Arkansas Earth Quake
USGS Earthquake Hazards Program: 1811 - 1812 Earthquakes in the New Madrid Seismic Zone
The magnitude of these series of earthquakes,usually named the New Madrid, Missiouri, earthquakes,vary considerably between the mb and Ms valuesestimated by Nuttli. The mb was estimated from isoseismal maps,and the MS was estimatedfrom a spectral scaling relation by Nuttlifor mid-plate earthquakes. The value of MSmagnitude has a functional relationship to the mb.The authors have chosen to include the Mfa magnitudebecause it was estimatedfrom isoseismal maps, as were most of the historicalearthquakes. ... [Read More]
USGS Earthquake Hazards Program: The Mississippi Valley Earthquakes of 1811 and 1812
The felt areas of the threelargest earthquakes were extremelylarge. They extended south to thegulf coast, southeast to the Atlanticcoast, and northeast to Quebec,Canada. The western boundarycannot be established owing to alack of population. However, it canbe estimated that the area of intensity Vor greater effects was approximately2½ million square kilometers.This can be contrastedwith the 1906 San Francisco earthquake,for which the area of intensity Vor greater effects was about150,000 square kilometers. Thelarge difference in felt areasbetween the Mississippi Valley andSan Francisco earthquakes, whichhad approximately the same magnitudeand focal depth, can be explainedby differences in attenuationof earthquake waves travelingthrough the Earth's outer crust.The crust in the Western United Statestends to ``soak up'' earthquakeenergy, whereas in the central and easternregions of thecountry the seismic energy experiencesa much lower rate of absorption.Quantitative studies of rece ... [Read More]
The Mississippi Valley-"Whole Lotta Shakin' Goin' On"
Recognizing these problems, the U.S. Geological Survey (USGS) and otherorganizations are joining in actions that will greatly reduce loss of lifeand property in future temblors: In 1983, the states of Arkansas, Illinois, Indiana, Kentucky, Mississippi,Missouri, and Tennessee formed the Central United States EarthquakeConsortium (CUSEC). CUSEC improves public earthquake awareness and education;coordinates multistate planning for earthquake preparedness, response, andrecovery; and encourages research in earthquake hazard reduction. In 1990, the USGS, advised by private, academic, and government experts,issued a plan for intensified study of the New Madrid seismic zone. At thesame time, the National Earthquake Hazards Reduction Program expanded effortsin the central United States. Earthquake education is now part of the curriculum in the schools of manyCUSEC states. In Kentucky, the state legislature has mandated that earthquakeeducation be taught in schools. Earthquake Awareness Weeks h ... [Read More]
NASA CONNECT™ Hidden Treasures: Landscape Archeology
In NASA CONNECT™: Landscape Archaeology: Hidden Treasures , students willlearn how researchers and scientists use data collected through remote sensingto study hidden features on the Earth’s surface and to discover the environmentaland archaeological effects left by ancient cultures. Students will see how archaeologistsuse the math concepts of coordinate geometry and powerful geographic informationsystem (GIS) software to solve current world problems by investigating cluesfrom the past. By conducting inquiry-based and web activities, students willmake connections between NASA research and the mathematics, science, and technologythey learn in their classrooms. ... [Read More]
Quake: USGS Earthquake News Releases (archives)
More than 16,000 earthquakes recorded in this century... New Map Pinpoints Past Caribbean Earthquakes ... Alaska and Washington Yield Largest U.S. Earthquakes. . . Most Significant Earthquakes of '96 Rattle China, Indonesia ... Fewer Major Earthquakes But...Earthquakes Take More Lives in 1997 ... [Read More]
Earthquake Hazards Program: NEIC: Worldwide Earthquake Activity in the Last Seven Days
Earthquake List Only (Printer Friendly Version) * Earthquake Map Only (new window) ... Maps of Current Worldwide Earthquakes * Comma-delimited Earthquake List ... Last 8-30 Days of Earthquake Activity * Large/Noteworthy Earthquakes in 2004 ... [Read More]
Earthquake Hazards Program: United States Earthquake Information
If you are looking for an earthquake that you think has just occurredin your State, please check the Current Earthquake List for information.Although you may have felt the earthquake, the actual location may be in a nearby State. ... Earthquake Activity in the Last 8 - 30 Days ... Earthquake Activity ... [Read More]
FEMA: Earthquake Information
There are 45 states and territories in the United States at moderate to very high risk from earthquakes, and they are located in every region of the country. California experiences the most frequent damaging earthquakes; however, Alaska experiences the greatest number of large earthquakes—most located in uninhabited areas. The largest earthquakes felt in the United States were along the New Madrid Fault in Missouri, where a three-month long series of quakes from 1811 to 1812 included three quakes larger than a magnitude of 8 on the Richter Scale. These earthquakes were felt over the entire Eastern United States, with Missouri, Tennessee, Kentucky, Indiana, Illinois, Ohio, Alabama, Arkansas, and Mississippi experiencing the strongest ground shaking. ... [Read More]
Earthquake Myths
There's nothing I can do about earthquakes, so why worry about them? It's true that earthquakes can't be stopped, but you can be prepared. You can prepare an earthquake kit (food, water, flashlight, etc.), practice "duck, cover and hold" drills at home with your family and at work, and develop an earthquake plan (where would you meet family members if you weren't together when an earthquake hit?). ... Dogs and other animals can “sense” when an earthquake is going to strike . It's impossible to determine whether a dog is behaving in an unusual manner because it smells an earthquake coming or a cat across the street. Changes in animal behavior sometimes have been observed prior to earthquakes, but that behavior is not consistent, and sometimes there's no perceptible behavior change prior to an earthquake. ... [Read More]
Department of Conservation - Maps
How often do earthquakes happen? The National Earthquake Information Center (U.S.) reports 12,000-14,000 earthquakes a year around the world, or 35 a day. Throughout the world, there are one "great" (magnitude 8.0 or more), 18 "major" (7.0-7.9), 120 "large" (6.0-6.9) and 1,000 "moderate" (5.0-5.9) earthquakes in an average year. Each year, California generally gets two or three earthquakes large enough to cause moderate damage to structures (magnitude 5.5 and higher). ... [Read More]
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