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1.
Kurt Heinrichs 《Environmental Geology》2008,56(3-4):643-675
Studies of many years—combining in situ investigation and laboratory analysis—have provided comprehensive information on weathering damage on the rock-cut monuments in the ancient city of Petra in Jordan. These rock-cut monuments represent outstanding world heritage. Many hundred monuments were carved by the Nabataeans from bedrock about 2000 years ago. The awareness of increasing weathering damage on the monuments has resulted in international efforts towards their preservation. The damage diagnosis has addressed the complex mutual relationships between stone types, stone properties, monument exposure regimes, environmental influences, weathering phenomena, development and extent of weathering damage and weathering progression. The rocks were classified lithostratigraphically and petrographically. Results on weathering forms, weathering profiles and weathering products obtained from monument mapping, in situ measurements and laboratory studies revealed a complex diversity of weathering phemomena with respect to type and intensity. Damage categories and damage indices were used to create a reproducible quantitative rating of weathering damage. Detailed results on weathering forms allowed the characterization and quantification of weathering progression including weathering prognoses. Stone properties and states of weathering damage were jointly considered for the rating of the rocks’ susceptibility to weathering. The systematic evaluation of weathering damage and monument exposure regimes can enhance the assessment of weathering factors and processes. 相似文献
2.
陕南石煤储量大、分布广,开采和利用历史久远,因富含Se等微量元素而备受关注。为了研究陕南石煤中的元素对其分布区水中元素含量和富集程度的影响程度和影响机理,共采集并分析了岚皋县北部佐龙镇晚前寒武纪—早古生代石煤出露区和开采区的天然水样35个。研究结果表明:石煤分布区的水质大部分较好,参照国家生活饮用水标准(GB 5749—2006)和世界卫生组织饮用水卫生标准(WHO)可知适于饮用的水样占总水样的62.86%。其中以Se含量高为特征,有11个水样中的Se达到中国饮用天然矿泉水标准(GB8537—2018)规定的含量标准(10~50μg/L)。水样pH值为6.72~8.34,呈近中性或弱碱性;所有样品均为淡水,溶解性总固体平均值为39.22 mg/L;水化学类型主要以Ca-HCO3和Ca·Mg-HCO3为主;水化学成分主要受岩石风化控制,水中Se主要来源于石煤风化以及水-石煤相互作用导致的元素溶出,富硒石煤是当地水中Se元素的主要来源。 相似文献
3.
I˙stanbul, the capital of the east Roman, Byzantine and Ottoman Empires embraces two continents, one arm reaching out to
Asia, the other to Europe. It is therefore, a rich city in terms of monuments and historical cites. Shell limestones of Upper
Miocene age are used as building stone in the majority of the monuments in I˙stanbul because of their attractiveness, availability
and workability. The durability characteristics of the limestones are examined, and those factors that are responsible for
atmospheric weathering are discussed, in a humid and marine environment with important problems of urban pollution, specifically
due to traffic. In the present study weathering of the building stones were first examined in situ by macroscopic observations.
The weathering that developed as a result of environmental effects since this limestone was first used in historical monuments
has been affected 0.1–1.5 cm deep from the surface. The weathered facing stone of Şehzade Mehmed Mosque in I˙stanbul is undergoing
a program of progressive replacement. During this study, samples were taken from this monument where the shell limestone was
used. The stone surface was principally examined by means of Scanning Electron Microscopy (SEM). Petrographical and mineralogical
analyses were made by using optical microscopy and X-ray diffraction method. The physico-chemical properties of these rocks
control their weathering behaviour and reactivity. Major and trace element analyses and the effect of deterioration on the
physical properties of the limestones (unit weight, porosity and water absorption) have also been investigated. Studies on
the samples implies that weathering on the stone surface caused important variations on the physical characteristics of the
rock.
Received: 11 February 1998 · Accepted: 18 August 1998 相似文献
4.
