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1.
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   

2.
An innovative approach to solve the problem of lowering water table was carried out in a quarry lake south of the city of Milan (northern Italy): the project, based upon pumping out water at a rate of 1,000 L/s can be considered a strategic medium to long-term solution to hinder the rise of groundwater level interfering with underground structures (foundation, construction, subway) in urban areas. The basic idea is to pump a high groundwater rate as close as possible to the stagnation point of the piezometric depression located in the city. After a pilot-test was carried out in November 1998, experimental activities started in July 2001 and lasted one year; water withdrawal was discharged into artificial channels used in agricultural practice. Maximum drawdowns measured in the quarry lake by the monitoring network resulted in more than 5 m, and a significant drawdown was registered up to 1.5 km of distance from the quarry in the important historical site of Chiaravalle Abbey, threatened by groundwater rise. The results of this pumping activity confirm the importance of the project, its lower cost compared with traditional solutions (such as drainage by wells) and remarkable effects on the improvement of surface water quality. A groundwater model was implemented to evaluate further scenarios of discharge rate and pumping location, too.  相似文献   

3.
Hydrogeology Journal - The significant increase in urbanization has resulted in greater use of the subsurface in urban planning and, therefore, increased interaction between groundwater and...  相似文献   

4.
Maps of factors contributing to groundwater contamination risk have been produced for a sector of the province of Milan to support decision-making in land planning and management.
Risk assessment has considered factors related to: natural vulnerability, hazard due to human activities and costs resulting from pollution. In order to evaluate existing hazard, a specific census was carried out over the area and industrial, agricultural and quarrying activities were mapped. Industrial activities were first divided into 4 groups according to national waste type regulation.
The number of data and the density of mapped factors necessitated the use of a land information system for data storage and management and map design.  相似文献   

5.
江苏省露采矿山环境保护(整治)模式及其适宜性评价   总被引:5,自引:1,他引:5  
通过对江苏省露天开采矿山环境保护和停采矿山环境整治的不同模式的特点、形成环境、采取的手段及取得的社会效益和经济效益的分析。结合其适宜性的评价论证,提出江苏省不同地理环境、经济基础和区位条件下的矿山环境保护(整治)模式,尤其是禁采区内停采、闭坑矿山环境整治模式和整治规划建议。土地资源紧缺的苏、锡、常地区的停采宕口。应充分利用土地置换模式,筹集资金,采取资源二次开发模式,将停采宕口成为土地开发利用新的组成部分;风景区内的采矿山宕口,拟采取景观再造模式,在恢复景区环境的基础上增加新景;大型停采矿区必须全面规划、综合整治;在采矿山地区,应引导企业规模开采,集约化经营,建立矿产资源工业园,并引进全新的矿山环境保护理念(京阳模式),采取生态采矿法开采;砖瓦粘土矿应边开采边复垦,保护耕地,达到矿业开发与环境保护协调发展的目的。  相似文献   

6.
Weathered facing stone of Durham Cathedral is undergoing a program of progressive replacement. The durability characteristics of the original stone and the replacement stone are examined, and those factors that are responsible for atmospheric weathering are discussed. Results of a field survey into relative weathering rates in the Durham area using local gravestones also are reported.  相似文献   

7.
Abstract

A new geodynamic model for the Sardinian segment of the Hercynian chain is presented. The improvement of knowledge regarding several geological, metamorphic, magmatic and geochronological aspects of the Sardinian Palaeozoic basement, mainly achieved in the last few years, allows us to propose a more complete picture of its evolution.

The occurrence of remnants of an oceanic suture along a major tectonic lineament in northern Sardinia, as well as the products of Ordovician calc-alkaline magmatism, testifies to the presence, during the Lower Paleozoic, of an ancient (Precambrian- Cambrian) oceanic domain and its consumption along an Andean- type subduction zone. The following Carboniferous continental collision caused crustal stacking with Barrovian metamorphism and southward-migrating deformation from the suture zone toward the foreland.

Early Carboniferous Culm-type facies sediments, deposited in the outermost zone of the chain, imply that continental collision took place earlier in the internal zone, from Late Devonian or Early Carboniferous.

The collisional orogenic wedge experienced ductile extension during the Late Carhoniferous as a result of gravitational collapse of the thickened continental crust.

