AusMT survey data — licence and attribution
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Licence:     CC-BY-4.0
Licence URL: https://creativecommons.org/licenses/by/4.0/
Licensor:    Geoscience Australia
Year:        2010

Attribution (cite as):
  Sourced from Geoscience Australia eCat record 75099, L196 Youanmi (Yilgarn Craton) Magnetotelluric Survey, delivered as 75099_Youanmi.zip and licensed CC BY 4.0. The header dates of the served copies have been repaired; the delivered files are kept unaltered under provenance/as-delivered/ and every change is recorded in the served file itself.

This LICENSE.txt travels with the data files in this archive. The transfer functions were
distributed via the AusMT portal, which serves only openly licensed Australian magnetotelluric
releases; the licence above is the custodian's, set in the survey's survey.yaml. Reuse under the
terms of that licence (https://creativecommons.org/licenses/by/4.0/).

Changes were made: The served set is 183 of the 184 delivered soundings: YMB057 is withheld under owner ruling 2026-09-19 because its estimate is defective rather than its convention, and its delivered file is kept unaltered under provenance/as-delivered/ with the evidence and the ruling recorded in provenance/served-files.json. The ACQDATE and FILEDATE values of all 183 served files were rewritten from day/month/year into ISO 8601 by _tools/repair_edi_header_dates.py, and a nine line record was inserted after each file's >INFO line naming the delivered file, its path in the delivery, its sha256, the kept copy, the defect, the change, the basis and the ruling. No other byte of any file was changed: no data block, no other header line, no padding and no line ending, proved file by file against provenance/as-delivered/. The basis is that the delivery writes day first: 110 of the 184 ACQDATE values and all 184 FILEDATE values carry a day above 12 and neither field ever carries a month above 12, the four delivered site lists repeat the same strings on all 184 rows, and section 4.4 of the survey report prints 31/07/2010 on page 11 for YMB051 and YMB052, whose three digit year 201 was resolved to 2010 only because the caller named that value. Read as delivered, mt_metadata took 69 starts month first and clamped those two to 1677-09-21; read on the served copies, all 183 station starts and all 183 provenance.creation_time values equal the day-first header date. The date ruling is owner ruling 2026-09-19, which fixes the Youanmi dates before upload under the repair rule of 2026-09-18. No number, no frame and no gate verdict is altered by the repair.. AusMT serves derived renditions (canonical EMTF XML; MTH5 where available) generated from the deposited files; per-station conditioning notes are recorded in the machine-readable products.
