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Multispectral and Surface Sampling approach to Gold Exploration in Marble Bar, Australia Kevin D. Box Advisor: Dr. Jay Parish GEOG 596A Second Spring Semester.

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Presentation on theme: "Multispectral and Surface Sampling approach to Gold Exploration in Marble Bar, Australia Kevin D. Box Advisor: Dr. Jay Parish GEOG 596A Second Spring Semester."— Presentation transcript:

1 Multispectral and Surface Sampling approach to Gold Exploration in Marble Bar, Australia Kevin D. Box Advisor: Dr. Jay Parish GEOG 596A Second Spring Semester

2 General Outline Project Objective Background – Criteria for economic success – Deposit Type – Deposit Deposition – Area of interest Methodology – Data – Work flow – Ratios Potential Exploration Targets Moving Forward

3 Project Objective Utilize remote sensing techniques to identify potential gold bearing conglomerates within the Marble Bar Basin. Actively explore targets, identified from remote sensing, using field work and surface sampling to validate success and failures of remote sensing in exploration.

4 Economic Gold Deposits – Grade Must be high enough to warrant mining – Tons Must have enough gold to warrant mining – Geometry Deposit must be large enough to warrant cost of mill and extraction methods – Depth With excessive depth comes excessive waste and cost The four combined factors create a formula that is the primary criteria for whether a deposit can economically be mined at a profit. Many deposits do not meet these criteria to be economically profitable. Background

5 Disseminated – Very fine grained gold dispersed through the rocks. Large deposits and usually low grade but still economically feasible. Carlin, Nevada Cripple Creek, Colorado Homestake, South Dakota Vein (Lode) – High grade concentration as a result of hydrothermal solutions being forced through faults or fractures. Very high concentrations within a tight space. Sleeper, Nevada Mother Lode, California Gold Deposits

6 Placer – Gold deposition as a result of weathering and being moved by water. These are usually formed with alluvial and beach systems. California Gold Rush Klondike, Canada Nome, Alaska Paleoplacer – “Old” placers. Old placers that have been fossilized into rock. Deposited in a sheet and can be kilometers long. Gold can be disseminated and crystalline. Witwatersrand, South Africa – 1.5 billion ounces – Over 4km deep Gold Deposits

7 Multiple Theories – – Placer Model Occurred during orogenic formation – Hydrothermal Model Sediments were deposited and fluids were hydrothermally pumped into the sediment seams then compressed to reform as rock – Microbial Model BUGS! – Gold concentrations in seawater during the time of deposition could have ranged from 4 – 40 ppb (compared to today of 4ppt) – Microbes play a role in exhaling gold from seawater and creating pyrite in the process. Also could explain the formation of the high grade carbon leaders in the Witwatersrand deposit Paleoplacer Gold Origin

8 Basin Sediment Deposition Trapped Sediments Sediments Reworked in Streams Shoreline Sediment Deposition The three theories agree that paleoplacers are sediment deposited.

9 Sediment deposition Basement Rocks Sediment Package Volcanic Cover Gold Bearing Conglomerate(s) Examples of Gold Bearing Quartz Pebble Conglomerate from diamond drilling at Nullagine, WA

10 Pilbara Exploration Multiple basins identified in remote regions of Western Australia that contain potential economic sediment hosted paleoplacer gold systems similar to Witwatersrand, South Africa Nullagine – resource of 421k oz. inferred gold defined in 2012 from initial drilling by Novo Resources Corp. in gold bearing conglomerates Novo Resources Corp. exploration identified a gold bearing conglomerate on the opposite side of the basin over 1km long with grades in excess of 10 gpt up to 50 gpt at surface. Why Australia? Nullagine Basin Marble Bar Basin

11 Historical Mining 65 km 50 km © Harris Corp, Earthstar Geographics LLC © 2013 Microsoft Corporation Marble Bar Basin Question: Does the Marble Bar Basin hold the same potential as seen at Nullagine in 2012? Over 175,000hectares (436,000 acres) of land to explore. Historical mines (alluvial and hard rock) in in the late 1930’s and early 1940’s on the south east flank of basin —Tassie Queen —Just in Time —Comet Sporadic ground work within interior and flanks shows that favorable conditions exist from stream sediment samples in areas of easy access.

