Rodygin S.A.

Geology

Lecture 1 Geology as a science, its main branches, connection with other sciences. The main stages in the development of geology

Lecture 2 Earth in world space, its origin. The composition and structure of the Earth

Lecture 3 General overview of geodynamic processes. exogenous processes. Weathering. Geological wind activity

Lecture 4 Geological activity of flowing waters

Lecture 5 Geological activity of groundwater. gravitational phenomena. Geological activity of ice

Lecture 6 Geological role of lakes and swamps. Geological activity of the sea

Lecture 7 Processes of internal dynamics (endogenous). earthquakes

Lecture 8 Vibrational movements of the earth's crust

Lecture 9 Fold-forming movements of the earth's crust

Lecture 10 Rupture-forming movements of the earth's crust. relief formation

Geology as a science, its main branches, connection with other sciences. The main stages in the development of geology

Geology as a science

A brief overview of the history of the development of geological knowledge

Questions for self-examination

Geology as a science

Geology(Greek "geo" - Earth, "logos" - doctrine) - the science of the Earth, its composition, structure and development, the processes occurring on it, in its air, water and stone shells.

The earth consists of several shells, the chemical composition, physical state and properties of which are different. Geology mainly studies the outer shell - the earth's crust or lithosphere (Greek "lithos" - stone) in close cooperation with other sciences - biology, soil science, geophysics, geography, etc. In geological research, first of all, the upper horizons of the earth's crust are studied in natural outcrops (outcrops of rocks from under sediments to the Earth's surface) and in artificial outcrops - mine workings (ditches, pits, shafts, wells). Geophysical methods are used to study the deep parts of the earth's crust .

At present, geology is a combination of many geological disciplines that emerged from it as a result of the in-depth development of individual branches of geological knowledge.

Geological research is carried out mainly on the stone masses that make up the earth's crust, called rocks. A special branch of geology is engaged in the direct study of rocks, which has emerged as an independent discipline and is called petrography(Greek "petros" - stone). Petrography describes the composition of rocks, their structure, conditions of occurrence, as well as their origin and changes caused by various factors.

Rocks are either loose accumulations or (more often) firmly soldered aggregates of individual solid particles (grains), each of which individually represents a chemically and physically homogeneous body. These constituent parts of rocks, often sharply different from each other and being very complex chemical compounds, are called minerals. The chemical composition, properties and origin of them studies mineralogy. The physical features of the internal structure of the substance of minerals, which is in a solid crystalline state, studies crystallography. The data of crystallography, mineralogy, petrography, in combination with the conclusions of other geological sciences, serve as the basis geochemistry. It establishes the patterns of distribution, combination and movement of individual chemical elements and their isotopes in the bowels of the Earth and on its surface. The disciplines listed above that study the material composition of the Earth have a related science - soil science, which considers the most superficial layer of the earth's crust, which has fertility and is called soil.

The sciences that consider the material composition of the Earth include the doctrine of minerals. This is a branch of geology that studies the conditions for the formation, distribution and change of mineral deposits in the earth's crust. Of these stand out ore(metals) and nonmetallic(mineral fertilizers, building materials, fossil fuels, etc.). This branch is of especially great practical importance.

Under the influence of internal (endogenous) forces associated with energy sources inside the Earth and external (exogenous) forces due to the solar energy received by the earth's surface, the earth's crust and the Earth as a whole are continuously changing, passing through a series of successive stages of development. The complex of sciences that study geological processes that change the face of the Earth combines dynamic geology. It considers the processes that cause changes in the earth's crust, the formation of the relief of the earth's surface and determine the development of the earth as a whole. A wide variety of objects of study led to the separation of such independent disciplines from dynamic geology as volcanology, seismogeology and geotectonics.

Volcanology studies the processes of volcanic eruptions, the structure, development and causes of the formation of volcanoes and the composition of the products they emit.

Seismogeology- the science of the geological conditions for the occurrence and manifestation of earthquakes.

Geotectonics (tectonics)- a science that studies the movements and deformations of the earth's crust and the features of its structure resulting from these movements and deformations.

The section of geology that considers the patterns of placement and combination of various rocks in the lithosphere, which determine its structure, is called structural geology.

The sciences that study external (exogenous) geological phenomena occurring in the surface parts of the earth's crust as a result of interaction with the atmosphere and hydrosphere belong to physical geography, although they are associated with dynamic geology. These sciences include: 1 - geomorphology - a science that studies the formation and development of landforms; 2 - land hydrology, exploring the water spaces of the Earth's continents (rivers, lakes).

The Earth has a very long and complex history of development, which is embodied in the rocks that consistently appeared in the bowels of the Earth and on its surface. Restoring the history of the Earth and explaining the reasons for its development is the subject of historical geology. This science establishes a connection between the development of the organic world and the development of the entire earth's crust. Its special disciplines are stratigraphy, paleontology, paleogeography.

Stratigraphy establishes the chronological sequence of the formation of rocks of the earth's crust, which serve as the main documents of the past. For this science, of particular importance is paleontology(Greek ??????? - ? jealousy, ????? - ? living; organism), which studies fossils enclosed in rocks and which are the remains of animals and plants that once existed. According to them, paleontologists restore the flora and fauna that existed on Earth in past geological epochs. Paleontology, based on the study of the remains of extinct animals and plants, establishes the age of rocks and makes it possible to compare heterogeneous strata of sedimentary formations that arose simultaneously. Geological chronology and periodization of geological history are based on the data of this science. It is also of great importance for clarifying the physical and geographical conditions, the situation of past geological epochs, which is the task paleogeography. The means for this clarification are the rocks and the fossils they contain.

The section of historical geology that studies the history of the development of the Earth in the last, so-called Quaternary period, stands out in a special area - Quaternary geology. The sediments formed in the Quaternary, as the youngest and most superficial, serve as a direct basis for human agricultural and engineering activities.

In the twentieth century, a new science began to develop especially intensively - geophysics, applying physical methods to study the earth's crust and the globe as a whole. The use of physical methods made it possible to clarify the structure of the deep bowels of the Earth.

