AusMT / surveys / Western Tasmania 2016

Western Tasmania 2016 BBMT

Magnetotelluric survey · Tasmania · University of Tasmania

A broadband magnetotelluric transect of about 80 km was acquired across western Tasmania in January and February 2016, running roughly west to east along the Heemskirk Road and the Zeehan and Lyell Highways, from the west coast over the Devonian Heemskirk granite to the Lyell Highway inland.

About this survey

A broadband magnetotelluric transect of about 80 km was acquired across western Tasmania in January and February 2016, running roughly west to east along the Heemskirk Road and the Zeehan and Lyell Highways, from the west coast over the Devonian Heemskirk granite to the Lyell Highway inland. The line crosses the boundary between Precambrian Tyennan basement and the metalliferous Cambrian to Devonian Dundas-Fossey Trough. Crews worked from a Queenstown field base and began at the eastern end of the line. Thirty-four line sites were occupied at a mean spacing of 2.9 km. A remote-reference station about 5 km east of the easternmost proposed line site stayed deployed through the campaign. The work was University of Tasmania PhD fieldwork by Thomas Ostersen, supervised by Anya Reading (University of Tasmania) and Graham Heinson (University of Adelaide), proposed and funded by Mineral Resources Tasmania, with Geoscience Australia, the University of Adelaide and PassiveX Ltd contributing field personnel.

Instruments came from the ANSIR national Earth sounding instrument pool, funded by AuScope and maintained by the University of Adelaide. Each site ran a 24-bit six-channel PR6-24 Earth Data Logger sampling at 1000 Hz for 36 to 48 hours, recording Bx and By on two buried LEMI-120 induction coils and Ex and Ey across three Petiau-type lead chloride non-polarisable electrodes on dipoles of about 24 to 57 m against a nominal 50 m. Transfer functions were estimated with the bounded influence remote reference code BIRRP 5.1, driven from MTpy, in a high-frequency pass over a three-hour window and a low-frequency pass over the whole deployment, the two results then merged into one EDI file per site carrying 37 frequencies from 187.49998 Hz to 0.00061 Hz.

This package serves the 33 EDI transfer functions that were lodged with Mineral Resources Tasmania.

Data origin. The transfer functions served here are the 33 files of ProcessedData/Western_broadband_transect/processed_data/raw_edi.zip in Mineral Resources Tasmania lodgement GPCR2019_01 (MRT webdoc record id 115522, "Geoelectric Structure of the Tasmanian Lithosphere from Multi-Scale Magnetotelluric Data", Ostersen, T., dated 28 April 2021), released under Creative Commons Attribution 3.0 Australia. The raw time series behind them are held by NCI as 35 packed archives, site_300.zip to site_343.zip plus site_344_remote.zip, 75.1 GB in total, under DOI 10.25914/080v-2z48 within survey record 10.25914/be5s-at41.

Data and downloads

Stations (33)

Contributors and organisations

Organisation

University of Tasmania

Licence

CC BY 3.0 AU

Instruments

Earth Data PR6-24
LEMI LEMI-120
SDEC Petiau lead chloride electrode

Processing

BIRRP

Funding

Mineral Resources Tasmania
AuScope
National Collaborative Research Infrastructure Strategy (NCRIS)

Publications

Ostersen T C H (2021). Geoelectric Structure of the Tasmanian Lithosphere from Multi-Scale Magnetotelluric Data. PhD thesis, University of Tasmania. 10.25959/100.00037925

Ostersen T C H, Reading A M, Cracknell M J, Roach M, Duffett M L, Bombardieri D J, McNeill A, Fomin T, Brand K E, Thiel S, Boren G, Heinson G (2024). Resistivity anomalies in the shallow and deep crust beneath West Tasmania from a broadband magnetotelluric 2D transect. Exploration Geophysics. 10.1080/08123985.2024.2392802

Identifiers and provenance

Machine-readable survey record · catalogue schema mtcat 2.0