12 Historical Mining 65 km 50 km © Harris Corp, Earthstar Geographics LLC © 2013 Microsoft Corporation Marble Bar Basin Complications Over 175,000hectares (436,000 acres) of land to explore. Much of the land is only accessible via helicopter, ATV or foot resulting in inadequate modern exploration. Sporadic ground work has been limited to easy access areas. Very little is known about the vast majority of the basin. Work in this region is expensive for lodging, food, and salaries

13 Area covered in volcanic basalt with sediment lenses that have the potential to host gold Marble Bar Basin is part of the Fortescue Group consisting primarily of Archean rocks with little overlying Tertiary rocks Basement Rocks Sediment Package Volcanic Cover 1:100k geology map from GSWA (Geological Survey of Western Australia) Marble Bar Geology

14 Characteristics of the target conglomerates Quartz pebbles and boulders Matrix is a mixture of silica with clays such as sericite, illite, and smectite —Note: matrix mixture includes kaolinite. However, kaolinite is a common clay remobilized from weathering elements such as wind and water Low mafic content Low epidote, chlorite, and amphibole Low carbonates

15 Remote Sensing Why choose remote sensing? Proven successful in identifying certain rock types where rocks are exposed —Marble Bar sits in barren dry climate ideal for remote sensing Inexpensive when using ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) multispectral data —Covers large areas – single tile 60 km² —Contains 14 bands that cover VNIR (Visable Near Infrared), SWIR (Shortwave Infrared) and TIR (Thermal Infrared) spectral ranges. —Spectral bands of SWIR and TIR are useful in identifying clays and silica material —Bands can be combined into ratios based on certain mineral signatures

16 ASTER Spectral Ratios and Minerals Key spectral signatures of the Marble Bar Basin SWIR – 6 bands (channels) —Carbonates, Clay, and Mafic TIR – 5 bands (channels) —Carbonates, Mafic, and Silica/Quartz

17 ASTER Spectral Ratios and Minerals Spectral Example – Quartz – SiO2 Quartz Rich Rock – B14/B12 (Kalinowski, A., & Oliver, S., 2004 ) Silica Rich Rock – B13/B10 (Kalinowski, A., & Oliver, S., 2004) TIR Band 10 TIR Band 11 TIR Band 12 TIR Band 13 TIR Band 14

18 Issues with ASTER Broad paint brush complicates supervised classification and choosing regions of interest (ROI) —30m pixel resolution in SWIR —90m pixel resolution in TIR Line striping or smearing of image —Most common in TIR bands Mineral spectrums can overlap and cause misidentification —Spectral profile comparisons are complicated Poor imagery —Cloud cover —Fire within imagery

19 Aster Imagery Workflow Identify Area of Interest Acquire Imagery Layer Stack TilesMosaic Tiles Create Individual Ratios Band Math Unsupervised Classification Analyze Results Re-work Ratios Review Ratio Results ExperimentPhase Map Results Plan Exploration Program Software Used ENVI – ASTER Processing ArcGIS - Mapping

20 Aster Ratios – Quartz Rich Rock Ratio = b14/b12 (Kalinowski, A., & Oliver, S., 2004) Highlights areas with quartz rich rocks. This can include sandstones, quartz pebble conglomerates, veins, etc. ©METI and NASA 2001 © Harris Corp, Earthstar Geographics LLC © 2013 Microsoft Corporation

21 Aster Ratios – Silica Ratio = B13/B10 (Kalinowski, A., & Oliver, S., 2004) Highlights areas with silica rich rocks and sands. This can include crystalline silica found in the matrix of sandstones, quartz pebble conglomerates, veins, etc. ©METI and NASA 2001 © Harris Corp, Earthstar Geographics LLC © 2013 Microsoft Corporation

22 Aster Ratios – Sericite, Muscovite, Illite, and Smectite Ratio = (b5+b7)/b6 (Kalinowski, A., & Oliver, S., 2004) Highlights clays or soils rich in sericite, muscovite, illite, or smectite. **Burn areas show in SWIR bands. When analyzing you must be aware of this. ©METI and NASA 2001 Burn Area © Harris Corp, Earthstar Geographics LLC © 2013 Microsoft Corporation

23 Aster Ratios – Mafic Rocks Ratio = b12/b13 (Kalinowski, A., & Oliver, S., 2004) Highlights mafic rocks such as basalt, dolerite, and gabbro. These are all extrusive or intrusive igneous rocks. ©METI and NASA 2001 © Harris Corp, Earthstar Geographics LLC © 2013 Microsoft Corporation

24 Aster Ratios – Epidote, Chlorite, and Amphibole Ratio = (b6+b9)/(b7+b8) Highlights areas with minerals that are associated with igneous rocks at Marble Bar. ©METI and NASA 2001 © Harris Corp, Earthstar Geographics LLC © 2013 Microsoft Corporation

25 Aster Ratios – Carbonates Ratio = B13/B14 Areas that have a high carbonate signature. Most likely remobilized calcite or calcrete. ©METI and NASA 2001 © Harris Corp, Earthstar Geographics LLC © 2013 Microsoft Corporation

