Magnetotelluric Survey in South-Eastern Mount Isa, QLD Australia

Magnetotelluric (MT) measures the natural variations of the Earth' magnetic and electrical (telluric) fields. The Audio-Magnetotelluric method (AMT) samples signal frequencies in the range of 20k Hz down to ~1Hz and provides data pertaining to the upper few kilometres of the Earth' crust. Broadband MT (BBMT) measures frequencies ranging from ~400 Hz down to periods of ~5000 s, providing measures of the conductivity of the crust. AMT and BBMT data were acquired at 138 stations with an interval of 2.5-5.0 km along a 690 km transect extending from Four Ways to Longreach in the South-eastern Mount Isa region. Full-waveform time series data were acquired and processed into frequency-domain transfer functions. Remote reference was applied to eliminate uncorrelated noise. After quality assurance, processed data were exported to industry-standard EDI files containing site info, impedance tensor, apparent resistivity, phase and vertical transfer function.