Delineation of the Acemhoyuk settlement mound in Turkey using 2-D and pseudo-3-D VLF imaging

Abstract

In this study, we aimed to determine the boundaries, locations, and depths of some buried archaeological remains of service buildings belonging to Hatipler Palace in Acemhoyuk Settlement Mound from the Assyrian Trade Colony Period (2000-1750 BC) using the very low frequency (VLF) method. After geophysical VLF measurements of the mound, the VLF tipper data were filtered, as is common practice, by Karous and Hjelt (K&H) and Fraser filters. The 2-D VLF inversion technique was also applied to the data, which is a relatively modern procedure for VLF. The 2-D resistivity models obtained after the inversion enabled the construction of 2-D and pseudo-3-D subsurface resistivity images. These imaging techniques revealed two main distinguishing zones of mud-brick walls and stone foundations (moderate resistive zones > 13-ohm m) and surrounding materials (relatively low resistivity zones < 8-ohm m). VLF images, additionally, showed boundaries between the moderate and low resistivity zones successfully. Iso-resistivity images for resistivity values greater than 13-ohm m representing walls are also presented in this study. This imaging method clearly exposed building walls from the third level of the mound. Images obtained for the Acemhoyuk mound site with the VLF method allowed nondestructive excavation, and the images suggest new excavation locations for Hatipler Palace buildings, which is one of the most prominent buildings at this site. Our results also revealed that presenting the 2-D inverted VLF data as 2-D and pseudo-3-D images is a successful tool for subsurface imaging.