imported>The Space Enthusiast at 23:26, 25 June 2025

2025-06-25T23:26:38Z

New page

{{short description|Stratigraphic unit in Canada}}
{{Infobox Rockunit
| name = Bluesky Formation
| image = Bluesky_FM_sand.JPG
| caption = Bluesky Sandstone
| type = [[Geological formation]]
| age = {{Fossil range|Albian|Albian|Lower [[Albian]]}}
| prilithology = [[Sandstone]]
| namedfor = [[Bluesky, Alberta]]
| namedby = Peter C. Badgley, 1952
| region = Western [[Alberta]]
| country = Canada
| coordinates = {{coord|56.0442|N|118.1274|W|name=Bluesky Formation|display=inline}}
| unitof = [[Fort St. John Group]]
| underlies = [[Wilrich Member]]
| overlies = [[Gething Formation]]
| thickness = up to {{convert|46|m|ft|-1}}<ref name=lexicon>{{Cite web|url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:001560|title=Bluesky Formation|author=Lexicon of Canadian Geological Units|accessdate=2009-02-06|url-status=dead|archiveurl=https://archive.today/20120709174851/http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:001560|archivedate=2012-07-09}}</ref>
}}
The '''Bluesky Formation''' is a [[Stratigraphy|stratigraphic]] unit of [[Lower Cretaceous]] [[Geochronology|age]] in the [[Western Canadian Sedimentary Basin|Western Canada Sedimentary Basin]]. It takes the name from the hamlet of [[Bluesky, Alberta|Bluesky]], and was first described in [[Royal Dutch Shell|Shell's]] ''Bluesky No. 1'' well by Badgley in 1952.<ref>Badgley, Peter C., 1952. Notes on the subsurface stratigraphy and oil and gas geology of the Lower Cretaceous series in central Alberta (Report and seven figures); [[Geological Survey of Canada]], Paper No. 52-11, 12 p.</ref>

==Lithology and Depositional Environment==
The formation is composed of [[mudstones]], [[conglomerate (geology)|conglomerates]] and [[sandstones]] which can be quartzose or contain [[chert]] grains.<ref name=lexicon/> Many of the Bluesky sandstones do not display bedding features although some low and moderate-angle large scale cross-bedding has been observed in some sections.<ref name="geosciencebc.com">{{cite journal|last1=Petrel Robertson Consulting Ltd.|first1=Canadian Discovert Ltd.|title=Deep Subsurface Aquifer Characterization in Support of Montney Tight Gas Development: Geological Report|journal=Geoscience BC Report|date=June 2011|volume=2011-11|page=59|url=http://www.geosciencebc.com/s/Report2011-11.asp}}</ref> The sediments were deposited in both marginally marine nearshore and fully marine offshore settings following a [[transgression (geology)|transgression]] of the ancient Moosebar Sea.<ref>{{cite book|last1=Oppelt|first1=Harold|chapter=Sedimentology and Ichnology of the Bluesky Formation in Northeastern British Columbia|title=Sequences, Stratigraphy, Sedimentology: Surface and Subsurface|date=1988|series=CSPG Memoirs |volume=15|pages=401–415|chapter-url=http://archives.datapages.com/data/cspg_sp/data/015/015001/401_cspgsp0150401.htm|editor1=David P. James |editor2=Dale A. Leckie}}</ref> Bluesky sediments are separated from Gething strata by a scoured or loaded contact and occasionally by a burrowed ''[[Glossifungites]]'' surface.<ref name="geosciencebc.com"/> The Bluesky Formation can be very porous and produces hydrocarbons in many areas across Western Canada.<ref>{{cite book|last1=Hayes|first1=B.J.R|title=Cretaceous Mannville Group of the Western Canada Sedimentary Basin|publisher=Geological Atlas of the Western Canada Sedimentary Basin|url=http://www.ags.gov.ab.ca/publications/wcsb_atlas/a_ch19/ch_19.html|url-status=dead|archiveurl=https://web.archive.org/web/20130814133127/http://www.ags.gov.ab.ca/publications/wcsb_atlas/a_ch19/ch_19.html|archivedate=2013-08-14}}</ref> Heavy oil is produced from the Bluesky formation in the [[Peace River, Alberta|Peace River]] area.

