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Regional Seismic Hazard Earthquake Locations

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Regional Seismic Hazard Earthquake Locations OPEN- FILE REPORT 2008–1221 U.S. DEPARTMENT OF THE INTERIOR U.S. GEOLOGICAL SURVEY Prepared in cooperation with the Ohio Department of Natural Resources, Earthquakes in Ohio and Vicinity 1776–2007 Division of Geological Survey SEISMIC HAZARD Compiled by Richard L. Dart¹ and Michael C. Hansen² Some level of seismic hazard from earthquake ground shaking exists in every part of the United Regional Seismic Hazard States. The severity of the ground shaking, however, can vary greatly from place to place. Seismic 86° 84° 82° 80° 2008 Earthquake Locations hazard maps, like the one shown at right, illustrate this variation. The risk level shown on seismic GEORGIAN BAY 85°W 84°W 83°W 82°W 81°W 80°W hazard maps is based on a variety of factors, such as earthquake rate of occurrence, magnitude, This map summarizes more than 200 years of Ohio earthquake history. The history of Ohio Leslie Stockbridge Harper Woods extent of affected area, strength and pattern of ground shaking, and geologic setting. BellevueOlivet Whitmore Lake OAKLANDNorthville MACOMB BARRY EATON INGHAM LIVINGSTON Highland Park Grosse Pointe Farms earthquakes was derived from letters, journals, diaries, newspaper accounts, scholarly articles and, Salem Hamtramck Worden Grosse Pointe Rives Junction Grosse Pointe Park 1857 beginning in the early twentieth century, instrumental recordings (seismograms). All historical Springport Plymouth Livonia WAYNE P Seismic hazard maps are tools for determining acceptable risk. As such, they are critical in LAKE HURON BATTLE CREEK Detroit E Dexter Westland Dearborn (pre-instrumental) earthquakes that were large enough to be felt have been located based on anecdotal Battle Creek Chelsea Barton HillsDixboro Canton NNS helping to save lives and preserve property. They provide information essential to the creation and Brownlee Park JACKSON Ann Arbor Cherry Hill Wayne Melvindale accounts. Some of these events caused damage to buildings and their contents. The more recent Marshall A O updating of seismic design provisions for local building codes. Because most buildings and other Parma Denton Ecorse D 44° 44° Jackson Grass Lake ANN ARBOR Ypsilanti Taylor HI Albion Eastlawn A Y Lawrence Park widespread use of seismographs has allowed many small earthquakes, previously undetected, to be CALHOUN Michigan Center Romulus Southgate ONTARIO N structures in the central United States were not built to withstand severe ground shaking, damage Spring Arbor Belleville A L Erie TORONTO WASHTENAW DETROITRoulo O recorded and accurately located. The seismicity map (right) shows the historically located and Vandercook Lake Riverview C V could be catastrophic in the event of a powerful earthquake. The work of seismic-hazard scientists Concord Napoleon Saline New Boston ERIE ERIE JACKSON Stony Creek A Homer Manchester Bridgewater WoodhavenTrenton A ONTARIO instrumentally recorded earthquakes in and near Ohio. Whittaker S N and engineers provides the groundwork for future urban environments that will be safer if large Clarklake Willow Grosse Ile U Avonia Burlington Brooklyn Waltz Flat Rock I Tekonsha Hanover Lake City Fairview magnitude earthquakes occur. Additional applications of the information derived from these maps Milan A Oakville Rockwood McKean Cement City Clinton E North SpringfieldGirard 42°N Union City Carleton East Rockwood I LAKE ONTARIO Litchfield South Rockwood R include insurance-rates setting, estimating hillside stability and landslide potential, and estimating Milleville Beach Platea MICHIGAN E Conneaut EARTHQUAKES Devils LakeOnsted Tecumseh Maybee assistance funds needed for earthquake education and preparedness. FLINT Estral Beach E 42°N Jonesville Addison Britton K NIAGARA-ATTICA SEISMIC ZONE North Adams Manitou Beach Dundee ASHTABULA North Kingsville Albion Allen Woodland BeachStony Point A LAKE 2001 Edinboro Coldwater Quincy L Edgewood Ashtabula Kelloggsville LANSING Earthquakes occur as a result of slip on faults, typically many kilometers underground, and most Hillsdale Ida Monroe Geneva-on-the-Lake Seismic hazard maps are an estimation of how the ground in a particular area is likely to respond BUFFALO BRANCH LENAWEE Adrian West Monroe 2006 Osseo Deerfield North Madison Saybrook Cambridge Springs GRAND RAPIDS earthquakes occur along the boundaries of moving crustal plates. Ohio is within the North American Bronson South Monroe Springboro to local and regional earthquakes. They differ from isoseismal maps in that they are probability 1947 Hudson Clayton 2003 Geneva 1987 Venango Reading plate, far away from any plate boundaries. Usually it is not possible to determine exactly which fault Blissfield MONROE North Perry Madison Austinburg Conneautville