XRD records the diffraction or reflection of a beam of X-rays by solids, including geological samples. The unique arrangement of atoms in each mineral’s crystal structure interacts with the X-ray beam, producing regions of diffraction intensity, or peaks, diagnostic for that mineral.
XRD records the diffraction or reflection of a beam of X-rays by solids, including geological samples. The unique arrangement of atoms in each mineral’s crystal structure interacts with the X-ray beam, producing regions of diffraction intensity, or peaks, diagnostic for that mineral.
The results from XRD analysis can be used in conjunction with our other mineralogy services (FTIR, SEM, and optical mineralogy) to provide an integrated understanding of the mineral content of a geologic sample. We can analyze a wide variety of solid samples from many sources, including cores, cuttings, outcrops, soils, sediments, and cements.
For advanced interpretation in our lab, we utilize JADE software for mineral identification combined with the International Centre for Diffraction Data’s (ICDD) PDF-2 Minerals Database, containing over 250,000 reference-XRD patterns. We then quantify the identified minerals with the Rietveld method using SIROQUANT software.
We provide Bulk analysis (percentages of identified mineral and total clay without speciation), Bulk+Clay analysis (percentages of identified mineral as well as different clay types), and Bulk+Clay+Kübler Index (illite) for determination of thermal maturation.
XRD Applications:
Provenance & clay diagenesis:
• Feldspar type and relative abundance
• Carbonate abundance
• Polytypes of illite/mica
• Expandability of inter-stratified illite/smectite
Well completions & pipelines:
• Recognition of pore-throat plugging derivatives of zeolite minerals and Fe-rich carbonates
• Location of siderite, pyrite, and other problematic scale-producing minerals
Petrophysics:
• Identification of producing zones in formations where chlorite suppresses resistivity
• Location of reservoir quality sands where K-feldspar content produces high gamma-ray readings similar to adjacent shales
• Improvement of porosity evaluation with formation-specific grain density
• Calculation of relative brittleness from mineralogy
XRD Instruments:
ALS has a variety of versatile XRD instruments to cover all needs:
BRUKER D4 Endeavor
• Advanced system for powder application
• High-precision 2-circle goniometer and modern X-ray optics and detectors for superior analytical results.
• Scintillation and LYNXEYETM Detectors
• High measurement speed at lowest detection limits
BRUKER D2 Phaser
• Desktop diffractometer for all X-ray powder diffraction applications in Bragg-Brentano geometry.
• High precision and reliable results
• Suitable for portable labs and well-site locations
Olympus Terra
• Rugged, ultra-portable instrument designed for field and wellsite use
• Needs only a very small sample size (less than 1 gram)
• Near-real time analysis using our proprietary Reference Intensity Ratio (RIR) method performed around the clock by ALS technicians in Houston via the internet
• Provides bulk mineralogy (quartz, feldspar, carbonates) and total clay proportion
XRD Analysis Timetables:
• Near-real time bulk sample mineral quantification at wellsite (major minerals only) with Terra units
• Around-the-clock premier “Hot Shot” XRD lab analysis for rapid, higher resolution results with Bruker instruments
• Flexibility to choose Bulk (wellsite or high-resolution lab-based) or Bulk+Clay (lab-based) quantitative XRD analysis