- Identification Information:
- Citation:
- Citation Information:
- Originator: Alberta Energy and Utilities Board
- Originator: Alberta Geological Survey
- Originator: Pawlowicz, J.G.
- Originator: Fenton, M.M.
- Publication Date: 200503
- Title: Drift Thickness of Peerless Lake Area, Alberta (NTS 84B) (GIS data, line features)
- Geospatial Data Presentation Form: vector digital data
- Series Information:
- Series Name: Digital Data
- Issue Identification: DIG 2005-10
- Publication Information:
- Publication Place: Edmonton, Alberta, Canada
- Publisher: Alberta Geological Survey
- Description:
- Abstract:
- The drift thickness map of the Peerless Lake area (NTS 84B) shows the variation in thickness of unconsolidated sediment lying between the bedrock surface and the present-day land surface, and complements the Drift Thickness of Alberta map (Pawlowicz and Fenton, 1995). The thickness of the drift varies from locally less than 2 metres in Buffalo Head Hills to over 200 metres in the Loon River Lowland in the central part of the map area. Thick drift fills the major paleovalleys, which are the Muskwa Valley, the Red Earth Valley and Gods Valley. The drift is thinnest on the Peerless Lake Upland, the Utikuma Uplands and the Buffalo Head Hills Upland. In general the areas of thin drift correspond to areas where the bedrock topography is high. Exceptions are the hills composed of thick drift, such as the ones located south of Muskwa Lake and southwest of Peerless Lake. These features are likely hill-hole pairs produced by glaciotectonism with lakes occupying the source depressions (holes). The drift also thickens in the southwestern part of the Utikuma Uplands. Experience from more detailed investigations in eastern Alberta have shown that unmapped, narrow, deep drift-filled channels are to be expected.
- Purpose: For depicting drift thickness in the Peerless Lake area (NTS84B) in GIS format.
- Supplemental Information:
- The drift thickness map represents the thickness of overburden between the land surface and the bedrock surface. Petrophysical logs were the primary source of information used for constructing the bedrock topography. A suite of the common well logs (gamma, resistivity, spontaneous potential, density, neutron, sonic and calliper) were useful in making the pick for top of bedrock; however, the gamma and resistivity logs proved to be the most useful. The drift typically displays a lower gamma response and higher resistivity response than the underlying bedrock. Other sources of data were water well lithologs, mineral exploration drillholes and outcrop information.
Mapping the bedrock surface was difficult in some areas where data were sparse. Many of the log traces were absent from the upper part of the hole because of surface casing. The depth of surface casing set in bedrock was used for an estimate of maximum drift thickness in places with few data. Conversely, many water wells did not penetrate deep enough to intersect the bedrock, so only a minimum drift thickness value could be determined.
The drift thickness interpretation was made after completion of the bedrock topography contouring. The bedrock topography contours were initially generated from bedrock surface picks using a computer-contouring program with some subsequent modifications by hand. The bedrock topography surface, in a digital grid format, was subtracted from a digital elevation model of the present-day surface. The resulting grid was then contoured to form an isopach map of the drift. Preliminary versions of this map were released as Alberta Geological Survey (AGS) publications by Pawlowicz and Fenton (2002) and Andriashek et al. (2001).
- Time Period of Content:
- Time Period Information:
- Range of Dates/Times:
- Beginning Date: 2000
- Ending Date: 2002
- Currentness Reference: process date
- Status:
- Progress: Complete
- Maintenance and Update Frequency: None planned
- Spatial Domain:
- Bounding Coordinates:
- West Bounding Coordinate: -116.024643
- East Bounding Coordinate: -113.976097
- North Bounding Coordinate: 57.018951
- South Bounding Coordinate: 55.996143
- Keywords:
- Theme:
- Theme Keyword Thesaurus:
- Theme Keyword: drift thickness
- Theme Keyword: bedrock topography
- Theme Keyword: buried valley
- Theme Keyword: overburden
- Theme Keyword: glacial drift
- Theme Keyword: preglacial
- Place:
- Place Keyword Thesaurus:
- Place Keyword: 84b
- Place Keyword: alberta
- Place Keyword: buffalo head hills
- Place Keyword: canada
- Place Keyword: peerless lake
- Access Constraints: Public
- Use Constraints: Credit to originator/source required. Commercial reproduction not allowed.
- Point of Contact:
- Contact Information:
- Contact Organization Primary:
- Contact Organization: Alberta Geological Survey
- Contact Person: Information Specialist
- Contact Position: Information Specialist
- Contact Address:
- Address Type: mailing and physical
- Address: Alberta Energy and Utilities Board
- Address: 4th Floor, Twin Atria Building
- Address: 4999-98 Avenue
- City: Edmonton
- State or Province: Alberta
- Postal Code: T6B 2X3
- Country: Canada
- Contact Voice Telephone: (780) 422-3767
- Contact Facsimile Telephone: (780) 422-1918
- Contact Electronic Mail Address: eub.ags-infosales@gov.ab.ca
- Hours of Service: 8:00 a.m. to 12:00 p.m. and 1:00 p.m. to 4:30 p.m.
- Data Set Credit: N.L. Clarke, E. J. Waters, M.C. Price
- Data Quality Information:
- Logical Consistency Report:
- The stratigraphic picks used to produce the bedrock surface and drift thickness contours were verified for each data point used. Contouring of the data was first done by a contouring program and then the contour lines were hand-edited on the computer to produce the final interpretation.
