Data was collected aboard Alaska Department of Fish and Game’s R/V Medeia and would not be possible without the support of vessel crew members Jim deLaBruere, Craig Conger, Cedar Stark, and Becky Wilson.
The Queen Charlotte-Fairweather Fault (QCFF) is a major structural feature that extends more than 1,200 km from northern Vancouver Island, Canada to the Fairweather Range of southern Alaska. The fault system represents a major transform boundary that separates the Pacific Plate from the North American Plate, and in many ways, can be considered an analog ‘sister’ fault to California’s San Andreas Fault. Early studies in the 1970s and 1980s based on historical marine geophysical data demonstrated that approximately 75 percent of the system is located offshore along the continental shelf-edge and slope, more than 20-50 km from land in eastern Gulf of Alaska. Historical seismicity records dating back to 1890 include dozens of large magnitude earthquakes, including eight events of magnitude greater than 7 and Canada’s largest earthquake on record (1949, M8.1). Finally, two recent earthquakes, a M7.8 in 2012 (“Haida Gwaii earthquake”) and M7.5 in 2013 (“Craig earthquake”) stimulated a substantial amount of scientific study of the QCFF and renewed concern over potential threats to coastal infrastructure and populations residing in southeastern Alaska and northwestern British Columbia. Survey goals included determining how fast the two sides of the fault move past each other (slip rate) and deciphering the historical movement of the fault. We also want to better understand how large earthquakes might trigger potentially dangerous underwater landslides. The purpose of this data is to provide a detailed bathymetric terrain model of a portion of the Queen Charlotte Fault and adjacent seafloor.
Are there legal restrictions on access or use of the data?
Use_Constraints:USGS-authored or produced data and information are in the public domain from the U.S. Government and are freely redistributable with proper metadata and source attribution. Please recognize and acknowledge the U.S. Geological Survey as the originator of the dataset and in products derived from these data. This information is not intended for navigation purposes.
Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty.
|Data format:||Zip files are organized by Julian Day of collection and contain raw multibeam bathymetry data, raw navigation data and ship motion data. Associated metadata is downloadable separately. Individual zip files are available for individual download from the listing at https://www.sciencebase.gov/catalog/item/5a0a213fe4b09af898c9ef04 in format ASCII Size: 22250|
HSX and RAW files can be viewed with any text editor capable of reading ASCII format including WordPad and Text wrangler, in addition to Caris HIPS and SIPS, SonarWiz, and Qimera. 7K files can be viewed using Fledermaus FMMidwater software or other software described on Teledyne's website (http://www.teledyne-pds.com/wp-content/uploads/2017/06/DATA-FORMAT-DEFINITION-7k-Data-Format-Version-3.07.pdf).