Niagara-Pickering magnetic lineament and may be in a similar relation to the Coshocton zone as the Akron lineament. The association between seismicity and prominent Precambrian structures persists west of the study area, where the Anna seismic zone is spatially associated with the Grenville Front {e.g., Braile et al, 1982).…”

“…Then, we compare known structural features with seismicity patterns which are apparent in the revised earthquake data. Although correlation between structure and intracratonic earthquakes has been generally elusive, with improved resolution examples are now beginning to appear (e.g., Braile et al, 1982;Adams et al, 1991;Dawers and Seeber, 1991). We are particularly interested in characterizing the kind of structures that may be reactivated in the current tectonic stress regime (e.g., Sbar and Sykes, 1973;Zoback and Zoback, 1989) and to test the hypothesis that structures of any age may be pertinent to intracratonic seismogenesis.…”