Virginia's Largest Earthquakes

2011. Aug. 23. Louisa County, central Virginia. The epicenter of Virginia's largest earthquake was 13 km south-southwest of Mineral, Virginia, in the central Virginia seismic zone. The shock is known as the Mineral earthquake. The moment magnitude was Mw 5.7, mbLg magnitude 6.3. The earthquake was felt throughout much of the eastern United States and southeastern Canada, possibly by more people than any other earthquake in U.S. history. It was the largest and most damaging earthquake in the eastern United States since the 1886 Charleston, South Carolina earthquake. Damage in the epicentral area represents Modified Mercalli intensity VIII, with many instances of broken and collapsed masonry walls and chimneys, as well as shifting of structures on their foundations. Significant damage occurred to structures at distances in excess of 130 km to the northeast in the Washington DC area. The rupture process was a complex reverse fault event, initiating at a depth of 8 km. The mainshock was followed by a prolific aftershock sequence that is still underway (August, 2014).

References:

Chapman, M.C., (2013). On the Rupture Process of the 23 August 2011 Virginia Earthquake, Bulletin of the Seismological Society of America, 103, 613-628.

Chapman, M.C., (2015) Magnitude, Recurrence Interval and Near-Source Ground Motion Modeling of the Mineral, Virginia Earthquake of August 23, 2011, in Horton, J.W., Jr., Chapman, M.C., and Green, R.A., eds., The 2011 Mineral, Virginia, Earthquake, and Its Significance for Seismic Hazards in Eastern North America: Geological Society of America Special Paper 509, doi:10.1130/2015.2509(21) (in press).

Horton, J.W., Jr., Chapman, M.C., and Green, R.A., (2015), The 2011 Mineral, Virginia,earthquake, and its significance for seismic hazards in eastern North America—Overview and synthesis, in Horton, J.W., Jr., Chapman, M.C., and Green, R.A., eds., The 2011 Mineral, Virginia, Earthquake, and Its Significance for Seismic Hazards in Eastern North America: Geological Society of America Special Paper 509, doi:10.1130/2015.2509(21) (in press).

The following is taken from SEISMICITY OF THE UNITED STATES, 1568-1989 (REVISED) by Carl W. Stover and Jerry L. Coffman (USGS Professional Paper 1527, 1993, pages 376-378)

1774. Feb. 21. Near Petersburg, Prince George County, Va. A sharp earthquake that was felt over much of Virginia displaced houses "considerably off their foundations" at Blandford and Petersburg. Although the shock was severe at Richmond and terrified residents about 80 km north of Richmond at Fredericksburg, it caused no damage at those towns. Several "smart shocks" were reported in parts of Virginia from Feb. 20th to the 22nd. The main tremor rang bells at Salem (now Winston-Salem), N.C. Magnitude 4.5 Mfa NUT. (Ref. 55, 167, 314.)

1833. Aug. 27. Central Virginia. A rather strong shock agitated walls of buildings at Lynchburg (west of Richmond, in southern Amherst County) and rattled windows violently. Fences along the road were shaken near the Louisa County Courthouse, northwest of Richmond. It was described as "severe" at Charlottesville, about 85 km northeast of Lynchburg. Two miners were killed in a panic caused by the tremor at a mine near Richmond. Ref. 179 suggests a MM intensity VI at the epicenter, although no damage was documented. Also felt in the District of Columbia, Maryland, and North Carolina. Magnitude 4.5 Mfa NUT. (Ref. 38, 167, 179.)

1852. Apr. 29. Near Wytheville, Wythe County, Va. A severe earthquake that was observed over a large area threw down a chimney near Wytheville, in southwest Virginia, and shook down tops of chimneys at Buckingham Courthouse, about 55 km south of Charlottesville. Houses were shaken violently at Staunton, about 65 km west of Charlottesville. A brick was shaken from a chimney as far south as Davie County, N.C. Also felt in the District of Columbia, Maryland, New York, Ohio, and Pennsylvania. Magnitude 4.9 Mfa NUT. (Ref. 38, 55, 86, 167, 508.)

1852. Nov. 2. Central Virginia. Chimney damage occurred at Buckingham, about 55 km south of Charlottesville. This earthquake was reported to be "quite strong" at Fredericksburg, Richmond, and Scottsville. At Scottsville, where every house in the village was shaken, water in the canal was "troubled," and boats were tossed to and fro. Magnitude 4.3 Mfa NUT. (Ref. 55, 167.)

1875. Dec. 23 (Dec. 22). Central Virginia. The highest intensities from this earthquake occurred mainly at towns near the James River waterfront in Goochland and Powhatan Counties, and in Louisa County. In Richmond (Henrico County), the most severe damage was sustained in the downtown business and residential areas adjacent to the James River or on islands in the river. Damage included bricks knocked from chimneys, fallen plaster, an overturned stove, and several broken windows. Waves "suddenly rose several feet" at the James River dock at Richmond, causing boats to "part their cables" and drift below the wharf. At Manakin, about 20 km west of Richmond, shingles were shaken from a roof and many lamps and chimneys were broken. Several small aftershocks were reported through Jan. 2, 1876. Felt from Baltimore, Md., to Greensboro, N.C., and from the Atlantic Coast westward to Greenbrier and White Sulphur Springs, W.Va. Magnitude 4.5 Mfa NUT. (Ref 55, 167, 365.)

