I want to know more about geophysical prospecting?

Geophysical prospecting is to do CT for the earth, and in layman's terms, it is explorationThe internal structure of the Earthand tectonics, studying petrophysical properties, observing the distribution and changes of various physical fields, searching for energy and resources.

Engineering geophysical prospecting generally refers to a geophysical exploration method used to solve engineering geology and hydrogeological problems in engineering survey, and the physical basis of its application is underground geophysical field (gravity field, electromagnetic field).

elastic wave fields, etc.) are affected by underground geological bodies.

Areas of application include:1. Regional geological survey, such as fault structure, bedrock weathering, and building bearing layer in the region.

distribution and so on. 2. Engineering geological environment survey, provide information for engineering design, and survey the geological disasters that may occur around the project.

3. Advanced geological forecasting, such as the detection of the sand layer of soft soil orange cover during the construction of subway and other projects.

4. Monitoring of project construction quality and construction status, such as pile foundation detection.

Concrete quality inspection, urban underground pipeline detection, reservoir dam leakage, etc.

5. Archaeological investigation.

Geophysical prospecting belongsGeological exploration, a means of resource exploration. In the future, you can work in the geology industry or the energy industry. For example, the Petroleum Geophysical Prospecting Bureau, coalfieldsDepartment of Geology, Bureau of Geology and Mineral Exploration and Development.

There are also some engineering geophysical prospecting companies, foundationsconstruction unitA foundation survey is required. The work is generally hard. But the treatment is okay.

Geophysical exploration.

Referred to as geophysical prospecting, it refers to the detection of geological conditions such as stratum lithology and geological structure by studying and observing the changes of various geophysical fields. Because the different rock formations that make up the earth's crust are often characterized by density, elasticity, electrical conductivity, magnetism, and radioactivity.

and thermal conductivity, etc., which will cause local variations in the corresponding geophysical fields.

By measuring the distribution and variation characteristics of these physical fields, and analyzing and studying them in combination with known geological data, the purpose of inferring geological properties can be achieved. This method has both exploration and test functions, and compared with drilling, it has the advantages of light equipment, low cost, high efficiency and wide working space. However, because it cannot be sampled and cannot be directly observed, it is mostly used in conjunction with drilling.

Geophysical exploration is based on the difference in physical properties, density, magnetization, conductivity, and radioactivity between rocks, ores (or strata) and surrounding rocks. Geoscience terminology, geophysics.

Using the principles and methods of physics, the distribution and changes of various physical fields of the earth are observed.

Geophysical exploration explores the medium structure, material composition, formation and evolution of the earth's differential match ontology and near-Earth space, and studies various natural phenomena related to them and their change laws.

On this basis, it is necessary to detect the internal structure of the earth.

It provides theories, methods and technologies for structuring, searching for energy, resources and environmental monitoring, and provides an important basis for disaster forecasting. The late famous geophysicist.

Mr. Zhao Jiuzhang described geophysics as follows: "The upper and the poorer and the lower yellow springs, and the two places are nowhere to be seen." The research content of geophysics can be divided into two categories: applied and theoretical geophysics, which belong to the first-level discipline of geophysics.

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Petrophysical properties commonly used in geophysical exploration are: density and magnetic permeability.

Electrical conductivity, elasticity, thermal conductivity.

Radioactivity. The corresponding exploration methods are: gravity exploration, magnetic exploration, electric exploration, ** exploration, geothermal exploration, and nuclear exploration.

From the difference of the spatial location and area where the measurement is located, it can be divided into: ground geophysical exploration, airborne geophysical exploration, marine geophysical exploration, borehole geophysical virtual exploration, etc.

According to the different research objects, it can also be divided into: metal geophysical exploration, petroleum geophysical exploration, coal field geophysical exploration, hydrogeological geophysical exploration, engineering geological geophysical exploration and deep geological geophysical exploration.

The geophysical prospecting method is an indirect observation method, which uses physical principles and instruments to obtain the physical parameters and laws of known rock and ore specimens or models, and then interprets the parameter values of actual field observations according to the established physical properties (mathematical and physical models), and then interprets the geophysical prospecting results (physical profiles, sections, plans, etc.) into geological results.

Common engineering geophysical prospecting methods and characteristics.

Electrical exploration: including electric bathymetry, electric profile, high-density electric method, natural electric field method, charging method, excited polarization method, controllable source audio magnetotelluric sounding method, transient electromagnetic method, etc.;

Ground penetrating radar: profile method, wide-angle method, ring method, transmission method, single hole method, multi-profile method, etc.

**Exploration: including shallow refracted wave method, shallow reflected wave method and Rayleigh wave method;

Elastic wave testing: including acoustic wave method and **wave method. The acoustic wave method can choose single-hole sound wave, penetrating sound wave, surface sound wave, sound wave reflection, pulse echo, etc.; The wave method can be used for logging, penetration, wave velocity test, continuous wave velocity test, etc.;

Tomography: including acoustic tomography, **wave tomography, electromagnetic wave absorption coefficient tomography or electromagnetic wave velocity tomography, etc.

By studying and observing the changes of various geophysical fields, we can detect geological conditions such as stratum lithology and geological structure. It is based on the difference in physical properties, density, magnetization, conductivity, and radioactivity between rocks, ores (or strata) and surrounding rocks. Geophysics: The principles and methods of physics are used to observe the distribution and changes of various physical fields of the earth.

Development direction: the introduction of modern electronic computer technology, to further suppress interference, improve resolution, extract more useful information, the development of inversion theory and technology, improve the geophysical interpretation and inference effect of various geological problems, and continuously improve the efficiency of geophysical data processing and image processing technology.

Geophysical exploration instruments should be developed in the direction of lightweight, high-precision, multi-functional, digital, serialized and intelligent. The development of modern geological theories has made the study of deep geological problems more and more important. Geophysical exploration methods such as artificial reflection profile, magnetotelluric bathymetry, gravity, magnetic method, and geothermal have shown their potential and superiority in this research.

The geophysical prospecting method is an indirect observation method, which uses physical principles and instruments to obtain the physical parameters and laws of known rock and ore specimens or models, and then interprets the parameters of the actual field observation according to the established physical properties of the coarse socks (mathematical and physical model), and then interprets the geophysical prospecting results (physical property profile, section, plan, etc.) into geological results.

Extension: The so-called forward modeling is to study the relationship between lithology-physical properties-curve (the relationship curve between physical property parameters and time or space), and assume the physical model to obtain the mathematical model; Inversion is to study the relationship between curves and physical lithology, and interpret the curve according to the mathematical physical model to obtain lithology.

The same lithology has a variety of physical properties, which can be described by multiple physical parameters, and a number of curves with different parameters can be obtained by using different observation methods. Of course, different lithologies may also have the same or similar physical properties, which is why geophysical methods are multi-solving.