The most important geological sciences dealing with the study of practical issues include the doctrine of minerals (see above), hydrogeology and engineering geology.

hydrogeology- the science of the origin, physical and chemical properties, dynamics and conditions of occurrence of groundwater, their manifestations on the earth's surface.

Engineering geology - the doctrine of the properties of rocks, those geological phenomena that arise as a result of construction and may have an impact on it.

Unlike most natural sciences, which widely use as the main method of research laboratory experience, Geology is a science in which the experimental research method has limited application. The main difficulty in applying the experiment in geology lies in incommensurability of scale time of geological processes with the duration of human life. Geological processes occurring in natural conditions last hundreds of thousands, millions and billions of years. Therefore, to study geological processes, it is used actualism method(French "actuelle" - modern). Its essence lies in understanding the past through the present, i.e. observations of modern geological processes. However, when applying this method, it must be remembered that the Earth itself, the physical and geographical conditions on its surface, as well as conditions in the bowels, climate, atmospheric composition, salinity of the seas and oceans, the organic world have been continuously changing and developing, therefore, the farther from us the past geological epoch, the less fully applicable to the knowledge of its geological conditions is the method of actualism.

The application of geological knowledge is not limited to the task of prospecting and exploration of mineral deposits, although this task is a priority. Geology is also of great importance in other sectors of the national economy: in construction, agriculture, health care, etc. The theoretical significance of geology is in understanding the structure of the Earth and the Universe, the development of the organic world. Geology has an ideological, philosophical significance, answering from scientific positions such burning questions as the origin of life on Earth, the course of the geological history of our planet, not only in the past, but also in the future, where knowledge of the laws of development of the earth's crust allows us to look.

“Geology is a way of life,” a geologist will most likely say when asked about his profession, before moving on to dry and boring formulations, explaining that geology is about the structure and composition of the earth, about the history of its birth, formation and patterns. development, about the once incalculable, and today, alas, "estimated" wealth of its bowels. Other planets of the solar system are also objects of geological research.

The description of a particular science often begins with the history of its origin and formation, forgetting that the narrative is full of incomprehensible terms and definitions, so it’s better to get to the point first.

Stages of geological research

The most general scheme of the sequence of studies into which all geological work aimed at identifying mineral deposits (hereinafter referred to as MPO) can be "squeezed" essentially looks like this: geological survey (mapping of outcrops of rocks and geological formations), prospecting , exploration, reserves calculation, geological report. Surveying, searching and reconnaissance, in turn, are naturally divided into stages depending on the scale of work and taking into account their expediency.

To perform such a complex of works, a whole army of specialists of the widest range of geological specialties is involved, which a real geologist must master much more than at the level of "a little bit of everything", because he is faced with the task of summarizing all this versatile information and, ultimately, come to the discovery of a deposit ( or make it), since geology is a science that studies the bowels of the earth primarily for the development of mineral resources.

Family of geological sciences

Like other natural sciences (physics, biology, chemistry, geography, etc.), geology is a whole complex of interrelated and intertwined scientific disciplines.

Directly geological subjects include general and regional geology, mineralogy, tectonics, geomorphology, geochemistry, lithology, paleontology, petrology, petrography, gemology, stratigraphy, historical geology, crystallography, hydrogeology, marine geology, volcanology and sedimentology.

Applied, methodological, technical, economic and other sciences related to geology include engineering geology, seismology, petrophysics, glaciology, geography, mineral geology, geophysics, soil science, geodesy, oceanography, oceanology, geostatistics, geotechnology, geoinformatics, geotechnology, cadastre and monitoring lands, land management, climatology, cartography, meteorology and a number of atmospheric sciences.

"Pure", field geology still remains largely descriptive, which imposes a certain moral and ethical responsibility on the performer, so geology, having developed its own language, like other sciences, cannot do without philology, logic and ethics.

Since prospecting and exploration routes, especially in hard-to-reach areas, are practically uncontrollable work, the geologist is always tempted by subjective, but competently and beautifully presented judgments or conclusions, and this, unfortunately, happens. Harmless "inaccuracies" can lead to very serious consequences both in scientific and production and material and economic terms, so a geologist simply does not have the right to deception, distortion and error, like a sapper or surgeon.

The backbone of geosciences is arranged in a hierarchical series (geochemistry, mineralogy, crystallography, petrology, lithology, paleontology and geology proper, including tectonics, stratigraphy and historical geology), reflecting the subordination of successively more complex objects of study from atoms and molecules to the Earth as a whole.

Each of these sciences branches widely in various directions, just as geology proper includes tectonics, stratigraphy, and historical geology.

Geochemistry

In the field of view of this science are the problems of the distribution of elements in the atmosphere, hydrosphere and lithosphere.

Modern geochemistry is a complex of scientific disciplines, including regional geochemistry, biogeochemistry and geochemical methods of prospecting for mineral deposits. The subject of study for all these disciplines are the laws of migration of elements, the conditions for their concentration, separation and redeposition, as well as the processes of evolution of the forms of finding each element or associations from several, especially similar in properties.

Geochemistry relies on the properties and structure of the atom and crystalline matter, on data on thermodynamic parameters that characterize part of the earth's crust or individual shells, as well as on general patterns formed by thermodynamic processes.

The direct task of geochemical research in geology is the detection of MPO, therefore, ore minerals are necessarily preceded and accompanied by geochemical surveys, the results of which are used to identify areas of dispersion of the useful component.

Mineralogy

One of the main and oldest sections of geological science, studying the vast, beautiful, unusually interesting and mysterious world of minerals. Mineralogical studies, the goals, objectives and methods of which depend on specific tasks, are carried out at all stages of prospecting and geological exploration and include a wide range of methods from visual assessment of the mineral composition to electron microscopy and X-ray diffraction diagnostics.

At the stages of survey, prospecting and exploration of MPO, studies are carried out in order to clarify the mineralogical search criteria and a preliminary assessment of the practical significance of potential deposits.

