The action that causes the constant change and formation of crustal composition, crustal structure and surface morphology is generally called geological action.
Second, the classification of geological processes.
The natural force of geological process is geological force. Force is the expression of energy. According to different energy sources, geological processes can be divided into external forces and internal forces.
1, external forces can be divided into weathering in different ways, including physical, chemical and biological effects. Denudation includes mechanical weathering, chemical weathering and handling, including mechanical handling and chemical handling. Deposition includes mechanical, chemical and biological transportation.
2. Internal force,
They occur both on the surface and inside the earth. Some are strong and urgent, such as earthquakes; Some are weak and slow, such as weathering. The present situation of the earth's surface is the result of long-term transformation of the earth's surface by geological processes.
Section 1 Research Objects and Contents of Earth Science
Human beings live on the earth, and all activities such as food, clothing, housing and transportation are inseparable from the earth. If people want to rely on mountains and rivers to obtain the means of subsistence, to exploit mineral resources from the earth to make production and living tools, to understand the natural geography and climate conditions on the earth to develop production, and to fight against various natural disasters on the earth. Therefore, in the long-term practice, human beings have gradually deepened their understanding of the earth and gradually formed a science taking the earth as the research object-earth science.
(Earth science). Earth science, referred to as geoscience, is mathematics, physics, chemistry, astronomy, earth science and biology.
One of the basic natural sciences. Earth science takes the earth as the research object, including the gas around the earth (atmosphere), the water on the surface of the earth (hydrosphere), the surface morphology of the earth and the solid earth itself. As for the biology (biosphere) on the earth's surface, it has become a special basic natural science-biology because of its extensive research content, numerous branches and special research methods. However, the origin and evolution of organisms and the relationship between organisms and the earth's living environment also belong to the research category of earth science.
Earth science is a science with strong theory and application. It is not only devoted to revealing nature.
The scientific mission of the mysteries and laws of the world also provides a scientific methodology for human beings living on the earth to use, adapt and transform nature. With the development of production and science and technology, the research contents and fields of earth science have been deepened and expanded, and a comprehensive discipline system composed of many disciplines has gradually formed. At present, earth science mainly includes geology, geophysics, geography, meteorology, hydrology, oceanography, pedology, environmental earth science and other disciplines. Among them, geology has become the main part of earth science because of its wide range of research fields and many branches. Its purpose is to study the essential characteristics of the earth, so that people sometimes use geology and earth science as synonyms. In fact, their meanings are different, and there is an inclusive relationship. With the development of science, earth science will give birth to new disciplines and some marginal disciplines.
Geography mainly studies the topography, geographical environment and structure of the earth's surface.
Distribution and evolution, and involves the relationship between nature and society. Geography can generally be divided into two parts: physical geography and human geography. Physical geography is a subject that studies the structure, occurrence and development of natural topography and geographical environment, including general physical geography, regional physical geography and geography. Human geography is a subject that studies the relationship between man and topography and geography in society and nature, including political geography, social geography, population and settlement geography, economic geography and historical geography.
Meteorology takes the atmosphere around the earth as the research object, and mainly studies various physical properties, physical phenomena and their changing laws of the atmosphere. Its research content is also very extensive, including many branches and applied disciplines. The main branches are atmospheric physics, meteorology, climatology, high-altitude meteorology, dynamic meteorology and so on. The main applied disciplines are satellite meteorology, radio meteorology, aviation meteorology, marine meteorology, agricultural meteorology, forestry meteorology and so on. Its purpose is to reveal the occurrence and development essence of various physical phenomena and processes in the atmosphere, so as to master and apply them and serve human life and national economic construction.
Hydrology and oceanography study the water bodies distributed on the earth's surface. Hydrology mainly studies the quantity, quality, movement and distribution of rivers, lakes, glaciers, groundwater and oceans on the earth, and their relationship with geographical environment and ecology.
Interaction and connection between system and human society. Oceanography studies the ocean as an independent body, which is actually independent from other branches of earth science, because the ocean plays an increasingly important role in modern earth science, human living environment and future social development. Oceanography is the general name of various disciplines that study various phenomena and laws occurring in the ocean and their relationships. According to different research contents, it can be divided into marine physics, marine water literature, marine chemistry, marine biology, marine meteorology and marine geology.
