Figure 4-5- 13 envi mag proton precession magnetometer appearance
(a) the structure principle and application scope of the instrument
ENVI system enables you to flexibly find anomalies that are more and more difficult to find. An ENVI system is economical and portable, and it is a portable proton precession magnetometer/gradiometer with VLF function (Figure 4-5- 13), which can ensure you to measure quickly and accurately in a large area, and monitor the data quality in real time in the form of icons to avoid invalid work; It allows you to look for anomalies that are becoming more and more difficult to find. Applicable to: ① environmental site characteristics; ② Groundwater exploration; ③ Mineral exploration; ④ Archaeology; ⑤ Geological mapping; ⑥ Groundwater research; ⑦ Geotechnical engineering research; ⑧ Civil engineering.
(2) Main technical indicators
Practical guidance of applied geophysics teaching
"Walking" Mode at 2s Sampling Rate
0.5s cycle speed
This keyboard * * * has 17 keys, among which the most commonly used keys are arranged on the left and right sides of the dashboard (Figure 4-5- 14), namely the start/stop key and the recording key. Some keys also have triple functions, and various functions are embodied in different working processes.
Fig. 4-5- 14 ENVIMAG proton precession magnetometer console panel
On/off turns the instrument on and off.
Stop/stop/clear to start or stop the operation.
* data acquisition data playback;
* Check the data;
* When the instrument is in the state of text information display, the input can be deleted.
Setup/5/MnO (Setup) enters various status setting displays, and the displayed setting menu depends on the current display content. As long as you press this key, the setting status will appear.
Aux/ 1/arc (auxiliary) enters the auxiliary function key to complete the following functions.
* set the brightness of the LCD screen;
* data output;
* lock setting parameters;
* Rewrite the main system software.
←/2/def →/3/ghi Move the cursor up and down, left and right.
There are two similar keys on the ENTER/RATE keyboard, located at the left and right corners of the panel.
* In the setting state, open and close the selection range of various parameters;
* graphic display, open and close the selection range of drawing scale factor;
* In the continuous walking measurement mode, select the sitting speed marker.
(3) ENVI magnetic measurement system operation keyboard
Escape/0 (Return) can return to the previous menu from the current menu. The top menu is always displayed in the main operation menu.
* Press this button to interrupt data output.
Info/7/Stu (information) Press this button to enter the information display, which has different functions in the state of magnetic field measurement:
* in the basic state and search state can enter the help menu display;
* advanced state, which has the following functions;
* Set the year, month, day, hour, minute and second;
* input instrument number and work number and operator identification number;
* Check the amount of memory.
There are two similar keys on the next keyboard, located on the left and right sides of the panel, with the following functions:
* according to the page order scroll display all digital data;
* according to the page order scroll display all graphics data;
* Move the cursor from the current page to the next page;
* during the text display, move the cursor along the characters in turn;
* During continuous measurement walking, select points through point increment.
Note /6/FQR enters the text display with the following functions:
* using the selected readings, you can enter five common repeated record information;
* Use special readings to enter unique recorded information.
Num/GRA/4/JKL digital graphics.
* Only used to mark digital and graphic data display during data acquisition.
Memories /9/YZ (playback)
* playback browsing data display options;
* display the type of browsing data to be played back;
* Set the starting position "point" and time of browsing data to be played back.
Record (record) records the measurement data manually, and prompts the memory capacity.
Tie-pt/8/vwx (connection point correction) When measuring connection points, this key is similar to the start key, that is, the measurement key. This key is only used to measure when the connection point is encountered in the survey line observation process, and also used to correct the daily variation of the cycle state by using the data of the connection point.
+-has the function of scrolling the menu table forward or backward repeatedly;
* Symbolic figures;
* During visiting and browsing the survey data, the data can be displayed as a survey line;
* display graphics, you can choose the proportion;
* In point-by-point measurement, the number of dotted lines can be increased or decreased.
1-9, A-Z can input letters and numbers for text input and function setting.
The blank key in the upper left corner of the buzzer/port dashboard is a key with no practical function at present, but the flexible film on the surface of the key further improves the volume of the buzzer.
On/Off+AUX/LCD/ 1/ABC press these two keys at the same time for cold start operation, so that the instrument can restore the factory parameter settings.
Press on/off+setting /5/MnO at the same time to complete the following functions:
* Choose one of three methods: total magnetic field measurement (MAG), very low frequency measurement (VLF) and simultaneous measurement of total magnetic field and very low frequency (MAG&VLF);
* In MAG mode, select one of three measurement states, such as basic state, search state or advanced state.