- Completeness Report:
- To generate the contour lines of the bedrock surface and drift thickness, data sources included oil and gas wells, water wells and geologic sections along rivers. Data from 1590 points were used. Of these data, 312 were oil and gas well geophysical logs with bedrock pick, 969 were oil and gas well geophysical logs with bedrock above top of well logs, 103 were water well lithologs with bedrock pick, 194 were water well lithologs with depth of bedrock lying below bottom of well, 9 were cross-sections with bedrock outcropping and 3 were cross-sections without bedrock outcrop.
- Positional Accuracy:
- Horizontal Positional Accuracy:
- Horizontal Positional Accuracy Report:
- Bedrock contour and drift thickness lines were edited to reflect a valley incision geological model and to honour each data point.
- Lineage:
- Process Step:
- Process Description:
- The drift thickness and structure contour of the bedrock surface maps were determined from bedrock stratigraphic picks made from three main sources: oil and gas wells, water wells and outcrops. In oil and gas wells, the bedrock picks were made using geophysical logs. From water wells and outcrop, lithologic decriptions were used to determine the depth to bedrock pick. Picks data were tabulated and imported into a contour-mapping software (MacCad v6.0) using a Macintosh desktop computer. The data were then gridded by triangulation using the Delaunay tuple method. The resultant grid was then contoured using the mapping software. The contour lines were then manually edited on the computer using the MacCad software. Next, the final contour lines were gridded again using 400 x 400 grid matrix to produce infill colour rendition. The drift thickness map was finally created by subtracting the bedrock surface grid from a grid of the ground surface topography. The resultant grid was then contoured to create the drift thickness map.
Final map preparation was as folows: the bedrock contour and gridded data were exported from MacCad in .dxf format and imported into ArcInfo v8.3. The attributes were deleted. The coverages were transformed from page units to real world coordinates (RMS error +/- 20 m) and projected to UTM12 NAD83. The contour lines were smoothed, tagged with the corresponding elevation/drift thickness values and exported to shapefiles. Map compilation was done using ArcGis v8.3.
- Process Date: 2004
- Spatial Data Organization Information:
- Direct Spatial Reference Method: Vector
- Point and Vector Object Information:
- SDTS Terms Description:
- SDTS Point and Vector Object Type: Complete chain
- Point and Vector Object Count: 294
- SDTS Terms Description:
- SDTS Point and Vector Object Type: Point
- Point and Vector Object Count: 4
- Spatial Reference Information:
- Horizontal Coordinate System Definition:
- Geographic:
- Geographic Coordinate Units: Decimal degrees
- Latitude Resolution: 0.000000
- Longitude Resolution: 0.000000
- Geodetic Model:
- Horizontal Datum Name: North American Datum of 1983
- Ellipsoid Name: Geodetic Reference System 80
- Semi-Major Axis: 6378137.000000
- Denominator of Flattening Ratio: 298.257222
- Entity and Attribute Information:
- Detailed Description:
- Entity Type:
- Entity Type Label: drift_84b_ll.aat
- Entity Type Definition: Line features
- Entity Type Definition Source: Alberta Geological Survey
- Attribute:
- Attribute Label: THICKNESS
- Attribute Definition: Difference in metres between ground elevation and bedrock surface elevation.
- Attribute Definition Source: Alberta Geological Survey
- Distribution Information:
- Distributor:
- Contact Information:
- Contact Organization Primary:
- Contact Organization: Alberta Geological Survey
- Contact Person: Information Sales Coordinator
- Contact Position: Information Sales Coordinator
- Contact Address:
- Address Type: mailing and physical
- Address: Alberta Energy and Utilities Board
- Address: 4th Floor, Twin Atria Building
- Address: 4999-98 Avenue
- City: Edmonton
- State or Province: Alberta
- Postal Code: T6B 2X3
- Country: Canada
- Contact Voice Telephone: (780) 422-3767
- Contact Facsimile Telephone: (780) 422-1918
- Contact Electronic Mail Address: eub.ags-infosales@gov.ab.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 and Utilities Board/Alberta Geological Survey (EUB/AGS) and its employees and contractors make no warranty, guarantee or representation, express or implied, or assume any legal liability regarding the correctness, accuracy, completeness or reliability of this publication. The data are supplied on the understanding that they are for the sole use of the user and will not be redistributed in any form, in whole or in part, to third parties. 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 EUB/AGS of any manufacturer's product.
- Metadata Reference Information:
- Metadata Date: 20050302
- Metadata Contact:
- Contact Information:
- Contact Organization Primary:
- Contact Organization: Alberta Geological Survey
- Contact Person: Information Specialist
- Contact Position: Information Specialist
- Contact Address:
- Address Type: mailing and physical
- Address: Alberta Energy and Utilities Board
- Address: 4th Floor, Twin Atria Building
- Address: 4999-98 Avenue
- City: Edmonton
- State or Province: Alberta
- Postal Code: T6B 2X3
- Country: Canada
- Contact Voice Telephone: (780) 422-3767
- Contact Facsimile Telephone: (780) 422-1918
- Contact Electronic Mail Address: eub.ags-infosales@gov.ab.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