Identification Information:
Citation:
Citation Information:
Originator: Alberta Energy Regulator
Originator: Alberta Geological Survey
Originator: Peterson, J.T.
Originator: Pawley, S.M.
Publication Date: 2023
Title:
Subcrop Extents of Geological Units at the Sub-Cretaceous Unconformity, Lower Athabasca Region, Alberta (GIS data, polygon features)
Geospatial Data Presentation Form: vector digital data
Series Information:
Series Name: Digital Data
Issue Identification: DIG 2022-0036
Publication Information:
Publication Place: Edmonton, Alberta, Canada
Publisher: Alberta Geological Survey
Online Linkage: https://ags.aer.ca/document/DIG/DIG_2022_0036.zip
Description:
Abstract:
The sub-Cretaceous unconformity is a major component of the three-dimensional geological model of Alberta. Underlying geological units intersect the sub-Cretaceous unconformity at an oblique angle, creating a subcrop area of each unit at the unconformity surface. This dataset is based on stratigraphic picks of the sub-Cretaceous unconformity identified by the truncation of underlying units for the Lower Athabasca region of Alberta. The study area covers NTS map sheets 73M, 74D, 83P, and 84A.
Purpose: To provide subcrop extent polygons of geological units intersecting the sub-Cretaceous unconformity.
Supplemental Information: Language: In English;
Time Period of Content:
Time Period Information:
Single Date/Time:
Calendar Date: 2022
Currentness Reference: publication date
Status:
Progress: Complete
Maintenance and Update Frequency: None planned
Spatial Domain:
Bounding Coordinates:
West Bounding Coordinate: -114.854924
East Bounding Coordinate: -109.083975
North Bounding Coordinate: 57.534979
South Bounding Coordinate: 54.505742
Keywords:
Theme:
Theme Keyword Thesaurus: none
Theme Keyword: data
Theme Keyword: digital data
Theme Keyword: geology
Theme Keyword: gis data
Theme Keyword: sub-cretaceous
Theme Keyword: subcrop edge
Theme Keyword: unconformity
Place:
Place Keyword Thesaurus: none
Place Keyword: 73l
Place Keyword: 73m
Place Keyword: 74d
Place Keyword: 74e
Place Keyword: 83i
Place Keyword: 83j
Place Keyword: 83o
Place Keyword: 83p
Place Keyword: 84a
Place Keyword: 84b
Place Keyword: 84g
Place Keyword: 84h
Place Keyword: alberta
Place Keyword: canada
Access Constraints: Public
Use Constraints:
Acknowledgement of the Alberta Energy Regulator/Alberta Geological Survey as the originator/source of this information is required as described in the Open Government License - Alberta.
Point of Contact:
Contact Information:
Contact Organization Primary:
Contact Organization: Alberta Geological Survey
Contact Person: AGS Information Manager
Contact Position: AGS Information Manager
Contact Address:
Address Type: mailing and physical
Address: Alberta Energy Regulator
Address: 4th Floor, Twin Atria Building
Address: 4999-98 Avenue NW
City: Edmonton
State or Province: Alberta
Postal Code: T6B 2X3
Country: Canada
Contact Voice Telephone: (780) 638-4491
Contact Facsimile Telephone: (780) 422-1459
Contact Electronic Mail Address: AGS-Info@aer.ca
Hours of Service: 8:00 a.m. to 12:00 p.m. and 1:00 p.m. to 4:30 p.m.
Cross Reference:
Citation Information:
Originator: Alberta Energy Regulator
Originator: Alberta Geological Survey
Originator: Peterson, J.T.
Publication Date: 2023
Title: Sub-Cretaceous Unconformity Picks, Lower Athabasca Region, Alberta (tabular data, tab-delimited)
Geospatial Data Presentation Form: tabular digital data
Series Information:
Series Name: Digital Data
Issue Identification: DIG 2022-0033
Publication Information:
Publication Place: Edmonton, Alberta, Canada
Publisher: Alberta Geological Survey
Online Linkage: https://ags.aer.ca/
Cross Reference:
Citation Information:
Originator: Alberta Energy Regulator
Originator: Alberta Geological Survey
Originator: Peterson, J.T.
Originator: Babakhani, M.
Publication Date: 2023
Title: Sub-Cretaceous Unconformity Elevation, Lower Athabasca Region, Alberta (gridded data, ASCII format)
Geospatial Data Presentation Form: raster digital data
Series Information:
Series Name: Digital Data
Issue Identification: DIG 2022-0034
Publication Information:
Publication Place: Edmonton, Alberta, Canada
Publisher: Alberta Geological Survey
Online Linkage: https://ags.aer.ca/
Cross Reference:
Citation Information:
Originator: Alberta Energy Regulator
Originator: Alberta Geological Survey
Originator: Peterson, J.T.
Originator: Babakhani, M.
Publication Date: 2023
Title:
Sub-Cretaceous Unconformity Paleotopography, Lower Athabasca Region, Alberta (gridded data, ASCII format)
Geospatial Data Presentation Form: raster digital data
Series Information:
Series Name: Digital Data
Issue Identification: DIG 2022-0035
Publication Information:
Publication Place: Edmonton, Alberta, Canada
Publisher: Alberta Geological Survey
Online Linkage: https://ags.aer.ca/
Cross Reference:
Citation Information:
Originator: Alberta Energy Regulator
Originator: Alberta Geological Survey
Originator: Peterson, J.T.
Originator: Babakhani, M.
Publication Date: 2023
Title:
Paleotopography of the Sub-Cretaceous Unconformity Surface, Lower Athabasca Region, Alberta (NTS 73M, 74D, 83P and 84A)
Geospatial Data Presentation Form: map
Series Information:
Series Name: Map
Issue Identification: MAP 633
Publication Information:
Publication Place: Edmonton, Alberta, Canada
Publisher: Alberta Geological Survey
Other Citation Details: ISBN: 978-1-4601-5365-9
Online Linkage: https://ags.aer.ca/
Data Quality Information:
Logical Consistency Report:
The polygons were exported as a series of shapefiles used to define the extent of each geological unit subcropping beneath the sub-Cretaceous unconformity.
Completeness Report:
The subcrop polygons delineate the complete extent of each geological unit subcropping beneath the sub-Cretaceous unconformity within the study area.
Positional Accuracy:
Horizontal Positional Accuracy:
Horizontal Positional Accuracy Report:
The horizontal accuracy of the subcrop polygons is unknown. Subcrop boundaries are based on the presence or absence of the subcropping geological unit. Factors affecting the positioning of the subcrop boundaries include well data spacing, the amount of wells used to determine the subcrop position, the accuracy of the elevation surface, and the accuracy of the subcrop line when drawn by the geologist. These polygons are produced at a regional scale and are not intended for local-scale studies.
Lineage:
Process Step:
Process Description:

