New biostratigraphic data from the Lower Jurassic Fernie Formation in the subsurface of west-central Alberta and their stratigraphic implications

2003 ◽  
Vol 40 (1) ◽  
pp. 45-63 ◽  
Author(s):  
Michèle Asgar-Deen ◽  
Russell Hall ◽  
Jim Craig ◽  
Cynthia Riediger
Keyword(s):  
British Columbia ◽  
Red Deer ◽  
Gamma Ray ◽  
Lower Jurassic ◽  
The West ◽  
Fine Grained ◽  
Poker Chip ◽  
West Central ◽  
Gamma Ray Log

Geophysical gamma-ray log responses and examination of cores from select wells of the lower Fernie Formation document important correlations of several new lithologic units recognized in the subsurface of west-central Alberta. Ammonite faunas and coccolith floras recovered from these cores are illustrated and provide new ages for several of these units, requiring a revision of their correlation with surface stratigraphy of the west-central Alberta foothills. The organic-rich, fine-grained west-central Alberta subsurface lower Fernie Formation sediments are Hettangian to late Toarcian in age and are, therefore, correlative with outcrops of unnamed basal Fernie strata of northeastern British Columbia, Nordegg Member cherty limestones of the Cadomin and Nordegg areas, and with the Red Deer Member and Poker Chip Shale at outcrop in west-central Alberta.

New Lower Jurassic ammonite faunas from the Fernie Formation, southern Canadian Rocky Mountains

1987 ◽  
Vol 24 (8) ◽  
pp. 1688-1704 ◽  
Author(s):  
Russell L. Hall
Keyword(s):  
British Columbia ◽  
North American ◽  
Rocky Mountains ◽  
Red Deer ◽  
First Record ◽  
Lower Jurassic ◽  
Canadian Rocky Mountains ◽  
Poker Chip

New ammonite faunas are described from sections along Bighorn and Scalp creeks in central-western Alberta where Lower Jurassic parts of the Fernie Formation are exposed. The first record of the upper Sinemurian Obtusum Zone from the Fernie is based on the occurrence of Asteroceras cf. stellare and Epophioceras cf. breoni in the basal pebbly coquina on Bighorn Creek. The overlying Red Deer Member has yielded Amaltheus cf. stokesi, representing the upper Pliensbachian Margaritatus Zone; in immediately superjacent strata the first North American examples of ?Amauroceras occur together with Protogrammoceras and ?Aveyroniceras. In the basal parts of the overlying Poker Chip Shale a fauna including Harpoceras cf. falciferum, Harpoceratoides, Polyplectus cf. subplanatus, Hildaites cf. serpentiniformis, and Dactylioceras cf. athleticum is correlated with the lower Toarcian Falciferum Zone.The upper parts of the Poker Chip Shale on Fording River in southeastern British Columbia contain a fauna representing some part of the upper Toarcian, but owing to poor preservation, generic identifications are only tentatively made.

The Gordondale Member: designation of a new member in the Fernie Formation to replace the informal “Nordegg Member” nomenclature of the subsurface of west-central Alberta

2004 ◽  
Vol 52 (3) ◽  
pp. 201-214 ◽  
Author(s):  
M. Asgar-Deen ◽  
C. Riediger ◽  
R. Hall
Keyword(s):  
British Columbia ◽  
Source Rock ◽  
Lower Jurassic ◽  
Hydrocarbon Source Rock ◽  
Fine Grained ◽  
Maximum Thickness ◽  
West Central ◽  
Stratigraphic Nomenclature

Abstract New biostratigraphic data and revised lithostratigraphic correlations reveal that the current stratigraphic nomenclature for the Lower Jurassic portions of the Fernie Formation in the subsurface of west-central Alberta is inadequate. This paper introduces a new member, the Gordondale Member, for highly radioactive, fine-grained strata previously referred to as either the lower Fernie Formation, the Lower Fernie shelf limestone and clastics, the Nordegg Member, or the “Nordegg Member”. A new occurrence of a late Toarcian ammonite, which constrains the age of the top of the Gordondale Member, is also reported. The Hettangian to upper Toarcian Gordondale Member is an important hydrocarbon source rock and consists of dark brown, finely laminated, organic-rich, phosphatic and highly radioactive calcitic mudstones, calcilutites and fine-grained calcarenites. Fish fragments, pectinoid bivalves, Ostrea, belemnoids, ammonites, coccoliths and radiolarians are abundant. The Gordondale Member is laterally extensive and thins westward from a maximum thickness of approximately 50 m in the subsurface of west-central Alberta to 19 m at Pink Mountain in northeastern British Columbia.

