The presentation of the proposed material is based on the structure of various methods and principles for studying stratigraphy and paleogeography, proposed by researchers in different versions (Evdokimov, 1991; Gursky, 1979; Gursky et al., 1982, 1985; and others, table 1), in which they are grouped in accordance with the tasks to be solved.

The main method is natural-historical, which is a set of available modern methods, with the help of which comprehensive studies of the Earth are carried out, allowing to identify the state and processes of change in the geographical shell in time and space to explain their similarities and differences, the same type of relationship between the components of nature, to compare natural conditions and create forecasts for their development. Three main tasks lie at the heart of solving these problems:

1) the study of the natural environment of the past in time and space;

2) assessment of the state of geosystems of the current stage as a result of spatial and temporal development;

3) forecasting trends in the development of the natural environment based on their analysis in the past and present.

The solution of these problems finds its practical application in several aspects: geochronology (determining the age of events in the geological past), stratigraphy (splitting of strata), paleogeography (recreating the conditions for the accumulation of sediments and the development of natural components of the environment in time and space) and correlation (comparison of natural geological events as within individual regions, and significantly distant from each other - distant correlations) and is now based on the principles of actualism and historicism that arose after the emergence of uniformitarianism and catastrophism. It uses such scientific approaches as statistical, guiding forms, relics and exotics, paleontological complexes and evolutionary. The general methods or synthesis methods of scientific research are paleontological (biostratigraphic: floristic and faunistic), non-paleontological (geological-stratigraphic or lithogenetic) and physical. Obtaining factual material is carried out on the basis of the combined application of a number of private methods and analytical techniques. Private methods provide primary information, factual material, and common methods- allow to process already available information on their basis.

The collection and primary study of factual material is carried out in the field on the basis of aerial and geological surveys, drilling of wells, descriptions of geological objects (natural outcrops, outcrops of ancient rocks, products of volcanic activity, as well as artificial workings - cores of wells, pits, mines, quarries) , according to records and determinations by logging stations of physical properties rocks in wells, sampling and organic residues.

Subsequent processing of rocks is carried out in laboratory conditions and includes: technical processing of samples various types analyzes and subsequent microscopy (including photographing of objects), interpretation of aerial photographs and logging materials.

Generalization and analysis of the obtained data is carried out in office conditions using general scientific methods (modelling, system, logical, comparison and analogues) and techniques (mathematical, computer, tabular, as well as graphic in the form of diagrams, maps, profiles, punched cards, schemes, seismograms and etc.) processing the received information. The world's deepest well, the Kola well, was laid in 1970 and has a design depth of 15 km. Starting from 1961, American geologists, using a special vessel "Challenger", drilled 600 wells up to 500-600 m deep in different parts of the World Ocean bed. -24” passed through the lunar rocks to a depth of about 2 m, took samples that were brought to Earth and subsequently studied.

Any historical research, including historical and geological, is aimed at considering events in time, which requires establishing the chronology of these events. Chronology is a necessary and integral part of any geological and paleogeographic research. It makes it possible to arrange the events of the past in their natural sequence and establish their formal chronological relationships. Without chronology there can be no history (including geological history). But chronology is not history. According to I. Walter (1911), “only then does chronology turn into history, when the unity of great events from their beginning to their end finds expression in their presentation.”

To navigate in infinite set individual events of the past, it is necessary to establish not only their formal chronological relationships, but also their internal connections (chronological and spatial) with each other. Thus, their natural groupings can be identified, making it possible to outline the corresponding stages and boundaries of geological development, which form the basis of natural geological periodization.

The historical sequence of geological events is imprinted in the sequence of formation of the geological units (strata) that make up the earth's crust, which are studied by stratigraphy.

There is a close relationship between geochronology and stratigraphy. The task of geochronology is to establish the chronology of the events of the geological past of the Earth: its age (the initial time of its emergence as a planet of the solar system - the Proto-Earth; the age of the rocks formed during the evolution of the Proto-Earth and composing the earth's crust; chronological order periods of time during which the rock masses were formed. Since absolutely complete geological sections in the entire history of the planet do not exist at any point on the Earth due to the fact that periods of accumulation (accumulation) of sediments were replaced by periods of destruction and demolition (denudation) of rocks, many pages of the Earth's stone chronicle are torn out and destroyed. The incompleteness of the geological record requires a comparison of geological data over large areas in order to reconstruct the history of the Earth.

All these problems are solved on the basis of the methods of relative geochronology considered below. As a result, a geochronological (successive series of geochronological units in their taxonomic subordination) and stratigraphic (a set of common stratigraphic units arranged in the order of their sequence and taxonomic subordination) scales were developed with a number of corresponding units based on evolution organic world. Stratigraphic units are used to designate complexes of rock layers, and the corresponding geochronological units are used to designate the time during which these complexes were deposited.

When talking about relative time, geochronological units are used, and when talking about deposits that formed at a certain time, stratigraphic units are used.

The division and correlation of sections is carried out on the basis of criteria determined by the mineralogical and petrographic features of the layers, their relationships and conditions of accumulation, or by the composition of the remains of animal and plant organisms contained in the rocks. In accordance with this, it is customary to single out methods based on the study of the composition of the layers and their relationships (geological-stratigraphic methods) and those based on the paleontological characteristics of rocks (biostratigraphic methods). These methods make it possible to determine the relative age of rock layers and the sequence of events in the geological past (some younger or earlier, others older or later) and to correlate coeval layers and events.

Such a definition of the relative age of rocks does not give a real idea of ​​the geological age of the Earth, the duration of the events of the geological past and the duration of geochronological divisions. Relative geochronology makes it possible to judge only the sequence in time of individual geochronological units and events, but their true duration (in thousands and millions of years) can be established by geochronological methods, often called absolute age methods.

Thus, in geography and geology, there are two chronologies: relative and absolute. Relative chronology determines the age of geological objects and events relative to each other, the sequence of their formation and course using geological-stratigraphic and biostratigraphic methods. Absolute chronology establishes the time of occurrence of rocks, manifestations of geological processes and their duration in astronomical units(years) by radiometric methods.

In connection with the tasks set, private geographical and geological methods are combined into two large groups: absolute and relative geochronology.

The methods of absolute (radiometric, nuclear) geochronology determine quantitatively the absolute (true) age of geological bodies (strata, layers) from the time of their formation. These methods are of great importance for dating the oldest (including Precambrian) strata of the Earth, which contain very scarce organic remains.

Using methods of relative (comparative) geochronology, one can get an idea of ​​the relative age of rocks, i.e. determine the sequence of formation of geological bodies corresponding to certain geological events in the history of the Earth. The methods of relative geochronology and stratigraphy make it possible to answer the question of which of the compared deposits are older and which are younger without assessing the length of time of their formation and to what time interval the studied deposits belong, the corresponding geological processes, climate change, finds of fauna, flora, etc. .d.

Man has always been interested in everything that surrounded him: minerals, rocks, water, fire, air, plants, animals.

Ancient scientists collected facts, and then they systematized and established patterns. In their work, they used different ways and techniques, i.e. methods (from Greek word"methodos" - the path of research, theory, teaching).

Like all sciences, geography has special methods research. Let's consider some of them.

