Guyots of the Dutton Ridge at the Bonon/Mariana Trench Juncture as Shown by Multi-Beam Surveys
1983; University of Chicago Press; Volume: 91; Issue: 2 Linguagem: Inglês
10.1086/628757
ISSN1537-5269
Autores Tópico(s)Geology and Paleoclimatology Research
ResumoVery accurate bathymetric data for five guyots from the newly named Dutton Ridge are presented along with that of two associated nearby guyots. These new data are based on U.S. Naval Oceanographic Office swath mapping by the SASS multi-beam sonar system (Glenn 1970). The Dutton Ridge is a major east-west trending feature that intersects the junction of the Bonin and Mariana Trenches. Its trend parallels that of the Michelson Ridge, which lies further to the North at the intersection of the Izu and Bonin trenches. As of this writing no samples have yet been dredged from the Dutton guyots, but the new bathymetric data presented allows some interpretation of the geologic history of the ridge. I suggest that the Dutton Ridge formed as a volcanic plateau at the extinct triple junction of the Phoenix, Farallon, and Pacific Plates. This once-continuous plateau was then fractured and faulted to produce the present group of guyots and ridges. Later volcanism may have altered its morphology. Subsequently, the ridge passively rode along on the Pacific Plate to its present location where it may be jamming the trench juncture, as indicated by a lack of seismic activity at that spot. In addition, bathymetric evidence indicates that the Dutton Ridge may have been partly obducted onto the arc-trench slope.
Referência(s)