Malgorzata Labus 《Environmental Geology》2008,54(2):283-289
The scope of the paper is an attempt at the identification of the weathering-resistance classes within clastic rocks by means
of analysis of capillary pressure saturation curves. The porosimetric parameters corresponding to the cementing character
and the grains’ mineralogical content are very important features of stone building materials, because of the weathering processes.
The analysed rocks were Polish sandstones and muddy sandstones used for building purposes, collected from different geological
units of Poland (i.e. Sudety Mts. Carpathian Mts. and Holy Cross Mts.) The results indicate the usefulness of sandstone materials
for building purposes. They could also be used in conservation procedures and for the reconstruction of existing buildings
and monuments. Basing on the parameterisation, with the van Genuchten function, of cumulative capillary pressure saturation
curves, it was possible to distinguish four groups of the sampled rocks. The lithological features and weathering sustainability
within the groups are quite uniform, what allow identifying the weathering resistance classes. Taking into account the complicated
nature of all the factors influencing weathering processes, it is supposed that the presented parameterisation could be a
useful tool for weathering-resistance classification of clastic rocks. The classification could be useful in building industry
and in conservation of historical stone monuments. 相似文献
5.
Wanja Wedekind Christian J. Gross Andreas Hoffmann Siegfried Siegesmund 《Environmental Earth Sciences》2018,77(21):735
Sandstones, clay in the form of bricks and laterite are the building materials used by the Khmer to construct the imposing and magnificent temples in Southeast Asia. Many of these monuments suffer from fracturing, sanding, contour scaling, crust formation and salt weathering. The affinity to weathering is closely connected to the type of material. Two sandstone types classified as feldspathic arenite and quartz arenite of Angkor as well as two arkosic sandstones from Thailand are described and investigated in this study. Important petrophysical properties determined for the different sandstones consist of hydric expansion, thermal expansion, pore radii distribution and ultrasonic velocity. Different investigations such as capillary water uptake, surface hardness, hygroscopic water sorption, and salt resistance tests were undertaken in the laboratory to characterize the various rock types. Observations and quantified damage mapping were done onsite at the Phnom Bakheng Temple. Contour scaling in the form of weathering crusts is one of the main deterioration features observable at the Angkor monuments. Comparisons are made between the building stone, the crust material from the Phnom Bakheng Temple and fresh stone material used for restoration. Significant differences in hydric and especially in thermal expansion of the crust and sandstone have been determined. The results seem to indicate that extensional processes occur, which can be considered a force for detachment (i.e., contour scaling, flaking). In an experimental trial, the hydric and thermal expansion of the weathering crust and the building stone was significantly reduced by using a weak acid for the crust and a swelling inhibitor for the original building stone. 相似文献
6.
Domenico Calcaterra Alessio Langella Roberto de Gennaro Maurizio de’ Gennaro Piergiulio Cappelletti 《Environmental Geology》2005,47(3):341-352
This paper reports novel data concerning the volcanic formation of the Piperno, a stone that has been used for a long time in the monumental architecture of Naples and the Campanian region (Southern Italy). A careful field survey of the outcrops or underground sites so far accessible allowed us to draw a lithostratigraphic reconstruction of the formation and enabled the recognition of the three main layers exploited in past centuries and which provided dimension stones for architectural and structural purposes. Petrophysical and mineralogical characterization also enabled us to discriminate the same layers previously identified. Different scoriae/matrix ratio, scoriae dimension and welding degree are the most peculiar features of these horizons. The combination of these three parameters, even though they did not affect the use of Piperno as dimension stone, somehow determined its variable susceptibility to the weathering agents. However, a linear relationship between the exposure time and the decay of the stone itself, at a parity of weathering intensity, was not observed. This assumption was proved by verifying that the specific layers of the volcanic sequence controlled the weathering degree of Piperno from monuments disregarding their age of emplacement. 相似文献
7.