Step 1: (Input) 20,575 picks of the sub-Cretaceous unconformity within the study area boundary were used to identify the extent of the subcropping geological units and delineate the subcrop polygons.

Step 2: (Creating subcrop polygons)

-Point locations attributed with the subcropping formation were converted to spatial geometries. The formation name, representing the target for prediction, was encoded as a factor/categorical variable type suitable for classification models.

- A suite of raster datasets was prepared from the elevation and elevation residual sub-Cretaceous surfaces. These raster datasets were used as the predictors in the model to describe the morphometry of the surfaces in terms of surface curvature, depth of depressions, height relative to local highs/lows in the surface, and the depth of channel-like forms. Additional predictors that describe the horizontal proximity to edges of the salt dissolution front were also used.

- A training set was generated by spatially querying/extracting the values of the raster predictors at the point locations so that their feature values can be associated with target variable.

- Multiple machine learning classifiers, consisting of K-nearest neighbours, linear discriminant analysis, naïve bayes, extremely randomized trees, and XGBoost were evaluated based on (a) their predictive performances using 10-fold cross-validation; and (b) the geological plausible of the predicted subcrop classification maps.

- The most performant and realistic model, XGBoost was selected as the model to use for the final map prediction. This predicted map was generalized/smoothed and converted to vector features.

-Boundaries were checked and modified manually to enforce stratigraphical relationships and honour data points.

