New Paleomagnetic Secular Variation (PSV) data from Fish Lake, Utah, USA, along with previously published regional records, allow us to build an independently dated Western North America PSV stack (WNAM17) from about 35 to 15 ka that quantifies dating and paleomagnetic uncertainties. In February 2014, we recovered a composite 11-m-long...
Regeneration of the Earth’s magnetic field by convection in the liquid core produces a broad spectrum of time variation. Relative palaeointensity measurements in marine sediments provide a detailed record over the past 2 Myr, but an explicit reconstruction of the underlying dynamics is not feasible. A more practical alternative is...
The paleomagnetic history of the volcanic rocks of Easter
Island was investigated using standard paleomagnetic techniques.
The remanent magnetization of 673 specimens from the three volcanic
episodes recognized on the island were measured using a spinner
magnetometer. Inclinations, declinations and virtual geomagnetic
poles were calculated for each flow. The majority...
Investigations of the behavior of the geomagnetic field on geological timescales rely on globally
distributed data sets from dated lava flows. We present the first suitable data from the Arctic region,
comprising 37 paleomagnetic directions from Jan Mayen (71°N, 0.2–461 ka) and Spitsbergen (79°N, 1–9.2 Ma) and five paleointensity results....
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paleosecularvariation (PSV; e.g., Glatz-
maier et al., 1999; Bloxham, 2000).
[4] The GAD hypothesis predicts
During Ocean Drilling Program Leg 202, detailed shipboard paleomagnetic measurements at Sites 1233 and 1234 identified a reproducible high-resolution record of paleomagnetic secular variation (PSV) at each site. These records also contained evidence for three magnetic field excursions. This paper summarizes the complete paleomagnetic record from Site 1233 and the...
The issue of permanent nondipole contributions to the time-averaged field lies at the very heart of
paleomagnetism and the study of the ancient geomagnetic field. In this paper we focus on paleomagnetic
directional results from igneous rocks of the southwestern U.S.A. in the age range 0–5 Ma and investigate
both...
Large ignimbrite flare-ups provide records of profound crustal modification during batholith formation at depth. The locations of source calderas and volumes and ages of the eruptions must be determined to develop models for the tectonomagmatic processes that occur during these events. Although high-precision isotopic ages of the ignimbrites are critical,...
Investigations of the behavior of the geomagnetic field on geological timescales rely on globally
distributed data sets from dated lava flows. We present the first suitable data from the Arctic region,
comprising 37 paleomagnetic directions from Jan Mayen (71°N, 0.2–461 ka) and Spitsbergen (79°N, 1–9.2 Ma) and five paleointensity results....
Investigations of the behavior of the geomagnetic field on geological timescales rely on globally distributed data sets from dated lava flows. We present the first suitable data from the Arctic region, comprising 37 paleomagnetic directions from Jan Mayen (71°N, 0.2–461 ka) and Spitsbergen (79°N, 1–9.2 Ma) and five paleointensity results....
I derive probability densities for virtual geomagnetic pole( VGP) longitudes for a general statistical model of
local magnetic field variations. I show that even for very
simple statistically homogeneous models of secular variation,
the distribution of VGP longitudes is peaked 90° away
from the sampling longitude. Thus, when sites are...