Nizamettin Kazancı, Aysen Özgüneylioğlu, Salim M. Öncel, Mehmet Korhan Erturaç, Eren Şahiner
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引用次数: 0
Abstract
Mahkemağcin Underground City (MUC) is a four-floored rock-cut dwelling complex carved into ignimbrite tuffs of the Early-Middle Miocene age in central Anatolia. The whole interior of the complex is covered by a 1–5 cm thick alteration crust that is not detected in any cave or outcrop in the region. This crust is investigated using microscopy, scanning electron microscopy, X-ray diffraction and X-ray fluorescence analyses, and the results are discussed from the geomechanical point of view. The colour of the outer surface of the crust is black, which turns red inside and grades into pale yellow above the white parent rock. The compaction and solidity of the crust are relatively high, as much as double that of the parent rock. The crust seems to have prevented and/or significantly decreased the erosion of the surfaces of the room walls. Mineralogical and chemical analyses together with experimental studies on selected samples suggest that such a crust could have formed because of thermal alteration at high temperatures ca. 600–950°C. On examination of the heated samples, the main geochemical changes within heated rocks were (i) an increase in silica concentration by ca. 2%–3% and (ii) the disappearance of zeolites and sericites. Thermoluminescence dating of the crust revealed thermal resetting of quartz crystals within the ignimbrite tuff at 243 ± 260 CE. All the analytical methods applied to the site indicate that the crust was obtained intentionally, possibly by burning woods indoors, aiming to harden the wall surfaces, mainly by Galatian people of the early Medieval time.
期刊介绍:
Geoarchaeology is an interdisciplinary journal published six times per year (in January, March, May, July, September and November). It presents the results of original research at the methodological and theoretical interface between archaeology and the geosciences and includes within its scope: interdisciplinary work focusing on understanding archaeological sites, their environmental context, and particularly site formation processes and how the analysis of sedimentary records can enhance our understanding of human activity in Quaternary environments. Manuscripts should examine the interrelationship between archaeology and the various disciplines within Quaternary science and the Earth Sciences more generally, including, for example: geology, geography, geomorphology, pedology, climatology, oceanography, geochemistry, geochronology, and geophysics. We also welcome papers that deal with the biological record of past human activity through the analysis of faunal and botanical remains and palaeoecological reconstructions that shed light on past human-environment interactions. The journal also welcomes manuscripts concerning the examination and geological context of human fossil remains as well as papers that employ analytical techniques to advance understanding of the composition and origin or material culture such as, for example, ceramics, metals, lithics, building stones, plasters, and cements. Such composition and provenance studies should be strongly grounded in their geological context through, for example, the systematic analysis of potential source materials.