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An Introduction to Portable XRF for Exploration, Mining and Geochemistry Applications. Scott Curry & Cindy Collins Innov-X Canada. Presentation Outline. Fundamental XRF Concepts and Sample Data Limitations of Portable XRF Xplorer - Seamless XRF/GPS/GIS Integration Sample Applications
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An Introduction to Portable XRF for Exploration, Mining and Geochemistry Applications Scott Curry & Cindy Collins Innov-X Canada
Presentation Outline • Fundamental XRF Concepts and Sample Data • Limitations of Portable XRF • Xplorer - Seamless XRF/GPS/GIS Integration • Sample Applications • Sampling, Project Planning and Tips for XRF • Questions
What can XRF do for reclamation? • Tailings • Chemical disposal • Soil and water contaminant analysis for mine site and perimeter monitoring • Provide large inexpensive datasets continuously from environmental baseline data to clean up and monitoring • Be an integral part of the mine reclamation plan • Be part of the tool chest of technologies and methodologies for reclamation during and after life of mine from removal of structures (Pb paint testing & metals recycling) to analyzing tailings and waste rock disposal (hydrological and soil testing)
What does XRF do? • Portable XRF can quickly and effectively Detect and Quantify the elements from Mg to U on the periodic table. • Non destructive – can test the same sample multiple times. • Fast – data can be achieved in seconds resulting in large and inexpensive data sets. • Portable – get results at the actual sample location • Accurate - Can develop semi-quantitative to quantitative data sets.
History of XRF • From the discovery of x-rays in 1895 to the quantification of x-rays in 1913 and the development of early XRF Spectrometers in the 50’s, XRF research and development continued has become what it is today • Early spectrometers were WDXRD measuring wavelength for one element at a time • With the need for smaller sized equipment, lower costs, and use by less skilled operators came the EDXRF in the 60’s; EDXRF measures the characteristic energy of an element • Subsequent improvement in detectors and signal resolution lead to measurement of several elements in one sample • Early EDXRF use radioisotopes for excitation requiring recycling of a depleted radioactive source, recalibration and replacement at significant costs • Current state-of-the-art EDXRF includes x-ray tubes, solid-state components, electronics, computers and software • Now this mature technology is routinely used for R&D, QC, production support and regulatory compliance
EDXRF Spectral Capture Example of export format (csv file)
General Environmental Applications • Mine reclamation • Environmental baseline data over large areas with large inexpensive datasets • Liquid analysis • Pb paint analysis • Filter analysis • Soil and other materials
Pb in soils • Blacksmith Institute working to limit Pb poisoning plaguing remote villages in Nigeria • In seconds the XRF analyzer identifies pollutant metals including Pb as low as 0.001% • Remediation begins and processing procedures are altered to avoid a recurrence
Hazardous Waste Screening • Debris for hazardous or non-hazardous disposal in lieu of TCLP testing (toxicity characteristic leaching) • Extreme weather debris migration • Construction or demolition project waste • Waste streams and oil pools • Industrial and mining process on community perimeters
Property Assessment • Immediately identify heavy metals in soil at low ppm levels • Real-time metal screening at construction or disposal sites – Pb, U, RCRA, Priority Pollutants • Brownfields Phase I/II/III • Lead (Pb) clearance failure avoidance • Tube-based Pb Paint Analysis • Airborne metals in mining, welding, construction, fabrication, maintenance and repair, paint removal and renovation
Published SOP Methods • EPA 6200 • XRF soil testing • HUD PCS for testing Pb in Paint • NIOSH Method for Pb in filters • OSHA Method ID204 • Quantitative X-Ray Fluorescence Analysis of Workplace Substances ID204. (Air or wipe filter & bulk material) • RWM-DR-025 • Metals in solid media
Peer Reviewed Tech Articles • Arsenic in Hurricane Katrina Wood Debris • Determination of Br in Regulated Foods • Determination of Soil Calcium Using FPXRF • Evaluation of New XRF Instrumentation at Hazmat and Abandoned Mine Land Site – Hazardous Materials • Evaluation of Portable XRF for Gypsum Quantification in Soils • Evaluation of Technologies for Sorting CCA-Treated Wood • Identification and mapping of heavy metal pollution in soils • Identification through XRF of Dental Restorative Resins • Presence and Breakdown of BFRs in Vehicles • Reclaiming Military Bases from Tungsten Takeover • Triad Case Study: Former Small Arms Training Range
CCA – Identify Toxin-Treated wood products • Screen recycled wood mulch, pellets & other by-products for toxic metals • EPA compliance & label confirmation at wood treaters, lumberyards, retail centers • Screen in-coming wood at municipal incinerators, landfills & recycling facilities • Determine effectiveness of protective coatings & sealants from CCA & other toxins • Test for arsenic leaching out of unlined landfills & around residential wood structures
Lead Inspection • Lead Inspection :Classify definitive positive/negative results for Pb in seconds • Comply with restrictions on lead exposure during building demolition & construction • Use in manufacturing, homes or commercial buildings