The Lower Jurassic phosphorites of southeastern British Columbia and terrane accretion to western North America

1989 ◽  
Vol 26 (8) ◽  
pp. 1612-1616 ◽  
Author(s):  
T. P. Poulton ◽  
J. D. Aitken
Keyword(s):  
British Columbia ◽  
North America ◽  
Oceanic Crust ◽  
West Coast ◽  
Cold Water ◽  
Lower Jurassic ◽  
Depositional Model ◽  
Western North America ◽  
The West ◽  
Terrane Accretion

Sinemurian phosphorites in southeastern British Columbia and southwestern Alberta conform with the "West Coast type" phosphorite depositional model. The model indicates that they were deposited on or near the Early Jurassic western cratonic margin, next to a sea or trough from which cold water upwelled. This suggests that the allochthonous terrane Quesnellia lay well offshore in Sinemurian time. The sea separating Quesnellia from North America was partly floored by oceanic crust ("Eastern Terrane") and partly by a thick sequence of rifted, continental terrace wedge rocks comprising the Purcell Supergroup and overlying Paleozoic sequence. This sequence must have been depressed sufficiently that access of upwelling deep currents to the phosphorite depositional area was not impeded.

Wagnerite with isokite from the Benson Mines, west-central Adirondack Highlands, New York

1992 ◽  
Vol 56 (383) ◽  
pp. 227-233 ◽  
Author(s):  
Howard W. Jaffe ◽  
Leo M. Hall ◽  
Howard T. Evans
Keyword(s):  
New York ◽  
New York State ◽  
Index Of Refraction ◽  
The West ◽  
Space Group ◽  
Fine Grained ◽  
West Central ◽  
Wet Chemical ◽  
Image Position ◽  
Transverse Fractures

AbstractThe rare fluophosphate minerals wagnerite, ideally Mg2(PO4)F, and isokite, ideally CaMg(PO4)F, are intimately associated with magnetite-hematite deposits in sillimanite-, garnet-, and pyroxene-rich paragneisses and migmatites at the Benson Mines, near Star Lake in the west-central Adirondack Highlands of New York State. Coarsely crystalline wagnerite occurs in lenticular masses, typically 4 × 8 cm, delineated by sharply cross-cutting, sinuous, 2 cm-wide veins of fine-grained, fibrous to platy isokite and granular fluorapatite. These also penetrate transverse fractures across wagnerite lenses. Isokite formed from the introduction of Ca- and O-rich hydrothermal solutions into wagnerite. Both minerals are monoclinic: wagnerite crystallises in space group P21/a with a = 11.945, b = 12.717, c = 9.70 Å, β = 108.18°, V = 1400.2 Å3, D(calc) = 3.291 g/cm3 for Z = 16; isokite crystallises in space group A2/a with a = 6.909, b = 8.746, c = 6.518 Å, β = 112.20°, V = 364.7 Å3, D(calc) = 3.248 for Z = 4. Optical properties for wagnerite are: α = 1.5845, β = 1.5875, γ = 1.6010, 2V = 51°(calc.) disp = r < v weak, absorption α < β > γ with α = col., β = pale yel., γ = v. pale yel. For isokite only a mean index of refraction, n = 1.598, could be measured. Wet chemical analysis of wagnerite containing a calculated 11.4% of isokite as fine lamellae, gave the formula:

High-resolution late Paleozoic cyclostratigraphy and tectonic evolution of the Keeler Basin, California, southwest Laurentia

2021 ◽  
Author(s):  
Patrick J. Gannon ◽  
M. Elliot Smith ◽  
Paul J. Umhoefer ◽  
Ryan J. Leary
Keyword(s):  
Gamma Ray ◽  
Sediment Accumulation ◽  
Foreland Basin ◽  
R Package ◽  
Accumulation Rates ◽  
Fine Grained ◽  
Upper Paleozoic ◽  
Optimization Function ◽  
Scale Optimization ◽  
Gamma Ray Log

