<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html> <head> <title>UTas ePrints - Inferring central McArthur Basin shape at HYC time: Integration of geophysical interpretation and geology using GIS</title> <script type="text/javascript" src="http://eprints.utas.edu.au/javascript/auto.js"><!-- padder --></script> <style type="text/css" media="screen">@import url(http://eprints.utas.edu.au/style/auto.css);</style> <style type="text/css" media="print">@import url(http://eprints.utas.edu.au/style/print.css);</style> <link rel="icon" href="/images/eprints/favicon.ico" type="image/x-icon" /> <link rel="shortcut icon" href="/images/eprints/favicon.ico" type="image/x-icon" /> <link rel="Top" href="http://eprints.utas.edu.au/" /> <link rel="Search" href="http://eprints.utas.edu.au/cgi/search" /> <meta content="Duffett, M.L." name="eprints.creators_name" /> <meta content="Roach, M." name="eprints.creators_name" /> <meta content="Leaman, D.E." name="eprints.creators_name" /> <meta content="Mark.Duffett@utas.edu.au" name="eprints.creators_id" /> <meta content="Michael.Roach@utas.edu.au" name="eprints.creators_id" /> <meta content="dleaman@lgeo.com.au" name="eprints.creators_id" /> <meta content="Munson, T." name="eprints.editors_name" /> <meta content="Ambrose, G." name="eprints.editors_name" /> <meta content="Tim.Munson@nt.gov.au" name="eprints.editors_id" /> <meta content="Greg.Ambrose@nt.gov.au" name="eprints.editors_id" /> <meta content="book_section" name="eprints.type" /> <meta content="2007-02-14" name="eprints.datestamp" /> <meta content="2008-01-23T04:54:23Z" name="eprints.lastmod" /> <meta content="show" name="eprints.metadata_visibility" /> <meta content="Inferring central McArthur Basin shape at HYC time: Integration of geophysical interpretation and geology using GIS" name="eprints.title" /> <meta content="pub" name="eprints.ispublished" /> <meta content="269999" name="eprints.subjects" /> <meta content="260108" name="eprints.subjects" /> <meta content="291004" name="eprints.subjects" /> <meta content="public" name="eprints.full_text_status" /> <meta content="Northern Territory, McArthur Basin, geographic information systems (GIS), sedimentary basins, reconstruction, mineral deposits, metallogenesis, Sedex, exhalative processes, base metals, geophysical interpretation, geological interpretation, regional mineral exploration" name="eprints.keywords" /> <meta content="Sediment-hosted metallogeny results from sedimentary basin fluid flow, which in turn, is controlled by the evolving architecture of the basin. Understanding and predicting the location of ore deposits therefore depends on knowledge of the three-dimensional geometry of the target basin through time (4-D basin architecture). However, quantitative basin analysis is severely handicapped in the absence of extensive seismic reflection data from the target terranes, such as the Proterozoic of northern Australia, host to a world-class base metal endowment. Geological mapping and regional potential field geophysical data, on the other hand, are widely available, but their interpretation in terms of 4-D basin architecture is not straightforward. GIS and geophysical modelling were deployed to assist. A GIS with 1:250 000-scale geological map and geochemical data was designed and implemented for a region in the McArthur Basin encompassing the giant HYC Zn-Pb-Ag deposit. The GIS incorporates geological attributes that encode depth information implicit in the stratigraphic column. This data structure, in conjunction with topological attributes, allows queries based on the stratigraphic relationships of spatial elements. An initial 3-D picture of the basin, relying solely on surface geological data and measured stratigraphic thicknesses, was developed by generation of layers comprising 'predicted' structure contour values for any given stratigraphic unit. This prediction is analogous to calculation of the theoretical Bouguer gravity value during reduction of gravity data. The predicted value (for example, of basement depth) does not necessarily indicate the true elevation of the surface being considered at a given location; rather, it is a baseline for comparison. Lateral variations from this baseline indicate departures of basin shape from 'layer-cake' geometry. By this mechanism, elements of the basin fill, lost due to deformation and erosion following terminal deposition, may be restored for comparative purposes. The development of stratigraphic