24-Bit Geophysical EM Measurement System
As in seismics, technological advances in electromagnetic recording systems have emphasised the requirementfor simultaneous multi-channel data acquisition.
The Multi-Method Network Geophysical Measurement System GMS-07 is the result of over 30 years ofmetronix´s experience in the design and manufacture of electromagnetic geophysical instruments. Theelectric (E) and/or magnetic field (H) sensors are connected directly to the ADU-07 (Analog/Digital SignalConditioning Unit), which is the core unit of this system. Multiple ADU-07 units can be connected to anetwork using simple, light-weight and inexpensive network cable or Wireless LAN.
Each ADU-07 can be operated as a stand alone system, in a network or as part of an array in which eachunit is synchronized by its in-built GPS clock.
The ADU-07e electronics are housed in a small waterproof box only 7,1kg in weight. It comprises the completecircuitry for analog signal conditioning, 24 Bit A/D conversion and data storage. A very precise GPScontrolledtime base guarantees synchronous recordings even under difficult GPS reception conditions.
The ADU-07e can be tailored according to the user´s requirements.
So the ADU contains 10 slots which can be equipped with 2 different types of A/D converter boards. A/Dconverter Type L is optimized for lower frequency recordings in a range from DC up to 500Hz while thesecond type H is optimized for high frequency recordings in a signal range from 1Hz up to 250kHz. Forinstance a broadband standard ADU-07 is equipped with 5 low-frequency and 5 high-frequency A/D converter modules. It is possible to obtain high-frequency soundings during running low-frequency recording.
Different types of sensors can be connected to the ADU and can even be operated in parallel. Example: Afluxgate sensor is connected for low-frequency sounding and induction coils cover the higher frequencyrange simultaneously.
The ADU-07 has a built-in web server. All necessary setups to run a measurement are controlled by the webinterface and can be accessed by any web browser; no software needs to be installed on your laptop orPDA. The software MAPROS (free) performs standard and remote reference processing of the time seriesdata using robust algorithms. Online processing inside the ADU-07 with unattended data publishing on theADU’s web server is under construction.
Using an external GPS controlled transmitter the ADU-07 provides CSAMT/CSEMM recordings with realtimestacking.
Single Site Configuration
In this configuration a single ADU-07 runs either in a stand alone mode and records the data according to a time schedule pre-programmed on its internal flashdisk. For highest performance an external computer can control the ADU via the USB 2.0 interface; in the latter case incoming data is processed and displayed in real time.
Multiple Site Configuration
In this configuration several ADU-07 systems are synchronized by their built-in GPS clocks, and they record the data synchronously. A typical application for this configuration is the Remote Reference method or Array Mapping. This arrangement is used for a grid with wide-spaced recording sites where cabling is impractical or cannot be handled economically.
Multiple ADUs are connected to a network by cable or WLAN. A typical example for this configuration is E-MAP or field setups, where a close-spaced station grid is required.
BROADBAND MAGNETOTELLURIC 10 Channels ADU-07e
ALL IN ONE METHODS (MT, AMT, CSAMT, RMT)
|Automatically off mode when overheated with temperature > 70oC and be automatically on again when the temperature of main unit is getting lower|
|Continuing to keep data on low battery mode and show the data when the main unit in on mode again (data is not loss)|
|Frequency Range||DC to 250 KHz (DC to 250,000 Hz)|
|Number of Channels||10 Channels per main unit|
|2 bands (LF DC-512 Hz ; HF 1 Hz – 250KHz)
Sub-bands are created by digital filtering
Both bands can be recorded simultaneously
|A/D conversion||24 Bit (max. data rate 2048 samples/sec) LF Board
24 Bit (max. data rate 524,288 samples/sec) LF Board
|Dynamic Range||>130 dB|
|System controller||32 bit embedded controller, Linux|
|Storage media||Internal compact flash up to 4 GB or more, USB devices|
|Test facilities||Automatic power up self test of all important system functions including sensors and display of result on the instrument. Automatic creation of log file|
|E-Field connector||Input resistance >10M Ohm, ODU-G32KON-T06QP00-000
ODU S22KON-T06MPL0-4000 (E-Field cable plug)
|H-field connector||Input Resistance 20 kOhm, socket ODU G32KON- T10QJ00-000
ODU S22KON-T10MJG0-7000 (H-Field cable plug)
|Multipurpose connector (E/H)||Input Resistance > 10 Mohm (E), 20 kOhm (H); ODU G33KON-T30QF00-000 ODU S23KOC-T30MFG0-7000 (cable plug)|
|Network Connection||Standard 100 Mbit Twisted Pair, USB 1.1, 2.0 (wireless/Bluetooth)|
|Synchronization||GPS clock +/- 30ns to satellite reference. Station position is also determined and stored|
|Interfaces||Network, Magnetometers, E- Field lines 2 battery inputs, GPS antenna, USB, Wireless|
|Case||Ruggedized, Waterproof Polycarbonate Case|
|Weight||Appr. 7.1 kg|
|External Dimensions||400 x 330 x 170 mm|
|Power Consumptions||Appr. 3-5 W (LF); 12 -20 W
HF @ 96kHz up to 524 kHz sample rate
|Operator Temperature Range||-40°C to + 70°C|
|Loss of GPS Signal||Still doing measurement|
|Weak Battery Power||Data will be saved & secured and will be shown when unit is on|
|Download Data||Data can be taken during measurement|
|Software Processing||To be updated every year & FREE|
|Processing Data||Can be set up from 8 points to be 100 points (using Mapros in frequency range : 10 eo and 10 e -1|
|Additional Feature||E-MAP feature : with one ADU-07e and 2 satellite Box can measure 4 point in one night|