Skip to main content

Susan Rhea

thumbnail
This map illustrates more than one century of global seismicity in the context of global plate tectonics and the Earth's physiography. Primarily designed for use by earth scientists and engineers interested in earthquake hazards of the 20th and early 21st centuries, this map provides a comprehensive overview of strong earthquakes since 1900. The map clearly identifies the location of the 'great' earthquakes (M8.0 and larger) and the rupture area, if known, of the M8.3 or larger earthquakes. The earthquake symbols are scaled proportional to the moment magnitude and therefore to the area of faulting, thus providing a better understanding of the relative sizes and distribution of earthquakes in the magnitude range...
thumbnail
This cover contains faults in the unconformity at the Cambrian-Precambrianboundary. These data were contributed byGlenn Bear of Indiana University as part of the work onhis doctoral thesis. The southern part of the map was produced byJames Drahovzal of the Kentucky Geological Survey and merged withBear's map of the rest of the map area and beyond.Public and proprietary seismic reflection and welldata were used to define the basement structure.A prominent east-west structure in the southern half of the maparea is the western end of the Rough Creek Graben. At its deepestpoint the unconformity is more than 30,000 ft(9,100 m) below sea level. Faulted strata at this depth mean thatthe Rough Creek Fault System penetrates...
Tags: 1100 - Geology, 1101 - General, 17025 = Clay, 17047 = Edwards, 17055 = Franklin, All tags...
thumbnail
The northern part of the map area and large adjacent regions havebeen severely shaken by one or more moderate to large prehistoricearthquakes. The evidence of these takes the form ofpaleoliquefaction features, including shaking-induced sandblows anddikes that fed them.Over several summer field seasons from 1990 through 1994,several workers searched ditches and river banks for evidenceof liquefaction. They found numerous dikes and sandblows.This database includes the locations and descriptions of dikes theyobserved and measured.The most widespread paleoliquefaction is attributed to amid-Holocene earthquake near what is now Vicennes, IN, with anestimated moment- magnitude of about 7.5. Stratigraphic,geomorphological,...
Tags: 1500 - Hazards, 1501 - Earthquakes, 17025 = Clay, 17047 = Edwards, 17055 = Franklin, All tags...
thumbnail
The northern part of the map area and large adjacent regions havebeen severely shaken by one or more moderate to large prehistoricearthquakes. The evidence of these takes the form of paleoliquefactionfeatures, including shaking-induced sandblows and dikes that fed them.Over several summer field seasons between 1990 and 1994, Cheryl andPat Munson, along with several of their students, searched ditchesand river banks for evidence of liquefaction. They found numerousbanks with shaking-induced sandblows and the dikes that fed them.This database includes the location of dikes thatthe Munsons and those with them observed and measured. Dike thicknesswas divided into 5 classes, 1 being the smallest at 0-4 cm, 2 = 5-14 cm,3...
Tags: 1500 - Hazards, 1501 - Earthquakes, 17025 = Clay, 17047 = Edwards, 17055 = Franklin, All tags...
View more...
ScienceBase brings together the best information it can find about USGS researchers and offices to show connections to publications, projects, and data. We are still working to improve this process and information is by no means complete. If you don't see everything you know is associated with you, a colleague, or your office, please be patient while we work to connect the dots. Feel free to contact sciencebase@usgs.gov.