Biostratigraphic services primarily include the study of foraminifera, calcareous nannoplankton, palynology, and conodonts. Other less commonly used microfossils such as radiolarians, diatom, and ostracodes may also be included.
Foraminifera results provide age and bathymetric records of marine sediments in the basin. Calcareous nannofossils when analyzed with foraminifera can give a more detailed bracket of age determination and also confirms the marine environment for the samples. Palynology is useful for non-marine, lacustrine, and near-shore sediments. It can also be used when the samples are from the Paleozoic Era, since nannofossil and planktic foraminifera are not found in those sediments, although palynology is useful throughout the geologic eras, from Precambrian to Recent.
Samples are submitted for current chemical or physical processing methods to release the microfossils. For palynological and foraminiferal processing, 40 grams are used, while 5 grams are used for nannofossil processing.
The species are recorded in a spreadsheet that can be used for correlation with future wells from the same geographic area. Stratabugs software is used to incorporate multi-disciplinary recovery of all the microfossils from the sample, with their occurrence frequency plotted against sample depths. The interpreted depositional environment and age determination, and any wireline logs, are also assembled into the results.
We can provide biostratigraphic analysis for samples of any geological age. The best lithologies for sample recovery are mudrock, shale, and limestone. Uniform sampling intervals of 30 ft (10 m) from a well is most ideal.
All our biostratigraphers are highly experienced with over 25 years in the oil industry or academia. Their geographic expertise also encompass many areas in North and South America, Europe, Asia, Africa, and Australia. A detailed biostratigraphic report and recovered microfossil species range chart will be provided, which may be customized to the client's needs.
Benefits of biostratigraphic analysis include:
Complete species lists
A written biostratigraphic report with the age interpretation, along with key diagnostic microfossil species
A plot of recovered microfossil species versus sample depth detailing the interpreted age and correlation point (plot will include gamma log if it is provided by the client)
Projects with foraminiferal analysis will be provided with interpretations of flooding surfaces based on the recovery of the foraminiferal species