During the exploration stage of geological work and when assessing the reserves of ore or non-metallic raw materials, its full quantitative and qualitative mineral composition is established with the identification of useful and harmful impurities, the data on which are taken into account when choosing a processing technology or making a conclusion about the quality of raw materials.

In addition to a comprehensive study of the composition of rocks, the main tasks of mineralogy are the study of the regularities in the combination of minerals in natural associations and the improvement of the principles of the systematics of mineral species.

Crystallography

Once crystallography was considered a part of mineralogy, and the close relationship between them is natural and obvious, but today it is an independent science with its own subject and its own research methods. The tasks of crystallography consist in a comprehensive study of the structure, physical and optical properties of crystals, the processes of their formation and the features of interaction with the medium, as well as changes occurring under the influence of influences of various nature.

The science of crystals is divided into physical and chemical crystallography, which studies the patterns of formation and growth of crystals, their behavior under various conditions, depending on the shape and structure, and geometric crystallography, the subject of which is the geometric laws governing the shape and symmetry of crystals.

Tectonics

Tectonics is one of the core branches of geology, which studies in structural terms, the features of its formation and development against the background of different-scale movements, deformations, faults and dislocations caused by deep processes.

Tectonics is divided into regional, structural (morphological), historical and applied branches.

The regional direction operates with such structures as platforms, plates, shields, folded areas, depressions of the seas and oceans, transform faults, rift zones, etc.

An example is the regional structural-tectonic plan that characterizes the geology of Russia. The European part of the country is located on the East European platform, composed of Precambrian igneous and metamorphic rocks. The territory between the Urals and the Yenisei is located on the West Siberian platform. The Siberian Platform (Middle Siberian Plateau) extends from the Yenisei to the Lena. Folded areas are represented by the Ural-Mongolian, Pacific and partially Mediterranean folded belts.

Morphological tectonics, in comparison with regional tectonics, studies structures of a lower order.

The history of the origin and formation of the main types of structural forms of the oceans and continents is dealt with by historical geotectonics.

The applied direction of tectonics is associated with the identification of regularities in the distribution of various types of MPOs in connection with certain types of morphostructures and features of their development.

In the "mercantile" geological sense, faults in the earth's crust are considered as ore-supplying channels and ore-controlling factors.

Paleontology

Literally meaning "the science of ancient beings", paleontology studies fossil organisms, their remains and traces of life, mainly for the stratigraphic dissection of the rocks of the earth's crust. The competence of paleontology includes the task of restoring a picture that reflects the process of biological evolution on the basis of data obtained as a result of the reconstruction of the appearance, biological characteristics, methods of reproduction and nutrition of ancient organisms.

According to quite obvious signs, paleontology is divided into paleozoology and paleobotany.

Organisms are sensitive to changes in the physicochemical parameters of the environment, so they are reliable indicators of the conditions in which rocks were formed. Hence the close connection between geology and paleontology follows.

On the basis of paleontological research, together with the results of determining the absolute age of geological formations, a geochronological scale has been compiled in which the history of the Earth is divided into geological eras (Archaean, Proterozoic, Paleozoic, Mesozoic and Cenozoic). Eras are divided into periods, and those, in turn, are divided into epochs.

We live in the Pleistocene epoch (20 thousand years ago to the present) of the Quaternary period, which began about 1 million years ago.

Petrography

Petrography (petrology) deals with the study of the mineral composition of igneous, metamorphic and sedimentary rocks, their textural and structural characteristics and genesis. Research is carried out using a polarizing microscope in the beams of transmitted polarized light. To do this, thin (0.03-0.02 mm) plates (sections) are cut out of rock samples, then glued to a glass plate with Canadian balsam (the optical characteristics of this resin are close to those of glass).

Minerals become transparent (most), and their optical properties are used to identify minerals and their constituent rocks. The interference patterns in thin section resemble patterns in a kaleidoscope.

A special place in the cycle of geological sciences is occupied by the petrography of sedimentary rocks. Its great theoretical and practical significance is due to the fact that the subject of research is modern and ancient (fossil) sediments, which occupy about 70% of the Earth's surface.

Engineering geology

Engineering geology is the science of those features of the composition, physical and chemical properties, formation, occurrence and dynamics of the upper horizons of the earth's crust, which are associated with economic, mainly engineering and construction, human activity.

Engineering and geological surveys are aimed at performing a comprehensive and comprehensive assessment of geological factors caused by human economic activity in conjunction with natural geological processes.

If we recall that, depending on the guiding method, the natural sciences are divided into descriptive and exact, then engineering geology, of course, belongs to the latter, unlike many of its "comrades in the shop."

marine geology

It would be unfair to ignore the vast branch of geology that studies the geological structure and features of the development of the bottom of the oceans and seas. If you follow the shortest and most capacious definition that characterizes geology (the study of the Earth), then marine geology is the science of the sea (ocean) bottom, covering all branches of the "geological tree" (tectonics, petrography, lithology, historical and Quaternary geology, paleogeography , stratigraphy, geomorphology, geochemistry, geophysics, the doctrine of minerals, etc.).

Research in the seas and oceans is carried out from specially equipped ships, floating drilling rigs and pontoons (on the shelf). For sampling, in addition to drilling, dredges, clamshell-type grabs and straight-through tubes are used. With the help of autonomous and towed vehicles, discrete and continuous photographic, television, seismic, magnetometric and geolocation surveys are carried out.

In our time, many problems of modern science have not yet been resolved, and these include the unsolved mysteries of the ocean and its depths. Marine geology is honored not only for the sake of the science of "making the secret clear", but also to master the colossal mineral

The main theoretical task of the modern marine branch of geology remains the study of the history of the development of the oceanic crust and the identification of the main regularities of its geological structure.

Historical geology is the science of the patterns of development of the earth's crust and the planet as a whole in the historically observable past from the moment of its formation to the present day. The study of the history of the formation of the structure of the lithosphere is important because the tectonic shifts and deformations occurring in it appear to be the most important factors that determine most of the changes that took place on the Earth in past geological eras.