==Distribution==
The Bluesky Formation reaches a thickness of {{convert|46|m|ft|sp=us}} in the [[Pouce Coupe River|Pouce Coupe]] area, and thins out toward north and west. Thin sands can be found in the [[Peace River (Canada)|Peace River]] area.

==Relationship with other units==
Although some early workers included the Bluesky Formation in the [[Bullhead Group]], it is usually classified as the basal unit of the [[Fort St. John Group]].<ref name=Mossop19>{{Cite web|url=http://www.ags.gov.ab.ca/publications/wcsb_atlas/a_ch19/ch_19.html|title=The Geological Atlas of the Western Canada Sedimentary Basin, Chapter 19: Cretaceous Mannville Group of the Western Canada Sedimentary Basin|others=Compiled by Mossop, G.D. and Shetsen, I.|author=Canadian Society of Petroleum Geologists and Alberta Geological Survey|year=1994|accessdate=2013-08-01|url-status=dead|archiveurl=https://web.archive.org/web/20130814133127/http://www.ags.gov.ab.ca/publications/wcsb_atlas/a_ch19/ch_19.html|archivedate=2013-08-14}}</ref> It is conformably overlain by the [[Wilrich Member]] of the [[Spirit River Formation]] and conformably underlain by the [[Gething Formation]]. Northeast of the town of [[Peace River, Alberta|Peace River]] it was deposited [[Unconformity|unconformably]] on [[Mississippian age|Mississippian]] limestone. It is equivalent with the [[Glauconitic Sandstone]] of the [[Mannville Group]] in [[central Alberta|central]] and [[southern Alberta]], as well as with the [[Wabiskaw Member]] of the [[Clearwater Formation]] in the eastern part of [[northern Alberta]].

==Bitumen Deposits==
The Bluesky deposit of bitumen comes from the "clean estuarine reservoir sands of the Cretaceous-age Bluesky Formation" in the [[Peace River]]. Secondary production area is the Gething Formation. The combined Bluesky-Gething deposit is the primary target area for [[oil sands]] development in the Peace River area. There is a reservoir at about {{convert|600|m|abbr=on}}–{{convert|700|m|abbr=on}} below the surface. Heavy oil in the Peace River, produced from bitumen deposit is extracted using wells not by mining.<ref name="AER_March_2014">{{citation |title=Report of Recommendations onOdours and Emissions in the Peace River Area |date=31 March 2014 |accessdate=23 December 2014 |work=AER |url=http://www.aer.ca/documents/decisions/2014/2014-ABAER-005.pdf }}</ref>{{rp|9}}

{{quote|The oil sands of the Bluesky-Gething were deposited during the Cretaceous Period within a transgressive system, with the lower fluvial to nonmarine Gething Formation at the base and the estuarine Bluesky Formation at the top. Deposition of the Bluesky-Gething reservoir and nonreservoir units was controlled by topography of the pre-Cretaceous unconformity. The Red Earth Highlands separate the Bluesky-Gething into northeast and southwest accumulations and includes part of the Seal Lake area. In the Peace River oil sands areas, the Bluesky-Gething is overlain by the marine shales of the Wilrich Member.|source=AER March 2014}}

==References==
{{reflist}}
{{WCSB|Northwest_Plains=yes}}

[[Category:Geologic formations of Alberta]]
[[Category:Cretaceous Alberta]]
[[Category:Sandstone formations of Canada]]
[[Category:Western Canadian Sedimentary Basin]]

{{Canada-geologic-formation-stub}}

Bluesky Formation - Revision history

imported>The Space Enthusiast at 23:26, 25 June 2025