Extensional tectonism enhanced the uplift of the chain and some regions underwent tectonic denudation or LP/HT metamorphism and somewhere anatexis. The emplacement of calc-alkaline batholiths and the development of Late Carboniferous - Early Permian molasse basins occurred during extension that prolonged throughout the Permian.  相似文献   

8.
The role of the major biogeochemical processes in Hg cycling at the sediment–water interface was investigated in the Grado Lagoon (Northern Adriatic Sea). This wetland system has been extensively contaminated from the Idrija Hg Mine (Slovenia) through the Isonzo River suspended load carried by tidal fluxes. Three approaches were used to study the sediment–water exchange of total Hg (THg), methylmercury (MeHg), reactive Hg (RHg) and dissolved gaseous Hg (DGHg): (1) estimation of diffusive fluxes from porewater and overlying water concentrations, (2) measurements of benthic fluxes using a deployed light benthic chamber in situ and (3) measurements of benthic fluxes during oxic–anoxic transition with a laboratory incubation experiment. The THg solid phase, ranging between 9.5 and 14.4 μg g−1, showed slight variability with depth and time. Conversely, MeHg contents were highest (up to 21.9 ng g−1) at the surface; they tended to decrease to nearly zero concentration with depth, thus suggesting that MeHg production and accumulation occur predominantly just below the sediment–water interface. Porewater MeHg concentrations (0.9–7.9 ng L−1, 0.15–15% of THg) varied seasonally; higher contents were observed in the warmer period. The MeHg diffusive fluxes (up to 17 ng m−2 day−1) were similar to those in the nearby Gulf of Trieste [Covelli, S., Horvat, M., Faganeli, J., Brambati, A., 1999. Porewater distribution and benthic flux of mercury and methylmercury in the Gulf of Trieste (Northern Adriatic Sea). Estuar. Coast. Shelf Sci. 48, 415–428], although the lagoon sediments contained four-fold higher THg concentrations. Conversely, the THg diffusive fluxes in the lagoon (up to 110 ng m−2 day−1) were one- to two-fold higher than those previously estimated for the Gulf of Trieste. The diurnal MeHg benthic fluxes were highest in summer at both sites (41,000 and 33,000 ng m−2 day−1 at the fishfarm and in the open lagoon, respectively), thus indicating the influence of temperature on microbial processes. The diurnal variations of dissolved THg and especially MeHg were positively correlated with O2 and inversely with DIC, suggesting an important influence of benthic photosynthetic activities on lagoon benthic Hg cycling, possibly through the production of organic matter promptly available for methylation. The results from the dark chamber incubated in the laboratory showed that the regeneration of dissolved THg was slightly affected by the oxic–anoxic transition. Conversely, the benthic flux of MeHg was up to 15-fold higher in sediments overlain by O2 depleted waters. In the anoxic phase, the MeHg fluxes proceeded in parallel with Fe fluxes and the methylated form reached approximately 100% of dissolved THg. The MeHg is mostly released into overlying water (mean recycling efficiency of 89%) until the occurrence of sulphide inhibition, due to scavenging of the available Hg substrate for methylation. The results suggest that sediments in the Grado Lagoon, especially during anoxic events, should be considered as a primary source of MeHg for the water column.  相似文献   

9.
This paper examines a case study regarding a site in the Murge karst (Apulia, southern Italy) where, in the course of time, anthropogenic activity has caused significant damage to the natural landscape and environment, also in terms of loss of human lives. The study site comprises the city of Bari and the neighbouring towns, belonging to the same catchment basin, which is characterised by a low-relief karst very rich in natural cavities and dry valleys, the latter locally called lame. From the second half of the 1500s until today, in the whole area, short rainfall storms (lasting less than 6 h) with disastrous and mortal consequences have been recorded many times. In the last decades, human activities, such as urbanization, stone clearing for agricultural purposes, quarrying and deforestation induced severe changes in the karst landscape causing the modification of the surficial and underground drainage. In particular, an examination is made of the factors causing the complete destruction of the “di Maso” Park on the night between 22 and 23 October 2005, in consequence of a high-intensity rainfall (152.6 mm in a 6-h period) accompanied by flash flooding. Finally, the need for a better understanding of natural processes and patterns in karst areas, and the interactions with human activities through to the development of environmental management systems ensuring further steps towards sustainable development is remarked.  相似文献   

10.
This paper describes the occurrence and significance of hydrocarbons present in two bituminous marl layers and one distinct gypsum layer from a Messinian sedimentary basin, where hypersaline conditions prevailed. Several new compounds were detected and tentatively identified: of these 20R and 20S 4α, 24-dimethyl-5α(H),14β(H),17β(H) and 20R and 20S 4β,24-dimethyI-5α(H),14β(H),17β(H) cholestanes; 4-methylspirosterenes; 4,4-dimethyl-5α(H),14β(H),17β(H) pregnanes and homopregnanes are discussed in this paper. Several of these compounds might be considered as biological markers for a (hyper)saline environment. The short side chain 4-desmethylsteranes, 5α(H),14β(H),17β(H), 5α(H),14β(H),17α(H) and 5α(H),14α(H), 17α(H) pregnanes and homopregnanes, are the most abundant compounds in the extract from the gypsum sample. It is suggested that in this case these compounds do not reflect the stage of diagenesis but are related to certain organisms exclusively occurring in hypersaline environments. In addition the very low pristane/phytane ratio, often considered as an indicator for anoxicity, could also be interpreted as a useful indicator for hypersalinity.  相似文献   

