{
 "schema": "ausmt-survey-metadata",
 "version": "0.1",
 "survey_id": "carpentaria-south-1995",
 "title": "Carpentaria Array 1995 (Southern Sub-array)",
 "dates": {
  "coverage": {
   "year_start": 1995,
   "year_end": 1995
  }
 },
 "abstract": "The arrays of 1976 and 1977 mapped the Southwest Queensland Anomaly but did not show how far north it ran. Dennis Woods and Frederick (Ted) Lilley proposed that the current concentrated along the western edge of the Eromanga Basin might continue north to form a conducting path across the continent, and Francois Chamalaun and Charlie Barton, reading the AWAGS array of 1989 - 90, suggested that path extended north into the Gulf of Carpentaria. In 1995 the Australian National University and Flinders University, under the ANU Institute of Advanced Studies' collaboration scheme and led in the field by Ted Lilley and Francois Chamalaun, set out to map that northward extension with forty-three magnetometer sites across northern Queensland, from the Mount Isa Inlier to the Pacific coast, at an average spacing of 100 km. Twenty-one Flinders digital fluxgate magnetometers, recording three components once a minute, occupied the north-west from June to August and were then moved to the north-east for September to November, with Trenton kept running as the tie between the two stages and the Australian Geological Survey Organisation's Charters Towers observatory recording throughout as the reference for both. Liejun Wang analysed the records for his doctoral thesis.\nThe second stage occupied twenty-two sites in the north-east, together with the observatory, from Richmond and Hughenden east across the Great Artesian Basin and the Georgetown and Mount Surprise country to Tully, Townsville, Proserpine and Carmila Beach on the coast. The horizontal variations were alike from site to site, which showed the source field was uniform. The vertical variations differed systematically. They were strongest at the coastal sites, Carmila Beach, Proserpine, Townsville and Tully, and weakened inland, which is the coast effect. Wang computed the response functions against the observatory by a robust method and mapped them as contours and induction arrows; the values he tabulates run from 360 to 27,300 s. A line of zero response separated arrows pointing east from arrows pointing west, which confirmed a good conductor running roughly north to south along the boundary between the Mount Isa Inlier and the Great Artesian Basin. In the first stage's records the vertical variations at Inlier sites were reversed in phase against those in the Great Artesian Basin. The two stages together traced that conductor northwards, and it is now called the Carpentaria Anomaly. On AusMT's reading the western stations, Trenton, Richmond, Rimbanda and Surbiton, are the ones that bear on the anomaly itself; east of 144 degrees Wang read the eastward arrows as the coast effect. Wang's inversions put the conductor within the basin sediments, 1 to 5 ohm m along the inlier's margin, most likely saline aquifers where the geothermal gradient is high, and his thesis concluded that the anomaly joins the Southwest Queensland Anomaly to the south and that to the north it remains unmapped, possibly running up the west of Cape York rather than straight into the Gulf. A magnetotelluric profile crossed the anomaly in 1997. Francois Chamalaun, Ted Lilley and Liejun Wang published the map in 1999 as Mapping the Carpentaria conductivity anomaly in northern Australia, and the Geological Survey of Queensland re-surveyed the anomaly with magnetotellurics in 2023 and 2024.\nThe transfer functions survive in two places, Appendix A.4 of Wang's thesis and his Australian Electromagnetic Database, at seventeen periods for every station but Greenvale, which has sixteen. The full station names survive only in Wang's Table 6.2.\nThe served numbers are tipper transfer functions, the real and quadrature induction arrows for twenty-three stations at seventeen periods from 360 to 27,300 s, Greenvale at sixteen. Liejun Wang computed them by the robust method of Chave, Thomson and Ander (1987) against the Charters Towers observatory and printed them in Appendix A.4 of his 1998 Australian National University thesis (hdl:1885/145955, printed pages 170 to 177); the same values, differing only in the sign convention for the azimuths, stand as reference code 8 of Liejun Wang's Australian Electromagnetic Database, which is the source served here. Wang reported the errors as under one per cent, but neither the appendix nor the register prints them, so no uncertainties travel with the served values; the coordinates are the register's, which agree with Wang's Table 6.2 to better than 2 km at every station but Trenton, where the two differ by about 4.4 km. The original recordings are not held, surviving only as two stacked magnetogram figures in the thesis.",
 "subjects": [
  {
   "code": "370602",
   "scheme": "ANZSRC-FoR-2020",
   "label": "Electrical and electromagnetic methods in geophysics",
   "uri": "https://linked.data.gov.au/def/anzsrc-for/2020/370602"
  }
 ],
 "creators": [
  {
   "name": "F. H. Chamalaun",
   "name_type": "person"
  },
  {
   "name": "F. E. M. Lilley",
   "name_type": "person"
  },
  {
   "name": "Liejun Wang",
   "name_type": "person"
  }
 ],
 "organisations": [
  {
   "name": "Flinders University",
   "ror": "https://ror.org/01kpzv902",
   "roles": [
    "custodian"
   ],
   "primary_custodian": true
  },
  {
   "name": "Australian National University",
   "ror": "https://ror.org/019wvm592",
   "roles": [
    "custodian"
   ]
  }
 ],
 "rights": {
  "license": "CC-BY-4.0",
  "access": "open"
 },
 "relationships": [
  {
   "identifier": "hdl:1885/145955",
   "identifier_type": "Handle",
   "relation": "IsDocumentedBy"
  },
  {
   "identifier": "https://ausmt.auscope.org.au/collections/australia-legacy-gds",
   "identifier_type": "URL",
   "relation": "IsPartOf"
  }
 ],
 "provenance": {
  "generated": "2026-09-09T06:47:27Z",
  "generator": "ausmt/extract.build_portal 0.2.1"
 }
}