Cyclic strata exposed in the Inyo Mountains of eastern California contain a continuous 6 m.y. record of deep marine deposition that spans the Pennsylvanian−Permian boundary. To better understand the geologic evolution of southwest Laurentia and the role of glacially driven eustasy in upper Paleozoic stratigraphy, we measured two detailed ∼600 m composite stratigraphic sections of the Keeler Canyon Formation and collected a handheld spectral gamma ray log. Post-depositional deformation complicates field relationships, but 1:5000 scale mapping of faults and folds permits assembly of two continuous sections. Measured strata alternate at the 5−20 m scale between intervals of fine-grained laminated marlstone and intervals of mixed carbonate and siliciclastic turbidites and debrites. Based on facies characteristics and a prominent marker horizon, we reassign the Pennsylvanian-Permian age upper Salt Tram unit of the upper Keeler Canyon Formation to a new Estelle Member. We estimate sediment accumulation rates within the Keeler Canyon Formation using published conodont biostratigraphy and correlative U-Pb geochronology from Eastern Europe combined with spectral analysis and timescale optimization using the Astrochron R package. Evolutive harmonic analysis of gamma ray-derived element concentrations reveals prominent bundled periodicities that are consistent with both long and short eccentricity cycles. Average sediment accumulation rates calculated using the time scale optimization function of Astrochron suggest a gradual increase from 40−60 m/m.y. to ∼120 m/m.y. during the late Pennsylvanian and then a minima of ∼50 m/m.y. near the Pennsylvanian−Permian boundary, which is followed by an increase to ∼175 m/m.y. into the Early Permian. This trend in sediment accumulation rates and subsequent Permian contractile deformation are compatible with flexural subsidence in a SW-migrating foreland basin related to the southern part of the late Antler orogenic system.

Distribution of the Bandera Shale of the Marmaton Group, Middle Pennsylvanian of Southeastern Kansas

1998 ◽  
pp. 29-41
Author(s):  
Robert L. Brownfield ◽  
Robert L. Brenner ◽  
John P. Pope
Keyword(s):  
Cross Sections ◽  
Gamma Ray ◽  
High Energy ◽  
Sedimentary Characteristics ◽  
Fine Grained ◽  
Isopach Maps ◽  
Marine Influence ◽  
Carbonate Formations ◽  
Gamma Ray Log ◽  
Siliciclastic Sediments

In southeastern Kansas, the Middle Pennsylvanian (Desmoinesian) Bandera Shale consists of sandstone, shale, limestone, and coal deposited between two carbonate formations, the underlying Pawnee Limestone and the overlying Altamont Limestone. Isopach maps and cross sections indicate that the Bandera Shale thickens southeastward towards the Oklahoma and Missouri borders. Analysis of gamma-ray-log signatures, augmented by neutron-log signatures, indicates that the Bandera Shale is rich in mudstone, with sandstones limited to intervals ranging from 10 ft to 30 ft (3-9.1 m) in thickness. Comparisons with previously studied cored and logged siliciclastic portions of overlying Missourian lithologies suggest that the Bandera Shale consists of various proportions of sandstone, siltstone, clay-rich shale, and calcite-cemented sandstone. Exposures of the Bandera Shale in Bourbon County, Kansas, consist of interbedded shale and calcite-cemented, fine-grained sandstone. Sandstone beds, ranging from 3 cm to 20 cm (1.2-7.9 in) in thickness, are, in places, rhythmically laminated with organic-rich and organic-poor lamina forming 2-mm (0.8-in)-thick couplets. Many sandstone bedding surfaces in the lower and middle portion of the Bandera Shale are bioturbated with horizontal feeding trails and some vertical burrows that suggest marine environments. Thicker sandstone units are either trough cross-bedded, with sets up to 1.5 m (4.9 ft) thick, or amalgamated ripple cross-laminated and flaser-laminated. Outcrop observations coupled with subsurface analysis indicated that Bandera Shale in southeastern Kansas was deposited as a siliciclastic complex that prograded westward during a sea-level lowstand. Siliciclastic sediments may have been deposited in a clastic wedge or deltaic complex, but sedimentary characteristics observed in outcrops record marine influence at least along the margins of the complex. Rhythmic stratification within sandstone beds that are interbedded with shale resemble tidal features described elsewhere in the Pennsylvanian of North America and suggest that embayments were present where tidal cells were amplified along a morphologically irregular shoreline. Bioturbated sandstone units, interbedded with clay shale, record high-energy events that influenced sand distribution.

The population of Red Deer (Cervus elaphus L., 1758) in Tulcea county (Romania)

2010 ◽  
Vol 53 (1) ◽  
pp. 351-356
Author(s):  
Sorin Geacu
Keyword(s):  
Cervus Elaphus ◽  
Red Deer ◽  
Forest Land ◽  
The West ◽  
Spreading Area ◽  
Deer Population ◽  
The North ◽  
Natural Expansion ◽  
North Western

The population of Red Deer (Cervus elaphus L., 1758) in Tulcea county (Romania) The presence of the Red Deer in the North-western parts of Tulcea County is an example of the natural expansion of a species spreading area. In North Dobrogea, this mammal first occurred only forty years ago. The first specimens were spotted on Cocoşul Hill (on the territory of Niculiţel area) in 1970. Peak numbers (68 individuals) were registered in the spring of 1987. The deer population (67 specimens in 2007) of this county extended along 10 km from West to East and 20 km from North to South over a total of 23,000 ha (55% of which was forest land) in the East of the Măcin Mountains and in the West of the Niculiţel Plateau.

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