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Emissions of seismic waves, sound waves and dust are among the principal environmental issues associated with quarrying activity near urban areas. Exploitation methods at a leucithic lava quarry in Monteporzio, Italy, involve drilling and blasting at some distance from the urban centre and the use of hydraulic hammers at closer range. Seismic impact has been monitored and experimental measurements also carried out on noise emissions from the crushing and treatment installations.The data is discussed in the light of current national and international regulations., Emissions of seismic waves, sound waves and dust are among the principal environmental issues associated with quarrying activity near urban areas. Exploitation methods at a leucithic lava quarry in Monteporzio, Italy, involve drilling and blasting at some distance from the urban centre and the use of hydraulic hammers at closer range. Seismic impact has been monitored and experimental measurements also carried out on noise emissions from the crushing and treatment installations.The data is discussed in the light of current national and international regulations.

Natural discontinuities are extremely important in the exploitaton of dimension stone because of two fundamental aspects which condition the method of exploitation: the stability of the rock face and the block yield. Proposed calculation methods are described and applied to two examples, an underground quarry and a typical open pit., Natural discontinuities are extremely important in the exploitaton of dimension stone because of two fundamental aspects which condition the method of exploitation: the stability of the rock face and the block yield. Proposed calculation methods are described and applied to two examples, an underground quarry and a typical open pit.

An integrated software package is presented which makes possible the assessment of different technical and economic alternatives for underground mining by modelling some of the processes involved, such as design of mining methods and production planning. The inputs are geostatistical numerical models of the orebody and outputs are orebody boundary parameters and short- and medium-term production planning. The package was developed using the general characteristics of the complex sulphide Neves Corvo cut-and-fill mine in Portugal, to which its application is described in detail, but as it is modular it can also be applied in other contexts., An integrated software package is presented which makes possible the assessment of different technical and economic alternatives for underground mining by modelling some of the processes involved, such as design of mining methods and production planning. The inputs are geostatistical numerical models of the orebody and outputs are orebody boundary parameters and short- and medium-term production planning. The package was developed using the general characteristics of the complex sulphide Neves Corvo cut-and-fill mine in Portugal, to which its application is described in detail, but as it is modular it can also be applied in other contexts.

A geostatistical block model of an underground rock salt mine in Sicily was constructed on the basis of the physical and chemical parameters that ultimately determine the type of end-product. Mining operations according to different selection strategies were simulated using the model and taking account of both technical and commercial constraints., A geostatistical block model of an underground rock salt mine in Sicily was constructed on the basis of the physical and chemical parameters that ultimately determine the type of end-product. Mining operations according to different selection strategies were simulated using the model and taking account of both technical and commercial constraints.

A procedure for calculating the recoverable reserves of stratified orebodies characterised by thin and irregular layers is described. The procedure consists of building a block model of the deposit through the conditioned multivarial geostatistical simulation of small areal units. The application of this procedure to the phosphate deposits in the N'Zeto region of the Popular Republic of Angola is also described., A procedure for calculating the recoverable reserves of stratified orebodies characterised by thin and irregular layers is described. The procedure consists of building a block model of the deposit through the conditioned multivarial geostatistical simulation of small areal units. The application of this procedure to the phosphate deposits in the N'Zeto region of the Popular Republic of Angola is also described.

Identification and evaluation of the ferromanganese-bearing encrustations and micronodules provided the means for constructing geochemical maps of Mn, Fe, Ni, Co, Cu, and of interpreting a complex metals history that, in addition to ferromanganese mineralisation, resulted in metal-bearing massive sulphides interpreted to be the outcome of ongoing hydrothermal activity. The Fe-Cu mineralisation is interpreted as being linked with the sulphides and the Mn-Ni-Co with ferromanganese-bearing encrustations and micronodules. In relation to the area where sulphides were discovered, the zoning of Mn and Fe supports the idea that encrustations and micronodules are also primarily of hydrothermal origin, however diagenetic processes may also have played a significant role., Identification and evaluation of the ferromanganese-bearing encrustations and micronodules provided the means for constructing geochemical maps of Mn, Fe, Ni, Co, Cu, and of interpreting a complex metals history that, in addition to ferromanganese mineralisation, resulted in metal-bearing massive sulphides interpreted to be the outcome of ongoing hydrothermal activity. The Fe-Cu mineralisation is interpreted as being linked with the sulphides and the Mn-Ni-Co with ferromanganese-bearing encrustations and micronodules. In relation to the area where sulphides were discovered, the zoning of Mn and Fe supports the idea that encrustations and micronodules are also primarily of hydrothermal origin, however diagenetic processes may also have played a significant role.