topology enables automatic identification of the location and magnitude of unconformities on geological maps. These indicate areas and periods of uplift through the sedimentation history of the basin, from which fluid flow may have been topographically driven. Conversely, the distribution of unconformities circumscribes regions of more continuous sedimentation, where accommodation space was developed more consistently. Both gravity and magnetic data were forward modelled in an extensive interlocking array of cross-sectional 2-D profiles. Several basin units are resolvable from regional data using these methods. In particular, the HYC-hosting upper McArthur Group is distinguishable due to its carbonate-dominant composition, resulting in a positive density contrast. These interpretations, initially expressed as structure contours and isopachs (Leaman 1998), were interpolated into 3-D models of the present disposition of basin units. These may be compared directly with the basin unit depths and thicknesses 'predicted' from outcrop-derived data. Residuals, after removal of 'predicted' or 'layer-cake' McArthur Group thickness from the 'actual' (geophysically interpreted) present thickness, directly map the location and size of active sub-basins at the time of the formation of HYC mineralisation. The subbasins thus defined are congruent with indications from unconformity distribution. HYC's situation at the northeastern edge of one of these sub-basins is consistent with topographic and bounding growth fault control on the palaeohydrogeological regime that focused mineralising fluids in the vicinity of the deposit. Other sub-basin edges are indicated as sites of potential base metal mineralisation." name="eprints.abstract" /> <meta content="2007-02-08" name="eprints.date" /> <meta content="published" name="eprints.date_type" /> <meta content="Northern Territory Geological Survey Special Publication" name="eprints.series" /> <meta content="2" name="eprints.volume" /> <meta content="Northern Territory Geological Survey" name="eprints.publisher" /> <meta content="Darwin, NT" name="eprints.place_of_pub" /> <meta content="UNSPECIFIED" name="eprints.thesis_type" /> <meta content="TRUE" name="eprints.refereed" /> <meta content="Proceedings of the Central Australian Basins Symposium, Alice Springs, 16-18 August, 2005." name="eprints.book_title" /> <meta content="http://www.conferences.minerals.nt.gov.au/cabsproceedings" name="eprints.official_url" /> <meta content="Blewett R, 1993. The AGSO field geological note books - a user's guide. Australian Geological Survey Organisation, Record 1993/94. Bonham-Carter GF, Agterberg FP and Wright DF, 1990. Weights of evidence modelling: a new approach to mapping mineral potential: in Agterberg FP and Bonham-Carter GF (editors) 'Statistical Applications in the Earth Sciences.' Geological Survey of Canada, Paper 89-9, 171-183. D'Ercole C, Groves DI and Knox-Robinson CM, 2000. Using fuzzy logic in a Geographic Information System environment to enhance conceptually based prospectivity analysis of Mississippi Valley-type mineralisation. Australian Journal of Earth Sciences 47, 913-927. Duffett ML, 2000. Geophysical and GIS applications to exploration for Proterozoic sediment-hosted Zn- Pb mineralisation, northern Australia. PhD thesis, University of Tasmania. Duffett ML and Leaman DE, 1997. McArthur Basin architecture - a new perspective from geophysics and GIS. Exploration Geophysics 28, 39-42. Dunster JN, 1996. Sedimentology of the Lady Loretta Formation - a comparison of the regional setting to that of the Lady Loretta orebody: in Baker T et al (editors) 'MIC '96: The McArthur, Mt Isa, Cloncurry Minerals Province - New Developments in Metallogenic Research, Extended Conference Abstracts.' EGRU Contribution 55, 47-50. Etheridge MA, Rutland RWR and Wyborn LAI, 1987. Orogenesis and tectonic process in the early to middle Proterozoic of northern Australia: in Kroner A (editor) 'Proterozoic Lithospheric Evolution.' Geodynamics Series 17, 131-147. American Geophysical Union, Washington DC. Etheridge M and Wall V, 1994. Tectonic and structural evolution of the Australian Proterozoic. 12th Australian Geological Convention, Geological Society of Australia, Abstracts 37, 102-103. Hinman M, 1996. Constraints, timing and processes of stratiform base metal mineralization at the HYC Ag-Pb- Zn deposit, McArthur River: in Baker T et al (editors) 'MIC '96: The McArthur, Mt Isa, Cloncurry Minerals Province - New Developments in Metallogenic Research, Extended Conference Abstracts.' EGRU Contribution 55, 56-59. Hinman M, Wall V, and Heinrich C, 1994. The interplay between sedimentation, deformation and hydrothermal activity at the McArthur Pb-Zn (-Cu) deposit. 