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Department of the Interior Us Geological Survey DEPARTMENT OF THE INTERIOR U.S. GEOLOGICAL SURVEY Estimation of Earthquake Effects Associated with Large Earthquakes in the New Madrid Seismic Zone By Margaret G. Hopper , Editor Open-File Report 85-457 Prepared in cooperation with Federal Emergency Management Agency (FEMA) Central United States Earthquake Preparedness Project This report is preliminary and has not been reviewed for conformity with U.S Geological Survey editorial standards and stratigraphic nomenclature. 1U.S. Geological Survey Denver, Colorado 80225 1985 CONTENTS Page Abstract, by Margaret G. Hopper and S. T. Algerraissen..................... 1 Introduction, by Margaret G. Hopper....................................... 2 Historical seismicity of the Mississippi Valley, by Margaret G. Hopper.... 5 Earthquakes of 1811-1812............................................. 5 Other large earthquakes in the region................................ 9 January 5, 1843 ................................................. 14 October 31, 1895 ................................................ 16 November 9, 1968................................................ 17 Seismicity of the New Madrid seismic zone............................ 19 Probability of large earthquakes in the Mississippi Valley, by S. T. Algermissen....................................................... 22 Earthquake of maximum magnitude...................................... 22 Recurrence of large shocks........................................... 23 Nature of liquefaction and landslides in the New Madrid earthquake region, by Stephen F. Obermeier......................................... 24 Liquefaction, liquefaction potential, and liquefaction- induced problems................................................... 24 Conditions for liquefaction..................................... 24 Consequences of liquefaction.................................... 28 Engineering evaluation of liquefaction potential................ 30 Solutions to liquefaction....................................... 36 Landslides not caused by liquefaction................................ 36 Landslides in steep loess uplands............................... 36 Landslides along streams........................................ 37 Variations in Modified Mercalli intensities, by Margaret G. Hopper........ 39< Causes of variations in intensity patterns........................... 39 Effects due to liquefaction and landsliding.......................... 40 Predominant periods of ground motion................................. 41 Maps of hypothetical intensities for the region, by S. T. Algermissen and Margaret G. Hopper.................................................. 42 Construction of the maps............................................. 42 Areas of proj ected minimal damage.................................... 50 Maps of hypothetical intensities for seven cities, by Ernest Dobrovolny, Stephen F. Obermeier, and Margaret G. Hopper................ 52 Estimation of intensities at Carbondale, Illinois.................... 74 Physiographic description....................................... 74 Underlying material............................................. 74 Physical property tests and other information................... 74 Potential for landslides, liquefaction, and other geologic effects....................................................... 74 Hypothetical intensity maps for Carbondale...................... 74 Estimation of intensities at Evansville, Indiana..................... 75 Physiographic description....................................... 75 Underlying material............................................. 75 Physical property tests and other information................... 75 Potential for landslides, liquefaction, and other geologic effects....................................................... 75 Hypothetical intensity maps for Evansville...................... 76 CONTENTS ContInued Page Maps of hypothetical intensities for seven cities Continued Estimation of intensities at Little Rock and North Little Rock, Arkansas........................................................... 76 Physiographic description....................................... 76 Underlying material............................................. 76 Physical property tests and other information................... 77 Potential for landslides, liquefaction, and other geologic effects....................................................... 77 Hypothetical intensity maps for Little Rock and North Little Rock.......................................................... 78 Estimation of intensities at Memphis, Tennessee...................... 78 Physiographic description....................................... 78 Underlying material............................................. 78 Physical property tests and other information................... 78 Potential for landslides, liquefaction, and other geologic effects....................................................... 83 Hypothetical intensity maps for Memphis......................... 83 Estimation of intensities at Paducah, Kentucky....................... 86 Physiographic description....................................... 86 Underlying material............................................. 86 Physical property tests and other information................... 86 Potential for landslides, liquefaction, and other geologic effects....................................................... 86 Hypothetical intensity maps for Paducah......................... 86 Estimation of intensities at Poplar Bluff, Missouri.................. 87 Physiographic description....................................... 87 Underlying materials............................................ 87 Physical property tests and other information................... 87 Potential for landslides, liquefaction, and other geologic effects....................................................... 87 Hypothetical intensity maps for Poplar Bluff.................... 88 Estimation of intensities at Saint Louis, Missouri................... 88 Physiographic description....................................... 88 Underlying material............................................. 88 Physical property tests and other information................... 89 Potential for landslides, liquefaction, and other effects....... 90 Hypothetical intensity maps for city and county of Saint Louis, Missouri ............................................... 91 Potential for liquefaction in areas of Modified Mercalli intensities IX and greater, by Stephen F. Obermeier and Norman Wingard.............. 92 Map units and potential for liquefaction............................. 92 Potential for liquefaction in Arkansas............................... 93 Potential for liquefaction in Illinois............................... 94 Potential for liquefaction in Indiana................................ 95 Potential for liquefaction in Kentucky............................... 96 Potential for liquefaction in Mississippi............................ 97 Potential for liquefaction in Missouri............................... 98 Potential for liquefaction in Tennessee.............................. 99 ii CONTENTS Continued Page Aerial reconnaissance study of areas that may have sandblows caused by the New Madrid earthquakes, by D. D. Dickey.......................... 100 Introduction......................................................... 100 Criteria used for identifying sandblows on aerial photographs........ 100 Time of photography problem.......................................... 102 Relation of sandblows to soil types.................................. 102 Photography available................................................ 102 Photography examined................................................. 103 Conclusions, by Margaret G. Hopper........................................ 106 Appendix 1................................................................ 108 Modified Mercalli intensity scale of 1931 ............................ 108 Appendix 2................................................................ 114 Effects of the 1811-12, 1843, 1895, and 1968 earthquakes at Carbondale, Illinois............................................... 114 Appendix 3................................................................ 116 Effects of the 1811-12, 1843, 1895, and 1968 earthquakes at Evansville, Indiana................................................ 116 Appendix 4................................................................ 118 Effects of the 1811-12, 1843, 1895, and 1968 earthquakes at Little Rock, Arkansas.............................................. 118 Appendix 5 ................................................................ 120 Effects of the 1811-12, 1843, 1895, and 1968 earthquakes at Memphis, Tennessee................................................. 120 Appendix 6................................................................ 123 Effects of the 1811-12, 1843, 1895, and 1968 earthquakes at Paducah, Kentucky.................................................. 123 Appendix 7................................................................ 125 Effects of the 1811-12, 1843, 1895, and 1968 earthquakes at Poplar Bluff, Missouri............................................. 125 Appendix 8................................................................ 127 Effects of the 1811-12, 1843, 1895, and 1968 earthquakes at Saint Louis, Missouri.............................................. 127 References................................................................ 134 ILLUSTRATIONS
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