11.
12.
The State of Kansas, as an energy-producing and agriculture-based state, faces problems in production of natural resources and potential pollution from their production. To coordinate information on the exploration, production, and use of coal, nuclear, petroleum, natural gas, hydro, wind, geothermal, coalbed methane, biofuel, solar, and other energy resources, the Kansas Energy Council and the University of Kansas Energy Research Center were created. Water, surface and subsurface, is the other important and maybe the most important natural resource in the welfare of the state. To ease the problems of contamination, situations are monitored by regulatory agencies: the Kansas Corporation Commission, Kansas Department of Health and Environment, and Division of Water Resources of the Kansas Department of Agriculture. The Kansas Geological Survey (KGS) at the University of Kansas serves as the archive for energy and natural resource data and conducts research pertinent to the exploration and exploitation of mineral resources, including energy and water. The Kansas Energy Research Center coordinates and supports energy activities. The Kansas Water Office and the staff for the Kansas Water Authority are charged with water planning and preparing reports on water problems and possible solutions. The cost of preserving the environment in a relatively pristine state really is of no concern considering the possible consequences; living conditions should be preserved to assure future generations, a suitable, sustainable, stable environment. With all the dire predictions for the future and energy-producing and pollution problems, Kansas is a model state in this modern industrial age for protecting the environment and is a leader in conservation.
Daniel F. MerriamEmail:
  相似文献   

13.
In the southwestern part of Sardinia some subvolcanic andesitic bodies occur, related to rift structures. Weak alteration phenomena and the presence of pyrite disseminations led the authors to investigate the area through petrographical studies and geochemical prospecting of rocks and soils.The geochemical survey showed that, given the local morphological and climatic conditions, rock and soil sampling is well correlated; furthermore, correlations relating Cu with Ba and Sr proved effective in defining the anomalous areas.The main anomaly area found by these studies could represent a porphyry copper body.  相似文献   

14.
On June 19, 1996, an extremely heavy rainstorm hit a restricted area in the Apuan Alps (northwestern Tuscany, Italy). Its max intensity concentrated over an area of about 150 km2 astride the Apuan chain, where 474 mm was recorded in about 12 h (21% of the mean annual precipitation, with an intensity up to 158 mm/h). The storm caused floods and hundreds of landslides and debris flows, which produced huge damage (hundreds of millions of Euros), partially destroyed villages and killed 14 people. This paper reports the results obtained from a detailed field survey and aerial view interpretation. In the most severely involved area, 647 main landslides were investigated, mapped and related to the geologic, geomorphic and vegetational factors of the source areas. This was in order to define the influence of these factors and contribute to an evaluation of the landslide hazard in the study area. An assessment was also made of the total area and volume of material mobilised by landsliding. The study area, about 46 km2 wide, includes three typically mountainous basins, characterised by narrow, deep cut valleys and steep slopes, where many rock types outcrop. Most of the landslides were shallow and linear, referable to complex, earth and debris translational slide, which quickly developed into flow (soil slip–debris flow). Usually, they involved colluvium and started in hollows underlain by metamorphic rock (metasandstone and phyllite), often dipping downslope. Therefore, bedrock lithology and impermeability appeared to be important factors in the localisation of the landslide phenomena. The investigation of the geomorphic and land use features in the source areas also frequently highlighted a rectilinear profile of the slope, a high slope gradient (31–45°) and dense chestnut wood cover. In the area, about 985,000 m2 (2.1% of 46 km2) was affected by landsliding and about 700,000 m2 of this area was covered by chestnut forest. The landslides removed about 7000 trees. The volume of mobilised material was about 1,360,000 m3; about 220,000 m3 remained on the slopes, while the rest poured into the streams. In addition, about 945,000 m3 was mobilised by the torrential erosion in the riverbeds.  相似文献   

15.
16.
The monumental tomb of Jefferson Page, an officer in the American Navy, was built in 1899 and is located in the Non-Catholic Cemetery of Rome (Italy). This study presents complementary diagnostic studies characterizing the stone of the tomb and the weathering and decay phenomena it has undergone. The monument is made of a single type of whitish marble, variously veined and often covered with black patinas. Petrographic, isotopic and LA-ICP-MS analyses attribute the marble to the Carrara district. SEM/EDS and microbiological analyses indicate that the black patinas are due to cyanobacterial autotrophic and fungin heterotrophic colonization. Fourier-transform infrared spectroscopy revealed the presence of organic material on some portions of the tomb, due to undocumented restoration carried out with a mixture of marble powder and a polyester resin.  相似文献   