(4) Operation process
(1) Before each different measurement, press "Setup" and "On" to initialize the instrument and enter the function menu (Figure 4-5- 15): press "1", "2" or "3" to select the measurement state to enter.
The 4-5- 15 ENVI measurement main menu
(2) Press the "1" key to enter the magnetometer working status menu, which occupies two display screens. Press "+"and "-"to switch, as shown in Figure 4-5- 16.
Figure 4-5- 16 ENVI application menu status of the total field
(3) Basic state. When the key "1", "2" or "3" is pressed, the basic measurement state will be entered, as shown in Figure 4-5- 17.
The 4-5- 17 ENVI basic measurement status menu
At any time, press "Digital /GRA" to display the profile of the last 178 point of the current survey line, press "Next" to display the precession attenuation signal of the last data, and then press "Digital /GRA" to return to data display.
(4) Search status. When "4" is selected from (2), the display is as shown in Figure 4-5- 18.
The 4-5- 18 ENVI search status menu
After the setting is completed, press the "Start" key to start the measurement.
At any time, press "Digital /GRA" to display the profile of the last 178 point of the current survey line, press "Next" to display the precession attenuation signal of the last data, and then press "Digital /GRA" to return to data display.
(5) advanced status. Select "5", "6" or "7" from (2) to enter the advanced state, as shown in Figure 4-5- 19.
The 4-5- 19 ENVI advanced status menu
Press the "Setup" key to enter the instrument function setting display, as shown in Figure 4-5-20.
Figure 4-5-20 ENVI Advanced Instrument Settings Menu
After the setting is completed, press the "Start" key to start the measurement. Press the "Setup" key to enter the magnetometer setup display, as shown in Figure 4-5-2 1.
Figure 4-5-2 1 ENVI advanced state magnetometer setting menu
After setting, press ESC key to return to (5), and press "Start" key to start measurement.
At any time, press "Digital /GRA" to display the profile of the last 178 point of the current survey line, press "Next" to display the precession attenuation signal of the last data, and then press "Digital /GRA" to return to data display.
After the measurement is completed, download the data, connect the base station and the field measurement magnetometer, and correct the diurnal variation;
Before or after the measurement, press the "AUX/LCD" key to enter the additional function display, where you can adjust the display brightness, output data, conduct factor test, lock the parameter setting function and reinstall the system.
Before or after the measurement, press the "NOTER" key to enter the annotation function display, where you can enter the annotation of the data file.
Before or after measurement, press the "INFO" key to enter the information function display, and you can input the information of the data file: measurement time, equipment serial number, measurement date, operator name and operation number.
Before or after the measurement, press the "Call" key to enter the data playback display.
(6) This is a very low frequency working state. Press "2" from (1) to enter the operation display, as shown in Figure 4-5-22.
Figure 4-5-22 VLF measurement main menu
Press the "Setup" key to enter the instrument setting display, as shown in Figure 4-5-23.
Figure 4-5-23 ENVI Very Low Frequency Mode Instrument Settings Menu
Press the "ENTER" key to ENTER (or press the "Enter" key from the main menu to enter) the very low frequency setting menu, as shown in Figure 4-5-24.
Figure 4-5-24 ENVI Very Low Frequency Mode Measurement Parameter Settings Menu
After setting, press ESC to return to (6), press the "Start" key to initialize the display, and automatically enter the measurement state after initialization.
During the measurement, if you need to view the data of a single frequency being saved, please press "1", "2" or "3".
Q box shows the operator's mass, preferably 5-6.
The S box shows the signal-to-noise ratio, and 9 is the best.
At any time, press "Digital /GRA" to display the profile of the last 178 point of the current survey line, press "Next" to display the precession attenuation signal of the last data, and then press "Digital /GRA" to return to data display.
Data playback and downloading are similar to magnetometer measurement.
(7) If you want to measure VLF and magnetic field at the same time, press the "3" key from (1), and the display will be as shown in Figure 4-5-25.
Figure 4-5-25 ENVI main menu is used to measure VLF and magnetic field at the same time.
Press the "Setup" key to enter the instrument setting display, as shown in Figure 4-5-26.
Figure 4-5-26 ENVI instrument setting menu for measuring extremely low frequency and magnetic field mode at the same time.
After setting, press ESC key to return to (7), and press "Start" key to start measurement.
During or after the measurement, the display, playback, download and correction of data are similar to the previous single measurement.