12th Australian Geological Convention, Geological Society of Australia Abstracts 37, 176-177. Jackson MJ, Muir MD and Plumb KA, 1987. Geology of the southern McArthur Basin, Northern Territory. BMR Bulletin 220. Jackson MJ, Sweet IP and Powell TG, 1988. Studies on petroleum geology and geochemistry of the middle Proterozoic McArthur Basin, northern Australia I: petroleum potential. Australian Petroleum Exploration Association, Journal 28, 283-302. Knox-Robinson CM, Robinson DC and Groves DI, 1992. The use of geographical information systems as a gold prospectivity mapping tool, with reference to the Yilgarn Block, Western Australia: Requirements and limitations: in Geological Applications of Geographic Information Systems (GIS). Australian Institute of Geoscientists, Bulletin 12, 71-82. Large RR, Bull SW, Selley D, Yang J, Cooke DR, Garven G and McGoldrick PJ, 2002. Controls on the formation of giant stratiform sediment-hosted Zn-Pb-Ag deposits: with particular reference to the north Australian Proterozoic: in Cooke, DR and Pongratz J (editors) 'Giant Ore Deposits: Characterization, Genesis, and Exploration.' CODES Special Publication 4, University of Tasmania, Hobart. Leaman DE, 1994. Criteria for evaluation of potential field interpretations. First Break 12, 181-191. Leaman DE, 1996. Are thick volcanic piles concealed in north Australian Proterozoic basins? Exploration Geophysics 27, 13-20. Leaman DE, 1997. Application of magnetic methods to deep basin structures. Exploration Geophysics 28, 97-105. Leaman DE, 1998. Structure, contents and setting of Pb-Zn mineralisation in the McArthur Basin, northern Australia. Australian Journal of Earth Sciences 45, 3-20. McClenaghan MP, Roach MJ and Bottrill RS, 1994. Structure of the GIS databases. Mineral Resources Tasmania, Report 1994/07 (unpublished). McGoldrick P and Large R, 1998. Proterozoic stratiform sediment-hosted Zn-Pb-Ag deposits. AGSO Journal of Geology and Geophysics 17(4), 189-196. Neudert M and McGeough M, 1996. A new tectonostratigraphic framework for the deposition of the upper McArthur Group, NT: in Baker T et al (editors) 'MIC '96: The McArthur, Mt Isa, Cloncurry Minerals Province - New Developments in Metallogenic Research, Extended Conference Abstracts.' EGRU Contribution 55, 90-93. Oehler JH and Logan RG, 1977. Microfossils, cherts and associated mineralization in the McArthur Deposit, NT, Australia. Economic Geology 72, 1393-1409. Page RW, Jackson MJ and Krassay AA, 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences 47, 431-459. Pietsch BA, Rawlings DJ, Creaser PM, Kruse PD, Ahmad M, Ferenczi PA and Findhammer TLR, 1991. Bauhinia Downs, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SE 53-03. Northern Territory Geological Survey, Darwin. Plumb KA, Ahmad M and Wygralak AS, 1990. Mid- Proterozoic basins of the North Australian Craton - regional geology and mineralisation: in Hughes FE (editor) Geology of the mineral deposits of Australia and Papua New Guinea. Volume 1. Australasian Institute of Mining and Metallurgy, Monograph 14, 881-902. Plumb KA and Wellman P, 1987. McArthur Basin, Northern Territory: mapping of deep troughs using gravity and magnetic anomalies. BMR Journal of Australian Geology and Geophysics 10, 243-252. 22 Duffett et al Rawlings DJ, 1994. Characterisation and correlation of volcanism in the McArthur Basin and Transitional Domain, NT: in Hallenstein CP (editor) 'AusIMM Annual Conference Technical Program Proceedings.' AusIMM Publication Series 5/94, 157-160. Rawlings DJ, 1999. Stratigraphic resolution of a multiphase intracratonic basin system: the McArthur Basin, northern Australia. Australian Journal of Earth Sciences 46, 703- 723. Rawlings DJ, 2007. Evolution of the Redbank Package: in Munson TJ and Ambrose GJ (editors) 'Petroleum and mineral potential of central Australian basins. Proceedings of the Central Australian Basins Symposium (CABS), Alice Springs, Northern Territory, 16-18 August, 2005.' Northern Territory Geological Survey, Special Publication 2 (this volume). Rogers J, 1996. Geology and tectonic setting of the Tawallah Group, southern McArthur Basin, Northern Territory. PhD thesis, University of Tasmania. Scott DL, Rawlings DJ, Page