The Fluid Inclusion Stratigraphy (FIS) analysis technique from SLB has become a widely used geochemical tool used in petroleum exploration t0 analyse the composition of trapped fluids within rock samples to better constrain fluid migration, reservoir compartmentalisation, and petroleum charge history. The technique analyses volatile compounds within fluid inclusions (tiny pockets of liquid or gas trapped in minerals) to help to predict oil and gas distribution, characterize undiscovered petroleum, and assess exploration potential.
Bulk fluid inclusion volatiles are instantaneously released from each sample in a sequential manner by automated mechanical crushing. Volatile organic and inorganic species are dynamically pumped through quadrupole mass analysers where they are ionised, separated according to their mass/charge ratio and recorded, with data presented as individual tracks for each analysed component across the sampled depth range. Typically hundreds of rock samples from an individual well are analysed for each sampled well.
The composition and abundance of the volatile components are assessed, including both inorganic and organic compounds with up to 13 carbon atoms. Essentially analysing the gasoline range fraction of the petroleum fluids the technique provides a response that is compared against a standard to deliver a relative response.
FIS analysis is a rapid and cost effective tool that is typically used to screen large numbers of samples across the length of the sampled section within the well being analysed. It is commonly applied as a post-mortem analysis to better understand reasons for failure in dry exploration wells where conventional oil and gas shows are lacking or are not diagnostic due to mud contamination or the use of petroleum based drilling fluids.
FIS generates a large amount of geochemical data that requires careful interpretation to produce useful outcomes. The relative variation in responses across the sampled section is evaluated to allow zones with increased hydrocarbon intensity to be recognised as well as interpreting the variations in water-soluble compounds that can be used to potential proximity to nearby hydrocarbon accumulations.
Limited data has been published to show how reliable these interpretations are when inter-well comparisons are considered or results from wells with different charge histories are looked at collectively, both within basins and between basins. Recognising a level of signal that is significant and can be differentiated from background noise can lead to subjective interpretations that are prone to error. Similarly understanding the repeatability of the measurements is critical to enable confident interpretation.
Fluid inclusion techniques have been widely used in Australia for more than 30 years to address petroleum systems issues. Across the broader APAC region more than 1000 wells have fluid inclusion data, with much of it now available in the public domain thanks to data release obligations. Ascendience Geoscience had compiled these data into a comprehensive online database to assist future use of these important datasets. The compilation includes FIS data from over 300 wells, 180 of which have digital data available in .las file format.
Whilst the data contained in the large database has direct application to constraining petroleum systems risks in sedimentary basins across the APAC region, there is also great potential to use this resource to aid the interpretation of FIS data acquired in other parts of the world. As perhaps the largest public domain database of this type in the world and comprising wells from different basins, lithologies, tectonic settings and reservoir types the collective data has great value for constraining new datasets that you acquire. Applications include improved understanding of significant signal response compared with levels associated with background noise, more comprehensive understanding of charge access, hydrocarbon fill history, recognition of potential bypassed pay and importance of proximity to pay responses. Improved appreciation of the applications to seal evaluation, secondary alteration by biodegradation or water-washing and the emerging applications to new energy projects like geological storage of CO2 or implications for natural hydrogen exploration.
If you are a regular user of the FIS method looking to strengthen your data interpretation confidence or a new user looking to better understand the value that can be created from this type of data then Contact us for more information on how our Cyclops database can contribute to more successful application of this tool.
Ascendience Geoscience offers two pathways for organisations to access the learnings from this comprehensive database:
- We can provide the FIS calibration database as an off the shelf product that contains digital data within a web-maps GIS front end, allowing it to be readily incorporated into you existing database structure. Access to the full database is available for US$5000.00 providing cost-effective method to constrain the results of your own FIS data.
- Alternatively, we are currently scoping a more comprehensive study to fully assess the application of these data to address common oil and gas related questions. Project Veritas will be a multi-client study designed to shed more light on the applications and limitations of FIS datasets to common E&P issues. Key aims would be to investigate the characteristic responses seen in wells with different charge histories including oil and gas discoveries, breached traps and dry holes, to evaluate the influence of variables like depth, temperature, lithology, and structural setting, and to test the reproducibility of the data using examples where FIS analysis has been undertaken on the same wells multiple times for different operators.
We have deep experience in the planning new fluid inclusion studies and choosing the best methodologies to address a wide range of common exploration and development problems. We can assist with interpretation of all types of fluid inclusion data in different geological settings and effectively integrate results within a petroleum systems framework.
A flyer for the FIS Calibration database can be found HERE
A flyer for Project Veritas can be found HERE
