THE ROLE OF CLAYS IN THE DECAY OF ANCIENT EGYPTIAN LIMESTONE SCULPTURES
THE ROLE OF CLAYS IN THE DECAY OF ANCIENT EGYPTIAN LIMESTONE SCULPTURES
复制标题
粘土在古埃及石灰石雕塑腐烂过程中的作用
DOI：
10.1179/019713697806373172
复制
发表时间：
1997
影响因子：
0.5
通讯作者：
W. S. Ginell
中科院分区：
文献类型：
--
作者：
C. Rodriguez;E. Hansen;E. Sebastián;W. S. Ginell
来自Naga el-Deir(阿比多斯/底比斯地区)的一种埃及石灰岩显示出持续恶化的问题，其典型形式是从20世纪初进行的考古调查中获得的Naga el-Deir石碑的表面继续剥落。以前对这种石灰岩类型的测试表明，存在氯化钠和硝酸钠。这些雕塑经过了浸泡在水中或用水禽涂抹的方式进行了处理和淡化，但腐烂过程并未停止，在储存多年后，表面石头的主要损失仍然明显。矿物学和岩石学数据(X射线衍射、扫描电子显微镜和光学显微镜)表明，这块石头含有很高比例的粘土(按重量计高达10%)。实验室口头测试表明，粘土集中在层理面上，是造成上述类型恶化的主要原因。通过一系列实验，包括干湿循环和相对湿度变化，热机械分析，以及用水和乙二醇进行加速腐蚀试验，证明了粘土矿物在这类石灰石腐烂中的作用。这项研究的一个结论是，在某些情况下，海水淡化程序可能比僵化的环境控制导致更多的恶化。另一个结论是，将劣化归因于盐类的存在可能是不够的，在对富含粘土的石灰岩进行淡化之前，应进行进一步的岩相学分析。可能稳定粘土结构的非常规方法(通过
One type of Egyptian limestone from Naga el-Deir (Abydos/Thebes region) exhibits an ongoing problem of deterioration typified in the form of continued delamination of the surface in a stela from Naga el-Deir acquired from archaeological investigations carried out in the early 20th century. Previous testing of this limestone type indicated the presence of sodium chloride and sodium nitrate. The sculptures have been treated and desalinated either by immersion in water or by aqueous poulticing, but the decay process was not halted, and major loss of surface stone was still noticeable after storage for a period of years. Mineralogical and petrographic data (x-ray diffrac- tion (XRD), scanning-electron microscopy (SEM), and optical microscopy) indicate that this stone has a high proportion of clays (up to 10% by weight). Lab- oratory tests suggest that the clays, concentrated along bedding planes, are largely responsible for the type of deterioration noted. The role of clay minerals in the decay of this type of limestone was demonstrated by performing a series of experiments, including wet- ting/drying cycles and relative humidity changes, thermomechanical analysis, and accelerated decay tests using water and ethylene glycol. One conclusion of this study is that in some instances, desalination procedures can induce more deterioration than can rigid environmental control. Another conclusion is that attribution of deterioration to the presence of salts may be insufficient, and further petrographic analysis should be initiated prior to desalination of clay-rich limestones. Unconventional methods for possible stabilization of the clay structure (by means of