SE SASKATCHEWAN — ADDITIONAL OFFICIAL FORMATION MAP DATA

Scope
Nine formation/package isopach and zero-edge pairs from the Saskatchewan
Geological Survey SPFPS compilation (Marsh and Love 2014, Open File 2014-1).
Regional study envelope: longitude -105.0 to -101.2, latitude 49.0 to 51.0.
Suggested corridor zoom: [-104.05,49.65,-101.5,50.7].
The regional source grid spacing is 2 km. These are total formation/package
thickness contours, not net sand, net pay, porosity, oil volumes or prospects.
No new geological interpolation was performed.

Renderer interface
Read manifest.json. Paths are relative to this directory. Each formation has:
  render_isopach_path: ordinary positive physical-thickness contours only
  render_edge_path: dedicated official zero-edge features
  units, contour_interval_m, exact source title and original-map references
  edge_status: explicit statement when no mapped edge crosses this extent
  complete query/raw/clipped/ordinary/boundary/nonphysical feature counts

The raw/ files preserve entire source geometries selected by spatial intersection.
The clipped/ files contain exact intersections with the regional envelope.
An intersecting query can return whole multipart features extending far outside
the envelope; raw and clipped counts need not be identical.

Boundary encoding caution
Several official zero edges have positive ZLEVEL codes, and copies occur in the
isopach layer: Jurassic 3, Gravelbourg 2.1, Watrous 1.8, lower Watrous 1.8,
Torquay 1.5 and Birdbear 1.75. These must not be labelled as physical thickness.
prepare_layer_manifest.py separates them using their agreement with the dedicated
edge layer. Geometry equality is exact except Birdbear, where independent line
generalization yields an 8.964 m Hausdorff difference. The original geometries are
retained and the dedicated zero-edge layer is used for the map. The match method,
source IDs, numerical codes and measured discrepancy are recorded in manifest.
Cantuar has two records with ZLEVEL=-0.5. Their meaning is unresolved in the
metadata; they are preserved separately and omitted from physical-thickness plots.
Sign-only positive files are retained but are NOT the renderer input.

An empty edge file means no mapped zero edge crosses the selected extent.
It does not mean that a formation is absent. No separate Red Jacket, Yeoman or
Lake Alma member layer was found in the inspected service inventories.

Coordinates and accountability
Original services use NAD83(CSRS)/UTM zone 13N, WKID 2151/latest WKID 2957.
ArcGIS transformed retrievals to EPSG 4326 via outSR. No explicit datum-transform
override was supplied; the server default applies. Returned GeoJSON therefore
uses transformed longitude/latitude coordinates. No well coordinates were changed.
Queries use IDs and independent counts before batches of at most 200 features.
All IDs/counts were reconciled; all retained and clipped geometries validate.
Exact requests, source IDs and timestamps are retained under queries/.

Sources, unit checks and reuse
services/ retains service/layer metadata and ArcGIS item license statements.
All nine original published PDF legends were checked: contour values are metres.
Source interval/caption/URL/SHA256 evidence is in source_map_metadata.json and
manifest.json. source_maps/ contains the PDF/text verification copies. The PDFs
are not necessary for a lightweight derived-data archive if their metadata and
URLs are retained. Use the 2014 publication year, not the 2026 retrieval date, as the
date of geological interpretation. Map 32's catalogue entry says Cantaur; the
original map and layer correctly say Cantuar.

The ArcGIS item metadata licenses these layers under the Government of
Saskatchewan Standard Unrestricted Use Data Licence, Version 2.0. Credit the
Saskatchewan Mining and Petroleum GeoAtlas, the actual layers and retrieval date,
plus Marsh and Love 2014, Open File 2014-1 and relevant map numbers. Licence URL:
https://gisappl.saskatchewan.ca/Html5Ext/Resources/GOS_Standard_Unrestricted_Use_Data_Licence_v2.0.pdf

Reproduction
1. Run fetch_additional_layers.py (network access; Python and Shapely).
2. Run prepare_layer_manifest.py (local; Shapely and pyproj).
3. Run annotate_sources.py (local; uses retained source text and metadata).
The scripts can run from any working directory. A temporary dependency directory
/tmp/sesk_deps is used when present; otherwise installed Python packages apply.

Historical plates
Report 217 (Kreis 1991) contains local Wapella–Moosomin raster foldouts for
Watrous/Gravelbourg limits and Rocanville, Moosomin, Burrows and Rierdon isopachs.
Those PDFs were inspected as inventory candidates, but no contours were digitized
and they are not used in these consistent regional GIS layers. No modern Red Jacket
member geometry has been inferred from the regional Jurassic package layer.
