CN103048691B - A kind of little loop line TEM mountainous region lay out and measuring point method for homing - Google Patents

Abstract

The invention discloses a small loop TEM mountain laying and measuring point homing method, which avoids the corner of the terrain and directly lays the loop on the hillside in a square; The calculation method of the position (xˊ,zˊ) is zˊ=z-(hˊ+h″)=z-(hcosθ+hsinθtanθ)xˊ=x+hsinθ where x is the coordinate of the measuring point relative to the starting point of the survey line, and y is the measuring point h is the detection depth of the TEM at a certain moment, and θ is the angle between the hillside and the coordinate x-axis. This method can obtain good detection accuracy without solidifying the wire frame, is easy to carry, and gives full play to the small loop TEM Advantages of mountain detection.This method can be applied to the field of geophysical prospecting, especially the field of electrical and electromagnetic prospecting.

Description

A Method for Laying Small Loop Line TEM in Mountains and Positioning Measuring Points

technical field

The invention belongs to the field of geophysical prospecting, and in particular relates to an electric and electromagnetic prospecting method.

Background technique

The small loop TEM (Transient Electro-Magnetic, TEM) technology has the advantages of lightness, flexibility, high construction efficiency, and little influence by terrain in mountain detection ^[1] . However, the transmitting and receiving loops of the small loop TEM are mostly composed of flexible wires, and the loops are not easy to be arranged horizontally on the undulating surface, resulting in a decrease in detection accuracy; if the wire frame is solidified ^[2] , it is not easy to carry, Supports or human bodies used for horizontal arrangement will also affect the measurement results, which also lead to a decrease in detection accuracy. For this reason, a method for laying loops and homing measuring points that is convenient for mountain construction is designed.

comparison file

[1] YanS, ChenMS, ShiXX.Transientelectromagneticsoundingusinga5msquareloop.ExplorationGeophysics, 2009,40(2):193-196

[2] http://www.chinafeny.com/product‐349.htm

The flexible loop of small loop TEM is not easy to arrange horizontally in mountainous exploration, resulting in a decrease in detection accuracy; if the wire frame is solidified, it is not easy to carry, and the support or human body used for horizontal arrangement will also affect the measurement results , which also leads to the decline of detection accuracy, so that the small loop TEM detection technology cannot fully utilize the advantages of mountain detection.

Contents of the invention

The purpose of the present invention is to provide a small loop TEM mountain laying and measuring point homing method to improve the detection accuracy without curing the wire frame, so that the construction of the small loop TEM mountain detection is more convenient.

In order to solve the above technical problems, the technical solution adopted by the present invention is as follows.

A small loop TEM mountain laying and measuring point homing method is characterized in that: the laying method is to avoid the corner of the terrain, and the loop is directly laid on the hillside with a square; the described measuring point homing method is In Cartesian coordinates, the calculation method of the homing point (x', z') of the measuring point (x, z) is as follows

z'=z-(h'+h")=z-(hcosθ+hsinθtanθ)

x'=x+hsinθ

The x is the coordinates of the measuring point relative to the starting point of the surveying line, z is the elevation of the measuring point, h is the detection depth of the TEM at a certain moment, and θ is the angle between the hillside and the coordinate x-axis (Fig. 2, Fig. 3).

The present invention has beneficial effects Through the loop laying method and the calculation method of measuring points and homing points of the present invention, mountain detection can be well realized, the construction of small loop TEM mountain detection is more convenient, and the small loop TEM is fully utilized. Advantages of loop TEM in mountain exploration.

Description of drawings

Figure 1 is a top view schematic diagram of the TEM laying of small loop lines in mountainous areas.

Figure 2 is a schematic diagram of the laying and homing section of the measuring points.

Figure 3 is a schematic diagram of the details of the homing of the measuring points.

The codes in the picture are: 1. Terrain, 2. Circuit, 3. Measuring point, 4. A certain point underground, 5. Homing measuring point.

detailed description

The solution of the present invention will be described in further detail below in conjunction with the accompanying drawings.

In the TEM exploration of a small loop in a mountainous area, the measuring points are laid on a relatively gentle hillside, and the slope of the hillside is obtained by the general method of geodetic survey (Fig. 2). The coordinates of one of the measuring points (Fig. 3) are (x, z)=(200m, 1260m), the detection depth h=120m of t=5ms, and the intersection angle θ=30° between the hillside where the measuring point is located and the coordinate axis. From the formula (1) we can know

x'=x+hsinθ=200+120sin30°=260m(2)

Claims (1)

1. a small loop TEM mountain laying and measuring point homing method, is characterized in that: described laying method is to avoid the corner of terrain, loop line is directly laid on hillside with square; Described measuring point homing The method is that in Cartesian coordinates, the calculation method of the homing point (x', z') of the measuring point (x, z) is as follows z'=z-(h'+h")=z-(hcosθ+hsinθtanθ) x'=x+hsinθ The x is the coordinates of the measuring point relative to the starting point of the survey line, z is the elevation of the measuring point, h is the detection depth of the TEM at a certain moment, and θ is the angle between the hillside and the coordinate x-axis.