Earth's Crust

The Czech Geological Survey (CGS) studies the petrological, structural-tectonic, geochemical and geophysical processes related to the evolution of the Earth‘s mantle and crust. The acquired knowledge broadens the understanding of the geological structure and geological composition of individual areas of the Czech Republic, improves follow-up geological mapping methods, is used in conducting research projects, and provides high-quality information necessary for systemic decision-making of state authorities.

The research conducted by the CGS is largely funded by ongoing projects of the Czech Science Foundation (GACR) and other grant agencies. Geological mapping and interrelated regional geoscience research are key components of this research area. They provide new information on the geological structure and geological evolution of given areas and evaluate the environment in terms of hazards due to extreme geodynamic phenomena.

Basic research on the structure of the lithosphere serves as a basis for all aspects of subsequent applied research, such as 3D modelling of the structure of Earth’s crust or the study of material flows and fluid and heat transfer in the crust. The results of basic and applied research are successfully combined due to the wide range of specialization and high quality of CGS experts. One key task of the CGS is to maintain its expertise on the Czech Republic’s geological structure at the highest level in order to provide pertinent high-quality information within the scope of regional and applied research, necessary for the national geoinformation system, relevant databases, geotechnical companies and other industrial and construction entities. Current research into crustal structure and evolution is sub-divided into three main areas:

Geological mapping and regional geological research

Geological mapping and the interconnected regional geoscience research provide new information on the geological structure and evolution of given areas and evaluate the environment in terms of hazards due to extreme geodynamic phenomena. Compiling geoscience maps and regional research are among the main research priorities of the CGS and generate a broad database, which is linked with detailed research on exogenous and endogenous processes in the lithosphere as well as with developing methods for 3D modelling of the Earth‘s crust. Geological mapping provides a wide range of additional information and knowledge essential for environmental protection and allows for a greater understanding of geohazards. Newly acquired data on mineral resources, including their estimates, generate direct economic benefits as well.

Many geological and derived maps, focusing primarily on protected landscape areas and other places of public interest in the Czech Republic, were produced in the past few decades. Recently completed geological maps at 1:25,000 scale include important data for safeguarding the rock environment as well as mineral resources and groundwater. They also contain point data on the chemical composition of soils and major rock types. In addition to inorganic pollutants, polycyclic aromatic hydrocarbons, polychlorinated biphenyls and organochlorine pesticides are also monitored in soils near large agglomerations.

Basic regional geological research in the Bohemian Massif and Western Carpathians is closely linked to geological mapping and is conducted in cooperation with other geological institutes in the Czech Republic and abroad. The CGS staff provides land-use planning authorities with thematic geological maps and comprehensive assessments regarding land development and all geoscience issues. Completed geological maps have gradually been made available to the public on the map server since 2003.

The CGS is also engaged in long-term foreign projects, mainly involving foreign development cooperation. On an international scale, the acquired data serve as a basis for use in INSPIRE (standardized data for the European geospatial information infrastructure).

Deep radioactive waste repository in the Czech Republic

The Czech Republic has long been preparing the construction of a deep radioactive waste repository, which should be located in crystalline rocks that form a natural barrier along with other materials. The site selection and actual repository construction requires an extensive study of the rock environment as well as of the procedures and materials used, which is carried out in underground laboratories, for instance at the Bukov Underground Research Facility. The CGS has been conducting similar projects over the long term and is actively engaged in describing and classifying the geological environment for the future repository. In addition, the CGS provides data and 3D models for the siting of other nuclear facilities, such as the new nuclear units at the Dukovany Nuclear Power Plant. In these cases, the methods of 3D modelling and visualization of the Earth’s crust allow for the advanced use of multidisciplinary geological data, which will be applied to extrapolate the geological structure known from the surface to depths of several kilometres in newly created 3D geological models. Remotely sensed data, such as satellite and drone data, are used as well.

Radioactive Waste Disposal

Mankind has constructed underground mines since the early Middle Ages. Particularly in the last century, humans have increasingly located structures, repositories, deep producing/geothermal wells and so forth beneath the Earth‘s surface. The experience gained during all these activities shows that the rock environment is highly heterogeneous and that its use, while highly desirable in many cases, also carries many risks. Detailed knowledge of the structure of the Earth‘s crust is essential for using the rock environment in an effective as well as safe manner. Specifically, this involves defining the geometry of basic lithological units, the degree of homogeneity of individual rock blocks, and the course of fault structures and other tectonic elements. Without these data, it is impossible to outline the optimal use of the rock environment, to design subsurface structures based on an ideal geometry, or to dimension engineering barriers and objectively assess their safety. The most accurate representation of the geological setting, particularly of the tectonic structure, is a basic prerequisite for follow-up models, simulations (geomechanical, hydrogeological, etc.) and for planning underground workings.