ALS offer the manufacture of high quality thin sections routinely prepared from cuttings, core chips, sidewall cores or conventional core analysis plugs. Large glass slides are used to mount larger core samples or SCAL plug trims.
Samples are initially vacuum-impregnated with blue-dyed epoxy resin to assist in stabilising the material and in the identification of porosity. A combined Alizarin Red S/potassium ferricyanide stain can be applied in order to distinguish calcite from dolomite cements and to recognize ferroan carbonate varieties. A sodium cobaltinitrite stain may be used to stain and identify K-feldspar grains.
In addition to naturally occurring rocks, thin sections of construction, ornamental and archaeological materials can also be provided. ALS also provides teaching sessions on the thin section preparation process.
Nannofossil Slide Preparation:
ALS offers smear slide preparation for calcareous nannofossil analysis, both at the laboratory and wellsite, using established methodology that allows for identification of individual species that aid in biosteering. A representative portion is taken from the sample and used to create a slurry that is then placed on a glass side and dried, then covered with a cover slip. Smear slides can be made from cuttings, dried washed samples or cores.
Microfossil Sample Preparation:
ALS prepares washed residues, both at the laboratory and wellsite. Samples are treated by removing drilling mud and then soaked to allow for disaggregation. The sediment is then washed over predetermined sieve sizes, based on client preference or sample need, and then dried and transferred to envelopes. This residue can then be used for microfossil paleontological analysis, including foraminifera and radiolaria that can be used for biosteering and/or palaeoenvironmental interpretations.
Additional processing for indurated rock is available through the acetic acid technique. This technique, conducted by in-house experts, allows for the retrieval of microfossils in samples that previously may not have been able to be analysed due to inability to recover the fossils.
Thin Sections Specifications:
• Sample: outcrop, cuttings, core chips, core plugs, sidewall cores, consolidated and unconsolidated
• Size: Standard slide 3”x1” or 2”x 1” European (45 x 30mm), 3”x 1.5” or 3”x2”
• Impregnation: clear, blue- or fluorescent-dyed epoxy resin
• Staining: carbonates and/or feldspar (upon request)
• Glass coverslip or polished.
Mobile Thin Section Laboratory:
At the wellsite, ALS can deploy a Mobile Thin Section laboratory, for rapid thin section creation. The application has been used throughout the Middle East and North Africa.
• Mobile Laboratory can be set up on- or off-shore
• Polishing tables, Epoxy impregnation equipment, Microscopes…
• Additional analytical tools (particle size analysis, X-Ray Diffraction, etc.) available
• Allow near-real time petrographic and biostratigraphic analyses for bio-steering applications