Outlining the Problem

Contamination of fresh and underground waters, channges chemical and mineralogical composition of soils and stream sediments invoked by industrial and agricultural activities, pollution of the environment due to mining and ore processing, decay of cultural and historic monuments, destruction of recent building structures - all these various processes and many others have one common feature. They are result of weathering - a rate-limited non-equilibrium process - where the most important agent is water and the most important site of reactions is mineral- or rock-water interface.

The rate of the rock-water interaction and allied redistribution of elements affects many of the fundamental aspects of the human life. It plays critical role in, for example, the quality of the potable water, the development of soils and the distribution of plant nutrients within them, the integrity of underground waste repositories, buildings, waterworks, road constructions, in the genesis of many types of roks and ores, and in more global sense, the geochemical cycling of the elements.

It has been only in the last few decades, when the instrumentation for direct study of these interactions has been developed. During the same time, our changing understanding of geoprocesses eventuated in essential reconsideration of the importance of mineral-water and rock-water interactions within the global geochemical picture. Unfortunately, the potential existence of numerous possible mineral assemblages, and an infinite variety of fluid compositions reacting with them cause that full, detailed understanding and reliable prediction of mineral-water interaction remains still a great wish rather than reality, despite current advances in experimentation and modeling.

Weathering is known to have in numerous cases a disastrous impact on the environment and the human society living in it. The example of the most severe attack provoked by weathering are extensive earth- or rock displacements - avalanches, landslides etc. Each of these events has initiation mechanism specific to the available mineral assemblage of the rock, eventually formed by weathering, clay minerals type being the most important feature. Weathering products in mining and ore processing, in industrial dumps, road bodies and dam constructions can also affect their mechanical and chemical stability and represent therefore a threat to life safety, to environment quality and hence also to the economic stability.

Elements entering the aquatic systems come from many natural sources - from water-rock interaction, biodegradation of rocks or volcanic activity. However, man-induced introduction of potentially hazardous elements into surface waters and air pollution is becoming more and more significant. On local, regional, and even global scale, this can outweigh the natural input, sometimes considerably. Toxic (to man, animals, and plants) elements and compounds may be liberated in the ubiquitous aquatic phase, transported to another place, become scavenged or even accumulated. Their scavengers, on the other side, can be weathering products, too.

The release of hazardous elements and chemical species can result directly from mining and other industrial activities, from chemical weathering of waste derived from mining, quarrying, ore treatment, or fossil fuels combustion, dumped into landfills, mining heaps and other dump sites. Within aquatic systems, transport and possible redistribution are critically influenced by interactions with minerals, in particular with zeolites, clay minerals, Fe/Mn oxydohydroxides and other soil components.

Despite the immense amount of new data on redistribution of the elements within the Earth’s crust on micro- to global scale, great uncertainty still remains in mechanisms and rate controlling steps of these processes. Their high sensitivity to variations in experimental conditions and methods used is responsible for great differences between the results of various research centers, laboratories and scholars. To diminish such discrepancies is one of the principal tasks of this project.

Better understanding of the mentioned processes requires series of theoretical studies, laboratory experiments (carried out under similar or comparable conditions, with identical methods and instrumentation), and consequent field observations. The project will minister to coordination of these research activities. Results of the theoretical modelling and laboratory experimentation will be confronted with field observations, provided by the Applied Research Subgroup .

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