Geographic Description

This method was usually used by explorers, navigators, travelers who recorded the first information about open lands and the peoples inhabiting them. They tried to answer the questions: where is it located? What does it look like? What features does it have?

Now this method is widely used by participants in field studies and expeditions studying the relief, the World Ocean, the Earth's atmosphere, as well as the Arctic and Antarctica.

cartographic method

The map is a special source of geographical knowledge. It reflects and systematizes information obtained through observations and descriptions.

First geographic Maps appeared in ancient Greece in the VIII-VI centuries. BC uh... time went by. Maps were refined and improved. At present, computer maps are widely used.

Cartographers create various maps - geographical, climatic, minerals, etc. Thus, the cartographic method of research is the use of maps for scientific and practical knowledge the objects and phenomena depicted on them. It is an integral part of most geographic surveys.

Comparative geographical method

The comparative geographical method is one of the oldest in geography. It allows using comparison to identify the general and special in geographical objects, phenomena, processes.

Aerospace method

At present, this method has become one of the most important in geography. Observations and photographs from aircraft, satellites, space stations allow not only to compile very accurate maps, but also to find new mineral deposits, monitor human activity, pollution earth's surface, receive information about other planets of the solar system, about the Galaxy, the Universe.

Statistical Method

The statistical method is used to analyze statistical - quantitative and qualitative - data. Statistical accounting was carried out in ancient times. For example, in Ancient China population censuses were carried out. Currently, the statistical method is used in almost all industries. In geography, statistical material is presented in the text of textbooks, in maps, as well as in the form of diagrams, graphs, tables.

1. How did ancient people study the Earth?
2. What is the method of geographical description?
3. What role does the cartographic method play in our time?
4. What gives modern geography aerospace method?
5. Is it used per century computer technology methods of geographical research used by scientists of antiquity?

Earth is a unique planet: only on it does life exist. closely interrelated, they modify and complement each other. The processes occurring in nature and changing it are divided into physical and biological. Man has a huge impact on changing the face of the Earth.

They are called natural sciences. These include astronomy, physics, chemistry, geography, biology, geology, ecology.

It forms a group of interrelated sciences, the number of which is constantly increasing. There are two main sections: physical and socio-economic geography.

Special methods of geographical research are geographical description, cartographic, comparative geographic, aerospace and statistical methods.

Basic concepts and terms of the section:

• Live nature
• inanimate nature
• natural phenomena: physical, biological
• natural Sciences
• physical geography
• socio-economic geography
• methods of geographical research

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Methods for studying the structure of the Earth

Most of the particular sciences of the Earth are the sciences of its surface, including the atmosphere. Until a person penetrated deeper into the Earth further than 12 - 15 km (Kola ultradeep well). From depths up to approximately 200 km, the substance of the bowels is carried out in different ways and becomes available for research. Information about more deep layers obtained by indirect methods:

Registration of the nature of the passage of seismic waves different types through the earth's interior, by studying meteorites as relict remnants of the past, reflecting the composition and structure of the matter of the protoplanetary cloud in the formation zone of the terrestrial planets. On this basis, conclusions are drawn about the coincidence of the substance of meteorites of a certain type with the substance of certain layers. earthly depths. Conclusions about the composition of the earth's interior, based on data on the chemical and mineralogical composition of meteorites falling on the earth, are not considered reliable, since there is no generally accepted model for the formation and development of the solar system.

Earth structure

Probing the bowels of the earth with seismic waves made it possible to establish their shell structure and differentiation chemical composition.

There are 3 main concentrically located areas: core, mantle, crust. The core and mantle, in turn, are subdivided into additional shells that differ in physical and chemical properties (Fig. 51).

Fig.51 Structure of the Earth

The core occupies the central region of the earth's geoid and is divided into 2 parts. inner core is in a solid state, it is surrounded outer core, in the liquid phase. There is no clear boundary between the inner and outer nuclei, they are distinguished transition zone. It is believed that the composition of the core is identical to that of iron meteorites. The inner core consists of iron (80%) and nickel (20%). The corresponding alloy at the pressure of the earth's interior has a melting point of the order of 4500 0 C. The outer core contains iron (52%) and eutectic (liquid mixture solids) formed by iron and sulfur (48%). Small impurity of nickel is not excluded. The melting point of such a mixture is estimated at 3200 0 C. In order for the inner core to remain solid and the outer core to be liquid, the temperature in the center of the Earth should not exceed 4500 0 C, but not be lower than 3200 0 C. Ideas about the nature of terrestrial magnetism are associated with the liquid state of the outer core .

Paleomagnetic character studies magnetic field planets in the distant past, based on measurements of the remanent magnetization of terrestrial rocks, showed that over 80 million years there was not only the presence of a magnetic field, but also multiple systematic remagnetization, as a result of which the north and south magnetic poles of the Earth changed places. During periods of polarity reversal, there were moments of complete disappearance of the magnetic field. Therefore, terrestrial magnetism cannot be created by a permanent magnet due to the stationary magnetization of the core or some part of it. It is assumed that the magnetic field is created by a process called the self-excited dynamo effect. The role of the rotor (moving element) of the dynamo can be played by the mass of the liquid core, which moves with the rotation of the Earth around its axis, and the excitation system is formed by currents that create closed loops inside the sphere of the core.

The density and chemical composition of the mantle, according to seismic waves, differ sharply from the corresponding characteristics of the core. The mantle is formed by various silicates (compounds based on silicon). It is assumed that the composition of the lower mantle is similar to that of stony meteorites (chondrites).

The upper mantle is directly connected to the outermost layer, the crust. It is considered a "kitchen", where many of the rocks that make up the bark or their semi-finished products are cooked. It is believed that the upper mantle consists of olivine (60%), pyroxene (30%) and feldspar (10%). AT certain areas In this layer, partial melting of minerals occurs and alkaline basalts are formed - the basis of the oceanic crust. Through the rift faults of the mid-ocean ridges, basalts come from the mantle to the Earth's surface. But this is not limited to the interaction of the crust and mantle. The fragile crust, which has a high degree of rigidity, together with part of the underlying mantle forms a special layer with a thickness of about 100 km, called lithosphere. This layer rests on the upper mantle, the density of which is noticeably higher. The upper mantle has a feature that determines the nature of its interaction with the lithosphere: in relation to short-term loads, it behaves like a rigid material, and in relation to long-term loads, as a plastic one. The lithosphere creates a constant load on the upper mantle and, under its pressure, the underlying layer, called asthenosphere exhibits plastic properties. The lithosphere "floats" in it. Such an effect is called isostasy.

The asthenosphere, in turn, relies on deeper layers of the mantle, the density and viscosity of which increase with depth. The reason for this is the compression of rocks, which causes a structural rearrangement of some chemical compounds. For example, crystalline silicon in its normal state has a density of 2.53 g / cm 3, under the influence of increased pressures and temperatures, it passes into one of its modifications, called stishovite, the density of which reaches 4.25 g / cm 3. The silicates that form this modification of silicon have a very compact structure. On the whole, the lithosphere, asthenosphere, and the rest of the mantle can be considered as a three-layer system, each of whose parts is mobile relative to other components. The light lithosphere, which rests on a not too viscous and plastic asthenosphere, is distinguished by particular mobility.

