Blog Archive

Monday, August 10, 2026

Two AI-Assisted Subsurface Analysis Case Studies: Identifying Missed Prospects in a World Class Play and Bypassed Water-Flooded Oil in Mature Fields

    

     In both of these case studies, the goal is to recover oil or oil accumulations that have been missed by past explorers. Well-trained AI models can do that very well with better pattern recognition than humans, according to the case studies. However, in both cases, verification has not yet occurred, but bypassed oil and bypassed prospective oil accumulations have been identified. Thus, they are basically leads at this point. 

     If successful, these cases will verify that AI’s pattern recognition powers can add oil & gas reserves, in some cases, better than geologists.

 

Case Study #1 – Four Bypassed Prospects Identified in ExxonMobil’s Stabroek Block Offshore Guyana

     In May 2026, ExxonMobil Vice President of Exploration John Ardill noted that the company was expanding its use of deep learning, machine learning, and high-performance computing to analyze seismic data and identify hydrocarbon-bearing prospects that were previously more difficult to evaluate.

     According to The Daily Synapse:

ExxonMobil has used AI to identify four new exploration opportunities in Guyana’s Stabroek Block, applying historical discovery data, drilling results and subsurface information to sharpen prospect evaluation. The work combines advanced analytics, machine learning, high-performance computing and next-generation seismic imaging to accelerate exploration, lower costs and improve discovery success rates.”

     Reprocessing and reinterpreting seismic data are part of the AI-identified prospects. CFO Neil Hansen and CEO Darren Woods recently commented on identifying the prospects. According to Rio Times:

Hansen said the work produced four new discovery opportunities above and beyond what the company had previously considered prospects. Chief executive Darren Woods framed the findings as confirmation that the company is, in his words, not done yet in Guyana.”

     Rio Times summarized the details of the announcement:




     Below, Deepwater Exploration Geoscientist Ryan Christiansen talks more about the AI model in a LinkedIn post, noting its 90% hindcast accuracy. He points out that the block is very well-studied, which makes the newly identified prospects intriguing. He also notes that, due to it being well-studied, AI-model training was enhanced by all that confirmed data and reserves. He also cautions that the technique may not work as well where there have been fewer wells drilled (less verified data) and less subsurface data available.









Case Study #2 – AI-Assisted Review of Old Water Flooded Fields Identified Potential Unswept Areas – An Eastern Oklahoma AI Screening Example by Susan Nash

     Geoscientist and former president of the American Association of Petroleum Geologists (AAPG), Susan Nash, wrote an article on LinkedIn that gives a plausible and practical method for using AI to assist in analyzing a mature oil field for remaining unswept oil after a water flood. In this case, the area is Eastern Oklahoma. The field was originally drilled before 1920 and was later waterflooded in the 1950s and 60s. In this case, there is suspicion that the marginal areas of the oil reservoir may not have been swept by the water.

     First, she notes that early drilling was not geologically determined, and the only stimulation method available was shooting with nitroglycerine, which is not thought to create a fracture network that extends very far beyond the wellbore. She notes that even though the field is densely drilled, it may not have been effectively drained. Early reporting may have misidentified zones and reservoir sands in an area with suspected reservoir compartmentalization, which is common with fluvial-deltaic reservoirs. She notes that shooting wells with nitroglycerine could also create confined induced fracture conduits that miss reservoir compartments or different sand benches. It also means well-spacing likely won’t be as good in predicting what may have been bypassed. She gives the following quote describing how to see the field, not attributed:

The field was drilled as a collection of wellbores, flooded as a collection of tracts, and must now be understood as a collection of flow units.”

     Below, she gives four potential scenarios of oil left behind in terms of apparent opportunity, where the oil may sit, evidence required, and common false positives.




     Below, she explains how her study was organized and the results of the desktop screening method:

The source stack combined a 1920s county production map and geological narrative, state waterflood-unit records, available well and completion information, modern field boundaries, and current surface-exclusion layers. AI-assisted methods were used to read and organize long historical documents, normalize formation and field aliases, parse quarter-quarter legal descriptions, compare early productive limits with later unit geometry, and maintain a structured evidence ledger. Human geological review remained essential wherever a local sand name could represent more than one bench or where a unit boundary might have followed a genuine reservoir limit.”

     Below are the results of the screening process, which ranked three tiers of potentially bypassed or unswept oil.



     She notes that AI did not generate prospects but was able to quickly sift through all the historical data and make determinations about dates, legal descriptions, reconciling well duplicates and formation names, and flagging contradictions. These are functions that remind me of what a colleague called “massaging the data,” though in a different context.

AI is also vital in testing data quality, identifying errors, classifying them accurately, and establishing harmonization. Furthermore, AI can evaluate waterflood design, implementation, and purpose, comparing them against available options.”

Crucially, AI made it easier to test competing explanations.”

     Next, she goes deeper and considers how agentic AI could be applied to the project, generate recommendations, and how human interactions fit into the process.

In an agentic system, a language model manages a multi-step workflow, selects tools, evaluates results, and routes work to specialized agents while operating within defined guardrails and human approval points.”

     The table below gives eight types of AI agents, their functions, and outputs that can be applied to the project. That work is then examined by geologists, reservoir engineers, and, in some cases, land, HSE, and regulatory personnel, and tweaked as they see fit.




     Finally, as shown below, she gives an outline of how an AI-assisted pilot project can be organized. She calls this a disproof sequence.




References:

 

AI Uncovers Four New Prospects in Guyana. Ryan Christianson. LinkedIn Post. August 2026.

The Unswept Margin: How an AI-Assisted Review of Pre-1920 Fields Identified Prospective Unswept Areas. Susan Nash. LinkedIn, Article. August 9, 2026. (23) The Unswept Margin: How an AI-Assisted Review of Pre-1920 Fields Identified Prospective Unswept Areas | LinkedIn

ExxonMobil applies AI to identify Guyana prospects. Daily Synapse. August 9, 2026. ExxonMobil applies AI to identify Guyana prospects – DailySynapse

ExxonMobil’s AI Breakthrough Signals New Era of Digital Exploration in Guyana, Caribbean Energy Week. August 7, 2026. ExxonMobil’s AI Breakthrough Signals New Era of Digital Exploration in Guyana

ExxonMobil AI Guyana Exploration Finds 4 New Oil Prospects. Lachlan Williams. The Rio Times. August 3, 2026. ExxonMobil AI Flags 4 New Guyana Oil Prospects | The Rio Times

 

No comments:

Post a Comment

        A new review study published in the journal Trends in Ecology & Evolution by scientists in Australia and Germany found that th...