(Written in order of depositional history, oldest at the top)
Borup Fiord Formation
- Early to Late Carboniferous
- Thickness ranges from 40 - 1100 m.
- Northern Axel Heiberg Island
- Red weathered Quartz Sandstone + Polymictic conglomerate
- Minor Arenaceous Limestone
- Locally abundant non-marine carbonate
- Interpreted as proximal alluvial fans grading into stream channel, braidplain, overbank on distal alluvial fans
Otto Fiord Formation
- Early to Late Carboniferous
- Up to 410 m thick
- Source of all evapouritic diapirs in central Sverdrup Basin
- Stratified, 8-50 m thick Anhydrite and Limestone cycles, rare dolostone and sandstone
- Diverse fossils present in limestones
- Localized brecciation
- Sparse halite on Axel Heiberg
Hare Fiord and Trappers Cove Formations
- Late Carboniferous
- Up to 1200 thick combined
- Siltstone, Shale, Siliceous Shale, Spiculitic Chert, Limestone
- Exposed on northern and eastern Axel Heiberg Island
- Strata occurs in incomplete Bouma cycles
Van Hauen and Black Stripe Formations
- Lower to Upper Permian
- Combined thickness between 180 to 360 m
- Result of sediment starvation
- Dark, fissile shale, dark siltstone, dark chert. Rare limestone
Blind Fiord Formation
- May be between 1000-1500 m thick
- Siltstone and shale, some red weathering
- Soft sediment deformation, cross bedding
- Annelid worm tracks (Zoophycos?)
- Late Permian to Early Triassic
- Contains cretaceous gabbro sills that conformably overlie the Van Hauen Formation
Blaa Mountain Group
- Contains four formations: Murray Harbour, Buchanan, Hoyle Bay, and Barrow Formations
- Dark shale, weathered siltstone, sandy siltstone
- Clay ironstone concretions
- 245.9-203.6 Ma
- Thin towards diapirs
Heiberg Formation
- Three members Romulus (pale sandstone, siltstone, shale, coarsening upwards cycles) Fosheim (light sandstone, less siltstone, carbonaceous shale, coal interbeds) Remus (light sandstone, quartz and iron cement, clay)
- Red weathering - iron likely comes from Fosheim member
- ~331-1422 m thick
- This formation is important evidence for the salt diaprism
Savik beds
- Composed of the Jameson Bay Formation, Sandy Point Formation, McConnell Island Formation, and Ringes Formation
- Lower Jurassic
- Dark grey to black shale, glauconitic shale and sandstone - Formations are grouped together because they are not possible to distinguish outside of the hand sample scale
- 270 m to 819 m in thickness
Awingak Formation
- Quartzose sandstone and shale
- Approximately 345 m thick
- Plant debris, coal, roots
- Thins by more than 50% adjacent to diapris
- Hornfels and breccias
- 161.2-161.8 Mya
- Debris flows
- Lots written about this - might be relevant to return to
Deer Bay Formation
- Kimmeridgian to mid-Valanginian (Late Jurassic to Early Cretaceous)
- Silty shale, clay ironstone interbeds, black silty shale
- Characterized by presence of glendonites
Isachsen Formation
- Valanginian to Aptian (Early Cretaceous)
- 92 to 1372 m in thickness
- Light quartz sandstone with lesser carbonaceous siltstone, shale and coal
- Coarsening upwards cycles
- Contains the Rondon Member (coarsening upwards cycles of shale, siltstone, bioturbated sandstone), the WalkerIsland Member (coarsening and fining upwards cycles of sandstone, carbonaceous siltstone and shale)
- Some mafic sills
Christopher Formation
- Dark shale and silty shale, minor siltstone, and very fine grained sandstone
- Total range in thickness 343 to >2100 m (including areas of thinning and minibasins, but generally 442-1100 m
- Early Cretaceous
- Splits into the Invincible Point Member and the McDougall Point Member, members are separated by the Junction beds at top of Invincible Point Member
- Invincible Point Member - lower 645 m of formation, dark silty shale, some ironstone and calcareous mudstone concretions, glendonites, petrified wood. Interbeds of sandstone, tuff, and siltstone, contains stratified anhydrite
- Junction beds - up to 60 m thick, coarsening and thickening upwards cross-bedded sandstones to the north
- Macdougall Point Member - dark silty shale, with siltstone and fine sandstone, concretions and petrified wood, 210-550 m
Hassel Formation
- 80% Sandstone, 20% shale, 5-20 m coarsening upwards cycles at Expedition Fiord
- Sandstones are medium grained calcarrious and dolomitic arkose and subarkoses at E
- 105 to > 500 m thick
- Covered by basalt and other mafic talus
- Early Cretaceous
Bastion Ridge Formation
- Early Cretaceous
- Shale, siltstone, minor thin beds of sandstone and sideritic ironstone
- 5-242 m thick
- Contains mafic sills and volcanic flows
Strand Fiord Formation
- Early to Late Cretaceous, may be conformable and contemporaneous with the Kanguk Formation
- Sucesssion of basalt, agglomerate, and pyroclastic deposits
- 40-1033 m thick
- Flows are 15-60 m thick
- Flow tops are vesicular and amygdaloidal
- Flows have aa, pahoehoe, and blocky textures
- Some hyaloclastic flows, ash-fall deposits and fluvial conglomerates
Intrusive igneous rocks
- Mafic
- Coarse to medium grained (gabbro-diabase)
- Dyke swams, including the Queen Elizabeth and Surprise dyke swarms (Surprise! It's a dyke swarm!)
- No strong relationship between age, trend, and stratigraphic level of emplacement
- Older dykes may have facilitated flows in younger units
- Early Creataceous - Ages of dykes are not well constrained at the Age level
Kanguk Formation
- Late Cretaceous
- Thickness between 31-847 m
- Dark shale, interbeds of sandstone and siltstone
Expedition Formation
- Late Cretaceous
- Comprises a lower and upper member
- Lower member is 160-947 m thick
- Lower member is ~60% shale, ~40% sandstone
- Sandstones in Lower member contain planar tabular cross-stratification, ripples, plant fragments, bioturbation, and is organized in both fining and coarsening upwards cycles
- Upper Member is 0-746 m thick
- Upper member is sandstone and shale in coarsening upwards cycles
- Upper member sandstone is medium to coarse grained cross-bedded sandstone
- Upper member grades into shale and carbonaceous shale to the west
- Upper member contains pebble lags
Strand Bay Formation
- 53 to 783 m thick
- Paleocene
- Shale dominated, with sandstone interbeds
- Coal seams
Iceberg Bay Formation
- Paleocene to Eocene
- Composed of the Lower Member and the Coal Member
- Full description in Ricketts (1991)
- Lower Member consists of 30-50% sandstone, shale, and coal
- Lower Member is up to 1838 m thick
- Lower Member consists of 15-45 m coarsening-upwards cycles
- The Coal Member is well preserved
- The Coal Member is up to 1060 m thick
- The Coal Member contains 1-10 m beds of fining upwards sandstone, coal, and shale
- The Coal Member contains fossil wood, lags of mud chips, and leaf imprints
Pleistocene and Holocene Sediments
- Gravels, Diamicts (till)
- Authors provide interpretations rather than unit descriptions
Jackson, M.P.A., and Harrison, J.C., 2006, An allochthonous salt canopy on Axel Heiberg Island,
Sverdrup Basin, Arctic Canada: Geology, v. 34, no. 12, p. 1045–1048, doi: 10.1130/G22798A.1.
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