Story context revision — narration, visual sources and timing.
The revised opening establishes the place, period, purpose and stakes of the story. The tables below identify the new material and map each retained section to the corrected original film.
Original equipment review and visual credits remain the source record for the retained material. Times on that earlier page refer to the original master; the mapping below gives their positions in this edition.
Download the structured credits and timing record
New narration and its sources
A discovery and the geology it revealed
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Southwest of Edmonton, Imperial Oil was searching for petroleum in rocks hidden beneath the prairie. In nineteen forty-seven, Leduc Number One demonstrated a discovery that helped transform Alberta's oil industry. Its first productive interval was the Nisku. Later wells opened the deeper Leduc reef reservoir. This episode follows how seismic work, drilling and rock samples turned a prospect into a field, and how each new well changed the geological picture. We begin on the winter day when the discovery was shown to the public.
Alberta Energy Heritage: Preparation for the Leduc Discovery — Official Alberta retrospective on the exploration that preceded Leduc. The familiar unsuccessful-well count is treated as retrospective shorthand for a regional program, not one crew repeatedly drilling an identical target.
Alberta Energy Heritage: Leduc Discovery Day — Official Alberta account incorporating Vern Hunter’s later recollection of discovery day. The visible flare was beside the derrick; the episode does not portray an invented derrick-top gusher.
J. L. Irwin, Alberta Oil Review 1946 (published March 1947) — Contemporary provincial report, printed page 9, published in March 1947 despite the 1946 review-year title. Its early test figures describe different conditions, not a sustained daily forecast. The article reproduces only a limited 19-word excerpt.
NRCan / CSPG stratigraphic lexicon: Nisku Formation — Formal stratigraphic entry identifying D-2, the first productive interval of Leduc No. 1, with the later Nisku Formation. Its type-section depths are not No. 1 measurements.
NRCan / CSPG stratigraphic lexicon: Leduc Formation — Formal stratigraphic entry for the D-3 carbonate buildup later named the Leduc Formation. Reference-section depths and thicknesses are distinct from discovery-well measurements.
New visual sequences
Historical photographs and source documents retain their stated identity and attribution. Explanatory diagrams and typographic sequences are identified separately.
1947 · Southwest of Edmonton
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The actual Leduc No. 1 discovery-day installation.
Caption: Imperial Leduc No.1, 13 February 1947. A flame and black smoke rise beside the derrick; snow and earth banks are visible in the foreground.
Credit: Provincial Archives of Alberta, P2721
License: No known copyright restrictions (official Provincial Archives of Alberta Flickr Commons statement)
Layer and Imperial Oil staff, 1949 · NRCan stratigraphic lexicon
Caption: Conceptual stratigraphic section separating the No. 1 Nisku/D-2 interval from the deeper Leduc/D-3 buildup. Thicknesses and well spacing are schematic.
Credit: GeoNavigate original technical illustration; historical and geological sources credited below.
License: Original GeoNavigate explanatory artwork.