The earth's crust, which forms the upper part of the lithosphere, is mainly composed of eight chemical elements: oxygen, silicon, aluminum, iron, calcium, magnesium, sodium and potassium. Half of the entire mass of the crust is accounted for by oxygen, which is contained in it in bound states, mainly in the form of metal oxides. Geological features the crust is determined by the joint actions of the atmosphere, hydrosphere and biosphere on it - these three outer shells of the planet. The composition of the bark and outer shells is continuously updated. Due to weathering and drift, the substance of the continental surface is completely renewed in 80-100 million years. The loss of matter on the continents is replenished by age-old uplifts of their crust. The vital activity of bacteria, plants and animals is accompanied by a complete change of carbon dioxide contained in the atmosphere in 6-7 years, oxygen - in 4,000 years. The entire mass of the hydrosphere (1.4 · 10 18 tons) is completely renewed in 10 million years. An even more fundamental circulation of matter on the surface of the planet proceeds in processes linking all the inner shells into a single system.

There are stationary vertical flows called mantle jets, they rise from the lower mantle to the upper and deliver combustible matter there. The phenomena of the same nature include intraplate "hot fields", with which, in particular, the largest anomalies in the form of the Earth's geoid are associated. Thus, the lifestyle of the earth's interior is extremely complex. Deviations from mobilist positions do not undermine the idea of ​​tectonic plates and their horizontal movements. But it is possible that in the near future a more general theory of the planet will appear, taking into account horizontal movements plates and open vertical transfers of combustible matter in the mantle.

The uppermost shells of the Earth - the hydrosphere and atmosphere - differ markedly from other shells that form the solid body of the planet. By mass, this is a very small part of the globe, no more than 0.025% of its total mass. But the significance of these shells in the life of the planet is enormous. The hydrosphere and atmosphere arose at an early stage of the formation of the planet, and perhaps simultaneously with its formation. There is no doubt that the ocean and atmosphere existed 3.8 billion years ago.

The formation of the earth proceeded in line with a single process that caused the chemical differentiation of the interior and the emergence of the precursors of the modern atmosphere and hydrosphere. At first, the proto-core of the Earth was formed from grains of heavy non-volatile substances, then it very quickly attached the substance, which later became the mantle. And when the Earth reached approximately the size of Mars, the period of its bombardment began planetosimalia. The impacts were accompanied by strong local heating and melting of the earth's rocks and planetosimals. At the same time, gases and water vapor contained in the rocks were released. And as the planet's average surface temperature remained low, water vapor condensed to form a growing hydrosphere. In these collisions, the Earth lost hydrogen and helium, but retained heavier gases. The content of inert gas isotopes in modern atmosphere allows you to judge the source that gave rise to them. This isotopic composition is consistent with the hypothesis about the impact origin of gases and water, but contradicts the hypothesis about the process of gradual degassing of the Earth's interior as a source of formation of the atmosphere and hydrosphere. The ocean and atmosphere certainly existed not only throughout the entire history of the Earth as a formed planet, but also during the main phase of accretion, when the proto-Earth was the size of Mars.

The idea of ​​impact degassing, considered as the main mechanism for the formation of the hydrosphere and atmosphere, is gaining more and more recognition. laboratory experiments the ability of impact processes to release appreciable amounts of gases, including molecular oxygen, from terrestrial rocks was confirmed. And this means that a certain amount of oxygen was present in the earth's atmosphere even before the biosphere arose on it. The ideas of the abiogenic origin of some part of atmospheric oxygen were also put forward by other scientists.

Both outer shells– atmosphere and hydrosphere – closely interact with each other and with other shells of the Earth, especially with the lithosphere. They are directly affected by the Sun and the Cosmos. Each of these shells is an open system, endowed with a certain autonomy and its own internal laws of development. Everyone who studies the air and water oceans is convinced. That the objects of study reveal an amazing subtlety of organization, the ability to self-regulate. But at the same time, none of earth systems does not fall out of the general ensemble, and their coexistence demonstrates not just the sum of parts, but a new quality.

Among the community of the Earth's shells special place occupies the biosphere. It captures the upper layer of the lithosphere, almost the entire hydrosphere and the lower layers of the atmosphere. The term "biosphere" was introduced into science in 1875 by the Austrian geologist E. Suess (1831 - 1914). The biosphere was understood as the totality of the living matter inhabiting the surface of the planet, together with the habitat. A new meaning to this concept was given by V.I. Vernadsky, who considered the biosphere as systemic education. The significance of this system goes beyond the purely terrestrial world, which is a link on a cosmic scale.

Age of the Earth

In 1896, the phenomenon of radioactivity was discovered, which led to the development of radiometric dating methods. Its essence is as follows. The atoms of some elements (uranium, radium, thorium and others) do not remain constant. The original, called the parent element spontaneously disintegrates, turning into a stable child. For example, uranium - 238, decaying, turns into lead - 206, and potassium - 40 - into argon - 40. By measuring the number of parent and child elements in a mineral, you can calculate the time elapsed since its formation: the greater the percentage of child elements, the older mineral.

According to radiometric dating, the oldest minerals on Earth are 3.96 billion years old, and the oldest single crystals are 4.3 billion years old. Scientists believe that the Earth itself is older, because the radiometric count is from the moment of crystallization of minerals, and the planet existed in a molten state. These data, together with the results of studies of lead isotopes in meteorites, allow us to conclude that the entire solar system was formed approximately 4.55 billion years ago.

5.5. Origin of continents. Evolution of the Earth's Crust: Plate Tectonics

In 1915, the German geophysicist A. Wegener (1880 - 1930) suggested, based on the outline of the continents, that in geological period there was a single land mass, named by him Pangea(from the Greek. "the whole earth"). Pangea split into Laurasia and Gondwana. 135 million years ago Africa separated from South America, and 85 million years ago North America separated from Europe; 40 million years ago, the Indian continent collided with Asia and Tibet and the Himalayas appeared.

The decisive argument in favor of the adoption of this concept was the empirical discovery in the 50s of the XX century of the expansion of the ocean floor, which served as the starting point for the creation of lithospheric plate tectonics. At present, it is believed that the continents move apart under the influence of deep convective currents directed upwards and to the sides and pulling the plates on which the continents float. This theory is also confirmed by biological data on the distribution of animals on our planet. The theory of continental drift, based on lithospheric plate tectonics, is now universally recognized in geology.

Also in favor of this theory is the fact that the coastline of eastern South America coincides strikingly with the coastline of western Africa, and the coastline of eastern North America- with the coastline of the western part of Europe.

One of modern theories, explaining the dynamics of processes in the earth's crust, is called theory of neomobilism. Its origin dates back to the end of the 60s of the XX century and was caused by the sensational discovery at the bottom of the ocean of a chain of mountain ranges entwining the globe. There is nothing like it on land. The Alps, the Caucasus, the Pamirs, the Himalayas, even taken together, are incomparable with the discovered strip of the mid-ocean ridges. Its length exceeds 72 thousand km.

Mankind, as it were, discovered a previously unknown planet. The presence of narrow depressions and large basins, deep gorges stretching almost continuously along the axis of the mid-range ridges, thousands of mountains, underwater earthquakes, active volcanoes, strong magnetic, gravitational and thermal anomalies, hot deep-sea springs, collosal accumulations of ferromanganese nodules - all this was discovered in a short period of time. time at the bottom of the ocean.

