Defining the Eyre Conductivity Anomaly with the Tumby Bay MT transect

Kate Robertson; Ben Kay; Lachlan Loader; Graham Heinson; Stephan Thiel

doi:10.1080/22020586.2019.12072992

2nd Australasian Exploration Geoscience Conference: Data to Discovery

ISSN: 2202-0586
E-ISSN:

oa Defining the Eyre Conductivity Anomaly with the Tumby Bay MT transect
Authors Kate Robertson^a,b,c, Ben Kay^c, Lachlan Loader^c, Graham Heinson^c and Stephan Thiel^b
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^a [email protected] ^b Geological Survey of South Australia, , GPO Box 320, Adelaide, , SA, 5001 ^c School of Physical Sciences, The University of Adelaide, , Adelaide, , SA, 5005
Publisher: Australian Society of Exploration Geophysicists
Source: ASEG Extended Abstracts, Volume 2019, Issue 2nd Australasian Exploration Geoscience Conference: Data to Discovery, Dec 2019, p. 1 - 3
DOI: https://doi.org/10.1080/22020586.2019.12072992
- Published online: 01 Dec 2019

Abstract

Summary

We present results of 36 broadband magnetotelluric (MT) stations along a 70 km ENE-WSW profile across the southern Eyre Peninsula, South Australia. The transect crosses the Eyre Peninsula Anomaly (EPA), first identified by induction arrows, and visualised in 3D from AusLAMP resistivity models. The significantly smaller site spacing of the Tumby Bay MT profile compared to AusLAMP (2 km instead of 55 km) has allowed us to image the EPA in high resolution which has defined the EPA into a very conductive (< 0.1Ωm) region from depths ~2-17 km and a width of about 30 km. At greater depths (~17-22 km) the conductor becomes widespread across the transect but less conductive (~30 Ωm). On the eastern third of the profile, upper crustal conductive fluid pathways are identified and may connect to the main body of the EPA.

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References

Becken, M. and Burkhardt, H., 2004, An ellipticity criterion in magnetotelluric tensor analysis, Geophysical Journal International, 159(1) 69–82.
Chave, A.D. and Thomson, D.J., 2004, Bounded influence magnetotelluric response function estimation, Geophysical Journal Internationa, 157, 988-1006.
Constable, S.C, Parker, R.L and Constable, C.G., 1987. Occams’ inversion: A practical algorithm for generatlng smooth models from electromagnetic sounding data, Geophysics, 52(3), 289-300.
Curtis, S. and Thiel, S., 2019, Identifying lithospheric boundaries using magnetotellurics and Nd isotope geochemistry: An example from the Gawler Craton, Australia, Precambrian Research, 320, 403-423.
Kay, B. 2018, Curnamona MT transect, honours thesis, University of Adelaide.
Milligan, PR., White, A. and Chamalaun, F., 1989, Extension of the Eyre Peninsula Conductivity Anomaly, Exploration Geophysics, 20, 187-190.
Popkov, I., 2000, Electromagnetic investigation of the Eyre Peninsula conductivity, Exploration Geophysics, 31:1-2, 187-191.
Robertson, K.E., Heinson, G.S. and Thiel, S., 2016, Lithospheric reworking at the Proterozoic–Phanerozoic transition of Australia imaged using AusLAMP Magnetotelluric data, Earth and Planetary Science Letters, 452, 27-35.
Thiel, S., Heinson, G. and White, A., 2005, Tectonic evolution of the southern Gawler Craton, South Australia, from electromagnetic sounding, Australian Journal of Earth Sciences, 52, 887-896.
Thiel, S., Heinson, G., Reid, A. and Robertson, K., 2016, Insights into lithospheric architecture, fertilisation and fluid pathways from AusLAMP MT: ASEG Extended Abstracts.
Wang, L., Chamalaun, F., 1995. A magnetotelluric traverse across the Adelaide Geosyncline. Exploration Geophysics, 26, 539–546.
Wessel, P., W. H. F. Smith, R. Scharroo, J. F. Luis, and F. Wobbe, 2013, Generic Mapping Tools: Improved version released, EOS Trans. AGU, 94, 409-410.

/content/journals/10.1080/22020586.2019.12072992

Article Type: Research Article

Keyword(s): conductivity anomaly; electrical resistivity; Eyre Peninsular; lithosphere; Magnetotellurics

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