RW, Tarlowski CZ, Idnurm M, Jackson MJ and Southgate PN, 2000. Basement framework and geodynamic evolution of the Palaeoproterozoic superbasins of north-central Australia: an integrated review of geochemical, geochronological and geophysical data. Australian Journal of Earth Sciences 47, 341-380. Southgate PN, Bradshaw BE, Domagala J, Jackson MJ, Idnurm M, Krassay AA, Page RW, Sami TT, Scott DL, Lindsay JF, McConachie BA and Tarlowski C, 2000. Chronostratigraphic basin framework for Palaeoproterozoic rocks (1730-1575 Ma) in northern Australia and implications for base-metal mineralisation. Australian Journal of Earth Sciences 47(3), 461-483. Wright DF and Bonham-Carter GF, 1992. Two case studies for mapping mineral potential using weights-of-evidence modelling: Gold in Meguma Terrane, Nova Scotia and base metals in Snow Lake area, Manitoba: in 'Geological Applications of Geographic Information Systems (GIS).' Australian Institute of Geoscientists, Bulletin 12, 83-84. Wyborn LAI, Gallagher R and Mernagh TP, 1995. Using GIS for mineral potential evaluation in areas with few known mineral occurrences. Proceedings of the Second National Forum on GIS in the Geosciences. AGSO Record 1995/46, 199-211 . Yang Jianwen, Bull S and Large R, 2004. Numerical investigation of salinity in controlling ore-forming fluid transport in sedimentary basins: example of the HYC deposit, northern Australia. Mineralium Deposita 39, 1-19. " name="eprints.referencetext" /> <meta content="Duffett, M.L. and Roach, M. and Leaman, D.E. (2007) Inferring central McArthur Basin shape at HYC time: Integration of geophysical interpretation and geology using GIS. In: Proceedings of the Central Australian Basins Symposium, Alice Springs, 16-18 August, 2005. Northern Territory Geological Survey Special Publication, 2 . Northern Territory Geological Survey, Darwin, NT." name="eprints.citation" /> <meta content="http://eprints.utas.edu.au/668/1/P09_Duffett_et_al.pdf" name="eprints.document_url" /> <link rel="schema.DC" href="http://purl.org/DC/elements/1.0/" /> <meta content="Inferring central McArthur Basin shape at HYC time: Integration of geophysical interpretation and geology using GIS" name="DC.title" /> <meta content="Duffett, M.L." name="DC.creator" /> <meta content="Roach, M." name="DC.creator" /> <meta content="Leaman, D.E." name="DC.creator" /> <meta content="269999 Earth Sciences not elsewhere classified" name="DC.subject" /> <meta content="260108 Geotectonics" name="DC.subject" /> <meta content="291004 Spatial Information Systems" name="DC.subject" /> <meta content="Sediment-hosted metallogeny results from sedimentary basin fluid flow, which in turn, is controlled by the evolving architecture of the basin. Understanding and predicting the location of ore deposits therefore depends on knowledge of the three-dimensional geometry of the target basin through time (4-D basin architecture). However, quantitative basin analysis is severely handicapped in the absence of extensive seismic reflection data from the target terranes, such as the Proterozoic of northern Australia, host to a world-class base metal endowment. Geological mapping and regional potential field geophysical data, on the other hand, are widely available, but their interpretation in terms of 4-D basin architecture is not straightforward. GIS and geophysical modelling were deployed to assist. A GIS with 1:250 000-scale geological map and geochemical data was designed and implemented for a region in the McArthur Basin encompassing the giant HYC Zn-Pb-Ag deposit. The GIS incorporates geological attributes that encode depth information implicit in the stratigraphic column. This data structure, in conjunction with topological attributes, allows queries based on the stratigraphic relationships of spatial elements. An initial 3-D picture of the basin, relying solely on surface geological data and measured stratigraphic thicknesses, was developed by generation of layers comprising 'predicted' structure contour values for any given stratigraphic unit. This prediction is analogous to calculation of the theoretical Bouguer gravity value during reduction of gravity data. The predicted value (for example, of basement depth) does not necessarily indicate the true elevation of the surface being considered at a given location; rather, it is a baseline for comparison. Lateral variations from this baseline indicate departures of basin shape from 'layer-cake' geometry. By this mechanism, elements