As it turned out, the oceanic crust is characterized by constant renewal. It originates at the bottom of a rift that crosses the median ridges along the axis. The ridges themselves are from the same font and are also young. The oceanic crust "dies" in places of splits - where it moves under neighboring plates. Sinking deep into the planet, into the mantle and melting, it manages to give part of itself, along with the sedimentary deposits accumulated on it, for the construction of the continental crust. The density stratification of the Earth's interior gives rise to a kind of flow in the mantle. These currents provide a supply of material for growth ocean floor. They also force global plates with continents protruding from the oceans to drift. The drift of large plates of the lithosphere with the land rising on them is called neomobilism.

The movement of the continents is currently confirmed by observations from spacecraft. birth oceanic crust researchers saw with their own eyes, approaching the bottom of the Atlantic, the Pacific and Indian oceans, the Red Sea. Using state-of-the-art deep-sea diving techniques, the scuba divers discovered cracks in the stretchable bottom and young volcanoes rising from such cracks.

Methods for studying the internal structure and composition of the Earth

Methods for studying the internal structure and composition of the Earth can be divided into two main groups: geological methods and geophysical methods. Geological methods are based on the results of a direct study of rock strata in outcrops, mine workings (mines, adits, etc.) and boreholes. At the same time, researchers have at their disposal the entire arsenal of methods for studying the structure and composition, which determines the high degree of detail of the results obtained. At the same time, the possibilities of these methods in studying the depths of the planet are very limited - the deepest well in the world has a depth of only -12262 m (Kola superdeep in Russia), even smaller depths have been achieved when drilling the ocean floor (about -1500 m, drilling from the side of the American research vessel "Glomar Challenger"). Thus, depths not exceeding 0.19% of the planet's radius are available for direct study.

Information about the deep structure is based on the analysis of indirect data obtained geophysical methods, mainly patterns of change with the depth of different physical parameters(electrical conductivity, mechanical figure of merit, etc.) measured during geophysical surveys. The development of models of the internal structure of the Earth is based primarily on the results of seismic studies based on data on the patterns of propagation of seismic waves. In the centers of earthquakes and powerful explosions, seismic waves arise - elastic vibrations. These waves are divided into volume waves - propagating in the bowels of the planet and "translucent" them like X-rays, and surface waves - propagating parallel to the surface and "probing" the upper layers of the planet to a depth of tens or hundreds of kilometers.
Body waves, in turn, are divided into two types - longitudinal and transverse. Longitudinal waves having great speed propagation, are first recorded by seismic receivers, they are called primary or P-waves ( from English. primary - primary), the "slower" transverse waves are called S-waves ( from English. secondary - secondary). Transverse waves are known to have important feature– they spread only in a solid medium.

At the boundaries of media with different properties, waves are refracted, and at the boundaries of sharp changes in properties, in addition to refracted, reflected and converted waves arise. Shear waves can be offset perpendicular to the plane of incidence (SH waves) or offset in the plane of incidence (SV waves). When crossing the boundary of media with different properties, the SH waves experience ordinary refraction, and the SV waves, in addition to the refracted and reflected SV waves, excite P-waves. This is how a complex system seismic waves, "translucent" the bowels of the planet.

Analyzing the patterns of wave propagation, it is possible to identify inhomogeneities in the bowels of the planet - if at a certain depth an abrupt change in the propagation velocities of seismic waves, their refraction and reflection is recorded, it can be concluded that at this depth there is a boundary of the Earth's inner shells, differing in their physical properties.

The study of the ways and speed of propagation of seismic waves in the bowels of the Earth made it possible to develop a seismic model of its internal structure.

Seismic waves, propagating from the earthquake source into the depths of the Earth, experience the most significant jumps in velocity, refract and reflect on seismic sections located at depths 33 km and 2900 km from the surface (see fig.). These sharp seismic boundaries make it possible to divide the bowels of the planet into 3 main internal geospheres - the earth's crust, mantle and core.

The earth's crust is separated from the mantle by a sharp seismic boundary, on which the velocity of both longitudinal and shear waves. Thus, the speed of transverse waves increases sharply from 6.7-7.6 km/s in the lower part of the crust to 7.9-8.2 km/s in the mantle. This boundary was discovered in 1909 by the Yugoslavian seismologist Mohorovic and was subsequently named Mohorović border(often abbreviated as the Moho or M boundary). The average depth of the boundary is 33 km (it should be noted that this is a very approximate value due to different thicknesses in different geological structures); at the same time, under the continents, the depth of the Mohorovichich section can reach 75-80 km (which is fixed under young mountain structures - the Andes, Pamir), under the oceans it decreases, reaching a minimum thickness of 3-4 km.

An even sharper seismic boundary separating the mantle and core is fixed at depth 2900 km. On this seismic section, the velocity of P-waves abruptly drops from 13.6 km/s at the base of the mantle to 8.1 km/s in the core; S-waves - from 7.3 km / s to 0. The disappearance of transverse waves indicates that the outer part of the core has the properties of a liquid. The seismic boundary separating the core and mantle was discovered in 1914 by the German seismologist Gutenberg and is often called Gutenberg border, although this name is not official.

Sharp changes in the speed and nature of the passage of waves are recorded at depths of 670 km and 5150 km. Border 670 km divides the mantle into upper mantle (33-670 km) and lower mantle (670-2900 km). Border 5150 km divides the core into an external liquid (2900-5150 km) and an internal solid (5150-6371 km).

Significant changes are also noted in the seismic section 410 km dividing the upper mantle into two layers.

The obtained data on global seismic boundaries provide a basis for considering a modern seismic model of the deep structure of the Earth.

outer shell solid earth is Earth's crust bounded by the Mohorovichic boundary. This is a relatively thin shell, the thickness of which ranges from 4-5 km under the oceans to 75-80 km under continental mountain structures. The upper crust is distinctly distinguished in the composition of the sedimentary layer, consisting of non-metamorphosed sedimentary rocks, among which volcanics may be present, and underlying it consolidated, or crystalline,bark, formed by metamorphosed and igneous intrusive rocks. There are two main types of the earth's crust - continental and oceanic, fundamentally different in structure, composition, origin and age.

continental crust lies under the continents and their underwater margins, has a thickness of 35-45 km to 55-80 km, 3 layers are distinguished in its section. The upper layer, as a rule, is composed of sedimentary rocks, including a small amount of weakly metamorphosed and igneous rocks. This layer is called sedimentary. Geophysically, it is characterized by a low P-wave velocity in the range of 2-5 km/s. The average thickness of the sedimentary layer is about 2.5 km.
Below is the upper crust (granite-gneiss or "granite" layer), composed of igneous and metamorphic rocks rich in silica (on average, corresponding in chemical composition to granodiorite). The velocity of P-waves in this layer is 5.9-6.5 km/s. At the base of the upper crust, the Konrad seismic section is distinguished, reflecting an increase in the velocity of seismic waves during the transition to the lower crust. But this section is not fixed everywhere: in the continental crust, a gradual increase in wave velocities with depth is often recorded.
The lower crust (granulite-mafic layer) is distinguished by a higher wave speed (6.7-7.5 km/s for P-waves), which is due to a change in the rock composition during the transition from the upper mantle. According to the most accepted model, its composition corresponds to granulite.

