| Abstract: | Compositions of lavas from seven small to medium-sized seamounts offshore southern and Baja California, include low-K2O tholeiitic, transitional, and mildly to moderately alkalic basalt and their differentiates. The seamounts with these MORB-like lavas are inferred to have formed at or near the spreading center. Based on 40Ar/39Ar laser fusion techniques, MORB-like lava from one of the northern edifices is as old as the underlying oceanic crust (>20 Ma), indicating that it originated at a spreading center. Other seamount lava ages are much younger than the oceanic crust on which they reside. Some of the seamounts with transitional and alkalic lavas may have formed as part of a short, age-progressive chain formed by a short-lived mantle plume. Many others, may have resulted from upwelling mantle diapirs in response to localized extension. -from Authors |
| Genre: | Article |
| ProdID: | 70018826 |
| Citation Author: | Davis, A. S.; Gunn, S. H.; Bohrson, W. A.; Gray, L. -B.; Hein, J. R. |
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| Citation End Page: | 570 |
| Citation Issue: | 5 |
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| Citation Language: | English |
| Citation Larger Work Title: | Geological Society of America Bulletin |
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| Citation Number Of Pages: | 17 |
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| Citation Search Results Text: | Chemically diverse, sporadic volcanism at seamounts offshore southern and Baja California; 1995; Article; Journal; Geological Society of America Bulletin; Davis, A. S.; Gunn, S. H.; Bohrson, W. A.; Gray, L. -B.; Hein, J. R. |
| Citation Start Page: | 554 |
| Citation Volume: | 107 |
| Citation Year: | 1995 |
| Type: | citation/reference |
| Text: | Chemically diverse, sporadic volcanism at seamounts offshore southern and Baja California; 1995; Article; Journal; Geological Society of America Bulletin; Davis, A. S.; Gunn, S. H.; Bohrson, W. A.; Gray, L. -B.; Hein, J. R. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| Date Other: | Sun, 1 Jan 1995 00:00 -0600 |
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