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Database for the Preliminary Map of the Surface Rupture from the August 9, 2020, Mw 5.1 Earthquake Near Sparta, North Carolina-The Little River Fault and Other Possible Coseismic Features
This publication is a preliminary map and geodatabase of the coseismic surface rupture and other coseismic features generated from the August 9, 2020, Mw 5.1 earthquake near Sparta, North Carolina. Geologic mapping facilitated by analysis of post-earthquake quality level 0 to 1 lidar, document the coseismic surface rupture, named the Little River fault, and other coseismic features. The Little River fault is traced for approximately 4 kilometers and cuts the regional Paleozoic fabric (mean foliation, 063°/57°), and the dominant strike of joint sets are 0°–10°, 130°–150° and 320°–340°. Individual fault strands occur in an en echelon pattern within an approximately 10-meter-wide zone. Trenches across the Little River...
The Quaternary Fault and Fold Database contains the results of thousands of scientific assessments of faults and associated folds in the United States that demonstrate geologic evidence for coseismic surface deformation in the Quaternary (the past 1,600,000 years). The Quaternary Fault and Fold Database includes information on the age of the most recent coseismic surface deformation, relative rates of activity, fault geometry, sense of movement, and citations of pertinent literature. Much of the information in the database is based on paleoseismology, which is the geologic study of prehistoric earthquakes. Paleoseismology combines well-established geologic practices such as trenching with archeological-style analysis...
Full-resolution photomosaics of trench walls from the 2006 paleoseismic study of the San Andreas Fault at Coachella, California
The Coachella paleoseismic site is located on the San Andreas Fault along the northeast edge of the Coachella Valley in southern California, southwest of the intersection of Dillon Road and Avenue 44. In 2006, three benched trenches were excavated across the fault zone as part of an Alquist-Priolo fault investigation study by a private geotechnical firm (see APSI_003361 at https://maps.conservation.ca.gov/cgs/informationwarehouse/apreports/). These trenches exposed a thick section of latest Holocene lacustrine, alluvial, and shoreline deposits. Only the central and eastern trenches exposed faulting so paleoseismic investigations were confined to those two trenches. In the central trench (T1), we photographed and...