Rocks of various geological ages take part in the formation of the continental crust, up to the most ancient ones, about 4 billion years old.

oceanic crust has a relatively small thickness, an average of 6-7 km. In its most general form, two layers can be distinguished in its section. The upper layer is sedimentary, characterized by low thickness (about 0.4 km on average) and low P-wave speed (1.6-2.5 km/s). The lower layer - "basalt" - is composed of basic igneous rocks (above - basalts, below - basic and ultrabasic intrusive rocks). Speed longitudinal waves in the "basalt" layer increases from 3.4-6.2 km/s in basalts to 7-7.7 km/s in the lowest horizons of the crust.

The oldest rocks of modern oceanic crust are about 160 million years old.

Mantle It is the largest inner shell of the Earth in terms of volume and mass, bounded from above by the Moho boundary, from below by the Gutenberg boundary. In its composition, the upper mantle and lower mantle are distinguished, separated by a boundary of 670 km.

The upper mania is divided into two layers according to geophysical features. Upper layer - subcrustal mantle- extends from the Moho boundary to depths of 50-80 km under the oceans and 200-300 km under the continents and is characterized by a smooth increase in the speed of both longitudinal and transverse seismic waves, which is explained by the compaction of rocks due to the lithostatic pressure of the overlying strata. Below the subcrustal mantle to the global interface of 410 km there is a layer of low velocities. As follows from the name of the layer, the seismic wave velocities in it are lower than in the subcrustal mantle. Moreover, lenses that do not transmit S-waves at all are revealed in some areas, which gives grounds to state that the mantle substance in these areas is in a partially molten state. This layer is called the asthenosphere ( from the Greek "asthenes" - weak and "sphair" - sphere); the term was introduced in 1914 by the American geologist J. Burrell, often referred to in English literature as LVZ - Low Velocity Zone. In this way, asthenosphere- this is a layer in the upper mantle (located at a depth of about 100 km under the oceans and about 200 km or more under the continents), identified on the basis of a decrease in the speed of passage of seismic waves and having a reduced strength and viscosity. The surface of the asthenosphere is well established by a sharp decrease in resistivity (to values ​​of about 100 Ohm . m).

The presence of a plastic asthenospheric layer, which differs in mechanical properties from the solid overlying layers, gives grounds for isolating lithosphere- the solid shell of the Earth, including the earth's crust and subcrustal mantle, located above the asthenosphere. The thickness of the lithosphere is from 50 to 300 km. It should be noted that the lithosphere is not a monolithic stone shell of the planet, but is divided into separate plates constantly moving along the plastic asthenosphere. The foci of earthquakes and modern volcanism are confined to the boundaries of lithospheric plates.

Deeper than 410 km in the upper mantle, both P- and S-waves propagate everywhere, and their speed increases relatively monotonously with depth.

AT lower mantle, separated by a sharp global boundary of 670 km, the speed of P- and S-waves increases monotonically, without abrupt changes, up to 13.6 and 7.3 km/s, respectively, up to the Gutenberg section.

In the outer core, the speed of P-waves sharply decreases to 8 km/s, while S-waves completely disappear. The disappearance of transverse waves suggests that the outer core of the Earth is in a liquid state. Below the 5150 km section, there is an inner core in which the speed of P-waves increases, and S-waves begin to propagate again, which indicates its solid state.

The fundamental conclusion from the velocity model of the Earth described above is that our planet consists of a series of concentric shells representing a ferruginous core, a silicate mantle, and an aluminosilicate crust.

Geophysical characteristics of the Earth

Distribution of mass between the inner geospheres

The bulk of the Earth's mass (about 68%) falls on its relatively light, but large mantle, with about 50% falling on the lower mantle and about 18% on the upper. The remaining 32% of the total mass of the Earth falls mainly on the core, and its liquid outer part (29% of the total mass of the Earth) is much heavier than the inner solid part (about 2%). Only less than 1% of the total mass of the planet remains on the crust.

Density

The density of the shells naturally increases towards the center of the Earth (see fig.). The average density of the bark is 2.67 g/cm 3 ; at the Moho border, it increases abruptly from 2.9-3.0 to 3.1-3.5 g/cm3. In the mantle, the density gradually increases due to the compression of the silicate substance and phase transitions(restructuring of the crystalline structure of the substance in the course of "adaptation" to increasing pressure) from 3.3 g/cm 3 in the subcrustal part to 5.5 g/cm 3 in the lower mantle. At the Gutenberg boundary (2900 km), the density almost doubles abruptly, up to 10 g/cm 3 in the outer core. Another jump in density - from 11.4 to 13.8 g / cm 3 - occurs at the border of the inner and outer core (5150 km). These two sharp density jumps are of a different nature: at the mantle/core boundary, the chemical composition of matter changes (transition from the silicate mantle to the iron core), while the jump at the 5150 km boundary is associated with a change state of aggregation(transition from a liquid outer core to a solid inner one). In the center of the Earth, the density of matter reaches 14.3 g/cm 3 .

Pressure

The pressure in the Earth's interior is calculated based on its density model. The increase in pressure as you move away from the surface is due to several reasons:

compression due to the weight of the overlying shells (lithostatic pressure);

phase transitions in chemically homogeneous shells (in particular, in the mantle);

the difference in the chemical composition of the shells (crust and mantle, mantle and core).

At the foot of the continental crust, the pressure is about 1 GPa (more precisely, 0.9 * 10 9 Pa). In the Earth's mantle, the pressure gradually increases, reaching 135 GPa at the Gutenberg boundary. In the outer core, the pressure growth gradient increases, while in the inner core, on the contrary, it decreases. The calculated values ​​of pressure at the boundary between the inner and outer cores and near the center of the Earth are 340 and 360 GPa, respectively.

Temperature. Sources of thermal energy

The geological processes occurring on the surface and in the bowels of the planet are primarily due to thermal energy. Energy sources are divided into two groups: endogenous (or internal sources), associated with the generation of heat in the bowels of the planet, and exogenous (or external in relation to the planet). The intensity of the flow of thermal energy from the depths to the surface is reflected in the magnitude of the geothermal gradient. geothermal gradient is the temperature increment with depth, expressed in 0 C/km. The "inverse" characteristic is geothermal stage- depth in meters, upon immersion to which the temperature will increase by 1 0 С. areas with a calm tectonic regime. With depth, the value of the geothermal gradient decreases significantly, averaging about 10 0 С/km in the lithosphere, and less than 1 0 С/km in the mantle. The reason for this lies in the distribution of thermal energy sources and the nature of heat transfer.

