21 resultados para volcanic rock


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Mathematical predictions of flow conditions along a steep gradient rock bedded stream are examined. Stream gage discharge data and Manning's Equation are used to calculate alternative velocities, and subsequently Froude Numbers, assuming varying values of velocity coefficient, full depth or depth adjusted for vertical flow separation. Comparison of the results with photos show that Froude Numbers calculated from velocities derived from Manning's Equation, assuming a velocity coefficient of 1.30 and full depth, most accurately predict flow conditions, when supercritical flow is defined as Froude Number values above 0.84. Calculated Froude Number values between 0.8 and 1.1 correlate well with observed transitional flow, defined as the first appearance of small diagonal waves. Transitions from subcritical through transitional to clearly supercritical flow are predictable. Froude Number contour maps reveal a sinuous rise and fall of values reminiscent of pool riffle energy distribution.

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Three cores from the Kearl Lake Oil Sands area within the Athabasca deposit of northeastern Alberta have been analyzed to understand the thermal history of the McMurray and Clearwater formations of the Lower Cretaceous Mannville Group. The approach involves the integration of vitrinite reflectance (VR), Rock-Eval pyrolysis, fluorescence microscopy, and palynology. Mean VR varies between 0.21 and 0.43% Ro and indicates thermally immature levels equivalent to the rank of lignite to sub-bituminous coal. Although differing lithologies have influenced VR to some extent (i.e., coals and bitumen-rich zones), groundwater influence and oxidation seem not to have measurably altered YR. Rock-Eval analysis points to Type III/IV kerogen, and samples rich in amorphous organic matter (ADM) show little to no fluorescence characteristics, implying a terrestrial source of origin. Palynology reveals the presence of some delicate macerals but lack of fluorescence and abundant ADM suggests some degradation and partial oxidation of the samples.

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A photograph of the construction at Baie Comeau, with the caption "'Sinking' dynamite for blast in rock immediately behind temporary staff house."

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A photograph of a large group/family photo on the rock steps of an outdoors location. There are nine individuals and one dog in the photograph.

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The description reads "(11) American Falls and "Rock of Ages" - Niagara, U.S.A."

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Indenture of deed of bargain and sale between Samuel Rock of Crowland Township and Samuel Street of the Town of Niagara for 1 acre in Lot no. 179 in the Town of Niagara – instrument no. 13070. A memorial of this record was made on Feb. 21, 1856, List B, Folio 169. An envelope addressed to Joseph Woodruff, Clerk of the Peace and postmarked Jan. 1857 was included with this document, July 17, 1840.