Behaviour of the Earth's Palaeomagnetic Field from Small Scale Marine Magnetic Anomalies

摘要: CERTAIN areas of the ocean crust exhibit a high resolution recording magnetic field history. A recent survey1 Gorda-Juan de Fuca Rise area in North Pacific displays short wavelength (10 to 20 km), low amplitude (40 80 gamma) features superimposed upon larger scale (30 200 km, 800 anomaly pattern Heirtzler et al.2. Many these small anomalies form lineations which are parallel major al. Sequences characteristic patterns within intervals previously thought be constant polarity. We have identified two that we observed on profiles from South and South-east Indian Oceans. Because their global distribution, conclude due time variations Earth's field. That is, record either (less than 3 × 104 yr) polarity reversals or fluctuations intensity dipole moment, perhaps with periods greater