Foraminifera of the lower part of the Sully Formation (upper Albian), northeastern British Columbia

1983 ◽  
Vol 20 (8) ◽  
pp. 1248-1259 ◽  
Author(s):  
C. R. Stelck ◽  
A. S. Hedinger

An extensive microfauna of over 25 genera and 40 species of arenaceous foraminifera occurs in the lower Sully Formation on the Sikanni Chief River and consists of Bathysiphon spp., Hyperammina sp., Saccammina spp., Lituotuba? sp., Glomospira sp., Ammodiscus sp., Reophax spp., Haplophragmoides spp., Bigenerina sp., Ammobaculites spp., Ammotium sp., Haplophragmium spp., Trochammina spp., Ammobaculoides sp., Textulariopsis spp., Gaudryina sp., Orientalia sp., Eggerella sp., Gravellina sp., Verneuilinoides sp., Uvigerinammina sp., Pseudobolivina sp., Dorothia sp., Miliammina spp., and Psamminopelta sp.The suite occurs below the fish-scale marker bed of the Cretaceous Colorado Shale within the uppermost Albian portion of the Neogastroplites Zone. The assemblage defines the Haplophragmium swareni Subzone of the Miliammina manitobensis Zone of the Colorado Group. It is correlative with the middle Mowry Shale fauna of Wyoming.The suite is deep neritic (200 m) with some suggestion of salinity lessened slightly below normal marine. It is accompanied by an extensive microflora of pollen, spores, and dinoflagellates. The suite represents biofacies intermediate between those previously found at similar stratigraphic horizons within the Cruiser Shale of the Moberly Lake area of British Columbia (a shallower fauna) and within the type Shaftesbury Formation of Peace River, Alberta (deeper, or farther offshore).

1984 ◽  
Vol 21 (6) ◽  
pp. 731-736 ◽  
Author(s):  
Nathan L. Green ◽  
Paul Henderson

A suite of hy-normative hawaiites, ne-normative mugearite, and calc-alkaline andesitic rocks from the Garibaldi Lake area exhibits fractionated, slightly concave-upward REE patterns (CeN/YbN = 4.5–15), heavy REE contents about 5–10 times the chondritic abundances, and no Eu anomalies. It is unlikely that the REE patterns provide information concerning partial melting conditions beneath southwestern British Columbia because they have probably been modified substantially by upper crustal processes including crustal contamination and (or) crystal fractionation. The REE contents of the Garibaldi Lake lavas are not incompatible with previous interpretations that (1) the hawaiites have undergone considerable fractionation of olivine, plagioclase, and clinopyroxene; and (2) the individual andesitic suites were derived from separate batches of chemically distinct magma that evolved along different high-level crystallization trends. In general, however, the andesites are characterized by lower light REE contents than the basaltic andesites. These differences in LREE abundances may reflect different amounts of LREE-rich accessory phases, such as apatite, sphene, or allanite, assimilated from the underlying quartz diorites.


Blue Jay ◽  
1994 ◽  
Vol 52 (2) ◽  
Author(s):  
Norbert G. Kondla ◽  
Edward M. Pike ◽  
Felix A. H. Sperling

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