Historical data on the temperature and precipitation data for London has been combined with output from the Hadley Model to estimate the climate of London for the period 1100–2100 CE. This has been converted to other parameters such as freeze–thaw frequency and snowfall relevant to the weathering of stone facades. The pollutant concentrations have been estimated for the same period, with the historical values taken from single box modelling and future values from changes likely given current policy within the metropolis. These values are used in the Lipfert model to show that the recession from karst weathering dominates across the period, while the contributions of sulphur deposition seem notable only across a shorter period 1700–2000 CE. Observations of the late seventeenth century suggest London architects witnessed a notable increase in the recession rate and attributed “fretting quality” to “smoaks of the sea-coal”. The recession rates measured in the late twentieth century lend some support to the estimates from the Lipfert model. The recession looks to increase only slightly, and frost shattering will decrease while salt weathering is likely to increase. 相似文献
8.
D. Dragovich 《Environmental Geology》1991,17(2):127-132
Qualitative evidence from monuments and buildings in industrialized countries indicates that rates of stone deterioration rise in the presence of urban and industrial pollutants. Measurements presented here on surface reduction of marble tombstones show that mean weathering rates have increased over the period 1885 to 1955. Weathering rates were lower before the establishment of sulfur dioxide-emitting plants. Marble weathering involved solution etching along grain boundaries and within individual grains, and proceeded by surface roughening and dislodgement of grains with little apparent accumulation of gypsum. Absolute surface reduction of marble was less than that recorded in industrial environments in Europe and North America. 相似文献
9.
硅酸盐岩风化对气候变化和构造运动的反馈对长尺度气候变化可能起到重要的调节作用,对该反馈过程的定量认识有助于更确切理解地球碳循环的运行规律。通常认为风化类型可分为两种,分别是供应限制和动力学限制。全球变暖可能促进了动力学限制流域的化学风化作用,然而,关于这方面的认识仍很有限。育空河流域是典型的动力学限制风化区域,研究育空河的风化对气候变暖的响应有助于深入认识气候和大陆风化之间的相互作用。正演模型是区分河流风化端元的重要手段,文章利用正演模型对育空河流域从1975年到2019年的主要离子组成的数据集进行分析,并获得了该流域在过去几十年的化学风化速率的变化趋势。结果表明,育空河水化学性质主要受到碳酸盐岩风化和硅酸盐岩风化控制,两者多年平均碳汇通量分别为2.1×1011 mol/yr和4.1×1010 mol/yr,处于世界主要大河碳汇通量的中间水平。更重要的是,在同一时期,伴随着2.2℃的温度增幅和13.7%的径流量增加,流域内的阳离子总通量增加了35.7%,其中硅酸盐岩和碳酸盐岩风化产生的阳离子通量分别增加了41%和35%,阳离子通量/风化速率对气候的敏感性与冰岛地区的研究结果符合的很好,与风化速率加快相对应的,硅酸盐岩风化碳汇通量相对增加了59.6%。尽管碳汇的增加在绝对通量上相比人类化石燃烧产生的碳排放通量微不足道,但是考虑到构造尺度内全球硅酸盐岩风化速率的增强,尤其是在较为寒冷的高纬度地区,额外的二氧化碳固定量可能对地球历史时期的全球气候产生重要影响。 相似文献
10.
岩石的长期风化作用会造成岩石表面的剥落,这将导致石质文物产生无可挽回的破坏。为了更好地保护它们,需要开展在相同风化环境下岩石风化剥落深度和相对风化速度及其与不同岩性关系的研究。本文以衢州古城墙通仙门的多块岩石砌块为研究对象,利用自制的测量仪器,对不同岩性岩石砌块风化剥落深度和风化速度进行了研究; 通过分析量测结果得出凝灰岩、砂岩、砾岩、含砾砂岩和粉砂岩相对灰岩的风化速度分别为0.005～0.059mm a-1、0.032～0.097mm a-1、0.004～0.058mm a-1、0.021～0.033mm a-1 和0.015mm a-1。研究结果表明:在相同的风化环境之中不同岩石砌块的风化速度从大到小排序为V砂岩V凝灰岩V含砾砂岩 V砾岩V粉砂岩V灰岩,即岩石抗风化能力从强到弱为:灰岩粉砂岩砾岩含砾砂岩凝灰岩砂岩。由此,为石质文物的长期保护以及制定相关的保护措施提供了重要的理论依据。 相似文献
11.
