Preliminary report of the distribution of intensities for the Kentucky earthquake of July 27, 1980

Reagor, B.G.; Stover, C.W.; Hopper, Margaret G.

doi:10.3133/ofr81198

Cited by 3 publications

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Maysville is located on a bearing of N22uE from the epicenter; thus a right-lateral strike-slip fault striking N30uE would suggest Maysville could potentially experience elevated ground motions due to directivity effects. Herrmann et al (1982) and Reagor et al (1981) also pointed out that the location and magnitude of the Sharpsburg earthquake were unexpected for an area with such low seismic activity; no equivalent-magnitude earthquake has been reported within 200 km.…”

Section: Seismicitymentioning

confidence: 99%

The Role of Local Soil-Induced Amplification in the 27 July 1980 Northeastern Kentucky Earthquake

Woolery

Lin

Wang

et al. 2008

Environmental and Engineering Geoscience

View full text Add to dashboard Cite

Amplification of earthquake ground motions by nearsurface soil deposits was believed to have occurred in Maysville, Kentucky, U.S.A. during the northeast Kentucky (Sharpsburg) earthquake (m b,Lg 5.3) of July 27, 1980. The city of Maysville, founded on approximately 30 m of Late Quaternary Ohio River flood plain alluvium, was 52 km from the epicenter, but experienced equivalent or higher Modified Mercalli Intensity (MMI) VII, compared with the epicentral area of the earthquake (i.e., MMI VI-VII). In this study, dynamic soil properties were obtained at 10 sites in Maysville using seismic P-wave and S-wave (SHmode) refraction and reflection methods. Synthetically generated composite time histories and limited geotechnical information, along with the measured dynamic properties, were used to perform one-dimensional linear-equivalent amplification analyses. The results indicated the soils generated ground-motion amplification factors between 3.0 and 6.0 and at a frequency range between 2.0 and 5.0 Hz (0.2 to 0.5 s). The building damage in Maysville from the Sharpsburg earthquake was predominantly found in one-to threestory masonry structures. The estimated fundamental period for one-to three-story masonry buildings is approximately 0.11 to 0.26 s (3.8 to 9 Hz). These correlations suggest the elevated ground motion intensity in Maysville can be accounted for by near-surface soil-amplification effects and resonance of the ground motion by the buildings (i.e., double resonance).

show abstract

Section: Seismicitymentioning

confidence: 99%

The Role of Local Soil-Induced Amplification in the 27 July 1980 Northeastern Kentucky Earthquake

Woolery

Lin

Wang

et al. 2008

Environmental and Engineering Geoscience

View full text Add to dashboard Cite

show abstract

The Sharpsburg, Kentucky, earthquake of 27 July 1980

Herrmann

Langston

Zollweg

1982

Bulletin of the Seismological Society of America

View full text Add to dashboard Cite

The Sharpsburg, Kentucky, earthquake was the second largest earthquake to have occurred in the United States, east of the Continental Divide, in the past 20 yr, having a seismic moment of 4.1 × 1023 dyne-cm. A surface-wave focal mechanism study defines a nodal plane striking N30°E, dipping 50°SE, and a nearly vertical nodal plane striking N60°W. P-wave first motion data indicate right-lateral motion on the nodal plane striking N30°E, with the pressure axes oriented east-west. These angles can be varied by ±10° without affecting the fit to the surface-wave data. The surface-wave solution is reinforced by a modeling of long-period seismograms at regional distances. The P, pP, and sP polarities and amplitudes from the short-period vertical component array stack at NORSAR are used together with six unambiguous short-period P-wave first motions recorded in North America to test whether it is possible to constrain focal mechanism solutions with such data. These solutions are compatible with the surface-wave solution. Waveform modeling of the NORSAR data suggests a source pulse duration of 1.0 sec and constrains the depth to 12.0 km. To match mb estimates from NORSAR and Canadian stations, t*, for teleseismic P, must be 0.7 and 0.5, respectively, when the synthetics are scaled using the surface-wave seismic moment. In spite of extensive coverage of the epicentral zone, fewer than 70 aftershocks were recorded. The largest aftershock and an mbLg = 2.2. Aftershock locations suggest that the nodal plane striking N30°E is the fault plane. An aftershock area of 30 to 50 km2 implies a stress drop of 2.8 to 6 bars and a dislocation of 2.0 to 3.4 cm. Because of the variety of studies performed, this earthquake is presently the best-studied eastern North American seismic event with well-constrained estimates of focal depth, focal mechanism and seismic moment, and indications of the duration of the source time function and upper mantle P-wave t*.

show abstract

Ground motion values obtained for the 27 July 1980 Sharpsburg, Kentucky, earthquake

Street

1982

Bulletin of the Seismological Society of America

View full text Add to dashboard Cite

Free-field, vector-sum peak particle velocity recordings of the 27 July 1980 Sharpsburg, Kentucky, earthquake result in the following equations log 10 V R ( 1 Hz ) ( cm/sec ) = − 3.56 + 1.0 m b L g − 1.0 log 1 0 R ( km ) and log 10 V R ( 5 Hz ) ( cm/sec ) = − 3.56 + 1.0 m b L g − 1.0 log 1 0 R ( km ) where VR(1 Hz) refers to the resultant vector-sum peak particle velocity at 1 Hz, VR(5 Hz) refers to the resultant vector-sum peak particle velocity at 5 Hz, mbLg is the 1-Hz Lg magnitude commonly used in the Eastern United States, and R is the epicentral distance in kilometers. These equations are intended for the prediction of the maximum particle velocity associated with Lg waves in the Eastern United States in the far-field region of an earthquake, on competent foundation materials.

show abstract

Preliminary report of the distribution of intensities for the Kentucky earthquake of July 27, 1980

Cited by 3 publications

References 0 publications

The Role of Local Soil-Induced Amplification in the 27 July 1980 Northeastern Kentucky Earthquake

The Role of Local Soil-Induced Amplification in the 27 July 1980 Northeastern Kentucky Earthquake

The Sharpsburg, Kentucky, earthquake of 27 July 1980

Ground motion values obtained for the 27 July 1980 Sharpsburg, Kentucky, earthquake

Contact Info

Product

Resources

About