:-/ Is there a earthquake fault line in the state of Pennsylvania ?

speedball1

Hi Johnny, :-/ Yes there are fault lines in Pennsylvania. Read on; ORIGINATOR: Pennsylvania Bureau of Topographic and Geologic Survey, Department of Conservation and Natural Resources
TITLE: Bedrock Geologic Units, Faults, and Dikes, Sunbury 30- by 60- Minute Quadrangle, East-Central Pennsylvania
ONLINE LINK: Download
ABSTRACT: The data set for geologic units, faults, and dikes for the Sunbury 30- by 60-minute quadrangle is part of a digital version of the 1980 "Geologic Map of Pennsylvania" (Berg and others, 1980). The 1980 map, which was published by the Pennsylvania Bureau of Topographic and Geologic Survey (PaGS), shows the areal distribution and extent of bedrock geologic units in Pennsylvania. The 1980 map was compiled and published at the scale of 1:250,000 in a transverse mercator projection. The two digital data sets, one for geologic units and faults, and the other for dikes, were prepared using ARC/INFO software and are provided in a geographic coordinate system (units in decimal degrees). Although it is possible to portray digital data at any scale, the geologic formational contacts, faults, and dikes represented in these data sets are not intended to be used at any scale finer than 1:250,000. The polygon attributes in the data set for geologic contacts and faults include unit number, map symbol, name, age, and three lithology categories that represent the general lithologic makeup of each geologic unit shown on the 1980 map. Each arc (line) in the data set is attributed as one or more of the three general categories of contact, fault, or border. Contact lines are attributed according to the type of contact shown on the 1980 map (solid, dashed, queried, or abitrary). Fault lines are similarly attributed (solid, dashed, or queried). Borders are attributed as either state boundaries or quadrangle boundaries. The data set for dikes consists of arcs attributed with unit number, map symbol, name, age, lithology, and type of dike (solid or dashed). In compiling the data set for the geologic units, the PaGS initially used a data set prepared from the 1980 state geologic map by the U.S. Geological Survey, Water Resources Division (USGS-WRD) in the late 1980’s and early 1990’s. The USGS-WRD data set was extensively modified by the PaGS as follows: (1) contacts, faults, and latitude/longitude control points from the artwork and/or source materials used to prepare the 1980 map were scanned and georeferenced by the PaGS, and all polygons from the USGS-WRD data set were revised or redigitized by the PaGS based on the new georeferenced scans; (2) errors in the labeling of geologic units were corrected, and many label points were relocated to fit revised locations of polygons; (3) five items (unit number, age, and three lithology categories) were added to the polygon attribute table by the PaGS, and the two items for symbol and name of the geologic units were revised; (4) fault lines were added and attributed by the PaGS; and (5) six items were added to the arc attribute table to distinguish the types of contact lines, fault lines, and border lines in the data set. The data set for dikes was prepared entirely by the PaGS. The Sunbury 30- by 60-minute quadrangle encompasses most of Schuylkill and Northumberland Counties and parts of Columbia, Dauphin, Snyder, Berks, Union, Montour, Luzerne, Lebanon, Perry, and Juniata Counties. The geologic units mapped at 1:250,000 scale in the quadrangle range from the Pennsylvanian-age Llewellyn Formation to the Ordovician-age shale and graywacke of the Hamburg sequence. Good luck and I hope your house isn't setting on top of one. Tom