of the basin fill, lost due to deformation and erosion following terminal deposition, may be restored for comparative purposes. The development of stratigraphic topology enables automatic identification of the location and magnitude of unconformities on geological maps. These indicate areas and periods of uplift through the sedimentation history of the basin, from which fluid flow may have been topographically driven. Conversely, the distribution of unconformities circumscribes regions of more continuous sedimentation, where accommodation space was developed more consistently. Both gravity and magnetic data were forward modelled in an extensive interlocking array of cross-sectional 2-D profiles. Several basin units are resolvable from regional data using these methods. In particular, the HYC-hosting upper McArthur Group is distinguishable due to its carbonate-dominant composition, resulting in a positive density contrast. These interpretations, initially expressed as structure contours and isopachs (Leaman 1998), were interpolated into 3-D models of the present disposition of basin units. These may be compared directly with the basin unit depths and thicknesses 'predicted' from outcrop-derived data. Residuals, after removal of 'predicted' or 'layer-cake' McArthur Group thickness from the 'actual' (geophysically interpreted) present thickness, directly map the location and size of active sub-basins at the time of the formation of HYC mineralisation. The subbasins thus defined are congruent with indications from unconformity distribution. HYC's situation at the northeastern edge of one of these sub-basins is consistent with topographic and bounding growth fault control on the palaeohydrogeological regime that focused mineralising fluids in the vicinity of the deposit. Other sub-basin edges are indicated as sites of potential base metal mineralisation." name="DC.description" /> <meta content="Northern Territory Geological Survey" name="DC.publisher" /> <meta content="Munson, T." name="DC.contributor" /> <meta content="Ambrose, G." name="DC.contributor" /> <meta content="2007-02-08" name="DC.date" /> <meta content="Book Chapter" name="DC.type" /> <meta content="PeerReviewed" name="DC.type" /> <meta content="application/pdf" name="DC.format" /> <meta content="http://eprints.utas.edu.au/668/1/P09_Duffett_et_al.pdf" name="DC.identifier" /> <meta content="http://www.conferences.minerals.nt.gov.au/cabsproceedings" name="DC.relation" /> <meta content="Duffett, M.L. and Roach, M. and Leaman, D.E. (2007) Inferring central McArthur Basin shape at HYC time: Integration of geophysical interpretation and geology using GIS. In: Proceedings of the Central Australian Basins Symposium, Alice Springs, 16-18 August, 2005. 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border: solid 1px #ccc; padding: 3px"><tr> <td align="left"><a href="http://eprints.utas.edu.au/cgi/users/home">Login</a> | <a href="http://eprints.utas.edu.au/cgi/register">Create Account</a></td> <td align="right" style="white-space: nowrap"> <form method="get" accept-charset="utf-8" action="http://eprints.utas.edu.au/cgi/search" style="display:inline"> <input class="ep_tm_searchbarbox" size="20" type="text" name="q" /> <input class="ep_tm_searchbarbutton" value="Search" type="submit" name="_action_search" /> <input type="hidden" name="_order" value="bytitle" /> <input type="hidden" name="basic_srchtype" value="ALL" /> <input type="hidden" name="_satisfyall" value="ALL" /> </form> </td> </tr></table></td></tr> <tr> <td class="toplinks"><!-- InstanceBeginEditable name="content" --> <div align="center"> <table width="720" class="ep_tm_main"><tr><td align="left"> <h1 class="ep_tm_pagetitle">Inferring central McArthur Basin shape at HYC time: Integration of geophysical interpretation and geology using GIS</h1> <p style="margin-bottom: 1em" class="not_ep_block"><span class="person_name">Duffett, M.L.</span> and <span class="person_name">Roach, M.</span> and <span class="person_name">Leaman, D.E.</span> (2007) <xhtml:em>Inferring central McArthur Basin shape at HYC time: Integration of geophysical interpretation and geology using GIS.</xhtml:em> In: Proceedings of the Central Australian Basins Symposium, Alice Springs, 16-18 August, 2005. Northern Territory Geological Survey Special Publication, 2 . Northern Territory Geological Survey, Darwin, NT.