Archeomagnetic Intensity Variations During the 6th Millennium BC in the Middle East: New Data from Yarim Tepe II (Northern Iraq)

Abstract:

During the seventies, Soviet archeologists conducted in Northern Iraq excavations of several ancient settlements dated from the Pottery Late Neolithic period (7th and 6th millennia BC). A very large collection of artifacts unearthed from these sites, in particular several thousands of well-documented pottery fragments, is now stored at the Archeological Institute in Moscow. We collected a time-sequential series of groups of potsherds from the multilayered settlement called Yarim Tepe II dated to the Halaf period (6th millennium BC). Each group comprises a minimum of 3 potsherds (up to 10) found within a same archeological layer, typically a thickness of about 20 cm. Altogether, the fragment groups encompass the entire 7-m thick stratigraphic sequence of Yarim Tepe II. We will present our first archeointensity results obtained using the experimental protocol developed for the Triaxe magnetometer, taking into account the effects of both the thermoremanent magnetization (TRM) anisotropy and the cooling rate dependence on TRM acquisition. The new data help to better constrain the geomagnetic field intensity variations in the Middle East during the 6th millennium BC. Thanks to the comparison with other datasets from Bulgaria and Syria, the new archeointensity results provide evidence for the occurrence of very rapid geomagnetic field intensity variations around 5500 BC.