Now, having received a general idea of ​​geology, we can turn to its origins.

An Excursion into the History of Earth Science

It is difficult to say how far back the history of geology goes back thousands of years, but the Neanderthal already knew what to make a knife or ax from, using flint or obsidian (volcanic glass).

From the time of primitive man until the middle of the 18th century, the pre-scientific stage of accumulation and formation of geological knowledge lasted, mainly about metal ores, building stones, salts and underground waters. In the interpretation of that time, people started talking about rocks, minerals and geological processes already in ancient times.

By the 13th century, mining was developing in the countries of Asia and the foundations of mining and ore knowledge were emerging.

In the Renaissance (XV-XVI centuries), the heliocentric idea of ​​the world was established (J. Bruno, G. Galileo, N. Copernicus), the geological ideas of N. Stenon, Leonardo da Vinci and G. Bauer were born, and the cosmogonic concepts of R Descartes and G. Leibniz.

During the formation of geology as a science (18th-19th centuries), the cosmogonic hypotheses of P. Laplace and I. Kant and the geological ideas of M. V. Lomonosov and J. Buffon appeared. Stratigraphy (I. Lehmann, G. Fuchsel) and paleontology (J.B. Lamarck, W. Smith) were born, crystallography (R.J. Gayuy, M.V. Lomonosov), mineralogy (I. Ya. Berzelius, A. Kronstedt, V. M. Severgin, K. F. Moos, etc.), geological mapping begins.

During this period, the first geological societies and national geological surveys were created.

From the second half of the 19th to the beginning of the 20th century, the most significant events were the geological observations of Charles Darwin, the creation of the theory of platforms and geosynclines, the birth of paleogeography, the development of instrumental petrography, genetic and theoretical mineralogy, the emergence of the concepts of magma and the theory of ore deposits. Oil geology began to emerge and geophysics (magnetometry, gravimetry, seismometry, and seismology) began to gain momentum. In 1882 the Geological Committee of Russia was founded.

The modern period of development of geology began in the middle of the 20th century, when the science of the Earth adopted computer technologies and acquired new laboratory instruments, tools and technical means, which made it possible to begin the geological and geophysical study of the oceans and nearby planets.

The most outstanding scientific achievements were the theory of metasomatic zoning by D.S. Korzhinsky, the theory of metamorphism facies, the theory of M. Strakhov about the types of lithogenesis, the introduction of geochemical methods for prospecting for ore deposits, etc.

Under the leadership of A. L. Yanshin, N. S. Shatsky and A. A. Bogdanov, survey tectonic maps of the countries of Europe and Asia were created, and paleogeographic atlases were compiled.

The concept of a new global tectonics was developed (J. T. Wilson, G. Hess, V. E. Khain, etc.), geodynamics, engineering geology and hydrogeology stepped forward, a new direction in geology was outlined - ecological, which today has become a priority.

Problems of modern geology

Today, on many fundamental issues, the problems of modern science still remain unresolved, and there are at least one and a half hundred such issues. We are talking about the biological foundations of consciousness, the mysteries of memory, the nature of time and gravity, the origin of stars, black holes and the nature of other space objects. Geology also has many problems that have yet to be dealt with. This concerns mainly the structure and composition of the Universe, as well as the processes occurring inside the Earth.

Today, the importance of geology is growing due to the need to control and take into account the growing threat of catastrophic geological consequences associated with irrational economic activities that exacerbate environmental problems.

Geological education in Russia

The formation of modern geological education in Russia is associated with the opening in St. Petersburg of a corps of mining engineers (the future Mining Institute) and the creation of Moscow University, and the heyday began when in 1930 in Leningrad it was created, and then transferred to geology (now GIN AH CCCP ).

Today, the Geological Institute occupies a leading position among research institutions in the field of stratigraphy, lithology, tectonics and the history of the sciences of the geological cycle. The main areas of activity are related to the development of complex fundamental problems of the structure and formation of the oceanic and continental crust, the study of the evolution of rock formation of continents and sedimentation in the oceans, geochronology, global correlation of geological processes and phenomena, etc.

By the way, the predecessor of the GIN was the Mineralogical Museum, renamed in 1898 into the Museum of Geology, and then in 1912 into the Geological and Mineralogical Museum. Peter the Great.

Since its inception, the basis of geological education in Russia has been based on the principle of trinity: science - training - practice. This principle, despite perestroika upheavals, is followed by educational geology today.

In 1999, by decision of the boards of the Ministries of Education and Natural Resources of Russia, the concept of geological education was adopted, which was tested in educational institutions and production teams that "cultivate" geological personnel.

Today, higher geological education can be obtained in more than 30 universities in Russia.

And let go "for exploration in the taiga" or leave "to the sultry steppes" in our time is no longer as prestigious as it once was, the geologist chooses it, because "he is happy who knows the aching feeling of the road" ...

Geology is the science of the composition, structure and patterns of development of the Earth, other planets of the solar system and their natural satellites.

There are three main areas of geological research: descriptive, dynamic and historical geology. Each direction has its own basic principles and research methods. Descriptive geology deals with the study of the distribution and composition of geological bodies, including their shape, size, relationship, sequence of occurrence, and the description of various minerals and rocks. Dynamic geology considers the evolution of geological processes, such as the destruction of rocks, their transport by wind, glaciers, ground or ground water, the accumulation of precipitation (external to the earth's crust) or the movement of the earth's crust, earthquakes, volcanic eruptions (internal). Historical geology deals with the study of the sequence of geological processes in the past.

origin of name

Originally the word "geology" was the opposite of the word "theology". The science of spiritual life was opposed to the science of the laws and rules of earthly existence. In this context, this word was used by Bishop R. de Bury in his book Philobiblon (Love of Books), which was published in 1473 in Cologne. The word comes from the Greek γῆ meaning "Earth" and λόγος meaning "teaching".

