Stratigraphic Architecture and Lithofacies Distribution in Meander-Belt Deposits, South Saskatchewan River and Cretaceous McMurray Formation, Alberta
Bibliographic record
Abstract
The (Aptian) McMurray Formation, the main reservoir in the Athabasca Oil Sands Region (AOSR), is dominantly comprised of heterolithic point-bar deposits contained within regionally-extensive meander belts. The influence of meander-belt geometry and point-bar stratigraphic architecture on lithofacies distribution in McMurray Formation point-bar deposits is poorly understood, despite the potentially adverse effects lithological heterogeneities have on reservoir fluid volume and movement. This goals of this project are: (1) investigate the geometry of composite channel-form bodies (CCFBs) (e.g., meander belts) in the McMurray Formation and determine if their external and/or internal characteristics link to reservoir distribution or quality; (2) establish a relationship between accretion-package geometry, migration style, and lithofacies distribution in McMurray Formation point-bar deposits; and (3) characterize and quantify point-bar sedimentation and erosion that occurs in meandering rivers during high-magnitude floods, events during which point-bar growth or retreat typically occur. Detailed geological mapping reveals that (1) average McMurray Formation CCFB thickness varies regionally and temporally, but average reservoir parameters are generally consistent between all CCFBs; (2) point-bar deposits located in McMurray Formation CCFBs have distinct intra-point-bar lithological heterogeneities that typically occur across discontinuity surfaces bounding point-bar accretion packages, particularly if the discontinuity is associated with a change in meander migration mode. Thus, seismic time-slice images can be used to predict the position of planform lithological heterogeneities in McMurray point-bar deposits, enabling prediction of reservoir compartmentalization; and (3) although extreme floods in meandering rivers are often catalysts for pronounced geomorphological change, an extreme-flood deposit on a point bar in a sand and gravel-bed meandering river is not typified by a single grain size or sedimentary structure; instead, it consists of beds with a coarser texture (particularly gravel, if available) than what is average for that location on the point bar. In addition to enhancing our knowledge of point-bar formative processes, these insights will refine the production-forecasting process for bitumen-producing reservoirs, improve prediction of regional sandstone trends in the McMurray Formation, and provide a foundation for investigations of upstream-downstream sedimentological, ichnological, and morphological trends that could shed light on the formative sedimentary processes that shaped deposits of the McMurray Formation.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".