Arctic Ocean Geophysical Studies: The Alpha Cordillera and Mendeleyev Ridge

• Main Author: Hall, John K.
• Other Authors: LAMONT-DOHERTY GEOLOGICAL OBSERVATORY PALISADES NY
• Format: Text
• Language: English
• Published: 1970
• Subjects: Physical and Dynamic Oceanography; Geology; Geochemistry and Mineralogy; *OCEAN BOTTOM TOPOGRAPHY; *ARCTIC OCEAN; *MARINE GEOPHYSICS; REFLECTION; FAULTS(GEOLOGY); GRAVITY; REFRACTION; GEOLOGIC AGE DETERMINATION; BATHYTHERMOGRAPH DATA; SEDIMENTATION; ECHO RANGING; OCEANIC CRUST; MAGNETIC ANOMALY DETECTION; MEASUREMENT; DEPTH FINDING; COMPUTER PROGRAMS; ANOMALIES; OCEAN BOTTOM SPREADING; ALPHA CORDILLERA; SEISMIC PROFILES; Arctic; Arctic Ocean; Canada; Mid-Atlantic Ridge; Mendeleyev; Mendeleyev Ridge; Chukchi Rise; Alpha Cordillera; Chukchi
• Online Access: http://www.dtic.mil/docs/citations/AD0715656; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=AD0715656

The geophysical findings from Fletcher's Ice Island (T-3) for the period mid-1962 to mid-1970 are presented. During this time the ice station traversed the Chukchi Rise, portions of the Alpha Cordillera and Mendeleyev Ridge, and the Chukchi, Mendeleyev, and Canada Plains. The findings, together with pertinent observations from older investigations, support the suggestion of earlier investigators that the Alpha Cordillera is an inactive center of seafloor spreading. Several fractures were observed to cut the Mendeleyev Ridge and Alpha Cordillera, and many other closely spaced fractures are suggested by topographic, magnetic, and gravity trends. These fractures appear to parallel the 142 degrees West meridian. Seismic reflection profiles show a buried topography similar to that of the Mid-Atlantic Ridge. Offsets in the apparent axial rift suggest that the fractures are the traces of transform faults. The angular relationship between the Mendeleyev Ridge and the Alpha Cordillera appears to result from a southerly displacement of the cordillera crest along numerous en echelon transform faults. Magnetic anomalies are consistent with the seafloor spreading hypothesis.