The gDAS32 Distributed Array system

The development of the gDAS32 Distributed Acquisition System has been built with a focus on acquisition flexibility and resolution; increasing the ADC to 32-bits of resolution, further decreasing instrument noise, and incorporating additional diagnostic and user interfaces through a radio (Bluetooth or other) connection to almost any hand-held device such as tablet or smartphone. Independent 2-channel units, running from a user-defined schedule, can be customized to synchronously acquire data at sample rates up to 32kHz for any array configuration without the need for inter-nodal communication, ideal for a host of custom arrays in diverse terrains.

Each gDAS32 acquisition system records time series data at various sample rates for two fully differential channels according to a pre-programmed schedule stored in memory controlled by synchronous GPS-PPS timing. This schedule defines the start time, sample rate, duration, and internal filtering options for each acquisition period. Any number of 2-channel gDAS32 units might be located on any survey grid, line or remote site installed with respective electric field dipoles and / or magnetic antennas.

gDAS instrumentation

gDAS32

data acquistion unit

gDAS32_aboveback.png

Each gDAS-32 unit comprises two 32-bit ADC’s for acquisition of data from grounded electric field dipoles, magnetometers, seismometers, geophones or other sensors with internal filtering and data storage driven by programmable acquisition schedules slaved to GPS-PPS timing.

gDAS iSense

current monitor sensor

The gDAS-iSense connects to a single gDAS-32 unit to monitor transmitter current signals for Induced Polarization / Resistivity, CSAMT, CSEM, TEM and other controlled source electromagnetic surveying. Dual, differential Hall sensors monitor the current inductively avoiding wired connections.

gDAS gTX

transmitter controller

AGT's gDAS-gTX transmitter controller provides GPS-PPS timed instruction to compatible transmitter equipment for almost any desired waveform for Induced Polarization / Resistivity, CSAMT, CSEM, TEM surveying. Manual initiation or with programmable schedules.

 

gDASPro data processing software

 

The gDASPro data processing software manages survey configurations, sensor & source information, gDAS-32 time series data file links and survey results stored in an SQLite database. The software menu system guides the user through data processing steps from survey design to output of section, plan maps and 3D visualizations as well as industry standard formats. Time series data files are assigned to survey source and sensors either manually or using structured field setup files for later batch processing, and on-screen editing as sections, maps and 3D plots

Magneto-Telluric data processing (MT / AMT / CSAMT)

• Tools for viewing time series data and spectra per sensor, time interval, frequency band

• Batch processing of electric and magnetic field data by station, line, area or time interval

• Robust automated and manual editing of apparent resistivity and impedance phase plots

• Plan maps per frequency band of Apparent Resistivity per component, Phase Tensor Ellipses, Polar Plots, Rose Diagrams

• Standard output to AVG an EDI files for inversion modelling

 IP / Resistivity data processing (TDIP / CR)

• Tools for viewing time series data and spectra per sensor, time interval, frequency band

• Batch processing of current monitor and electric field data by station, line, area or time interval

Automated and manual editing of time series data, Apparent Resistivity, Changeability (Time Domain) or Magnitude and Phase (CR)

• Pseudosections, plan maps and 3D views of survey parameters

• Standard output to AVG and DAT files  for inversion modelling

Transient Electromagnetic data processing (TEM)

• Tools for viewing time series data and spectra per sensor, time interval

• Batch processing of current monitor and electric field data by station, line, area or time interval

• Editing of Apparent Resistivity and Magnitude data vs Time plots

• Pseudosections, plan maps and 3D views of survey parameters

• Standard output to AVG and AMIRA format files  for inversion modelling

gDAS32 Mobile App

 

Our mobile app provides a user interface for real-time bluetooth or radio communication with the gDAS32 for viewing of sensor & source metrics, instrument autonomy and for initiating non-scheduled tasks.