Opinions differ about the first use of the word "geology" in the modern sense. According to some sources, including TSB, this term was first used by the Norwegian scientist Mikkel Pedersøn Escholt (M. P. Escholt, Mikkel Pedersøn Escholt, 1600-1699) in his book Geologica Norvegica (1657). According to other sources, the word "geology" was first used by Ulisse Aldrovandi in 1603, then by Jean André Deluc in 1778, and fixed the term by Horace Benedict de Saussure in 1779.

Historically, the term geognosia (or geognostics) has also been used. This name for the science of minerals, ores, and rocks was proposed by the German geologists G. Füchsel (in 1761) and A. G. Werner (in 1780). The authors of the term denoted by them the practical areas of geology that studied objects that could be observed on the surface, in contrast to the then purely theoretical geology, which dealt with the origin and history of the Earth, its crust and internal structure. The term was used in specialized literature in the 18th and early 19th centuries, but began to fall into disuse in the second half of the 19th century. In Russia, the term was preserved until the end of the 19th century in the titles of the academic title and degree "Doctor of Mineralogy and Geognosy" and "Professor of Mineralogy and Geognosy".

Branches of geology

Geological disciplines work in all three directions of geology and there is no exact division into groups. New disciplines appear at the intersection of geology with other fields of knowledge. The TSB provides the following classification: the sciences of the earth's crust, the sciences of modern geological processes, the sciences of the historical sequence of geological processes, applied disciplines, as well as regional geology.

Minerals are formed as a result of natural physical and chemical processes and have a certain chemical composition and physical properties.

Earth sciences:

• Mineralogy is a branch of geology that studies minerals, questions of their genesis, and qualifications. Lithology is the study of rocks formed in processes associated with the atmosphere, biosphere, and hydrosphere of the Earth. These rocks are not exactly called sedimentary rocks. Permafrost rocks acquire a number of characteristic properties and features, which are studied by geocryology.
• Petrography is a branch of geology that studies igneous and metamorphic rocks mainly from the descriptive side - their genesis, composition, textural and structural features, as well as classification.
• Structural geology - a branch of geology that studies the forms of occurrence of geological bodies and disturbances in the earth's crust.
• Crystallography - originally one of the areas of mineralogy, now more of a physical discipline.

Sciences of modern geological processes (dynamic geology):

• Tectonics is a branch of geology that studies the movement of the earth's crust (geotectonics, neotectonics and experimental tectonics).
• Volcanology is a branch of geology that studies volcanism.
• Seismology is a branch of geology that studies geological processes during earthquakes, seismic zoning.
• Geocryology is a branch of geology that studies permafrost rocks.
• Petrology is a branch of geology that studies the genesis and conditions for the origin of igneous and metamorphic rocks.

Sciences about the historical sequence of geological processes (historical geology):

• Historical geology is a branch of geology that studies data on the sequence of major events in the history of the Earth. All geological sciences, to one degree or another, are historical in nature, they consider existing formations in a historical aspect and are primarily concerned with clarifying the history of the formation of modern structures. The history of the Earth is divided into two major stages - eons, according to the appearance of organisms with solid parts, leaving traces in sedimentary rocks and allowing, according to paleontology, to determine the relative geological age. With the advent of fossils on Earth, the Phanerozoic began - the time of open life, and before that it was the Cryptotosis or Precambrian - the time of hidden life. Precambrian geology stands out as a special discipline, as it deals with the study of specific, often highly and repeatedly metamorphosed complexes and has special research methods.
• Paleontology studies ancient forms of life and deals with the description of fossil remains, as well as traces of the vital activity of organisms.
• Stratigraphy is the science of determining the relative geological age of sedimentary rocks, the division of rock strata, and the correlation of various geological formations. One of the main sources of data for stratigraphy is paleontological definitions.

Applied disciplines:

• Mineral geology studies the types of deposits, methods of their prospecting and exploration. It is divided into oil and gas geology, coal geology, metallogeny.
• Hydrogeology is a branch of geology that studies groundwater.
• Engineering geology is a branch of geology that studies the interactions between the geological environment and engineering structures.

Below are the remaining sections of geology, mainly standing at the junction with other sciences:

• Geochemistry is a branch of geology that studies the chemical composition of the Earth, processes that concentrate and disperse chemical elements in various spheres of the Earth.
• Geophysics is a branch of geology that studies the physical properties of the Earth, which also includes a set of exploration methods: gravity, seismic, magnetic, electrical, various modifications, etc.
• Geobarothermometry is a science that studies a set of methods for determining the pressure and temperatures of the formation of minerals and rocks.
• Microstructural geology is a branch of geology that studies the deformation of rocks at the microlevel, on the scale of grains of minerals and aggregates.
• Geodynamics is a science that studies the processes of the most planetary scale as a result of the evolution of the Earth. It studies the relationship of processes in the core, mantle and earth's crust.
• Geochronology is a branch of geology that determines the age of rocks and minerals.
• Lithology (Petrography of sedimentary rocks) is a branch of geology that studies sedimentary rocks.

The following branches of geology deal with the study of the solar system: cosmochemistry, cosmology, space geology and planetology.

Basic principles of geology

Geology is a historical science, and its most important task is to determine the sequence of geological events. To accomplish this task, a number of simple and intuitive signs of the temporal relationships of rocks have been developed since ancient times.

Intrusive relationships are represented by contacts between intrusive rocks and their enclosing strata. The discovery of signs of such relationships (hardening zones, dikes, etc.) unequivocally indicates that the intrusion was formed later than the host rocks.

Sexual relationships also allow you to determine relative age. If a fault tears rocks, then it was formed later than they.

Xenoliths and clasts enter the rocks as a result of the destruction of their source, respectively, they were formed earlier than the host rocks, and can be used to determine the relative age.

The principle of actualism postulates that the geological forces acting in our time worked similarly in former times. James Hutton formulated the principle of actualism with the phrase "The present is the key to the past."

The statement is not entirely accurate. The concept of "force" is not a geological concept, but a physical one, which has an indirect relation to geology. It is more correct to speak of geological processes. The identification of the forces accompanying these processes could be the main task of geology, which, unfortunately, is not the case.