</p><p style="margin-bottom: 1em" class="not_ep_block"></p><table style="margin-bottom: 1em" class="not_ep_block"><tr><td valign="top" style="text-align:center"><a onmouseover="EPJS_ShowPreview( event, 'doc_preview_681' );" href="http://eprints.utas.edu.au/668/1/P09_Duffett_et_al.pdf" onmouseout="EPJS_HidePreview( event, 'doc_preview_681' );"><img alt="[img]" src="http://eprints.utas.edu.au/style/images/fileicons/application_pdf.png" class="ep_doc_icon" border="0" /></a><div class="ep_preview" id="doc_preview_681"><table><tr><td><img alt="" src="http://eprints.utas.edu.au/668/thumbnails/1/preview.png" class="ep_preview_image" border="0" /><div class="ep_preview_title">Preview</div></td></tr></table></div></td><td valign="top"><a href="http://eprints.utas.edu.au/668/1/P09_Duffett_et_al.pdf"><span class="ep_document_citation">PDF</span></a> - Requires a PDF viewer<br />2737Kb</td></tr></table><p style="margin-bottom: 1em" class="not_ep_block">Official URL: <a href="http://www.conferences.minerals.nt.gov.au/cabsproceedings">http://www.conferences.minerals.nt.gov.au/cabsproceedings</a></p><div class="not_ep_block"><h2>Abstract</h2><p style="padding-bottom: 16px; text-align: left; margin: 1em auto 0em auto">Sediment-hosted metallogeny results from sedimentary basin fluid flow, which in turn, is controlled by the evolving architecture of the basin. Understanding and predicting the location of ore deposits therefore depends on knowledge of the three-dimensional geometry of the target basin through time (4-D basin architecture). However, quantitative basin analysis is severely handicapped in the absence of extensive seismic reflection data from the target terranes, such as the Proterozoic of northern Australia, host to a world-class base metal endowment. Geological mapping and regional potential field geophysical data, on the other hand, are widely available, but their interpretation in terms of 4-D basin architecture is not straightforward. GIS and geophysical modelling were deployed to assist. A GIS with 1:250 000-scale geological map and geochemical data was designed and implemented for a region in the McArthur Basin encompassing the giant HYC Zn-Pb-Ag deposit. The GIS incorporates geological attributes that encode depth information implicit in the stratigraphic column. This data structure, in conjunction with topological attributes, allows queries based on the stratigraphic relationships of spatial elements. An initial 3-D picture of the basin, relying solely on surface geological data and measured stratigraphic thicknesses, was developed by generation of layers comprising 'predicted' structure contour values for any given stratigraphic unit. This prediction is analogous to calculation of the theoretical Bouguer gravity value during reduction of gravity data. The predicted value (for example, of basement depth) does not necessarily indicate the true elevation of the surface being considered at a given location; rather, it is a baseline for comparison. Lateral variations from this baseline indicate departures of basin shape from 'layer-cake' geometry. By this mechanism, elements of the basin fill, lost due to deformation and erosion following terminal deposition, may be restored for comparative purposes. The development of stratigraphic topology enables automatic identification of the location and magnitude of unconformities on geological maps. These indicate areas and periods of uplift through the sedimentation history of the basin, from which fluid flow may have been topographically driven. Conversely, the distribution of unconformities circumscribes regions of more continuous sedimentation, where accommodation space was developed more consistently. Both gravity and magnetic data were forward modelled in an extensive interlocking array of cross-sectional 2-D profiles. Several basin units are resolvable from regional data using these methods. In particular, the HYC-hosting upper McArthur Group is distinguishable due to its carbonate-dominant composition, resulting in a positive density contrast. These interpretations, initially expressed as structure contours and isopachs (Leaman 1998), were interpolated into 3-D models of the present disposition of basin units. These may be compared directly with the basin unit depths and thicknesses 'predicted' from outcrop-derived data. Residuals, after removal of 'predicted' or 'layer-cake' McArthur Group thickness from the 'actual' (geophysically interpreted) present thickness, directly map the location and size of active sub-basins at the time of the formation of HYC mineralisation. The subbasins thus defined are congruent with indications from unconformity distribution. HYC's situation at the northeastern edge of one of these sub-basins is consistent with topographic and bounding growth fault control on the palaeohydrogeological regime that focused mineralising fluids in the vicinity of the deposit. Other sub-basin edges are indicated as sites of potential base metal mineralisation.