26 Aster Ratios – Final Results Band Math = (R1+R2+R3)- (R4+R5+R6) R1-Quartz Rich Rock R2- Silica R3 – Sericite, Muscovite, Illite, and Smectite R4 – Mafic Rocks R5 – Epidote, Chlorite, and Amphibole R6- Carbonates Highlights show potential Au bearing rocks worthy of follow ups. ©METI and NASA 2001 © Harris Corp, Earthstar Geographics LLC © 2013 Microsoft Corporation

27 Aster Ratios – Final Results with Historic Stream Sediment Data Historic stream sediment samples collected by multiple parties from 2005 through – Positives Anomalous grades or better confirm areas for potential conglomerates – Issues: Sampling methods unknown Stream sediment data not distributed evenly Currently do not have elevation data to perform adequate stream flow analysis ©METI and NASA 2001 © Harris Corp, Earthstar Geographics LLC © 2013 Microsoft Corporation

28 Aster Ratios – Final Results with Stream Sediment Data and Geology Geology conforms closely with results Three distinct areas that are part of the Hardy Sandstone unit have different signatures. ©METI and NASA 2001 © Harris Corp, Earthstar Geographics LLC © 2013 Microsoft Corporation

29 Aster Ratios - Targets Areas Identified from Aster data that show potential conglomerates – Numerous areas are showing linear type features that could be exposed conglomerates – Most importantly ASTER is telling us where not to go © Harris Corp, Earthstar Geographics LLC © 2013 Microsoft Corporation ©METI and NASA 2001

30 Additional Items or Work Acquire DEM better than 30m resolution – Stream flow analysis to get a better understanding of the sources for the stream sediment samples Continue to work with ASTER data throughout project – Ground work will reveal better information on modifying ASTER ratios Acquire aerial multispectral data for additional analysis – Collect training sites during field work – Better resolution allowing for detailed spectral signature work

31 Time Line of Project October Present results of field work at Geological Society of America Annual Meeting, Denver Colorado Mid July – August Surface samples return Evaluate results of remote sensing work Plan Drill Program Mid May – July Field workASTER changes and refinements Late April - Early May Met with team and began field planningClass presentation March – April Acquired ImageryResearch Subjects Analyzed Data February Refined Project proposal January Project proposal

32 Acknowledgements Dr. Jay Parish – Penn State Advisor Dr. Quinton Hennigh Novo Resources Corp. – Funding and use of data

33 References The ASTER L1B data was purchased through the online Data Pool at the Earth Remote Sensing Data Analysis Center (ERSDAC), (https://ims.aster.ersdac.jspacesystems.or.jp/ims/html/MaiMenu/MainMenu.html).https://ims.aster.ersdac.jspacesystems.or.jp/ims/html/MaiMenu/MainMenu.html Department of Resources, Energy, and Tourism. (2013) Aster Spectral Bands. Retrieved 29 April 2013 from ASTER - Advanced Spaceborne Thermal Emission and Reflection Radiometer and-sensors/aster-radiometer.htmlhttp://www.ga.gov.au/earth-observation/satellites- and-sensors/aster-radiometer.html Hennigh, Dr. Quinton. (2013, April 30). Personal Interview Regarding Paleoplacer Deposits and the Witswatersrand Deposit. (K. Box, Interviewer) Kalinowski, A., & Oliver, S. (2004, October). ASTER Mineral Index Processing Manual. Retrieved February 26, 2013, from Australian Government Geoscience Australia: Rajesh, H. M. (2004, June 28). Application of remote sensing and GIS in mineral resource mapping - An overview. Retrieved February 26, 2013, from J-STAGE - Japan Science and Technology Information Aggregator, Electronic: https://www.jstage.jst.go.jp/article/jmps/99/3/99_3_83/_pdf https://www.jstage.jst.go.jp/article/jmps/99/3/99_3_83/_pdf van der Meer, F. D., van der Werff, H. M., van Ruitenbeek, F. J., Hecker, C. A., Bakker, W. H., Noomen, M. F., et al. (2011, August 10). Multi- and Hyperspectral geologic remote sensing: A review. Retrieved March 27, 2013, from University of OULU Dashboard: https://wiki.oulu.fi/download/attachments/ /van-der-Meer-et-al IJAEOG.pdf?version=1&modificationDate= https://wiki.oulu.fi/download/attachments/ /van-der-Meer-et-al IJAEOG.pdf?version=1&modificationDate= Agar, B. (n.d.). ASTER Alteration and Mineral Mapping; Las Pampas, Cajamarca, Peru. Retrieved February 26, 2013, from ASTER Altera:

34 Questions?


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