The "principle of actualism" (or method of actualism) is synonymous with the method of "analogy". But the method of analogy is not a method of proof, it is a method of formulating hypotheses and, consequently, all regularities obtained by the method of actualism would have to go through the procedure of proving their objectivity.

At present, the principle of actualism has become a brake on the development of ideas about geological processes.

The principle of primary horizontality states that marine sediments are deposited horizontally when formed.

The principle of superposition lies in the fact that the rocks located in the bedding not disturbed by folding and faults follow in the order of their formation, the rocks lying above are younger, and those that are lower along the section are older.

The principle of final succession postulates that the same organisms are common in the ocean at the same time. It follows from this that a paleontologist, having determined a set of fossil remains in a rock, can find simultaneously formed rocks.

History of geology

The first geological observations are related to dynamic geology - this is information about earthquakes, volcanic eruptions, erosion of mountains, displacement of coastlines. Similar statements are found in the works of such scientists as Pythagoras, Aristotle, Pliny the Elder, Strabo. The study of the physical materials (minerals) of the earth dates back at least to ancient Greece, when Theophrastus (372-287 BC) wrote Peri Lithon (On Stones). During the Roman period, Pliny the Elder described in detail many minerals and metals, and their practical uses, and correctly identified the origin of amber.

Description of minerals and attempts to classify geological bodies are found in Al-Biruni and Ibn Sina (Avicenna) in the X-XI centuries. Al-Biruni's writings contain an early description of the geology of India, suggesting that the Indian subcontinent was once a sea. Avicenna offered a detailed explanation of the formation of mountains, the origin of earthquakes and other topics that are central to modern geology, and which provides the necessary foundation for the further development of science. Some modern scholars, such as Fielding H. Garrison, believe that modern geology began in the medieval Islamic world.

In China, the encyclopedist Shen Kuo (1031-1095) formulated a hypothesis about the formation of the earth: based on observations of fossil shells of animals in a geological layer in the mountains hundreds of kilometers from the ocean, he concluded that the land was formed as a result of mountain erosion and silt deposition.

During the Renaissance, geological research was carried out by scientists Leonardo da Vinci and Girolamo Fracastoro. They first suggested that fossil shells are the remains of extinct organisms, and also that the history of the Earth is longer than biblical representations. Niels Stensen gave an analysis of the geological section in Tuscany, he explained the sequence of geological events. Three defining principles of stratigraphy are attributed to him: the principle of superposition (English), the principle of primary horizontality of layers (English) and the principle of the sequence of formation of geological bodies (English).

At the end of the 17th - beginning of the 18th century, a general theory of the Earth appeared, which was called diluvianism. According to scientists of that time, sedimentary rocks and fossils in them were formed as a result of the global flood. These views were shared by Robert Hooke (1688), John Ray (1692), Joanne Woodward (1695), I. Ya. Scheikzer (1708) and others.

In the second half of the 18th century, the demand for minerals increased sharply, which led to the study of the subsoil, in particular, the accumulation of factual material, the description of the properties of rocks and the conditions for their occurrence, and the development of observation techniques. In 1785, James Hutton submitted a paper to the Royal Society of Edinburgh entitled The Theory of the Earth. In this article, he explained his theory that the Earth must be much older than previously thought, in order to allow enough time for the mountains to erode, and for the sediments to form new rocks on the sea floor, which in turn , were raised to become dry land. In 1795 Hutton published a two-volume work describing these ideas (Vol. 1, Vol. 2). James Hutton is often regarded as the first modern geologist. Hutton's followers were known as Plutonists because they believed that certain rocks (basalts and granites) were formed by volcanic activity and were the result of lava deposition from a volcano. Another point of view was held by the Neptunists, led by Abraham Werner, who believed that all rocks settled from the great ocean, the level of which gradually decreased over time, and explained volcanic activity by underground burning of coal. At the same time, Lomonosov’s geological works “A word on the birth of metals from the shaking of the Earth” (1757) and “On the layers of the earth” (1763) saw the light in Russia, in which he recognized the influence of both external and internal forces on the development of the Earth.

William Smith (1769-1839) drew some of the first geological maps and began the process of ordering rock strata by studying the fossils they contained. Smith drew up a "scale of the sedimentary formations of England". Work on the separation of the layers was continued by the scientists Georges Cuvier and A. Brongniard. In 1822, the Carboniferous and Cretaceous systems were distinguished, which marked the beginning of stratigraphic systematics. The main divisions of the modern stratigraphic scale were officially adopted in 1881 in Bologna at the 2nd International Geological Congress. The first geological maps in Russia were the works of D. Lebedev and M. Ivanov (map of Eastern Transbaikalia, 1789-1794), N. I. Koksharov (European Russia, 1840), G. P. Gelmersen (“General map of mountain formations of European Russia” , 1841). Silurian, Devonian, Lower Carboniferous, Liassic and Tertiary formations have already been marked on Koksharov's maps.

At the same time, the methodological foundations of such a division were still refined within the framework of several theories. J. Cuvier developed the theory of catastrophes, which states that the features of the Earth are formed in one catastrophic event and remain unchanged in the future. L. Buch explained the movements of the earth's crust by volcanism (the theory of "uplift craters"), L. Elie de Beaumont associated the dislocation of layers with compression of the earth's crust during cooling of the central core. In 1830, Charles Lyell first published his famous book Fundamentals of Geology. The book, which influenced the ideas of Charles Darwin, successfully contributed to the spread of actualism. This theory states that slow geological processes have taken place throughout the history of the Earth and are still happening today. Although Hutton believed in actualism, the idea was not widely accepted at the time.

For most of the 19th century, geology revolved around the question of the exact age of the earth. Estimates have ranged from 100,000 to several billion years. At the beginning of the 20th century, radiometric dating made it possible to determine the age of the Earth, an estimate of two billion years. The realization of this vast span of time has opened the door to new theories about the processes that have shaped the planet. The most significant achievement of geology in the 20th century was the development of the theory of plate tectonics in 1960 and the refinement of the age of the planet. The theory of plate tectonics arose from two separate geological observations: seafloor spreading and continental drift. The theory revolutionized the earth sciences. The age of the Earth is currently known to be about 4.5 billion years.

