In 1984, the U.S. Geological Survey conducted a detailed geologic analysis of two nuclear test craters at Enewetak Atoll, Marshall Islands, on behalf of the Defense Nuclear Agency. A multidisciplinary task force mapped the morphology, surface character, and subsurface structure of two craters, OAK and KOA. The field mapping techniques include echo sounding, sidescan sonar imaging, single-channel and multichannel seismic reflection profiling, a seismic refraction survey, and scuba and submersible operations. All operations had to be navigated precisely and correlatable with subsequent drilling and sampling operations.
Mapping with a high degree of precision at scales as large as 1:1500 required corrections that often are not considered in marine mapping. Corrections were applied to the bathymetric data for location of the echo- sounding transducer relative to the navigation transponder on the ship and for transducer depth, speed of sound, and tidal variations. Sidescan sonar, single-channel seismic reflection, and scuba and submersible data were correlated in depth and map position with the bathymetric data to provide a precise, internally consistent data set. The multichannel and refraction surveys were conducted independently but compared well with bathymetry. Examples drawn from processing the bathymetric, sidescan sonar, and single- channel reflection data help illustrate problems and procedures in precision mapping.
|Publication type||Conference Paper|
|Publication Subtype||Conference Paper|
|Title||Mapping nuclear craters on Enewetak Atoll, Marshall Islands|
|Contributing office(s)||Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center|
|Larger Work Type||Book|
|Larger Work Subtype||Conference publication|
|Larger Work Title||Proceedings International Symposium on Marine Positioning|
|Conference Title||Marine Positioning International Symposium: Positioning the Future|
|Conference Location||Reston, VA|
|Conference Date||October 14-17, 1986|
|Other Geospatial||Enewetak Atoll|
|Online Only (Y/N)||N|
|Additional Online Files (Y/N)||N|
|Google Analytic Metrics||Metrics page|