Details

Autor(en) / Beteiligte

• Aguilar Reyes, B
• Goguitchaichvili, A
• Morales, J
• Garduno, V H
• Pineda, M
• Carvallo, C
• Moran, Tomas Gonzalez
• Israde, Isabel
• Rathert, Manuel Calvo

Titel

An integrated archeomagnetic and C super(14) study on pre-Columbian potsherds and associated charcoals intercalated between Holocene lacustrine sediments in Western Mexico: Geomagnetic implications

Ist Teil von

• Journal of geophysical research. Solid earth, 2013-06, Vol.118 (6), p.2753-2763

Erscheinungsjahr

2013

Link zum Volltext

Quelle

Wiley Blackwell Single Titles

Beschreibungen/Notizen

• The firm relationship between archeomagnetic samples and their absolute ages, which is usually determined or estimated using a variety of methods (archaeological context, thermoluminiscense, C super(14), etc.), is crucial in any archaeomagnetic investigation. In this paper, we report 18 successful (from 65 analyzed) archaeointensity determinations of high technical quality performed on specimens obtained from three fragments of pre-Columbian potsherds. These are unambiguously correlated with charcoal samples, as they were found together in three thin lacustrine sedimentary layers in western Mexico. Moreover, new radiometric results were obtained in this study from all charcoal samples (beta analytic) yielding ages of 1490 plus or minus 40, 1510 plus or minus 40, and 1580 plus or minus 40 BP. In addition, detailed magnetic measurements were carried out on all studied ceramic fragments. These rock magnetic experiments, which included low field susceptibility versus temperature, hysteresis, and first-order reversal curve measurements, indicate that the main magnetic carrier is Ti-poor titanomagnetite. The average archeointensity values per ceramic fragments obtained in this study are very similar in all three cases: 35.2 plus or minus 1.3 mu T (N=5), 36.8 plus or minus 1.6 mu T (N=6), and 37.2 plus or minus 3.4 mu T (N=7). This corresponds to an average intensity of 36.4 plus or minus 1.1 mu T and a virtual axial dipole moment value of 8.1 plus or minus 0.2 10 super(22) Am super(2), which is slightly lower than the present field strength, corresponding at an age interval between 640 and 430A.D. Although we detected some relationship between the Earth's magnetic field intensity and multidecadal climatic events, such observations can only be considered tentative at this stage. Key Points * Relationship between archeointensity and climate * Absolute Geomagnetic Intensity Variation over the last 2 Milenia * Archeomagnetic reference curve for Mesoamerica