Weathering of marbles and granites in marine environment: petrophysical properties and special role of atmospheric salts 总被引：1，自引：0，他引：1
The aim of this paper was to study the weathering mechanism of marbles and granites exposed to the marine environment at
the Delos archaeological site. Alterations, as granular disintegration, contour scaling and alveolus formations, can be observed
either at the base of blocks and columns, or at the median-high zones of monuments. A white marble, which originated from
Naxos Island, had a weak porosity (0.2%). Its porous network was organized into two subnetworks of rectilinear and sinuous
cracks, which limited capillary transfer to ∼10 cm. The granite, which originated from Delos Island, had a relatively high
porosity (2.15%), and had a well-connected system of cracks and microporous zones of weathered minerals. This homogeneous
network allowed good capillary transfer for long distances (1–2 m). For the marble, as for the granite, evaporation occurred
mainly at depth in the stone, and encouraged its deterioration. This damage depends on the dissolution and crystallization
of salts, which occur in cycles. First, by the capillary transfer of water and salt from the ground, when the stones are located
near the sea. This processes can explain the deterioration of the marble and the granite bases, and the decay of granite on
all its surfaces. Second, by fixation of water vapor by sea salt deposited on the stone by wind. This phenomenon can explain
the degradations observed on the median-high parts of monuments in marble and granite, even though, for the granite, the first
mechanism was more active. 相似文献
12.
Moisture in stone material is the key factor for all stone deterioration processes and also in weathering of cultural heritage. With additional presence of salts in the material the situation gets even more critical. While the properties of pure salts with moisture are well known, knowledge about the interaction of salt mixtures with moisture is still poor. In different approaches the reactions of salt-contaminated stone material on changing moisture were tested in the laboratory. Experiments with different solutions in the Na-Mg-SO4-NO3-H2O system revealed interesting new results on the moisture behaviour of salt-contaminated samples. Theoretical considerations and computer simulations are helpful to interpret the data obtained, but are not yet sufficient to explain the real processes acting on site at the monuments. More encouraging to this fact are complementary studies on visible efflorescences in the same salt system. It is shown how by experimental approaches the understanding on salt-induced stone deterioration is strongly complemented. 相似文献
13.
K.R. Moore 《Geoarchaeology》2006,21(2):155-170
The Murrisk Peninsula in southwest County Mayo is a major target for gold exploration in Ireland. The most productive areas include the Cregganbaun Shear Zone and Cregganbaun Quartzite Belt on Croagh Patrick, both geologically related to Iapetus closure, and gold is concentrated in alluvial deposits of river systems draining these areas. A comparison of gold occurrences with the location of prehistoric stone monuments reveals that simple standing‐stone monuments, though isolated from other monument types, correlate with alluvial gold. South of the Murrisk Peninsula in Connemara, isolated standing stones are associated with a wide range of mineral resources and with other monuments. Dating of the stones relative to blanket‐bog expansion and coastal landform changes indicates that standing stones were raised as markers of gold placer deposits before a climatic deterioration at 1200 B.C. Late Bronze Age monuments with a ceremonial purpose are more complex and include stone alignments. © 2006 Wiley Periodicals, Inc. 相似文献
14.