At the end of the 19th century, the economic needs of countries in relation to the subsoil led to a change in the status of science. Many geological surveys appeared, in particular the US Geological Survey (1879) and the Russian Geological Committee (1882). The training of geologists was introduced.

In order to awaken interest in geology, the United Nations proclaimed 2008 the "International Year of Planet Earth".

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Geology

Geology

a system of sciences about the history of the development of the Earth and about its internal structure. Main attention is paid earth's crust: its composition, structure, movement and distribution of minerals in it, especially in the upper part accessible to direct observation. Modern geology is subdivided into a number of sciences, directions and disciplines; some of them (eg. geophysics, exploring the physical fields of the planet) border on other natural sciences.
historical geology studies the process of formation of the Earth - both the planet as a whole and its shells. In turn, it includes: stratigraphy, which establishes the sequence of formation of rocks, as a result of which a geochronological scale is built; paleogeography(often referred to as a system of geographical sciences), which restores the landscapes of past geological eras; separates also Quaternary geology detailing the history quaternary period. Borderline with biology is paleontology, restoring the course of the evolution of life on Earth on the basis of the remains of fossil organisms and traces of their vital activity.
The material composition of the earth's crust is studied by the following sciences: mineralogy– the science of the origin and properties of minerals; petrography– the science of the origin and properties of predominantly igneous and metamorphic rocks; lithology dedicated to the study of sedimentary rocks. Borderline with chemistry is geochemistry- the science of the distribution and movement of chemical elements in the earth's crust and other shells of the Earth.
Geotectonics deals with the general patterns of the structure of the earth's crust and upper mantle (lithosphere), the origin and development of their constituent parts (tectonic structures), as well as the movement of the latter, which is the prerogative of a special area of ​​science - geodynamics.
A number of disciplines, along with the theoretical ones, are developing in depth the practical aspects of geology aimed at solving the national economy. and environmental issues. These include: hydrogeology studying groundwater; mineral geology studying the origin and distribution of deposits; engineering geology, in whose jurisdiction are the properties of soils and rocks, knowledge of which is necessary in construction and other types of households. activities. The synthesis of geological knowledge for a specific area is engaged in regional geology. It widely draws on the data of the science bordering on geography on the relief of the Earth - geomorphology.
Traditionally, geological research is based on direct field observations, which are then subjected to office and laboratory processing. Drilling works provide a unique material, especially in ultra-deep (more than 7 km) wells. Since the 1950s remote methods are widely used, including space imagery materials (see. remote sensing). The results of specialized and complex geological studies are presented in the form of maps, diagrams, profiles and text reporting materials. In recent decades, computer methods for processing and storing information have been widely used.
The origins of geology go back to ancient times and are associated with observations by ancient scientists (Strabo, Pliny, and others) of earthquakes, volcanic eruptions, and other natural phenomena. In the Middle Ages, the first descriptions and classifications of minerals appeared, judgments about the true nature of fossil shells as the remains of extinct organisms and about the long history of the Earth compared to biblical ideas (Leonardo da Vinci). As an independent branch of natural science, geology began to take shape in the 2nd half. 18th century and finally took shape in the beginning. 19th century, which is associated with the names of A. Werner, C. Hutton, M. V. Lomonosov, W. Smith and other prominent scientists. The works of C. Lyell laid the foundation for the development of the method of actualism, which made it possible to decipher the events of the geological past. In con. 19 - beg. 20th century in the leading countries of the world, geological surveys were established and systematic geological survey work began. In Russia, they are associated with the names of A. P. Karpinsky, F. N. Chernyshev, K. I. Bogdanovich, and others. At the same time, theoretical questions of geology continue to be developed by J. Hall, J. Dana, E. Og, E. Suess and others. Currently, geology has become one of the leading natural sciences, actively developing in most countries of the world.

Geography. Modern illustrated encyclopedia. - M.: Rosman. Under the editorship of prof. A. P. Gorkina. 2006 .

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Geology… Spelling Dictionary

- (Greek, from ge earth, and logos word). The science of the composition and structure of the globe and of the changes that have taken place and are taking place in it. Dictionary of foreign words included in the Russian language. Chudinov A.N., 1910. GEOLOGY Greek, from ge, earth, and logos ... Dictionary of foreign words of the Russian language

- (from geo ... and ... ology) a complex of sciences about the composition, structure and history of the development of the earth's crust and the Earth. The origins of geology date back to ancient times and are associated with the first information about rocks, minerals and ores. The term geology was introduced by Norwegian ... ... Big Encyclopedic Dictionary

GEOLOGY, the science of the material structure and composition of the Earth, its origin, classifications, changes and history concerning the geological development of the Earth. Geology is divided into several sections. Basic MINERALOGY (systematization of useful ... ... Scientific and technical encyclopedic dictionary

GEOLOGY, geology, pl. no, female (from Greek ge land and logos doctrine). The science of the structure of the earth's crust and the changes taking place in it. Historical geology (studying the history of the formation of the earth's crust). Dynamic geology (studying physical and ... Explanatory Dictionary of Ushakov

geology- and, well. gTologie f. 1. Physical geography; general geography. Sl. 18. Geology, the science of the globe, about the properties of mountains, about the changes in annual times. Corypheus 1 209. 2. The structure of the earth's crust in what l. terrain. ALS 2. Lex. Jan. 1803: geology; Sokolov ... ... Historical Dictionary of Gallicisms of the Russian Language

Modern Encyclopedia

Geognosia Dictionary of Russian synonyms. geology n., number of synonyms: 12 airgeology (1) ... Synonym dictionary

- (from geo ... and ... ology), a complex of sciences about the composition, structure and history of the development of the earth's crust and the Earth. The term "geology" was introduced by the Norwegian naturalist M. P. Esholt (1657). Geological data are widely used in ecology. Ecological ... ... Ecological dictionary

Geology- (from geo ... and ... ology), a complex of sciences about the composition, structure, history of the development of the earth's crust and the placement of minerals in it. Includes: mineralogy, petrography, geochemistry, mineral science, tectonics, hydrogeology, geophysics, ... ... Illustrated Encyclopedic Dictionary

Geology is a science that studies the composition, structure and patterns of the development of the Earth. Its essence is to consider the composition and structure of the lithosphere, geological processes by various methods using the methods and data of other disciplines.