Innov-X System Environmental Analyzers • A Field-Proven, X-ray Tube-Based System: No Radioactive Isotopes! • Accurate Analysis of RCRA (Resource Conservation & Recovery Act) Metals & Priority Pollutant Metals in Seconds • Meets OSHA Methods OSA1 & OSS1 and EPA Method 6200 and NIOSH Method 7702! • In-situ Tests: Rapid, thorough site investigations, delineation and contamination patterns • Confirm the minimally required samples to drive investigation • Avoid confirmatory lab testing of high-concentration samples • Establish area contamination boundaries and depth profiles • Dock into convenient testing stand for bagged or liquid samples • Test directly thorough corings for depth profiles
XRF Sampling and Planning • Clearly establish project & sampling objectives • Determine the level of data quality required by XRF: field • screening or lab quality? Is it FIT FOR PURPOSE? • Establish an appropriate procedure (test times, number of • tests etc.) • Correct & Appropriated Use of Calculation Modes (CN & FP) • Always keep good records of Field Work • Incorporate QA/QC Protocols: Test relevant Matrix Matched Standards, Blanks & Field Duplicates • Dispatch a proportion of samples for confirmatory analysis: • min 5% up to 20% for checking calibrations
XRF Sampling – Tips in the field • Decide on sample spacing/density prior to heading into field – • Regular Grid? Staggered Grid? How does my grid fit the existing geology, background and the project? • Grid Systems & Projections– Lat/Long WGS84? Or Local Grid? • Be Prepared: • Do not forget Standardization Materials • Pack extra batteries & Windows (Kapton or PP?) + Screwdriver to remove Window Assembly • Include a soft lens cloth for cleaning the Window – always good to check the window after every analysis to remove contamination & inspect for damage/holes • Carry necessary standards / blanks
The surficial geology (regolith) is extremely variable dependant on environment, underlying rock type and contamination sources (mining, farming, manufacturing) Important to ensure consistent approach to sampling horizons – sample the same horizon(s) at each location Common to sample several horizons at one sample location ie. Soil A, Soil B, Saprolite, Bedrock or Cap-rocks…etc. Documentation is Integral! – Store these observations with Chemistry to enable later correlation. Make sure you are comparing apples with apples when analyzing data! Which Horizon?
Sampling Considerations • Remember, typical sample size is around 1cm2 – Collimated X-RAY Beam usually <3mm in Width • Depth of Penetration is generally limited to the surface of most samples – up to 2-5mm in very light Matrix samples • Need to get the detector as close to samples as possible – Built In safety Feature for “Air Shots” (based on lack of count rates received back) • Use Matrix specific calibrations for specific sites and known areas of matrix variation
Sample Preparation 5 mm Mg Andesite (In Situ) • Preparing your sample can significantly enhance the result quality: • Crushing /milling / pulverizing of the sample for smaller particle sizes, sample uniformity & increased homogeneity • Take advantage of new portable & mobile field preparation devices – such as Rocklabs / Essa portable Crushers & Mills • Potential to setup Miniaturized / Containerized sample prep facilities in the Field to support XRF Sampling programmes • For less homogenous samples – multiple readings & averaging can be effective • Dry the sample to take away moisture effects Soil Sample Sieved to 250 micron 5 mm
Problem Samples do exist – ie: Oxidized surfaces, very light matrices, very dense matrices…etc. Variations due to Sample Type & Homogeneity – ie: Fine Dust vs Chips vs Core vs in-situ Rock. Vertical Segregation / Stratification of sample into bags & speared samples splits. Other effects do exist and can be corrected for if known, such as moisture & attenuation through plastic/calico bags…etc. Ensure the instrument has the correct elements configured (are they turned on?) and correctly calibrated. DO NOT simply attempt to turn an element on! Addressing Issues
Factors can adjust for matrix effects - Use LAB data to verify chemistry and correct via the User Factor set Can also use Matrix Matched certified standards to correct factors if the matrix is consistent Chemistry results are only from what the X Rays see. Beware of homogeneity and surface effects. Longer Tests = better precision within limits Key Points to Remember
How can I add value to my XRF Data? XRF Sampling is NO Different to any other sampling regime you adopt!... Remember the Data is very valuable (& costly)! So, Use good QA/QC Protocols & Data Validation Incorporate Standards, Blanks, Field Duplicates and Check Samples to increase your understanding & confidence Rank & Store the Data in a well ordered & structured DB Adding Value to XRF Data
David Pawliuk, Vice President, Exploration, SILVER QUEST RESOURCES LTD., Vancouver, BC “We acquired an Innov-X Omega XRF unit early in the 2010 field season. The unit went to Yukon, where it was used to test soils in the Dawson Range for the pathfinder elements (As, Sb) associated with gold mineralization. By using the Omega our crew could immediately identify and follow-up on mineralized trends exposed in our backhoe trenches. The trenching was more efficient and focused than it otherwise would have been, saving precious time and thousands of dollars. The Omega may have paid for itself already.” Introducing the handheld
New Delta Handheld XRF • Launched globally Feb 1, 2010 as superior XRF platform to Alpha and Omega systems. • 4Watt System = most powerful Hand Held XRF on the market. • Large Area SDD = highest count rate and lowest signal to noise ratio on the market. Light element measurement capability in air (Mg, Al, Si). • Design Brief • Smaller / Faster / Cooler / Tougher • Upgradeable • Tube anode optimization (Ag, Au, Ta, Rh) • Capable of incorporating a camera and collimator for targeting smaller (<1cm2) analysis areas on samples (grain size issues) • Leap frogs existing technology in as many ways as possible • Add innovations as appropriate and make expandable and adaptable.