Experimental and numerical study of hygro-thermo-mechanical properties of “Schilfsandstein” from Baden-Württemberg 总被引：1，自引：0，他引：1
J. Ožbolt G. Grassegger P. Van der Veken G. Periškić H.-W. Reinhardt 《Environmental Geology》2008,56(3-4):535-546
In the present paper the results of experimental and numerical investigations of hygro-thermo-mechanical properties of “Schilfsandstein” from Baden-Württemberg are presented and discussed. The aim of the study was to investigate the influence of extreme environmental conditions causing severe damage that can often be observed on various monuments during restoration and reconstruction process. In the experimental investigations the stone specimen was exposed to extreme hygro-thermal conditions, which caused significant damage (cracking). During the experiment the ultrasonic and acoustic emission analyses were performed. Subsequently, a 3D finite element analysis was carried out using a coupled hygro-thermo-mechanical model for stone. The experimental and numerical results indicate that wetting in combination with either decrease or increase of temperature lead to severe damage. The most critical locations for initialization of cracks are sharp spikes (notches), or acute angles that are inward or outward oriented (corners). Stiff but brittle layers, like late diagenetic iron cementations, might be a weak point for the initialization of crack. Furthermore, the bedding direction (anisotropy) seems to be a preferred direction for crack propagation. The results of the numerical analysis are in relatively good agreement with experimental observations. 相似文献
15.
Giuseppe Montana Luciana Randazzo Paolo Mazzoleni 《Environmental Earth Sciences》2012,67(4):1097-1110
Blackening and disaggregation of exposed surfaces of stone monuments are well-known effects of stone decay taking place in polluted urban environments all over the world. This paper aims to assess the contribution of natural and anthropogenic sources of total suspended particulate (TSP) causing permanent damage (black crusts) to the stone monuments of Catania (Sicily), one of the most popular ??cities of art?? of southern Italy. Atmospheric pollution of Catania, a typical Mediterranean coastal town, is mainly contributed by vehicle exhaust emissions rather than industrial ones. Episodically, the city also suffers gaseous and ash emissions (plumes) from the nearby Mount Etna volcano. Thus, to discriminate between natural and anthropogenic contributions to stone decay on Catania monuments, black crusts and TSP were sampled within the urban area and subjected to specific analytical procedures (optical microscopy, X-ray powder diffraction, Fourier transformed infrared spectroscopy, scanning electron microscopy equipped with energy dispersive spectrometry, ionic chromatography and dual inlet mass spectrometry). Mineralogical, chemical and isotopic characterization of black crusts and TSP provided new insights concerning the partition of sulfate sources in this particular urban context. The influence of Mount Etna emissions on both TSP and black crusts compositions was shown. Nevertheless, the key role of anthropogenic sources in the total sulfate budget was confirmed, while sea spray and volcanic emissions were found to make subordinate contributions. Quantitative data useful for the identification of the threshold pollution levels for preventive conservation of Catania monuments were obtained. 相似文献
16.
The investigated rock material belongs to the group of upper cretaceous quader sandstones which are very important construction stones in Poland and Germany. The mineral composition of the rocks is relatively uniform??they are quartzose sandstones. The most important feature is their good workability and comparatively high weathering resistance. Still, regardless of the apparent resemblance, the observations carried on buildings and monuments show differences in weathering processes. The undertaken test was an attempt to verify the proposed before rock classification, performed on the basis of parameterization of porosimetric cumulative intrusion volume curves. The aim of the experiment was the evaluation of the sandstone petrography (including the structure, texture and porosity of the rock) influence on the weathering process. The modelling of accelerated weathering was conducted in Chamber for Ageing Acceleration, where some weather circumstances were simulated (insolation, rain and frost). As the result of the weathering experiment it could be stated that the dominant mechanism of the sandstones deterioration was granular disintegration and weight loss as a consequence of sample destruction. The most important factor influencing rock deterioration is rock texture, especially the character of grain contacts. The effective porosity is a requisite of potential for the stone to take in and hold water, and hence of resistance to weathering. In case of silica-cemented sandstones, the deciding criterion influencing weathering resistance is pore structure. In case of sandstones with clay cement, the most important is mineral composition of the rock. 相似文献
17.
