عنوان

Archaeological sites as physicochemical systems:

Number

TLpq303795329

.Language of Text, Soundtrack etc

انگلیسی

Title Proper

Archaeological sites as physicochemical systems:

General Material Designation

[Thesis]

First Statement of Responsibility

K. M. Wilson-Yang

Title Proper by Another Author

Two studies

Subsequent Statement of Responsibility

G. Burns

Name of Publisher, Distributor, etc.

University of Toronto (Canada)

Date of Publication, Distribution, etc.

1989

Specific Material Designation and Extent of Item

1

Dissertation or thesis details and type of degree

Ph.D.

Body granting the degree

University of Toronto (Canada)

Text preceding or following the note

1989

Text of Note

Studies in two Ancient Egyptian sites, the tombs at Beni Hasan and the Tomb of Nefertari are presented. The wall paintings in the arid Beni Hasan tombs (Middle Egypt, circa 2180 B.C. to 1786 B.C.) are obscured by an ubiquitous, rock-like surface layer. An examination of historical and recent observations, presented here, has shown that the formation of this layer has accelerated over the past 150 years. The surface degradation process is investigated here through the analysis of authentic painted-wall fragments. X-ray photoelectron spectroscopy (XPS), light microscopy (LM), electron-probe microanalysis (EMPA), and proton-induced X-ray emission microprobe analysis (PIXE) were used to examine the surfaces of painted fragments and the fragments in cross-section. Three surface types were found by XPS: a surface dominated by carbonates, a surface dominated by silicates and a surface which is between these two extremes. It appears that surface layer development involves the adsorption of condensation on the painted surfaces in the present or absence of air-borne particulates. The condensate acts to dissolve the limestone-based substrate upon which the wall-paintings were applied. Results from surfaces cleaned by conservators on-site with HCl indicated that some paint layer removal and leaching of trace-metals from red pigment layers has occurred. The stability, from 1904-1987, of the Tomb of Nefertari (No. 66, Valley of the Queens, circa 1240 B.C.) is re-examined and the causes and rates of macroscopic change explored. Loss of large areas of the paint and plaster strata has slowed at least since 1971. However, paint layer deterioration in the form of flaking has been continuous. The Tomb's stability appears to be intimately connected to its internal climate. To investigate the internal climate, a series of approximately 12 000 temperature and humidity measurements were made in the closed Tomb using an automatic, computer-based hygrotthermograph. The yearly average temperature inside the unperturbed Tomb has been found to be 28.5 0.5C. The internal humidity data did not show the same degree of stability: the yearly average humidity is 7 2 g H2O/m or 25 6% RH at 28C. (Abstract shortened with permission of author.)

Archaeology

Chemistry

Pure sciences

Social sciences

G. Burns

K. M. Wilson-Yang

Electronic name

p

[Thesis]

276903

a

Y