Delta Handheld XRF Product Models • Premium Vacuum (for low level Mg) • Large Area SDD and vacuum. • Premium • Large Area SDD detector • Standard • Typical SDD Detector • Classic • PIN diode detector • Range of tube anode materials available SDD = New Silicon Drift Detector Technology PIN = Older Silicon PIN Detector – as used in Alpha
Portable Test Stand for the Omega and Delta Allows use of the Handheld like a bench top to obtain maximum flexibility, in field or fixed in camp or lab Can be operated from laptop computer Portable Test Stand for Handhelds Lid Closed Lid Open
Dr. Trevor MacHattie, Mineral Deposits Geologist, NOVA SCOTIA DEPT. of NATURAL RESOURCES “The X-5000 produces rapid, amazingly accurate, and precise geochemical data for us. We’ve recently discovered new rare earth element mineralization with the aid of the X-5000 and it has now become an essential tool in our field work and mineral deposit research, every geologist should have one!” Introducing the original portable bench topX5000
New X-5000 Portable Bench Top • 10 Watt System = most powerful portable XRF on the market. • SDD detector = Lowest LOD’s achievable. Light element measurement capability in air (Mg, Al, Si). Better lower limits of detection than Hand Held for some elements (Au, Sb, Sn, Cd, Rare Earths) • Range of tube anode materials available for optimization for application. • Ideal for basing in an exploration camp, sample prep facility or lab where samples are collected and brought back to a central location for sample preparation and analysis. • Ideal as a back-up system to lab based equipment and online/on-stream systems. • No operator licence required in Canada. • Completely portable with battery pack.
New X-5000 for Oils, Fuels & Liquids • Transportation • Power Generation • Petrochemical • Aerospace • Mining • Rapid on-the-spot elemental analysis for oils, fuels and other liquids • Unique fluid handling system • Uses 50 KeV tube, 10 Watt power rating
Delta Xplorer SystemSeamless XRF/GPS/GIS/ Geochemical Analysis Integration Ross Sherlock Exploration Manager, Gold Fields Canada, “We have used the Omega XRF fairly extensively in our Canadian exploration efforts and are pleased with the results. In the right environment the tool provides fast and reliable geochemical information reducing lab costs and turn-around time.”
Delta Xplorer System A Total Field Data Collection Solution Consisting Of: • Ruggedized Innov-X Systems Delta Portable XRF Analyzer • Ruggedized TRIMBLE NOMAD or YUMA Field Computer with built in GPS +/- Optional High Accuracy DGPS • ESRI ArcPAD orENCOM Discover Mobile – Field Mobile GIS Integration Package • Mobile GIS extension software – Bluetooth communication software between Delta XRF, Trimble GPS and GIS software. The Essential Mobile GIS Solution for Real-Time FPXRF
In-field example: Tritton Cu NSW Sample Chemistry Registered Real-Time Nominal 50m x 50m Sample Grid Designed Actual Sample Location Taken By DGPS
Xplorer - Simplified Workflow: Innov-X Delta & TRIMBLE Nomad are Bluetooth paired for Communications Mobile GIS started on Trimble Nomad Soil Readings taken outside in open air & Result Received on Nomad GPS Position Confirmed on finalization of result Data is exported from Trimble Nomad to Mapinfo or ArcPad to ioGAS Data presented graphically in Parent GIS Xplorer Workflow
Delta Xplorer - Output WGS84 Locations Full Chemistry from FPXRF Google Earth Export From ioGAS