《Chemie der Erde / Geochemistry》2019,79(2):235-246
This research is focused on the composition of the sediments produced in volcanic islands when the climate does not favour weathering. The XRD mineralogy (bulk sample and fraction finer than 63 μm), petrography and geochemistry of a set of bedload stream and beach samples collected in the “old” Maio and the “young” Fogo islands of Cape Verde archipelago are used to investigate the compositional transformations promoted by exogenous processes during island denudation. The main factor responsible for the variability in sediment composition is the incorporation of biogenic material derived from the evolving shelves; it largely exceeds the effects of the exhumation of different volcanic and basement units. Given the arid climate (and steep land surface in Fogo), only the most labile components of basaltic rocks, such as volcanic glass, are decomposed. The incipient weathering and sorting processes are responsible for the depletion of Al in bedload deposits. The same happens with other elements usually regarded as non-mobile (namely, Nb, Th, REE, etc.), while Mg is concentrated. Thus, weathering indices grounded on the premise that “mobile” elements are lost and “non-mobile” elements are enriched via weathering are useless in Cape Verde bedload sediments. With time, weathering is able to promote Na leaching and the formation of secondary minerals, which tend to retain non-mobile elements released in the earlier stages of alteration (e.g., LREE, Th, Y, Nb, Ta etc.). Sorting processes are responsible for the selective removal of less-dense grains, explaining local differences between beach and stream deposits. Beach placers are enriched in augitic clinopyroxene (occasionally also in olivine in the Fogo island), and Sc, Cr and Co. Niobium and Ta must be hosted in fine-grained particles that are easily windblown and their abundances in dusts may reveal Cape Verde as a source of airborne material crossing the Atlantic Ocean. 相似文献
18.
Mauro F. La Russa Germana Barone Cristina M. Belfiore Paolo Mazzoleni Antonino Pezzino 《Environmental Earth Sciences》2011,62(6):1263-1272
Noto is an important Baroque urban center in south-eastern Sicily, which was completely reconstructed after the severe earthquake
of 1693. Most of its monuments and historic buildings were built in Pietra di Noto stone, a pale cream calcarenite, quarried
in outcrops located near the city. This stone, still currently used as building material, is undergoing many forms of alteration
and degradation, which cause significant damage to monuments. In this study, three commercial protective products were tested
on some Noto calcarenite samples from quarries, with the aim of assessing their protective effectiveness. In particular, petrographic
analyses by optical microscopy were carried out for textural characterization of the stone materials. Capillary water absorption,
porosimetric and colorimetric procedures, UV radiation and salt crystallization aging tests were performed to better evaluate
interactions between protective products and substrate. 相似文献
19.
Abstract: Sri Lanka has the richest archaeological sites in Asia. Jethawanarama Complex, one of the valuable sites in the country, is suffering from deterioration due to weathering. Monuments were built mainly from stones (granitic gneiss and marble) and clay bricks. The present study aimed to categorize weathering forms and interpret the recently-developing weathering processes. The growing of lichens on surfaces and the development of saline conditions are the major threats on the survival of monuments other than the typical weathering processes of tropical climates Morinite (NaCa2 Al2[PO4)]2[F,OH]5·2H2O) is identified as a weathering product of monuments and is generated from lichens. 相似文献
20.
Interest in the preservation of rapidly decaying monuments, especially in urban areas, has increased appreciably over the last three decades. A stone preservative can be defined as a chemical treatment, which, when applied to stone, combats the harmful effects of time and environment, thereby prolonging the life of a stone by either restoring its physical integrity or by inhibiting its decay. Any preservative applied to stone must not change the natural appearance or architectural value of the stone to any appreciable extent. There are two principal means by which stone can be preserved. One involves the formation of an outer stabilized zone around the stone; the other alters the chemical composition of the stone.A number of examples of stone preservation carried out on ancient monuments in the United Kingdom are taken to illustrate stone preservation methods. Their relative success is evaluated, and some more recent developments in stone preservation referred to. 相似文献