The joint application of electric and magnetic techniques for near-surface exploration represents a very useful tool for archaeological investigation and can provide a quantitative contribution to describe the spatial distribution of buried objects. In this work we show a new advanced tomographic approach, based on the parallel inversion of magnetic and electric observed data, aimed at the reconstruction of the subsoil of a still unexplored area of the archaeological site of Pompeii (Southern Italy). The survey was performed in collaboration with Pompeii's Archaeological Commission. The comparison between the results obtained from the tomographic inversions of both electrical and magnetic data was carried out in terms of the data inversions, which allowed us to obtain information about the location of the buried geophysical sources in the investigated subsoil. The results obtained seem to be in a good agreement, both for the position of the geophysical sources and for their dimensions. 相似文献
The implementation of a 3D Electrical Resistivity Tomography (ERT-3D) survey was carried out in El Pahñú archaeological site, Hidalgo State, Central Mexico. A combination of a new ERT arrays allowed studying the subsoil beneath the Main Pyramid built near the edge of a plateau, along with another important structure (the Tecpan), which was a smaller structure that lodged the governmental council in pre-Hispanic times. The recorded information was acquired through the combination of several electrodic designs: L-Corner (LC), Equatorial (Eq), and Minimum Coupling (MC). For the Main Pyramid, the electrodes were set up around the perimeter of the structure, since they were not permitted to be inserted over the edifice, thus preventing damages to the architectonic elements. The second structure allowed inserting electrodes on selected spots within the architectonic space. The combination of the different arrays made possible the acquisition of 1204 apparent resistivities beneath the Main Pyramid and 2460 resistivity data beneath the Tecpan. The apparent resistivity data were inverted to obtain a three dimensional display of the subsoil electrical resistivity beneath the archaeological structure. The interpreted resistivity model under the Main Pyramid displayed a highly resistive structure towards its northern face that could be associated with infill. Such material was employed by the ancient constructors to level the terrain close to the edge of the cliff. Another interesting anomaly was found towards the central portion of the structure that could be associated to a foundation offer. The interpretation of data beneath the Tecpan identified the structural foundations and other interesting anomalies related to the different occupational times. The investigation supported the archaeological investigation of the site, suggesting areas of potential geological risk and of archaeological interest. For example, the Main Pyramid presents serious stability problems, indicating that the infill has weakened, producing cracks threatening long-term pyramid integrity. 相似文献
Timber structures can be degraded during their life both by structural problems and by biological degradation factors like fungi and insects. The occurrence of those biodegradation agents could lead to a loss of their structural integrity, in the absence of appropriate maintenance. An early assessment of the decay is even more important when the wooden structures are part of historical buildings, in the interest of conservation of cultural heritage.
This article presents an application of microwave reflectometry for the in situ evaluation of timber structures. The measurement system allows detecting anomalies inside the material in a non-destructive and non-invasive manner.
The reflection coefficient is measured by means of a vector network analyzer (VNA) using a double-ridge antenna which transmits the continuous-wave (CW) microwave signal and receives the signal reflected by the material under investigation.
Measurements on laboratory models demonstrated the feasibility of the method. Results obtained on timber beam sections, compared with the findings of traditional investigation methodologies, demonstrate the potentiality of microwave reflectometry, suggesting its possible usefulness during the diagnostic phase as a non-invasive tool for preliminary screening. 相似文献
Energy-dispersive X-ray fluorescence (EDXRF) and lead isotope analyses were applied to 12 Western Zhou (1046–771 bc) bronzes unearthed from the Shuangyantang site in Wushan County, Chongqing (southwest China), to investigate their chemical compositions and possible mineral source(s). The results showed that (1) the investigated bronzes were mostly bronzes with low, common lead and (2) their lead isotopic values almost all fall into a relatively narrow range, suggesting possibly the use of raw materials from a common copper mine. The comparison between lead isotopic values for Shuangyantang bronzes and those already published for copper mines and other bronzes produced and used about at the same times leads us to believe that the Shuangyantang bronzes probably used the same copper ores as used in bronzes from the Peng and Jin states in Shanxi Province. However, it would not be possible at this point to come up with a clear idea of where exactly these copper ores may come from. Candidate copper mines might be the Tonglvshan mines in Hubei Province, the Zhongtiaoshan mines in Shanxi Province, or the Dajing copper mines in Inner Mongolia. 相似文献