Sources of endogenous energy are the following.
1. Energy of deep gravitational differentiation, i.e. heat release during the redistribution of matter in density during its chemical and phase transformations. The main factor in such transformations is pressure. The core-mantle boundary is considered as the main level of this energy release.
2. Radiogenic heat produced by the decay of radioactive isotopes. According to some calculations, this source determines about 25% heat flow emitted by the earth. However, it should be taken into account that elevated contents of the main long-lived radioactive isotopes - uranium, thorium and potassium are observed only in the upper part of the continental crust (isotopic enrichment zone). For example, the concentration of uranium in granites reaches 3.5 10 -4%, in sedimentary rocks - 3.2 10 -4%, while in the oceanic crust it is negligible: about 1.66 10 -7%. Thus, radiogenic heat is additional source heat in the upper part of the continental crust, which determines the high value of the geothermal gradient in this region of the planet.
3. Residual heat, preserved in the depths since the formation of the planet.
4. Solid tides, due to the attraction of the moon. The transition of kinetic tidal energy into heat occurs due to internal friction in rock masses. The share of this source in the total heat balance is small - about 1-2%.

In the lithosphere, the conductive (molecular) mechanism of heat transfer predominates; in the sublithospheric mantle of the Earth, a transition occurs to a predominantly convective mechanism of heat transfer.

Calculations of temperatures in the bowels of the planet give the following values: in the lithosphere at a depth of about 100 km, the temperature is about 1300 0 C, at a depth of 410 km - 1500 0 C, at a depth of 670 km - 1800 0C, at the boundary of the core and mantle - 2500 0 C, at a depth of 5150 km - 3300 0 C, in the center of the Earth - 3400 0 C. In this case, only the main (and most probable for deep zones) heat source, the energy of deep gravitational differentiation, was taken into account.

Endogenous heat determines the course of global geodynamic processes. including the movement of lithospheric plates

On the surface of the planet, the most important role is played by exogenous source heat - solar radiation. Below the surface, the effect of solar heat is sharply reduced. Already at a shallow depth (up to 20-30 m) there is a zone of constant temperatures - a region of depths where the temperature remains constant and is equal to the average annual temperature of the region. Below the belt of constant temperatures, heat is associated with endogenous sources.

Earth magnetism

The earth is a giant magnet with a magnetic force field and magnetic poles that are close to geographic, but do not coincide with them. Therefore, in the readings of the magnetic needle of the compass, magnetic declination and magnetic inclination are distinguished.

Magnetic declination is the angle between the direction of the magnetic needle of the compass and geographic meridian at this point. This angle will be the largest at the poles (up to 90 0) and the smallest at the equator (7-8 0).

Magnetic inclination- the angle formed by the inclination of the magnetic needle to the horizon. When approaching the magnetic pole, the compass needle will take a vertical position.

It is assumed that the occurrence of a magnetic field is due to systems electric currents, arising from the rotation of the Earth, due to convective motions in the liquid outer core. The total magnetic field consists of the values ​​of the main field of the Earth and the field due to ferromagnetic minerals in the rocks of the earth's crust. Magnetic properties characteristic of minerals - ferromagnets, such as magnetite (FeFe 2 O 4), hematite (Fe 2 O 3), ilmenite (FeTiO 2), pyrrhotite (Fe 1-2 S), etc., which are minerals and are established by magnetic anomalies. These minerals are characterized by the phenomenon of remanence, which inherits the orientation of the Earth's magnetic field that existed at the time of the formation of these minerals. The reconstruction of the location of the Earth's magnetic poles in different geological epochs indicates that the magnetic field periodically experienced inversion- a change in which the magnetic poles are reversed. The process of changing the magnetic sign geomagnetic field lasts from several hundred to several thousand years and begins with an intense decrease in the intensity of the main magnetic field of the Earth to almost zero, then the reverse polarity is established and after a while a rapid restoration of the intensity follows, but of the opposite sign. North Pole took the place of the southern one and vice versa, with an approximate frequency of 5 times in 1 million years. The current orientation of the magnetic field was established about 800 thousand years ago.

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MINISTRY OF EDUCATION AND SCIENCE OF THE RUSSIAN FEDERATION FEDERAL STATE AUTONOMOUS

EDUCATIONAL INSTITUTION OF HIGHER PROFESSIONAL EDUCATION

KAZAN (VOLGA) FEDERAL UNIVERSITY

Institute of Ecology and Geography

Department of Geography and Cartography

abstract

Remote Earth Exploration Methods

Completed by a 3rd year student

group No. 02-106

Yalalov D.

Scientific adviser:

Denmukhametov R.R.

Kazan - 2013

Introduction

1. Remote methods

2. Emergence of space methods

3. Aerial photography

3.1. The emergence of aerial photography

3.2. The use of aerial photography in the national economy

4. Remote sensing in the search for minerals

5. Methods for automating the interpretation of space materials

Conclusion

List of sources used

Introduction

The rapid development of astronautics, progress in the study of near-Earth and interplanetary space, revealed a very high efficiency in the use of near-Earth space and space technologies in the interests of many Earth sciences: geography, hydrology, geochemistry, geology, oceanology, geodesy, hydrology, geoscience.

The use of artificial Earth satellites for communications and television, operational and long-term weather forecasting and hydrometeorological conditions, for navigation on sea routes and air routes, for high-precision geodesy, the study of the Earth's natural resources and environmental control is becoming more common. In the near future and in the longer term, the versatile use of space and space technology in various fields economy will increase significantly

1. Remotemethods

Remote methods - common name methods for studying terrestrial objects and space bodies in a non-contact way at a considerable distance (for example, from the air or from space) with various instruments in different regions of the spectrum (Fig. 1). Remote methods make it possible to evaluate the regional features of the studied objects, which are detected at large distances. The term became widespread after the launch in 1957 of the world's first artificial satellite of the Earth and the shooting of the far side of the moon by the Soviet automatic station"Zond-3" (1959).

Rice. 1. Main geometric parameters of the scanning system: - viewing angle; X and Y - linear scanning elements; dx and dy - elements for changing the instantaneous angle of view; W - direction of movement

Distinguish active remote methods based on the use of radiation reflected by objects after irradiation by artificial sources, and passive, which study the own radiation of bodies and the solar radiation reflected by them. Depending on the location of the receivers, remote methods are divided into ground (including surface), air (atmospheric, or aero) and space. According to the type of equipment carrier, remote methods distinguish between aircraft, helicopter, balloon, rocket, satellite remote methods (in geological and geophysical research - aerial photography, airborne geophysical photography and space photography). Selection, comparison and analysis of spectral characteristics in different ranges of electromagnetic radiation make it possible to recognize objects and obtain information about their size, density, chemical composition, physical properties and condition. For searches radioactive ores and sources, the g-band is used to establish the chemical composition of rocks and soils - ultraviolet part of the spectrum; the light range is the most informative when studying soils and vegetation, infrared (IR) - gives estimates of body surface temperatures, radio waves - information about the surface topography, mineral composition, humidity and deep properties of natural formations and atmospheric layers.

According to the type of radiation receiver, remote methods are divided into visual, photographic, photoelectric, radiometric and radar. AT visual method(description, assessment and sketches) the registering element is the observer's eye. Photographic receivers (0.3-0.9 microns) have an accumulation effect, but they have different sensitivities in different regions of the spectrum (selective). Photoelectric receivers (radiation energy is converted directly into an electrical signal using photomultipliers, photocells and other photoelectronic devices) are also selective, but more sensitive and less inertial. For absolute energy measurements in all areas of the spectrum, and especially in the IR, receivers are used that convert thermal energy into other forms (most often into electrical ones), to present data in analog or digital form on magnetic and other information carriers for their analysis using a computer . Video information received by television, scanner (Fig.), panoramic cameras, thermal imaging, radar (side and all-round viewing) and other systems makes it possible to study the spatial position of objects, their prevalence, and link them directly to the map.