Soil science takes the soil layer developed on the earth's surface as the research object. This paper mainly studies the material composition, structure, type, distribution and formation and development process of soil. According to the different research contents and application fields, pedology also has some branches, such as soil biology, soil geography, soil climatology, soil physics, soil chemistry, soil geology and so on.
Geophysics is a discipline that studies the earth by using physical methods, and it is an important frontier discipline that combines earth science and physics developed in modern times. The research objects of generalized geophysics include solid earth, its surface water body and surrounding atmosphere. However, because the study of water and atmosphere has established corresponding independent disciplines, the so-called geophysics in the general sense is narrow, and its main research object is the solid earth, so it can also be called solid geophysics. Geophysics mainly studies various physical properties, physical phenomena and their occurrence and development, the internal structure and composition of the earth, the origin and evolution of the earth, etc. Its main branches are seismology, geomagnetism, gravity, geothermal, geoelectricity, geodesy, geotectonic physics and applied geophysics. Among them, applied geophysics mainly studies geophysical exploration methods and their applications in exploration and development of earth resources, monitoring and protection of earth environment.
The main object of geological research is also the solid earth. At present, I mainly study solids.
The surface layer of the earth-the crust or lithosphere. The thickness of the earth's crust or lithosphere is generally about tens to 200 kilometers, which is only a very thin watch case compared with the radius of the earth (637 1 km). On the one hand, this thin shell has become the main object of geological research, because it is directly related to human life, production and survival; On the other hand, it is limited by the current human ability. People can directly observe and study the earth's surface, but at this stage, people have no ability to directly study the deep underground. At present, drilling sampling is the only way for people to obtain deeper substances in the earth for direct research, but due to the limitation of current technical level, the depth that drilling can reach is limited. At present, the deepest drilling in the world (12.5km) is located in kola peninsula, northwest of Russia, which is less than half of the continental crust thickness in this area. It is believed that with the development of science and technology, the object of geological research will continue to expand to the deep part of the earth (such as mantle and core).
The research content of geology mainly includes the material group of solid earth (especially the crust or lithosphere)
Formation history, internal structure and formation and evolution. According to the different research contents and tasks, the main branches of geology can be briefly listed as follows:
(1) A discipline that studies the composition of the earth's materials, such as crystallography, mineralogy, petrology, etc.
(2) disciplines that study the internal structure of the earth, such as structural geology, structural physics, regional tectonics, geodynamics, etc. ;
(3) Study on the formation and evolution of the earth, including paleontology, stratigraphy, geo-history, paleogeography, geomorphology and Quaternary geology;
(4) The discipline of studying geological application can be divided into two aspects: one is the branch of studying underground resources, such as deposit science, petroleum geology, coalfield geology, hydrogeology, etc. The second is the study of geology, human living environment and disaster protection, such as engineering geology, environmental geology, earthquake geology and so on.
In addition, in order to better study all aspects of the above geology, people continue to absorb and learn from it.
Advanced theories, methods and technologies of other disciplines are used to promote and deepen the study of geology, so a series of marginal disciplines have gradually formed, such as mathematical geology, geochemistry, isotope geology, astronomical geology, marine geology, remote sensing geology, experimental geology, etc., which play an extremely important role in the study of modern geology.
In recent decades, due to the rapid development of industry, agriculture, military, aerospace, transportation and other industries around the world, the results have brought great influence to the natural environment of the earth. Some of these impacts are direct (such as pollution) and some are indirect (such as climate change). It has seriously affected the natural ecology of the earth and the survival and development of human beings, so it has been widely concerned by scientists and all mankind. This problem is closely related to earth science and environmental science, so a marginal subject-environmental earth science has gradually formed in earth science. Environmental geoscience mainly studies the composition, structure, formation and evolution of the earth's natural environment, as well as the destruction, pollution, prevention, protection, improvement and evaluation of the environment. According to the different research emphases of earth sciences, it can be divided into environmental geology, environmental geography, environmental meteorology, environmental hydrology, environmental oceanography, environmental pedology and so on.