Geochemical and Reservoir Characterization, Reservoir Proximity and Production Efficiency; advantages of Mass Spectrometry and real-time Well Gas interpretation at the Wellsite
Our webinar will focus on case studies showing the benefits of mass spectrometry and real-time well gas interpretation
Using mass spectrometry for advanced well gas interpretation in real-time at the wellsite improves the understanding of your reservoir geochemistry and provides an additional analytical dataset to assess reservoir proximity and enhance production efficiency, that GC technology alone cannot.
In this case study, mass spectrometry was used to analyse well gases from isolated Anhydrite and Limestone horizons assumed to be non-hydrocarbon bearing, within a Halite formation overlying a lower hydrocarbon reservoir. Advanced gas interpretation was used to characterize the potential reservoir and provide an in depth understanding of these horizons and their geochemical signatures. Assessing communication between the horizons and the underlying known reservoir (figure 1) and providing additional knowledge on associated water and dynamic fractionation using Aromatic gas species only detectable in real-time through the use of mass spectrometry.
Figure 1: Isolated Anhydrite/Limestone horizons and their fluid fingerprints (red, orange, green) compared to the lower reservoir fluid fingerprint (blue, purple).
‘Ahead of bit detection’ of a hydrocarbon zone or ‘proximity to pay’ can be inferred from the use of these aromatic hydrocarbon species. Soluble in formation water they are easily transported away from reservoir formations into the surrounding sealing formations, thus allowing trends in the aromatics to be used as an early indicator for section TD, casing and coring picks (figure 2). The same principle along with fluid fingerprinting is used to geochemically aid geo-steering operations, allowing a hydrocarbon ‘sweet spot’ to be tracked through extended horizontal reservoirs (figure 2), optimizing the well path not only through zones of increased porosity and preferred inferred fluid API but steering away from hazardous zones of increased BTEX components or CO2, only detectable using mass spectrometry, that would impact on completion and production efficiency. An additional advantage of mass spectrometry is the real-time detection of ethene, a proxy for bit burn recognition. Cracking of alkane hydrocarbons occurs due to the extreme temperatures caused by a worn bit. Ethene can be measured to give early indications of bit burn, improving the knowledge for decision making around bit trips.
Figure 2: Increasing aromatics with proximity to pay and geochemically steering the well path