2. The emergence of space methods

Three stages can be distinguished in the history of space photography. The first stage should include photographing the Earth from high-altitude, and then from ballistic missiles, dating back to 1945-1960. The first photographs of the earth's surface were taken at the end of the 19th century. - the beginning of the twentieth century, that is, even before the use of aviation for these purposes. The first experiments on lifting cameras on rockets began to be carried out in 1901-1904. German engineer Alfred Maul in Dresden. The first photographs were taken from a height of 270-800 m, had a frame size of 40x40 mm. In this case, photographing was carried out during the descent of the rocket with a camera on a parachute. In 20-30 years. 20th century in a number of countries, attempts were made to use rockets to survey the earth's surface, but due to low altitudes (10-12 km), they were not effective.

Shooting the Earth from ballistic missiles played important role in the prehistory of the study of natural resources from various spacecraft. With the help of ballistic missiles, the first small-scale images of the Earth were obtained from a height of more than 90-100 km. The very first space photos The lands were made in 1946 using a Viking-2 ballistic missile from a height of about 120 km at the White Sand test site (New Mexico, USA). During 1946-1958. at this range, ballistic missiles were launched in a vertical direction and after reaching the maximum height (about 400 km) they fell to the Earth. On the fall trajectory, photographic images of the earth's surface were obtained on a scale of 1:50,000 - 1:100,000. photo equipment also began to be installed on Soviet meteorological rockets. The pictures were taken during the parachute descent of the head of the rocket. In 1957-1959. for filming in automatic mode, geophysical rockets were used. In 1959-1960. All-round photographic cameras were installed at high-altitude optical stations stabilized in flight, with the help of which photographs of the Earth were obtained from a height of 100-120 km. Photographs were taken in different directions, at different times of the year, at different hours of the day. This made it possible to trace the seasonal changes in the satellite image of the natural features of the Earth. The pictures taken from ballistic missiles were very imperfect: there were large discrepancies in the image scale, a small area, and the irregularity of rocket launches. But these works were necessary to develop the technique and methodology for surveying the earth's surface from artificial Earth satellites and manned spacecraft.

The second stage of photographing the Earth from space covers the period from 1961 to 1972 and is called experimental. On April 12, 1961, Yu. A. Gagarin, the first cosmonaut of the USSR (Russia), made the first visual observation of the Earth through the windows of the Vostok spacecraft. On August 6, 1961, cosmonaut G. S. Titov on the Vostok-2 spacecraft carried out observations and surveys of the earth's surface. The shooting was carried out through the windows in separate sessions throughout the flight. The research carried out during this period on the space manned spacecraft of the Soyuz series has a unique scientific value. Photographs of the daytime and twilight horizon of the Earth, the earth's surface, as well as observations of typhoons, cyclones, forest fires. From the board of the Soyuz-4 and Soyuz-5 spacecraft, visual observations of the earth's surface, photography and filming were carried out, including the areas of the Caspian Sea. Big experiments economic importance were carried out according to joint program research vessel "Akademik Shirshov", satellite "Meteor" and manned spacecraft "Soyuz-9". The research program in this case provided for the observation of the Earth using optical instruments, photographing geological and geographical objects in order to compile geological maps and possible areas of occurrence of minerals, observation and photography of atmospheric formations in order to compile meteorological forecasts. During the same period, radar and thermal imaging of the Earth and experimental photography were carried out in different zones of the visible solar spectrum, later called multi-zone photography.

3. aerial photography

Aerial photography is photography of the earth's surface from an airplane or helicopter. It is made vertically downward or obliquely to the horizon plane. In the first case, planned shots are obtained, in the second - perspective ones. To have an image of a large area, a series of aerial photographs are taken and then they are mounted together. Pictures are taken with overlap so that the same area falls into adjacent frames. Two frames make up a stereo pair. When we view them through a stereoscope, the image looks three-dimensional. Aerial photography is carried out using light filters. This allows you to see the features of nature that you will not notice with the naked eye. If shooting in infrared rays, then you can see not only the earth's surface, but also some features of the geological structure, the conditions for the occurrence of groundwater.

Aerial photography is widely used to study landscapes. With its help, accurate topographic maps are compiled without carrying out numerous difficult surveys of the terrain on the Earth's surface. It helps archaeologists find traces of ancient civilizations. The discovery in Italy of the buried Etruscan city of Spina was carried out with the help of aerial photography. This city was mentioned by geographers of past years, but it was not possible to find it until drainage work began to be carried out in the swampy delta of the Po River. Ameliorators used aerial photographs. Some of them have attracted the attention of scientists-specialists. These photographs show the flat surface of the lowland. So, in the pictures of this area, the contours of some regular geometric shapes. When the excavations began, it became clear that the once rich port city of Spina flourished here. Aerial photographs made it possible to see the location of his houses, canals, and streets by means of inconspicuous changes in vegetation and swampiness from the ground.

Aerial photographs are of great help to geologists, helping to trace the course of rocks, examine geological structures, and detect outcrops of bedrock to the surface.

In our time, in the same areas, aerial photography is carried out many times over many years. If you compare the obtained images, you can determine the nature and extent of changes in the natural environment. Aerial photography helps to record the degree of human impact on nature. Repeated images show areas of unsustainable nature management, and on the basis of these images, conservation activities are planned.

3.1 emergenceaerial photography

The emergence of aerial photography dates back to the end of the 19th century. The first photographs of the earth's surface were taken from balloons. Although they differed in many shortcomings, the complexity of obtaining and subsequent processing, the image on them was quite clear, which made it possible to distinguish many details, as well as to get an overall picture of the region under study. Further development and improvement of photography, cameras and aeronautics led to the fact that filming devices began to be installed on flying vehicles called airplanes. During the First World War, photography from airplanes was carried out with the aim of aerial reconnaissance. The location of the enemy troops, their fortifications, and the amount of equipment were photographed. This data was used to develop operational plans for combat operations.

After the end of the First World War, already in post-revolutionary Russia, aerial photography began to be used for the needs of the national economy.

3.2 Usageaerial photographyinfolkau pair

In 1924, an aerial survey site was established near the city of Mozhaisk, where newly created aerial cameras, aerial photography materials (photographic film, special paper, equipment for developing and printing images) were tested. This equipment was installed on the then existing aircraft such as Yak, Il, the new aircraft An. These studies gave positive results, which made it possible to switch to the widespread use of aerial photography in national economy. Aerial photography was carried out using a special camera, which was installed in the bottom of the aircraft with devices that eliminate vibration. The camera cassette had a film length from 35 to 60 m and a width of 18 or 30 cm, a single picture had dimensions of 18x18 cm, less often - 30x30 cm. 20th century the image in the pictures was black and white, later they began to receive color, and then spectral images.

