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UQ-SDAAP | Sequence Stratigraphy of the Precipice Sandstone and Evergreen Formation in the Surat Basin 2

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UQ-SDAAP | Sequence Stratigraphy of the Precipice Sandstone and Evergreen Formation in the Surat Basin 2 v The University of Queensland Surat Deep Aquifer Appraisal Project (UQ-SDAAP) Scoping study for material carbon abatement via carbon capture and storage Supplementary Detailed Report Sequence stratigraphy of the Precipice Sandstone and Evergreen Formation in the Surat Basin 30 April 2019 Authors Dr Andrew La Croix, The University of Queensland Mr Jiahao Wang, The University of Queensland Mr Sebastian Gonzalez, The University of Queensland Mr Jianhua He, UQ Energy Initiative Prof Jim Underschultz, The University of Queensland Prof Andrew Garnett, The University of Queensland Acknowledgements This working document was prepared for The University of Queensland Surat Deep Aquifer Appraisal Project (UQ-SDAAP), a 3-year, $5.5 million project funded by the Australian Government through the Carbon Capture and Storage Research Development and Demonstration (CCS RD&D) programme, by Coal 21, and The University of Queensland. Citation La Croix A, Wang J, Gonzalez S, He J, Underschultz J & Garnett A (2019), Sequence stratigraphy of the Precipice Sandstone and Evergreen Formation in the Surat Basin, The University of Queensland Surat Deep Aquifer Appraisal Project – Supplementary Detailed Report, The University of Queensland. Referenced throughout the UQ-SDAAP reports as La Croix et al. 2019b. Publication details Published by The University of Queensland © 2019 all rights reserved. This work is copyright. Apart from any use as permitted under the Copyright Act 1968, no part may be reproduced by any process without prior written permission from The University of Queensland. ISBN: 978-1-74272-247-4 Disclaimer The information, opinions and views expressed in this document do not necessarily represent those of The University of Queensland, the Australian Government or Coal 21. Researchers within or working with the UQ-SDAAP are bound by the same policies and procedures as other researchers within The University of Queensland, which are designed to ensure the integrity of research. The Australian Code for the Responsible Conduct of Research outlines expectations and responsibilities of researchers to further ensure UQ-SDAAP | Sequence stratigraphy of the Precipice Sandstone and Evergreen Formation in the Surat Basin 2 Contents 1. Executive summary........................................................................................................................... 5 2. Introduction ....................................................................................................................................... 6 2.1 Purpose ............................................................................................................................................... 6 2.2 Introduction .......................................................................................................................................... 6 3. Geological setting ............................................................................................................................. 6 4. Methods .............................................................................................................................................. 8 5. Sequence stratigraphic framework ................................................................................................. 9 5.1 Stratigraphic interpretation of representative wells ............................................................................. 9 5.1.1 Woleebee Creek GW4 ...................................................................................................................... 10 5.1.2 Taroom 17 ......................................................................................................................................... 12 5.1.3 Roma 8 .............................................................................................................................................. 14 5.2 Seismic stratigraphic interpretation ................................................................................................... 15 5.3 Well correlations demonstrating the stratigraphic framework ........................................................... 17 5.3.1 Well Section 1 ................................................................................................................................... 17 5.3.2 Well Section 2 ................................................................................................................................... 18 5.3.3 Well Section 3 ................................................................................................................................... 19 5.3.4 Well Section 4 ................................................................................................................................... 19 6. Discussion ....................................................................................................................................... 20 6.1 Subdivision of the Precipice Sandstone and Evergreen Formation .................................................. 20 6.2 Sequence stratigraphic model ........................................................................................................... 21 6.3 Architecture of the reservoir-seal pair ............................................................................................... 21 7. Conclusions ..................................................................................................................................... 22 8. References ....................................................................................................................................... 23 9. Appendices ...................................................................................................................................... 26 9.1 Appendix A ........................................................................................................................................ 26 Figures Figure 1 (A) Geographic location of the Eromanga, Surat, and Clarence-Moreton basins in Australia. (B) The main structural features of the Surat Basin, and the location of wells used in cross sections, including the location of cored wells discussed in this report. (C) Structure-contour map of the base-Surat unconformity surface. ................................................................................................. 7 Figure 2 Comparison of various lithostratigraphic and sequence stratigraphic schemes for the Surat Basin, displayed next to the eustatic sea level curve developed by Haq et al. 1987. The Westgrove Ironstone Member has been dated using palynology to represent a regional transgression that correlates with the early Toaracian global sea level rise (Hallam and Wignall, 1999). The Precipice Sandstone and Evergreen Formations were defined as supersequences by Hoffmann et al. 2009. ............................................................................................................... 8 Figure 3 Summary of the stratigraphic nomenclature used in the UQ-SDAAP Project. The figure shows two of the most commonly applied lithostratigraphic schemes, our newly proposed sequence stratigraphic scheme, along with identification of the corresponding seismic events. ................ 10 Figure 4 The sequence stratigraphic framework applied to Woleebee Creek GW4. See Figure 1 for well location. PEF=photoelectric factor, LLM=medium resistivity. ..................................................... 11 Figure 5 The sequence stratigraphic framework applied to Taroom 17. See Figure 1 for well location. .. 13 UQ-SDAAP | Sequence stratigraphy of the Precipice Sandstone and Evergreen Formation in the Surat Basin 3 Figure 6 The sequence stratigraphic framework applied to Roma 8. See Figure 1 for well location. ....... 14 Figure 7 (A) Synthetic seismogram from Woleebee Creek GW4. (B) An east-west trending seismic section tied to Woleebee Creek GW4 that illustrates the sequence stratigraphic framework. The seismic data and synthetic seismogram are displayed in zero phase with SEGY convention polarity. See Figure 1 for section location. .................................................................................. 16 Figure 8 East-west trending seismic section showing the Lower Jurassic sequence stratigraphic framework across the northern Surat Basin. The base of the Lower Jurassic (Seismic Event 5) is a regional unconformity typically manifest by truncation and onlap reflector terminations. Note that the reflectors between Seismic Event 4 and 5 onlap and thin toward both the western and eastern basin margins. See Figure 1 for section location. .......................................................... 16 Figure 9 East-west trending seismic section showing the Lower Jurassic sequence framework across the middle of the Surat Basin. See Figure 1 for section location. ..................................................... 17 Figure 10 SSE-NNW trending cross section (Section 1) showing the Lower Jurassic sequence stratigraphic framework. The Precipice Sandstone is significantly thinner towards the south. See Figure 1 for the location of the section and the wells with core. ................................................. 17 Figure 11 East-west trending well section (Section 2) showing the Lower Jurassic sequence stratigraphic framework. See Figure 1 for the location of the section and the wells with core. ....................... 19 Figure 12 ENE-trending well section (Section 3) showing the Lower Jurassic sequence stratigraphic framework. See Figure 1 for
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