Bibliographic record
Abstract
R. Stewart A crosswell seismic survey was acquired in the Noel oilfield, northeastern British Columbia, by Z-Seis Corporation for BP Canada Energy Company in 2004. The goal was to obtain data for high-resolution imaging of gas-bearing, but tight, sandstone channels about 2500 meters deep in the Cadomin and Nikanassin formations. Recording between two wells approximately 150 meters apart employed hydrophones and a piezoelectric vibrator source. Seismograms were produced post-acquisition by cross-correlating detected vibrations with the pilot sweeps. The dominant frequencies in the crosswell seismograms are about 500 to 1500 Hz, suggesting wavelengths on the order of 5 to 10 m. Compared to wavelengths of about 100 meters that are usual for surface seismic data, the shorter crosswell wavelengths provide significantly better resolution of beds 10 to 25 m thick. Preliminary processing of the data included sorting and display of gathers, band-pass filtering, and first-arrival time-picking. A P-wave velocity tomogram was created from observed first arrival times using an iterative back-projection algorithm and accounting for refracted arrival times in the low-velocity zones. Velocities were found to be in the range of 5800 to 6200 m/s for sandstone, and 5100 to 5500 m/s for the siltstones and shales. The seismic boundaries imaged in the tomogram correlate excellently with natural gamma ray logs and the known geology. Future analysis of the dataset will include migration of the up-going and down-going reflected events. In addition, we intend to investigate possible anisotropy in the strata along with attenuation. The velocity values will be compared to sonic logs and surface seismic analyses.
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 machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.003 |
| Science and technology studies | 0.007 | 0.001 |
| Scholarly communication | 0.002 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.197 | 0.032 |
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 source (direct Gemma or distilled Codex), 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".