Spectral images are made using a light filter in a certain part of the visible solar spectrum. For example, it is possible to photograph in the red, blue, green, yellow parts of the spectrum. This uses a two-layer emulsion covering the film. This way of photographing conveys the landscape in the required colors. So, for example, a mixed forest during spectral photography gives an image that can be easily divided into species that have different colors in the image. After the development and drying of the film, contact prints are prepared on photographic paper measuring 18x18 cm or 30x30 cm, respectively. Each picture has a number, a round level, which can be used to judge the degree of horizontality of the picture, as well as a clock that fixes the time at the time of taking this picture.

Photographing any area is carried out in flight, in which the aircraft flies from west to east, then from east to west. The aerial camera operates in automatic mode and takes pictures that are located along the aircraft route one after another, overlapping each other by 60%. The overlap of images between strips is 30%. In the 70s. 20th century On the basis of the An aircraft, a special An-30 aircraft was designed for this purpose. It is equipped with five cameras, which are controlled by a calculating machine, and at present - by a computer. In addition, the aircraft is equipped with an anti-vibration device that prevents lateral drift due to wind. It can withstand a given flight altitude. The first experiments in the use of aerial photography in the national economy date back to the end of the 1920s. 20th century The images were used in hard-to-reach places in the Mologa river basin. With their help, the study, survey and determination of the quality and productivity (taxation) of the forests of this territory were carried out. In addition, a little later, the Volga fairway was studied. This river often changed its fairway in some sections, shallows, spits, and embankments arose, which greatly interfered with navigation before the creation of reservoirs.

Aerial photographic materials made it possible to reveal regularities in the formation and deposition of river sediments. During the Second World War, aerial photography was also widely used in the national economy for exploration of minerals, as well as at the front to identify the movement of enemy manpower and equipment, to survey fortifications, and possible theaters of military operations. In the post-war period, aerial photography was also used in many ways.

4. Remoteresearchatsearchingusefulnyhfossil

Thus, to ensure the exploration of hydrocarbon deposits, design, construction and operation of oil and gas production, processing and transportation facilities using aerospace information, a study of the relief, vegetation, soils and soils, their condition at different times of the year, including extreme natural conditions, for example, during floods, droughts or severe frosts, analysis of the availability and condition of residential and transport infrastructure, changes in landscape components as a result of economic development territories, including as a result of accidents at oil and gas fields and pipelines, etc.

If necessary, digitization, photogrammetric and photometric processing of images, their geometric correction, scaling, quantization, contrasting and filtering, synthesizing color images, including using various filters, etc. are used.

The selection of aerospace materials and interpretation of images are made taking into account the time of day and the season of the survey, the influence of meteorological and other factors on the image parameters, the masking effect of clouds, and aerosol pollution.

In order to expand the possibilities of analyzing aerospace information, not only direct deciphering features are used, a priori known or identified in the process of a targeted study of aerospace images, but also indirect features that are widely used in visual deciphering. They are primarily based on the indication properties of the relief, vegetation, surface waters, soils and soils.

Different results are observed when shooting the same objects in different zones of the spectrum. For example, surveys in the infrared and radiothermal ranges better fix the temperature and humidity of the earth's surface, the presence of an oil film on the water surface, but the accuracy of the results of such surveys can be crossed out. strong influence physical heterogeneity of the land surface or waves on the water surface.

5. Techniquesautomationdecipheringspacematerials

The specificity of the use of satellite imagery materials is associated with a targeted approach to the interpretation of remote data, which contain information about many territorially related parameters (geographical, agricultural, geological, technogenic, etc.) of the natural environment. Computer visual interpretation is based on measurements of four-dimensional (two spatial coordinates, brightness and time) and five-dimensional (additionally, a color image in multi-zone shooting) distributions of radiation fluxes reflected by elements and objects of the terrain. Thematic image processing includes logical and arithmetic operations, classification, filtering and/or lineament analysis and a series of other methodological techniques. This should also include visual interpretation of the image on the computer screen, which is carried out using the stereo effect, as well as the entire arsenal of computer processing and image conversion tools. Ample opportunities for the researcher are opened by automatic classifications of multi-zone images (with preliminary training on standards or with specified parameters). Classifications are based on what different natural objects have in different ranges electromagnetic spectrum different brightnesses. An analysis of the brightness of objects in different zones (ROX - spectral optical characteristics) allows you to identify and outline representative landscape types, structural-material (industrial and social) complexes, and specific geological and technogenic bodies. Upgrade technology satellite images digital topographic maps based on visual interpretation should provide the following set of functions:

1) export / import of digital cartographic information and digital images of the terrain;

2) interpretation of space photographs in compliance with the optimal conditions for their processing:

Preparation of source materials for identification of terrain elements on enlarged positives (on film);

Evaluation of image resolution before and after primary processing;

Determination of direct and indirect deciphering features, as well as the use of photographic images of typical terrain elements and reference materials;

4) digitization of space images and interpretation results;

5) transformation (ortho-transformation) of digital space images;

6) preparation of statistical and other characteristics of information features of terrain elements;

7) editing the elements of the content of a digital map based on the results of image interpretation;

8) generation of an updated digital topographic map;

9) designing a digital topographic or thematic map for the user together with an image - creating a composite digital phototopographic map.

With automatic and interactive decoding, it is additionally possible to simulate signal fields at the input of the receiving equipment of aerospace monitoring systems environment; image filtering and pattern recognition operations.

But the joint observation on the screen of a layer, which can be obtained by various methods, of a vector digital map and a raster image creates new, previously unused, opportunities for automated interpretation and updating of maps.

The contour coordinates of an areal or linear terrain element on a digital map can serve as a "pesmaker" - a pointer for taking data from pixels of a raster image of the terrain with subsequent calculation of the average characteristics of the surrounding area, given dimensions, and contouring the area or drawing the corresponding curve in a new layer. If the raster parameters do not match in the next pixel of the image, it is possible to switch to the next corresponding to the same element on the map and with subsequent interactive elimination of gaps. An algorithm for continuous obtaining of statistical characteristics of averaged neighborhoods of pixels (points of segments between extrema or on splines) is possible, taking into account the allowable change in the characteristics of the rasterton, and not the entire array of equally spaced test areas along the curve.

The use of map data on the terrain makes it possible to significantly enhance the automation of decoding algorithms, especially for hydrological and geological information arrays based on direct features, using the same matching method, based on geological and gravitational relationships.

Conclusion

The use of aerospace technologies in remote sensing is one of the most promising ways to develop this area. Of course, like any research methods, aerospace sounding has its advantages and disadvantages.

One of the main disadvantages of this method is its relative high cost and, to date, insufficient clarity of the data obtained.

The above disadvantages are removable and insignificant against the background of the opportunities that open up thanks to aerospace technologies. This is an opportunity to observe vast territories for a long time, obtaining a dynamic picture, considering the influence of various factors on the territory and their relationship with each other. This opens up the possibility of a systematic study of the Earth and its individual regions.

aerial photography terrestrial remote space

Listusedsources

1. S.V. Garbuk, V.E. Gershenzon "Space systems for remote sensing of the Earth", "Scan-Ex", Moscow 1997, 296 pages.

2. Vinogradov B. V. Space methods for studying the natural environment. M., 1976.

3. Methods for automating the decoding of space materials - http://hronoinfotropos.narod.ru/articles/dzeprognos.htm

4. Remote methods for studying the earth's surface - http://ib.komisc.ru

5. Aerospace methods. Photography - http://referatplus.ru/geografi

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