Random crustal magnetization and its effect on coherence of short-wavelength marine magnetic anomalies

R.J. Blakely

doi:10.1016/0012-821x(79)90064-5

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Random crustal magnetization and its effect on coherence of short-wavelength marine magnetic anomalies

R.J. Blakely

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Abstract

Recent studies of DSDP samples from layer 2A of oceanic basement have found complex magnetic stratigraphies that seem incompatible with the frequent existence of linear short-wavelength anomalies caused by palaeomagnetic field behavior. Statistical models are developed for the lateral variation of the average magnetization of layer 2A: a Poisson series for reversals of the earth's field and a stairstep random series for discrete magnetic units. It is shown with the power-density spectra of these statistical models that lateral inhomogeneities must average out over distances of less than a few hundred meters. Specifically, individual magnetic units of the type seen at DSDP Site 332 cannot extend uniformly for distances greater than a few hundred meters.

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R.J. Blakely. 1979. Random crustal magnetization and its effect on coherence of short-wavelength marine magnetic anomalies. https://doi.org/10.1016/0012-821x(79)90064-5

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