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Physical Sciences and Mathematics Commons

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Geology

Selected Works

Ocean Drilling Program

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

Cooling Rates And The Depth Of Detachment Faulting At Oceanic Core Complexes: Evidence From Zircon Pb/U And (U-Th)/He Ages, C. B. Grimes, Michael Cheadle, Barbara John, P. W. Reiners, J. L. Wooden Jun 2012

Cooling Rates And The Depth Of Detachment Faulting At Oceanic Core Complexes: Evidence From Zircon Pb/U And (U-Th)/He Ages, C. B. Grimes, Michael Cheadle, Barbara John, P. W. Reiners, J. L. Wooden

Barbara John

Oceanic detachment faulting represents a distinct mode of seafloor spreading at slow spreading mid-ocean ridges, but many questions persist about the thermal evolution and depth of faulting. We present new Pb/U and (U-Th)/He zircon ages and combine them with magnetic anomaly ages to define the cooling histories of gabbroic crust exposed by oceanic detachment faults at three sites along the Mid-Atlantic Ridge (Ocean Drilling Program (ODP) holes 1270D and 1275D near the 15 degrees 20'N Transform, and Atlantis Massif at 30 degrees N). Closure temperatures for the Pb/U (similar to 800 degrees C-850 degrees C) and (U-Th)/He (similar to 210 …


How Synchronous Are Neogene Marine Plankton Events?, Cinzia Spencer-Cervato, Hans R. Thierstein, David B. Lazarus, Jean-Pierre Beckmann Oct 1994

How Synchronous Are Neogene Marine Plankton Events?, Cinzia Spencer-Cervato, Hans R. Thierstein, David B. Lazarus, Jean-Pierre Beckmann

Cinzia Cervato

An electronic supplement of this material may be obtained on adiskette or Anonymous FTP from KOSMOS.AGU.ORG. (LOGIN toAGU's FTP account using ANONYMOUS as the username andGUEST as the password. Go to the right directory by typing CDAPEND. Type LS to see what files are available. Type GET and thename of the file to get it. Finally, type EXIT to leave the system.)(Paper 94PA01456, How synchronous are Neogene marine planktonevents?, by C. Spencer-Cervato, H. R. Thierstein, D. B. Lazarus, andJ-P Beckmann). Diskette may be ordered from American GeophysicalUnion, 2000 Florida Avenue, N.W., Washington, DC 20009; $15.00.Payment must accompany order. We analyzed …