Exploration for oil and gas requires intense scientific investigation to identify accumulations and de-risk exploration and production. New tools are required for the investigation of petroleum system elements in the era of ultra-deep wells, unconventional oil and gas, subsalt exploration, and frontier exploration in extreme environments. Bruker’s tools for reservoir characterization and chemostratigraphy include the ability to visualize and characterize the composition of rocks at scales from the basin to the pore.
Chemostratigraphy is the use of variations in the chemical composition of sedimentary successions to:
understand correlative relationships at the basin or field scale
identify elemental proxies used in paleoecological reconstructions
aid in building sequence stratigraphic frameworks
identify physical properties of rocks for drilling and compilations
Bruker provides tools for the elemental and chemical analysis of core and cuttings to make chemostratigraphy easy and scalable. Click below to learn more about applying chemostratigraphy to any sized project.
Elemental Analysis is an important tool for the field and petroleum geologist to characterize and identify petroleum- or gas-bearing formations. Drill cuttings, mud, or cores can be analyzed by X-ray Fluorescence (XRF).
The benchtop S2 PUMA Series 2 reaches low detection limits on prepared drill cuttings in a mobile lab by using the Energy Dispersive XRF (EDXRF).
The analysis of majors and traces in the lab is best performed by the floor standing S8 TIGER Series 2 Wavelength Dispersive XRF (WDXRF) spectrometer using either the GEO-QUANT package or custom calibrations.
The CTX is a compact portable countertop XRF ideal for rig operations, with a battery backup, push-button operation, spill-proof rugged aluminum case, and safety-interlocked lid. Now available with the MUDROCK matrix-matched calibration, the versatile GeoEXPLORATION calibration, or a custom calibration.
The TRACER 5g is the ideal portable XRF for core, outcrop, or cuttings. With a helium flush and graphene window it has the best light element performance in a handheld. When paired with the MUDROCK calibration or a custom matrix-matched formation-specific calibration it is the most trusted portable XRF in oil and gas.
Additional information on the mineralogical composition of the sediment or formation is offered by X-ray Diffraction (XRD). XRD distinguishes minerals that have the same or similar chemistry by their crystal structures. It not only allows the identification of minerals with DIFFRAC.EVA, but also offers standardless quantification using the Rietveld approach. Even non-crystalline phases may be quantified using this method. It enables pinpointing of potential reservoirs and host formations. A major advantage is the rather simple and quick sample preparation. The analysis of drill cuts can be done in a mobile lab using BRUKER’s benchtop D2 PHASER. In a lab setting, the D8 ENDEAVOR or the D8 ADVANCE is the optimal choice.
Reservoir characterization models incorporate rock characteristics related to the storage and production of hydrocarbons. Bruker’s innovative rock characterization tools can provide new types of information in sedimentary rocks:
Visual geochemistry of sedimentary rocks, including visualizations of elemental and molecular distributions
Maps of minerals on scales from microns to nanometers including the ability to combine methods to translate 2D data to 3D data
Visualization and characterization of pores and permeability in two and three dimensions including nanodarcy pores in shale and complex pore networks in sandstones
Below is a summary of methods used for reservoir characterization. Reach out to Bruker’s oil and gas experts to discuss any analytical needs and to the best solution.
Understanding porosity and permeability is important for oil and gas reservoir characterization, sedimentology, hydrogeology and groundwater studies. XRM enables characterization and visualization of pores, pore size distribution, and of open versus closed pore networks. This information can have profound implications on oil and gas production models, gas or water flooding, analog studies, contaminate flow modeling, deformation experiments and sedimentary petrology.
The analysis of shale reactivity typically involves a variety of analytical techniques, including but not limited to X-ray diffraction, X-ray fluorescence, gamma logging, optical microscopy, electron microscopy, total organic content, and cation exchange capacity. From a mineralogical perspective, XRD is widely considered to be the favored technique, particularly for discrimination between elementally similar phases.
For example, hematite (Fe2O3) and siderite (FeCO3) give similar elemental signatures but distinct diffraction patterns. Diffraction data are often obtained for both vertical and horizontal segments of wellbores. Analysis of the vertical section allows for the identification of zones with desirable physical properties. In horizontal segments of unconventional reservoirs, XRD is primarily used in geosteering, to ensure that the wellbore stays within a specific geological bed.
|Method||Characterization Targets||Sample Preparation|
|Benchtop micro-XRF||Map texture, composition and sedimentary structures with major and trace elements down to 18 µm||Slightly rough to flat surfaces, standard thin sections, billets, core plugs, core slabs, cuttings scatter mounts.|
|XRM / X-ray Microscope||Three-dimensional mapping of structures and porosity||Core plugs, rock fragments|
|Raman Microscopes||Molecular structures with Raman scattering phenomenon for organic matter analysis, thermal maturity, and fluid inclusion analysis.||Standard thin sections, cuttings, core plugs.|
|FTIR Microscopes||C-H-O functional groups including organic matter analysis, mineral identification, and hydrocarbon analysis||Polished and smooth surfaces, thin sections, core, cuttings|
|EDS on Scanning Electron Microscope (SEM)||Microanalysis of pores and textures for detailed characterization major and some trace elements||Polished and coated thin section or SEM mount. Vacuum required.|
|Automated Mineralogy||Combines BSE and EDS for high-speed large-area mineral maps to characterize texture, porosity, mineral associations, calculated physical properties (young’s modulus), and generate targeting for LA-ICP-MS of zircons||Polished and coated thin section or SEM mount. Vacuum required.|
|micro-XRF for Scanning Electron Microscope (SEM)||Improve trace-element performance in a scanning electron microscope with a 100 µm X-ray spot, particularly important for environmental proxies such as U and Mo.||Polished and coated thin section or SEM mount. Vacuum required.|
|EDS on Transmission Electron Microscope (TEM)||Major elements and some trace elements with the best resolution.||Specialized TEM lamina sample preparation.|
|Nano-indentation||Benchtop or SEM-mounted hardness testing used to calculate Young’s modulus and other physical parameters||Polished and coated thin section or SEM mount. Vacuum sometimes required.|
|Atomic Force Microscopy||An emerging tool for surface characterization at near-atomic scales may be used for identification and characterization of solid organic matter||Polished thin section or mount, vacuum not required|
|EBSD/TKD||Detailed mineral maps and crystal orientation studies.||Highly polished thin section and electron transparent samples|
||Crystallographic phase identification and quantification||Ground powders and flat surfaces|