</p></div><table style="margin-bottom: 1em" cellpadding="3" class="not_ep_block" border="0"><tr><th valign="top" class="ep_row">Item Type:</th><td valign="top" class="ep_row">Book Chapter</td></tr><tr><th valign="top" class="ep_row">Keywords:</th><td valign="top" class="ep_row">Northern Territory, McArthur Basin, geographic information systems (GIS), sedimentary basins, reconstruction, mineral deposits, metallogenesis, Sedex, exhalative processes, base metals, geophysical interpretation, geological interpretation, regional mineral exploration</td></tr><tr><th valign="top" class="ep_row">Subjects:</th><td valign="top" class="ep_row"><a href="http://eprints.utas.edu.au/view/subjects/269999.html">260000 Earth Sciences > 269900 Other Earth Sciences > 269999 Earth Sciences not elsewhere classified</a><br /><a href="http://eprints.utas.edu.au/view/subjects/260108.html">260000 Earth Sciences > 260100 Geology > 260108 Geotectonics</a><br /><a href="http://eprints.utas.edu.au/view/subjects/291004.html">290000 Engineering and Technology > 291000 Geomatic Engineering > 291004 Spatial Information Systems</a></td></tr><tr><th valign="top" class="ep_row">Collections:</th><td valign="top" class="ep_row">UNSPECIFIED</td></tr><tr><th valign="top" class="ep_row">ID Code:</th><td valign="top" class="ep_row">668</td></tr><tr><th valign="top" class="ep_row">Deposited By:</th><td valign="top" class="ep_row"><span class="ep_name_citation"><span class="person_name">Dr Mark Duffett</span></span></td></tr><tr><th valign="top" class="ep_row">Deposited On:</th><td valign="top" class="ep_row">14 Feb 2007</td></tr><tr><th valign="top" class="ep_row">Last Modified:</th><td valign="top" class="ep_row">23 Jan 2008 15:54</td></tr><tr><th valign="top" class="ep_row">ePrint Statistics:</th><td valign="top" class="ep_row"><a target="ePrintStats" href="/es/index.php?action=show_detail_eprint;id=668;">View statistics for this ePrint</a></td></tr></table><p align="right">Repository Staff Only: <a href="http://eprints.utas.edu.au/cgi/users/home?screen=EPrint::View&eprintid=668">item control page</a></p> </td></tr></table> </div> <!-- InstanceEndEditable --></td> </tr> <tr> <td><!-- #BeginLibraryItem "/Library/footer_eprints.lbi" --> <table width="795" border="0" align="left" cellpadding="0" class="footer"> <tr valign="top"> <td colspan="2"><div align="center"><a href="http://www.utas.edu.au">UTAS home</a> | <a href="http://www.utas.edu.au/library/">Library home</a> | <a href="/">ePrints home</a> | <a href="/contact.html">contact</a> | <a href="/information.html">about</a> | <a href="/view/">browse</a> | <a href="/perl/search/simple">search</a> | <a href="/perl/register">register</a> | <a href="/perl/users/home">user area</a> | <a href="/help/">help</a></div><br /></td> </tr> <tr><td colspan="2"><p><img src="/images/eprints/footerline.gif" width="100%" height="4" /></p></td></tr> <tr valign="top"> <td width="68%" class="footer">Authorised by the University Librarian<br /> © University of Tasmania ABN 30 764 374 782<br /> <a href="http://www.utas.edu.au/cricos/">CRICOS Provider Code 00586B</a> | <a href="http://www.utas.edu.au/copyright/copyright_disclaimers.html">Copyright & Disclaimers</a> | <a href="http://www.utas.edu.au/accessibility/index.html">Accessibility</a> | <a href="http://eprints.utas.edu.au/feedback/">Site Feedback</a> </td> <td width="32%"><div align="right"> <p align="right" class="NoPrint"><a href="http://www.utas.edu.au/"><img src="http://www.utas.edu.au/shared/logos/unioftasstrip.gif" alt="University of Tasmania Home Page" width="260" height="16" border="0" align="right" /></a></p> <p align="right" class="NoPrint"><a href="http://www.utas.edu.au/"><br /> </a></p> </div></td> </tr> <tr valign="top"> <td><p> </p></td> <td><div align="right"><span class="NoPrint"><a href="http://www.eprints.org/software/"><img src="/images/eprintslogo.gif" alt="ePrints logo" width="77" height="29" border="0" align="bottom" /></a></span></div></td> </tr> </table> <!-- #EndLibraryItem --> <div align="center"></div></td> </tr> </table> </body> </html>