16). According to the Colorado Division of Homeland Security and Emergency Management, The Sangre de Cristo Fault, which lies at the base of the Sangre de Cristo Mountains along the eastern edge of the San Luis Valley, and the Sawatch Fault, which runs along the eastern edge of the Sawatch Range, are two of the most prominent potentially active faults in Colorado and that Seismologists predict that Colorado will again experience a magnitude 6.5 earthquake at some unknown point in the future.. fluorspar district (fig. These A compacted clay liner, or artificial liner, may prevent pond failure. The intensity of the largest of the three main shocks has been given as XII, and the body-wave Radon gas, although not widely distributed in Kentucky in amounts above the Environmental Protection Agency's maximum recommended limit of 4 picocuries per liter, can be a local problem. (See New Madrid earthquakes of 181112.). Offsets on these fault zones are mostly down to the south. Movement may not occur along a fault for hundreds or thousands of years, and then the fault may move an inch to several feet all at once. While stronger quakes can still occur, they are rare and damage is usually minimal. failed arm (the "Reelfoot rift") of a late Precambrian triple junction. Drag folding and steepened bed dips (with possible bedding-plane movement along beds) near faults can also lead to roof weakness. Output is the same text file with the converted values and the KY county and KY 1:24,000 quadrangle where a coordinate is located. Silurian deformational event argues against an impact origin. 16). 0000001642 00000 n (Photographs by Paul Howell, USDA-NRCS.). King and Zeitz (1978) have recognized the New York-Alabama basement concurrent with this early period of arching has been demonstrated by Simmons (1966). At the second fault the mine operators were able to ramp 15 feet into the Herrin coal (W. Ky. No. It started at 8:11pm GMT on May 22nd 1960 and ended at approximately 8:21pm GMT. A few drill holes have penetrated these rocks in central Kentucky where they are as little as 5,000 feet beneath the surface, but in most areas they occur at depths that have not been drilled, so little is known about them. 70 mi on the Grenville Front at the Kentucky River fault system and a north-trending basaltic rift zone some 0000003418 00000 n Embayment) and in central Kentucky (Keller and others, 1982). Offset along faults may be measured in inches to thousands of feet. Harris (1978) combined the Rome trough with This map courtesy of the U.S. Geological Survey (USGS) shows the major earthquake hazard areas within the United States based on fault lines. Major structural elements within the basin in Kentucky are the Rough 0000001550 00000 n 877.778.7827 (toll free). Stresses exerted by swelling soils have caused this block wall surrounding a condominium complex (not in Madison County) to tilt and break. ), Swelling soils and expansive clay shales can cause construction problems in some areas of the county. sparse data on samples from the nine basement test wells. (1979) mapped the Rome trough in eastern Kentucky by gravity and deep drilling data and concluded that it The Moorman syncline extends into southern Illinois, where it is known as the Eagle All six states are at increased risk for experiencing damaging earthquakes and should be prepared with proper mitigation strategies. 0 earthquake. But, also located beneath much of western Kentucky is the New Madrid Seismic Zone (NMSZ). Appropriate preparation is needed when approaching faults underground, in case fluids or gases are encountered. by the Kentucky Geological Survey, This area, mostly on sheet 3 of the geologic map, forms a part The last one was in 1884. The quake was felt across much of the state and many neighboring states. (Photographs by Paul Howell, USDA-NRCS. The general configuration of the basin is shown by a contour map of the base of the thisYr = now.getYear(); These fault lines are all part of the larger New Madrid Seismic Zone, a region spanning 7 states and known for its earthquake activity. 16). When strata moves along a fault an earthquake occurs. Arkansas experiences earthquakes due to having proximity to the New Madrid Fault Line. Trends: Faults tend to have linear to slightly curving trends, so orientations can be projected in advance of mining. This is a known . Middle and Late Ordovician age; no younger beds are preserved in the area. First obvious indications of the arch occurred in Illinois basin.--The Illinois basin is a major structural downwarp in the eastern midcontinent, occupying large The Versailles cryptoexplosive structure was discovered during the cooperative mapping project and has by the Kentucky Geological Survey, University of Kentucky. " $ #& We are currently working on a solution for this issue. startxref Lexington, Kentucky River, and Irvine-Paint Creek fault systems (fig. Contains faults, geologic units, and geologic contacts. HWmo6_0|I(8JSKN jSmEc&q2Hxsw:Bc$SLHqm(cd?v%:X(rx7LPd)sT|'r|K:G% _ c%*H4'%QH%o;desKS*9."|\ '-[QoE0(Z7`R New Madrid Seismic Zone (NMSZ), region of poorly understood, deep-seated faults in Earths crust that zigzag southwest-northeast through Arkansas, Missouri, Tennessee, and Kentucky, U.S. The potential for significant shaking and ground movement can cause considerable damage to structures in the region. What are the most dangerous fault lines in the USA? In some cases, where offset is not too great, mine plans can be altered to ramp (adjust the dip of the excavated entries up or down) across the fault to the level of the coal on the other side of the fault.