Woodcock maps. They illustrate what shaking levels are likely, or example a 2 percent probability that it will HILLSDALE Luna Pier 1993 Perry Pierpont NEW Jasper Jefferson Saegertown DETROIT causes an earthquake. Accordingly, the most direct indicators of earthquake hazards are the earth- Temperance Grand River be worse over a stated time period (for example, 50 years). MICHIGANMontgomery Frontier Weston Painesville Eagleville Fairport Harbor LECO CRAWFORD Blooming Valley MICHIGAN LAKE YORK quakes themselves, not the faults on which they occur nor the motions of crustal plates. Camden Lambertville Mentor-on-the-Lake ACEO Dorset Orland Fremont Waldron AN LinesvilleFredericksburgMeadville MICMorenciHIG MetamoraBerkey 1953Sylvania Mentor Rock Creek Lyons Harbor View LakelineEastlake Roaming Shores INDIANA Silica Kirtland Hills The seismic energy released during an earthquake radiates in all directions as waves. As the seismic LAKE ERIE Pioneer Fayette Willowick Andover Conneaut Lake 42° 42° Alvordton Oakshade LUCAS Toledo Put-in-Bay 1991 1986Montville Before earthquakes were instrumentally recorded, estimated locations were typically within a few OHIO Ottawa Hills Oregon CUYAHOGA LOOCWickliffe Kirtland New Lyme Station Pymatuning waves move upward they are amplified or de-amplified as they travel through the sediment layers Kunkle UTLO OTTAWA Euclid STEUBEN Angola Holland Waite Hill Chardon Pymatuning tens of kilometers of the actual epicenters. Even with modern instrumentation, however, earthquake LAGRANGE Metz Holiday City FULTON Rossford Williston 1943 Simons Reservoir Cochranton near the ground surface. Seismic wave amplification or de-amplification can significantly affect the Catawba Island ERIE Mayfield Aquilla Orwell Montpelier West Unity SwantonTOLEDO Walbridge Bratenahl Reservoir Stroh Pleasant Lake Delta Maumee Millbury Chesterland East Claridon 1998 NORTHEAST OHIO locations within the Earth are only approximations, usually within several kilometers of their actual South Euclid Lyndhurst way the ground shakes during an earthquake. TOLEDO Edon Wauseon Elliston Lakeside LORAIN CLEVELAND Jamestown CLEVELAND WILLIAMS Lime City Marblehead Avon Lake CLEO Gates Mills SEISMIC ZONE HudsonAshley Hamilton Perrysburg Genoa Port Clinton GEAUGA North BloomfieldGustavus Sheakleyville locations. However, in areas where networks of closely spaced recording instruments exist earth- Blakeslee Archbold Whitehouse Stony Ridge Oak Harbor Sheffield LakeBay Village Lakewood Beachwood Burton Kinsman Stryker Waterville Gypsum Woodmere Middlefield New Lebanon Neapolis Westlake Elmore Bay View Lorain Avon North RandallOrange South Russell Greenville quakes can be more accurately located. Despite location uncertainties earthquakes have occurred in DE KALB Bryan Haskins Sandusky LORAIN Brooklyn An additional factor in determining how the ground will respond during an earthquake is the rate Gerald Luckey Woodville Bay Bridge Fairview Park Linndale Bentleyville Mecca MERCER Edgerton Liberty Center Fairview Lanes Vermilion Vincent Parma Bainbridge Welshfield West Farmington FT WAYNE most parts of Ohio during the last 200 years. Corunna Waterloo Butler Lindsey Sheffield Brook Park Bedford Solon Parkman Stoneboro of shaking. As a seismic wave passes a given map location, the ground will vibrate. If ground Grand RapidsTontogany Pemberville Castalia Amherst Seven Hills Oakwood Orangeville Sandy Lake Napoleon BGSO Gibsonburg Vickery Huron Elyria West ViewBerea Valley View Cortland Fredonia AKRON Farmer Ney Bowling Green South Amherst Northfield vibration (oscillation) is rapid (short-period motion), the seismic wave’s energy will dissipate quickly. NOBLE McClure Shinrock Champion PENNSYLVANIA Auburn Okolona Fremont Parkertown Laporte BrecksvilleMacedonia Aurora Hiram TRUMBULL Clark Jackson Center Garrett Newville Weston Helena Berlin Heights Brentwood Lake North Eaton Strongsville Magnitude (M) is the most common measure of an earthquake’s size. An earthquake’s magnitude SANDUSKYBallville Twinsburg Mantua Garrettsville Yankee Lake Conversely, if the ground vibration is slow (long-period motion), the wave’s energy will dissipate less Jewell Florida Malinta Portage Bradner Kimball Columbia Station North Royalton WARREN Saint Joe Clyde Milan Oberlin 2007 Brookfield Center reflects the total energy released as seismic waves. There are several methods to measure Brunersburg Rudolph Wayne ELYRIAGrafton Boston Heights Warren SharonSHARON Mercer Laotto Hicksville Sherwood Custar Bellevue Kipton Streetsboro Windham rapidly. Long-period waves propagate farther and retain their energy over longer distances than do Spencerville Defiance HENRY Risingsun Burgoon Collins Hudson Leavittsburg Farrell Green Springs Wakeman Lagrange Valley CityBrunswick Richfield Bolindale Wheatland earthquake magnitude. The first and most frequently
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