First archaeomagnetic secular variation curve for the Iberian Peninsula: Comparison with other data from western Europe and with global geomagnetic field models

Abstract

[1] A first secular variation (SV) curve for the Iberian Peninsula was computed by hierarchical Bayesian method using a total of 134 archaeomagnetic directions with ages ranging from À775 to 1959 A.D. A general agreement is observed between the Iberian curve and the French and German SV curves, although some interesting differences were found, such as the occurrence of lower inclinations between the 11th and 14th centuries in the Iberian curve. The analysis of these three reference curves indicates that SV in western Europe is characterized by three major directional changes at À125, 200, and 1350 A.D. It is suggested that these cusps are regional features of the geomagnetic field. The Iberian curve has been compared with the predictions of the Jackson, CALSK7K.2, and Hongre global models. Despite large differences recognized between these models, even for the dipolar terms, they predict reasonably well the Iberian archaeomagnetic SV.

A Comparison of Radiocarbon and Archaeomagnetic Dating from an Archaeological Site in Spain

“…A Bayesian statistical approach was adopted both for constructing the reference SV curves and calculating the archaeomagnetic date (Lanos 2004;Gómez-Paccard et al 2006) using the RENCURVE and RENDATE software. Probability density functions (PDF) are generated for both the declination and inclination values, which are then combined to give the overall PDF (Figure 6).…”

“…One example of this is in Spain and Portugal, where for the first time SV curves are sufficiently developed to be used for dating. Recently, Gómez-Paccard et al (2006) proposed reference SV curves for the Iberian Peninsula (the westernmost part of mainland Europe, which includes Spain, Portugal, Andorra, and Gibraltar; Figure 1). The curves are based on 134 directional data (declination and inclination) from sites in Spain, France, and Morocco, obtained from heated archaeological features (kilns, furnaces, and burnt horizons).…”

Directional changes of the geomagnetic field in West Africa: Insights from the metallurgical site of Korsimoro

“…Although from a distant region, the Balkan curve is the most complete and detailed paleosecular variation curve. Additionally the Spanish reference curve of Gomez-Paccard et al (2006), located about 3000 km North of Burkina Faso, is presented as a green line. Available data from Northwest- Fig.…”

“…(For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.) ern Africa (Morocco) are also shown as white circles (Kovacheva, 1984;Thellier and Thellier, 1959;Najid, 1987;Casas et al, 2008;Gomez-Paccard et al, 2012).…”

“…The CALS3K.4 model as yellow line , the Balkan curve in red (Tema and Kondopoulou, 2011), and the Spanish curve of Gomez-Paccard et al (2006) as a green line. Available data from Northwestern Africa (Morocco) are also shown as white circles (Kovacheva, 1984;Thellier and Thellier, 1959;Najid, 1987;Casas et al, 2008;Gomez-Paccard et al, 2012). Marine sediment data from Cape Ghir (Bleil and Dillon, 2008) are indicated as blue circles.…”