1897. May 3. Southwest Virginia. This earthquake was most severe at Radford (about 65 km west of Roanoke), where a few chimneys were wrecked and plaster fell from walls. Chimneys were damaged at nearby Pulaski and at Roanoke. Felt in most of southwest Virginia and as far south as Winston-Salem, N.C. Magnitude 4.3 Mfa NUT. (Ref. 38, 55, 167, 272, 508.)

1897. May 31. Giles County, Va. This earthquake was the largest in intensity and areal extent in Virginia in historical times, [until the occurence of the August 23, 2011 Mineral, Virginia earthquake]. The earthquake had a maximum Modified Mercalli Intensity of VIII, and the area of maximum ground motion extended over an elliptical area-from near Lynchburg, Va., west to Bluefield, W.Va., and from Giles County south to Bristol, Tenn. The MM intensity VIII assigned to this earthquake is based on "many downed chimneys" and "changes in the flow of springs."

The shock was felt severely at Narrows, about 3 km west of Pearisburg. Here, the surface rolled in an undulating motion, water in springs became muddy, and water in some springs ceased to flow. The flow of water in springs also was disturbed in the area of Pearisburg, about 70 km west of Roanoke, and Sugar Run.

The shock was strong at Pearisburg, where walls of old brick houses were cracked and many chimneys were thrown down or badly damaged. Many chimneys also were shaken down at Bedford, Pulaski, Radford, and Roanoke, Va., and Bristol, Tenn.; many chimneys were damaged at Christiansburg, Dublin, Floyd, Houston, Lexington, Lynchburg, Rocky Mount, Salem, Tazewell, and Wytheville, Va.; Charlotte, Oxford, Raleigh, and Winston, N.C.; Knoxville, Tenn.; and Bluefield, W.Va. Felt from Georgia to Pennsylvania and from the Atlantic Coast westward to Indiana and Kentucky. Aftershocks continued through June 6, 1897. Magnitude 5.8 Mfa NUT. (Ref. 55, 167, 190, 525.)

1898. Feb. 5. Pulaski, Va. Bricks were thrown from chimneys, furniture was shifted in a few houses, and residents rushed into the streets at Pulaski, about 70 km southwest of Roanoke. Felt throughout southwest Virginia and south to Raleigh, N.C. (Ref. 38, 86, 167, 508.)

1907. Feb. 11. Near Arvonia, Buckingham County, Va. Chimneys were cracked at Ashby, about 20 km southeast of Arvonia, and a window was broken at a store at Buckingham, 25 km southwest of Arvonia. A "terrific" shock sent people rushing outdoors at Arvonia and displaced furniture. Felt strongly from Powhatan to Albemarle County. (Ref. 55, 167, 189.)

1918. Apr. 10 (Apr. 9). Luray, Page County, Va. In the Shenandoah Valley, at Luray, windows were broken and plaster was cracked severely. Ceilings of houses were cracked badly a few kilometers north of Luray, at Edinburg; windows were broken at Harrisonburg and Staunton, Va., and Washington, D.C. (at Georgetown University). In addition, a new spring formed in Page County, near Hamburg, almost in the middle of a road. A minor aftershock was reported in the area about 5 hours later. Also felt in Maryland, Pennsylvania, and West Virginia. (Ref. 38, 55, 186, 189, 272.)

1919. Sept. 6 (Sept. 5). Near Front Royal, Warren County, Va. This earthquake affected towns mainly in Warren and Rappahannock Counties. At Arco, in the Blue Ridge Mountains south of Front Royal, chimneys were damaged, plaster fell from walls, and springs and streams were muddied. Reports from the adjacent northern part of Rappahannock County state that similar shocks were felt and that streams were "rendered turbid." Also felt in parts of Maryland and West Virginia. Several aftershocks occurred. (Ref. 55, 187, 272.)

1929. Dec. 26 (Dec. 25). Charlottesville, Albemarle County, Va. A moderate tremor at Charlottesville shook bricks from chimneys in some places. Also felt in other parts of Albemarle County. (Ref. 38, 189.)

1959. Apr. 23. Giles County, Va. The earthquake was strongest in Giles County, at Eggleston and Pembroke. Residents there reported several damaged chimneys and articles shaken from shelves and walls. One chimney toppled at the Norfolk and Western Station in Eggleston. Also felt in West Virginia. Magnitude 3.8 Mfa DG. (Ref. 105, 349, 508.)

1975. Nov. 11. Southwest Virginia. Windows were broken in the Blacksburg area of Montgomery County, and plaster was cracked at Poplar Hill (south of Pearisburg, in Giles County). Also felt in Pulaski County. (Ref. 48, 349.)

1976. Sept. 13. Southwest Virginia. Bricks fell from chimneys and pictures fell from walls in Surry County at Mount Airy, N.C. At the nearby town of Toast, N.C., cracks formed in masonry and plaster. The earthquake was observed in many towns in North Carolina and Virginia and in a few towns in South Carolina and West Virginia. (Ref 49, 349.)