History of science

There are different opinions about the time when geology appeared as a science.

In any case, the first observations that can be attributed to dynamic geology were made back in ancient times by such scientists as Aristotle, Pythagoras, Strabo, Pliny the Elder. Their works contain information about catastrophic geological processes (earthquakes and volcanic eruptions), as well as weathering phenomena (the erosion of mountains) and geomorphological processes (changes in coastlines).

The first mineralogical observations, namely descriptions of minerals and classifications of geological bodies, are contained in the works of Al-Biruni and Ibn-Sina of the 10th-11th centuries.

There is an opinion that modern geology appeared in the Middle Ages in the Islamic world.

During the Renaissance, the main discoveries in this area were made in Europe. During these times, Girolamo Fracastoro and Leonardo da Vinci were engaged in geological research. They made assumptions about a greater age of the Earth than given in Christian sources, and that fossil shells are the remains of organisms. Niels Stensen formulated three basic principles of stratigraphy, George Agricola laid the foundations of mineralogy.

At the end of the 17th century, thanks to the proposal of Martin Lister, the first geological maps and geological surveys appeared.

At the turn of the 17th and 18th centuries, a general theory of the Earth (diluvianism) was formulated, suggesting the formation of sedimentary rocks and fossils as a result of the global flood.

In the second half of the 18th century, the demand for resources increased significantly. This contributed to the enhanced study of the subsoil, as a result of which data were accumulated on the conditions of occurrence of rocks and their description, and new methods of study were developed. One of the most famous scientists of those times is James Hutton, who created the "Earth Theory". He suggested that the age of the planet is much older than previously thought. He is considered the first modern geologist. Two theories of rock formation emerged: plutonic (volcanic) and non-plutonic (sedimentary). In the same period, Lomonosov was engaged in geological research in Russia.

In the XVIII - XIX centuries. The first geological maps appeared in Russia.

The main question of the geology of the XIX century was the age of the Earth. In 1881, the modern stratigraphic scale was adopted at the 2nd International Geological Congress.

In the XX century. radiometric dating began to be used to determine the age of the planet.

In the USSR, the need for the development of geological knowledge arose immediately after the formation of the state, as industrialization began, which required a mineral resource base. Therefore, they began to study deposits of coal and hydrocarbons, and in the 20s. deposits of potassium salts, apatites and nephelines, copper were discovered. At the same time, the first geological map of the USSR was created.

In 1930, the Main Geological Administration was established. The Geological Committee, which supervised all the work, was transformed into the Central Research Geological Prospecting Institute, and then into the All-Union Geological Institute.

As a result of the work carried out by 1940, more than 65% of the territory was geologically mapped, the Urals became an industrial and raw material base, hydrocarbon deposits were discovered in Bashkiria and the Volga region, Siberia, the Caucasus, the Far East, Central Asia, Ukraine and other regions have changed significantly.

During the war years, the most intensive geological study of Kazakhstan was carried out under the leadership of K.I. Satpayev: deposits of manganese and chromium were discovered, and a rare metal industry was developed.

In 1946 the Ministry of Geology of the USSR was founded. In addition, new methods of studying the earth's crust have appeared: aerial photography, geophysical, drilling of reference wells. With their use, they discovered deposits of non-ferrous and rare metals, bauxites, coal, iron ores and hydrocarbons in Kazakhstan, coking coal, diamonds and iron ores in Yakutia, bauxites and hydrocarbons in Siberia, etc.

By 1967, the entire territory of the USSR had been geologically mapped, and more than 15,000 deposits had been explored.

Modern geology

From the definition of geology given above, it is easy to understand the objects of study of this science. Firstly, this is the structure and composition of natural bodies and the Earth, secondly, the processes in the depths and on the surface of the planet, thirdly, the history of its development, minerals.

The study is carried out in accordance with the system of levels of organization of mineral matter: mineral, rock, geological formation, geosphere, planet.

The tasks of geology can be divided into fundamental and applied.

The first follows from the definition of science. That is, this is the study of the structure, composition and patterns of development of the planet. The applied tasks of this science are as follows: the search for various minerals and the development of methods for their extraction, the study of geological conditions for the construction of structures, the protection of subsoil and their rational use.

Geology is characterized by a close connection between empirical and theoretical methods. The main one is geological survey. It consists in the study of rock outcrops and mapping. Many methods are borrowed from related sciences.

The work of a geologist

The curriculum for this specialty includes many engineering disciplines, as well as mathematics and geography. Naturally, the basis is geology and related sciences, such as mineralogy, geotectonics, petrography, etc. Among many other specialties, geology is usually distinguished by field practice in remote areas.

The profession of a geologist is in great demand in Russia, given its resource potential. These specialists work mainly in the mining sector. Field work is considered very difficult, given that many resources are developed in the far north, where workers are present on a rotational basis. Although there are options for laboratory and office work: engineering and geological surveys, 3D modeling, documentary work, etc.

Geological Sciences

Currently, geology is understood not only as a specific science, but also as a branch of knowledge that unites many sciences about the Earth. They can be classified according to the object of study.

About the earth's crust:

• mineralogy (studies minerals),
• crystallography (a section of mineralogy that deals with crystals, close to physical disciplines),
• petrography (subject - rocks),
• lithology (studies only sedimentary rocks),
• structural geology (considers the forms of occurrence of geological bodies),
• regional geology (studies the geological structure of individual sections of the earth's crust),
• petrophysics (explores the physical features of rocks, their mutual connections with the physical fields of the planet and among themselves),
• microstructural geology (considers microscopic deformations of rocks), geocryology (studies permafrost rocks),
• hydrogeology (studies groundwater).