Process Date: 2022
Spatial Data Organization Information:
Direct Spatial Reference Method: Vector
Point and Vector Object Information:
SDTS Terms Description:
SDTS Point and Vector Object Type: GT-polygon composed of chains
Point and Vector Object Count: 22
Spatial Reference Information:
Horizontal Coordinate System Definition:
Planar:
Map Projection:
Map Projection Name: NAD 1983 UTM Zone 10N
Transverse Mercator:
Scale Factor at Central Meridian: 0.9996
Longitude of Central Meridian: -123.0
Latitude of Projection Origin: 0.0
False Easting: 500000.0
False Northing: 0.0
Planar Coordinate Information:
Planar Coordinate Encoding Method: coordinate pair
Coordinate Representation:
Abscissa Resolution: 0.000000002220024164500956
Ordinate Resolution: 0.000000002220024164500956
Planar Distance Units: meter
Geodetic Model:
Horizontal Datum Name: D North American 1983
Ellipsoid Name: GRS 1980
Semi-Major Axis: 6378137.0
Denominator of Flattening Ratio: 298.257222101
Entity and Attribute Information:
Detailed Description:
Entity Type:
Entity Type Label: Subcretaceous Subcrop Polygon
Entity Type Definition: Subcrop extent polygons of geological units intersecting the sub-Cretaceous unconformity.
Entity Type Definition Source: Alberta Geological Survey
Attribute:
Attribute Label: FID
Attribute Definition: Internal feature number.
Attribute Definition Source: Esri
Attribute Domain Values:
Unrepresentable Domain: Sequential unique whole numbers that are automatically generated.
Attribute:
Attribute Label: Shape
Attribute Definition: Feature geometry.
Attribute Definition Source: Esri
Attribute Domain Values:
Unrepresentable Domain: Coordinates defining the features.
Attribute:
Attribute Label: fm_name
Attribute Definition: Name of the formation
Attribute Definition Source: Alberta Geological Survey
Attribute:
Attribute Label: Shape_Leng
Attribute:
Attribute Label: Shape_Area
Attribute Definition: Area of feature in internal units squared.
Attribute Definition Source: Esri
Attribute Domain Values:
Unrepresentable Domain: Positive real numbers that are automatically generated.
Distribution Information:
Distributor:
Contact Information:
Contact Organization Primary:
Contact Organization: Alberta Geological Survey
Contact Person: AGS Information Manager
Contact Position: AGS Information Manager
Contact Address:
Address Type: mailing and physical
Address: Alberta Energy Regulator
Address: 4th Floor, Twin Atria Building
Address: 4999-98 Avenue NW
City: Edmonton
State or Province: Alberta
Postal Code: T6B 2X3
Country: Canada
Contact Voice Telephone: (780) 638-4491
Contact Facsimile Telephone: (780) 422-1459
Contact Electronic Mail Address: AGS-Info@aer.ca
Hours of Service: 8:00 a.m. to 12:00 p.m. and 1:00 p.m. to 4:30 p.m.
Distribution Liability:
The Alberta Energy Regulator / Alberta Geological Survey (AER/AGS) licenses this information under the Open Government License - Alberta. Any references to proprietary software in our documentation, and/or any use of proprietary data formats in our releases, do not constitute endorsement by the AER/AGS of any manufacturer's product.
Metadata Reference Information:
Metadata Date: 20230203
Metadata Contact:
Contact Information:
Contact Organization Primary:
Contact Organization: Alberta Geological Survey
Contact Person: AGS Information Manager
Contact Position: AGS Information Manager
Contact Address:
Address Type: mailing and physical
Address: Alberta Energy Regulator
Address: 4th Floor, Twin Atria Building
Address: 4999-98 Avenue NW
City: Edmonton
State or Province: Alberta
Postal Code: T6B 2X3
Country: Canada
Contact Voice Telephone: (780) 638-4491
Contact Facsimile Telephone: (780) 422-1459
Contact Electronic Mail Address: AGS-Info@aer.ca
Hours of Service: 8:00 a.m. to 12:00 p.m. and 1:00 p.m. to 4:30 p.m.
Metadata Standard Name: FGDC Content Standard for Digital Geospatial Metadata
Metadata Standard Version: FGDC-STD-001-1998
Metadata Time Convention: local time
Metadata Access Constraints: none
Metadata Use Constraints: none