GEOSCIENCE AUSTRALIA Geological and energy implications of the Pine Creek region airborne electromagnetic (AEM) survey, Northern Territory, Australia M.A. Craig (editor) With contributions from: R.C. Brodie, M.T. Costelloe, M.A. Craig, D.K. Hutchinson, S. Jaireth, S.F. Liu, and N.C. Williams. Record 2011/18 GeoCat # 71854 APPLYING GEOSCIENCE TO AUSTRALIA’S MOST IMPORTANT CHALLENGES Geological and energy implications of the Pine Creek region airborne electromagnetic (AEM) survey, Northern Territory, Australia GEOSCIENCE AUSTRALIA RECORD 2011/18 By M.A. Craig (editor) With contributions from: R.C. Brodie1, M.T. Costelloe1, M.A. Craig1, D.K. Hutchinson2,4, S. Jaireth1, S.F. Liu1, and N.C. Williams2,3. 1. Airborne EM Project, Onshore Energy and Minerals Division, Geoscience Australia, GPO Box 387 Canberra ACT 2601 Australia. 2. Formerly Airborne EM Project, Onshore Energy and Minerals Division, Geoscience Australia, GPO Box 387 Canberra ACT 2601 Australia. 3. Present address: Ivanhoe Australia Ltd, Level 13, 484 St Kilda Road Melbourne VIC 3004 Australia. 4. Present address: Climate Change Research Centre, Level 4, Matthews Building, University of New South Wales, Sydney NSW 2052. Geological and energy implications of the Pine Creek airborne electromagnetic (AEM) survey, Northern Territory, Australia Department of Resources, Energy and Tourism Minister for Resources and Energy: The Hon. Martin Ferguson, AM MP Secretary: Mr Drew Clarke Geoscience Australia Chief Executive Officer: Dr Chris Pigram © Commonwealth of Australia (Geoscience Australia) 2011 With the exception of the Commonwealth Coat of Arms and where otherwise noted, all material in this publication is provided under a Creative Commons Attribution 3.0 Australia Licence (http://creativecommons.org/licenses/by/3.0/au/) Geoscience Australia has tried to make the information in this product as accurate as possible. However, it does not guarantee that the information is totally accurate or complete. Therefore, you should not solely rely on this information when making a commercial decision. ISSN 1448-2177 ISBN 978-1-921954-06-1 print ISBN 978-1-921954-05-4 web GeoCat # 71854 Bibliographic reference: Craig, M.A. ed. 2011. Geological and energy implications of the Pine Creek region airborne electromagnetic (AEM) survey, Northern Territory, Australia. Record 2011/18, 292 pp. Example chapter reference: Liu S.F. and Craig, M.A. Geology. In: Craig, M.A. ed . Geological and energy implications of the Pine Creek region airborne electromagnetic (AEM) survey, Northern Territory, Australia. Geoscience Australia Record 2011/18, pp. 35-54 Geological and energy implications of the Pine Creek airborne electromagnetic (AEM) survey, Northern Territory, Australia CONTENTS 1 INTRODUCTION...............................................................................................................................1 1.1 SURVEY DESIGN CHARACTERISTICS..............................................................................................2 1.2 SURVEY LOCATION........................................................................................................................3 1.3 SURVEY PURPOSE ..........................................................................................................................4 1.4 UNCONFORMITY–RELATED URANIUM DEPOSITS............................................................................7 1.4.1 Sandstone uranium deposits.................................................................................................7 1.5 OTHER MINERAL SYSTEMS.............................................................................................................7 1.6 GROUNDWATER SYSTEMS..............................................................................................................8 1.7 SURVEY ECONOMIC FRAMEWORK.................................................................................................9 1.8 SURVEY DESIGN CONSIDERATIONS ................................................................................................9 1.9 CLIMATE......................................................................................................................................10 1.10 NATIONAL PARKS........................................................................................................................10 1.11 TERRAIN (DRAPE)........................................................................................................................11 1.12 LAND ACCESS AND NATIVE TITLE ISSUES ...................................................................................12 1.13 OTHER NO FLY ZONES ................................................................................................................13 1.14 AIRCRAFT ACCESS .......................................................................................................................14 1.15 FORWARD MODELLING ................................................................................................................14 1.16 COMMUNICATION STRATEGY.......................................................................................................14 1.17 FINAL SURVEY DESIGN ................................................................................................................15 1.18 SURVEY PARTNERS, CONTRIBUTORS AND COST ...........................................................................17 1.19 CLIMATE......................................................................................................................................18 1.20 VEGETATION ...............................................................................................................................19 1.21 TOPOGRAPHY ..............................................................................................................................19 1.22 REFERENCES................................................................................................................................22 2 PREVIOUS AND CONCURRENT WORK...................................................................................23 2.1 GEOLOGICAL MAPPING ...............................................................................................................23 2.2 GEOPHYSICS ................................................................................................................................29 2.3 BOREHOLE DATA COMPILATION .................................................................................................30 2.4 REFERENCES................................................................................................................................34 3 GEOLOGY ........................................................................................................................................35 3.1 GEOLOGICAL FRAMEWORK..........................................................................................................35 3.1.1 Archean complexes.............................................................................................................37 3.1.2 Pine Creek Orogen.............................................................................................................38 3.1.2.1 Stratigraphy....................................................................................................................................39 3.1.2.2 Structural and tectonic history .......................................................................................................39 3.1.3 McArthur Basin and correlates..........................................................................................44 3.1.4 Fitzmaurice Basin...............................................................................................................44 3.1.5 Victoria Basin.....................................................................................................................44 3.1.6 Daly Basin..........................................................................................................................44 3.1.7 Bonaparte Basin.................................................................................................................44 3.1.8 Money Shoal Basin.............................................................................................................45 3.1.9 Cretaceous sediments.........................................................................................................45 3.2 REGOLITH GEOLOGY....................................................................................................................46 3.2.1 Introduction ........................................................................................................................46 3.2.2 What is regolith ..................................................................................................................46 3.2.3 Palaeoweathering and palaeoregolith ...............................................................................50 3.3 REFERENCES................................................................................................................................51 4 MINERAL SYSTEMS OVERVIEW ..............................................................................................55 4.1 INTRODUCTION ............................................................................................................................55 4.2 ARCHEAN MINERAL SYSTEMS......................................................................................................55