TY - JOUR TI - Equatorial paleomagnetic direction and paleointensity studies on lava flows from Galapagos for the Pliocene-Pleistocene DO - https://doi.org/doi:10.7282/T3VT1Q5F PY - 2014 AB - The current geomagnetic field (GMF) of the Earth is mostly geocentric dipolar with directions on the equatorial regions being horizontal and on the polar regions being vertical, while the field intensities in polar regions (~60 μT) are about twice as much as in equatorial regions (~30 μT). Previous time average field initiative (TAFI) studies suggested that the average directions of the geomagnetic field for the Pliocene- Pleistocene time period (0-5 Ma) coincide with the geocentric axial dipole (GAD) model predictions very well. However, both of the average paleointensities from the equatorial and the polar regions were about 30 μT, which did not agree with the GAD model. In this dissertation, I study the paleomagnetic directions and paleointensities recorded in the lava flows from Galapagos Islands, which are around 1° South of the Equator. The paleomagnetic directions from Galapagos coincide with the GAD model very well. In order to acquire reliable paleointensities, I develop a comprehensive BZF (back-zeroforth) experiment protocol along with a multidomain correction technique. The resultant equatorial paleointensities from Galapagos are much lower than previous estimates, which suggest a major dipolar component for the GMF in the Pliocene-Pleistocene. KW - Geological Sciences KW - Paleomagnetism--Galapagos Islands KW - Lava flows--Galapagos Islands LA - eng ER -