17.
An archaeometric study of the stone materials employed in the Late Baroque historical monuments of the ancient city centre of Catania was carried out. Lithological maps of a selection of monuments, transferred to a digital format, revealed that the stone materials are both magmatic and sedimentary rocks, the colours of which are matched in a peculiar type of bichromy. Particular attention focused on sedimentary rocks, which consist of various types of limestone quarried near the city of Syracuse (Hyblean Plateau, south-eastern Sicily). Carbonate rocks were characterised in terms of mineralogy, petrography and geochemistry, by studying rock samples from both monuments and historical extraction sites. Results showed that, although only one name was historically attributed to the above lithotypes (i.e. “Pietra di Siracusa‘’), they were quarried from many locations and, as they belong to various geological formations, they therefore exhibit great variety. In order to examine the durability of Hyblean limestones employed in works of cultural heritage interest, salt crystallisation tests were carried out according to standard procedure norms (UNI EN 12370 (1999) Determination of resistance to crystallisation of salts, 6p). Results are consistent with the forms of deterioration observed in the monuments, and highlight the close relationship between textural characteristics and damage. Our purpose is to provide a basic tool, which may be useful both for conserving monuments of cultural heritage and for their restoration.  相似文献   

18.
We report here, for the first time, on the new finding of extrusive calciocarbonatite (alvikite) rocks from the Pleistocene Mt. Vulture volcano (southern Italy). These volcanic rocks, which represent an outstanding occurrence in the wider scenario of the Italian potassic magmatism, form lavas, pyroclastic deposits, and feeder dikes exposed on the northern slope of the volcano. The petrography, mineralogy and whole-rock chemistry attest the genuine carbonatitic nature of these rocks, that are characterized by high to very high contents of Sr, Ba, U, LREE, Nb, P, F, Th, high Nb/Ta and LREE/HREE ratios, and low contents of Ti, Zr, K, Rb, Na and Cs. The O–C isotope compositions are close to the “primary igneous carbonatite” field and, thus, are compatible with an ultimate mantle origin for these rocks. The Sr–Nd–Pb–B isotope compositions, measured both in the alvikites and in the silicate volcanic rocks, indicate a close genetic relationship between the alvikites and the associated melilitite/nephelinite rocks. Furthermore, these latter products are geochemically distinct from the main foiditic-phonolitic association of Mt. Vulture. We propose a petrogenetic/geodynamic interpretation which has important implications for understanding the relationships between carbonatites and orogenic activity. In particular, we propose that the studied alvikites are generated through liquid unmixing at crustal levels, starting from nephelinitic or melilititic parent liquids. These latter were produced in a hybrid mantle resulting from the interaction through a vertical slab window, between a metasomatized mantle wedge, moving eastward from the Tyrrhenian/Campanian region, and the local Adriatic mantle. The occurrence of carbonatite rocks at Mt. Vulture, that lies on the leading edge of the Southern Apennines accretionary prism, is taken as an evidence for the carbonatation of the mantle sources of this volcano. We speculate that mantle carbonatation is related to the introduction of sedimentary carbon from the Adriatic lithosphere during Tertiary subduction.  相似文献   

19.
Traditional models of urban development are no longer adequate to describe current metropolitan transformations. These are now at the centre of a debate concerning management and administration. In Italy, delays in resolving problems of urban and metropolitan government, despite the legal framework provided by Law 142/90, have weighed heavily on the larger urban areas of the country: Rome, Naples, Milan, which have not been able to tackle the issue of metropolitan government. Recent legislation, while not providing a pre-defined institutional solution, allows separate administrative districts to collectively establish metropolitan institutions of `variable geometry'. The Milan urban area is not one city, but a system of mutually-dependent cities, linked to each other and the rest of the world by a transport network still requiring much investment. The vitality of its economic structure (especially its small firms) is held back by seriously inadequate infrastructure and low external economic efficiency. The provincial capital may boast `historic centrality' but the most interesting potential for development is to be found on the periphery and in the administrative districts immediately surrounding it, in the recovery of derelict industrial areas and dormitory towns established in the 1950s and 1960s, especially to the north. Recovery of derelict areas, green areas, and better transport links within the urban area and with the outside world are the key elements in the reorganization of `Greater Milan'. In this situation of rapid transformation the most appropriate political strategies involve negotiated planning. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

20.
The domestic and industrial waste water from most of the greater Athens, Greece area is discharged into shallow water at the upper end of the semi-enclosed Saronikos Gulf. The lack of circulation and excess organic matter has led to the formation of a rapidly expanding sludge field. Black anoxic sediments high in organic carbon now cover almost 9 sq km of sea floor and contain high concentrations of heavy metals. Maximum increases above background values range from 22× for mercury, 1500× for arsenic, 1200× for chromium, to 3000× for zinc. The principal sources of metals are 1) a fertilizer factory, 2) the Athens sewer outfall, and 3) the industries in eastern Elefsis Bay.  相似文献   

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