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Gee, J, Kent DV.  1994.  Variations in Layer 2A Thickness and the Origin of the Central Anomaly Magnetic High. Geophysical Research Letters. 21:297-300.   10.1029/93gl03422   AbstractWebsite

The seismically determined off-axis thickening of the extrusive layer is apparently at odds with the magnetic anomaly high typically associated with the ridge crest. The positive magnetization contrast at the ridge crest is most likely caused by rapid alteration of the extrusive source layer which occurs over spatial scales (2-3 km) comparable to that of the proposed Layer 2A thickening. We present magnetic remanence data from basalts dredged on and near the East Pacific Rise axis at 12-degrees-N which are compatible with a rapid magnetization reduction (approximately 20 k.y. to decay to 1/e). Together with near bottom magnetic profiles from the ultra-fast-spreading East Pacific Rise at 19.5-degrees-S, these data suggest that previous estimates of the time constant of alteration inferred from slow-spreading ridges (0.5 m.y.) may be more than an order of magnitude too high.

Granot, R, Tauxe L, Gee JS, Ron H.  2007.  A view into the Cretaceous geomagnetic field from analysis of gabbros and submarine glasses. Earth and Planetary Science Letters. 256:1-11.   10.1016/j.epsl.2006.12.028   AbstractWebsite

The nature of the geomagnetic field during the Cretaceous normal polarity superchron (CNS) has been a matter of debate for several decades. Numerical geodynamo simulations predict higher intensities, but comparable variability, during times of few reversals than times with frequent reversals. Published geomagnetic paleointensity data from the CNS are highly scattered suggesting that additional studies are required. Here we present new paleointensity results from 18 sites collected from the lower oceanic crust of the Troodos ophiolite, Cyprus (92.1 Ma old). Together with recently published data from the Troodos upper crust we obtain three independent palcointensity time-series. These sequences reveal quasi-cyclic variations of intensities about a mean value of 54 +/- 20 Z Am(2), providing insight into the fluctuating nature of the Cretaceous magnetic field. Our data suggest the CNS field was both weaker and more variable than predicted by geodynamo simulations. The large amplitudes of these variations may explain the wide range of dipole moments previously determined from the CNS. (c) 2007 Elsevier B.V. All rights reserved.