NMR Evaluation of Shale Oil Mobility: Combined Pyrolysis and CO2 Huff-N-Puff
Source abstract
Abstract
The occurrence and mobility of shale oil are critical issues in exploration and development. Shale reservoirs exhibit a complex fluid state, with oil and water present in various forms. The presence of organic matter and clay minerals within the reservoir framework further complicates the fluid’s occurrence and mobility. Utilizing two-dimensional nuclear magnetic resonance (NMR) experiments, in this study, core samples from the Shengli Oilfield’s shale oil reservoirs were analyzed. We conducted pyrolysis-NMR and CO2 huff-n-puff-NMR joint measurement experiments to assess the shale oil mobility. The results indicated that CO2 huff-n-puff was the most effective in the initial cycle, with diminishing returns in subsequent cycles, and NMR signal changes were predominantly observed in the movable oil fraction. The selected samples showed an average recovery rate of 26.9%, suggesting good mobility of shale oil in the study area. Based on the experimental results, a fluid component identification template for the study region was established, which mainly consists of the following five parts: movable oil, adsorbed oil, asphaltene, clay-bound water, structural water, and kerogen. This research provides valuable insights for the efficient development of shale oil reservoirs.
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Research context
OpenAlex topics: Hydrocarbon exploration and reservoir analysis · NMR spectroscopy and applications · Petroleum Processing and Analysis
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development, Beijing 102206, China
State Energy Center for Shale Oil Research and Development, Beijing 102206, China
State Key Laboratory of Deep Oil and Gas, China University of Petroleum (East China), Qingdao 266580, China
School of Geosciences, China University of Petroleum (East China), Qingdao 266580, China
Funding
State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development · State Energy Center for Shale Oil Research and Development
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