Erosion and deposition of fine-grained sediments from the Bay of Fundy

Sedimentology ◽  
1985 ◽  
Vol 32 (6) ◽  
pp. 815-832 ◽  
Author(s):  
CARL L. AMOS ◽  
DAVID C. MOSHER
Keyword(s):  
Bay Of Fundy ◽  
Erosion And Deposition ◽  
Fine Grained

scholarly journals Theory of glacial erosion, transport and deposition as a consequence of subglacial sediment deformation

1996 ◽  
Vol 42 (140) ◽  
pp. 43-62 ◽  
Author(s):  
G.S. Boulton
Keyword(s):  
Large Scale ◽  
Dynamic Behaviour ◽  
Ice Sheets ◽  
Horizontal Distribution ◽  
Glacial Cycle ◽  
Dispersal Patterns ◽  
Erosion And Deposition ◽  
Fine Grained ◽  
Vertical And Horizontal Distribution ◽  
Sediment Deformation

AbstractA theory of erosion, transport and deposition of unlithified sediments by glaciers is presented. It predicts the large-scale areal distribution of zones and rates of erosion and deposition in time and space through a complete glacial cycle, together with the resultant intensity of large-scale lineations (drumlins) which will be incised in the landscape. The theory also predicts the dispersal patterns of subglacial lithologies, together with the form of dispersal trains derived from distinctive sources and the vertical and horizontal distribution of lithologies within a till. It predicts major erosional discontinuities within tills and the formation of boulder pavements. It suggests that the dominant proportion of the lowland tills produced by Pleistocene mid-latitude ice sheets was generated by subglacial deformation and explains why they are predominantly fine-grained.The theory is based on an analysis of glacier-dynamic processes and therefore can be used to infer the dynamic behaviour of former ice sheets from the distribution of tills and their lithologic composition.

Geochemical factors controlling the accumulation and dispersal of heavy metals in the Bay of Fundy sediments

1982 ◽  
Vol 19 (5) ◽  
pp. 930-944 ◽  
Author(s):  
D. H. Loring
Keyword(s):  
Source Rocks ◽  
Bay Of Fundy ◽  
Fine Grained ◽  
Anthropogenic Inputs ◽  
Geochemical Factors ◽  
Industrial Sources ◽  
High Concentrations ◽  
Abundance And Distribution ◽  
Local Anomalies ◽  
Nova Scotian

Total Zn, Cu, Pb, Co, Ni, Cr, V, Hg, Be, As, Ba, and Se concentrations vary regionally and in response to textural variations of the sediments of the Bay of Fundy. They are, except for local anomalies, at or near natural levels in relation to their source rocks and other unpolluted marine sediments.Chemical partition indicates that small but significant amounts (1–27%) of the total element concentrations are potentially available to the biota. Potential bioavailable metals are derived from natural and industrial sources and are held in the sediments by fine grained organic material (Hg, Pb), hydrous iron oxides (Cr, V, Co, Pb), ion exchange positions (Zn), and calcareous components (Cu, Zn, Ba).Of the total metal content, however, 73–99% is not readily available to the biota but held in various sulphide (Zn, Cu, Pb, As, Se), oxide (Cr, Ni, Co, V), and silicate minerals (Cr, V, Co, Ni). The host minerals have accumulated at the same rates as other detrital material except for particles of zinc oxide that have been derived from industrial sources adjacent to the Bay of Fundy. The accumulations of fine grained host minerals are the main control on the abundance and distribution of Hg, Be, Zn, Pb, and As in the sediments whereas the dispersal of the ferromagnesian silicates and various oxide minerals, rather than the grain size of their hosts, accounts for dispersal of Cr, V, Co, and Ni in the sediments. These factors together with the present depositional pattern of the particles account for the accumulation and relative enrichment of most metals along with other fine grained materials in the "Quoddy region" of the bay. Local anomalies of detrital minerals related to bedrock exposures also account for high concentrations of Cr, V, and Ni in the vicinity of Grand Manan Island and along the Nova Scotian coast. Relatively high metal concentrations also occur near a dredge dispersal site off St. John Harbour and may reflect the initial impact of anthropogenic inputs on the natural levels of metals in the Fundy sediments.

In situ erosion measurements on fine-grained sediments from the Bay of Fundy

1992 ◽  
Vol 108 (2) ◽  
pp. 175-196 ◽  
Author(s):  
Carl L Amos ◽  
G.R Daborn ◽  
H.A Christian ◽  
A Atkinson ◽  
A Robertson
Keyword(s):  
Bay Of Fundy ◽  
Fine Grained

scholarly journals Theory of glacial erosion, transport and deposition as a consequence of subglacial sediment deformation

1996 ◽  
Vol 42 (140) ◽  
pp. 43-62 ◽  
Author(s):  
G.S. Boulton
Keyword(s):  
Large Scale ◽  
Dynamic Behaviour ◽  
Ice Sheets ◽  
Horizontal Distribution ◽  
Glacial Cycle ◽  
Dispersal Patterns ◽  
Erosion And Deposition ◽  
Fine Grained ◽  
Vertical And Horizontal Distribution ◽  
Sediment Deformation

AbstractA theory of erosion, transport and deposition of unlithified sediments by glaciers is presented. It predicts the large-scale areal distribution of zones and rates of erosion and deposition in time and space through a complete glacial cycle, together with the resultant intensity of large-scale lineations (drumlins) which will be incised in the landscape. The theory also predicts the dispersal patterns of subglacial lithologies, together with the form of dispersal trains derived from distinctive sources and the vertical and horizontal distribution of lithologies within a till. It predicts major erosional discontinuities within tills and the formation of boulder pavements. It suggests that the dominant proportion of the lowland tills produced by Pleistocene mid-latitude ice sheets was generated by subglacial deformation and explains why they are predominantly fine-grained.The theory is based on an analysis of glacier-dynamic processes and therefore can be used to infer the dynamic behaviour of former ice sheets from the distribution of tills and their lithologic composition.

The petrology of North Mountain basalts from the wildcat oil well Mobil Gulf Chinampas N-37, Bay of Fundy, Canada

1987 ◽  
Vol 24 (6) ◽  
pp. 1255-1260 ◽  
Author(s):  
John D. Greenough ◽  
V. S. Papezik
Keyword(s):  
Geochemical Characteristics ◽  
Bay Of Fundy ◽  
Oil Well ◽  
Fine Grained ◽  
The North ◽  
Lower Unit ◽  
Ree Patterns ◽  
Middle Unit

Basalts totalling 236 m in thickness were intersected in the wildcat oil well Mobil Gulf Chinampas N-37 in the Bay of Fundy. A 5.5 m section of conventional core retrieved from the middle of the basalt section sampled two fine-grained, phenocryst-poor, amygdaloidal basalt flows. The basalts, though somewhat altered, show concentrations of ferromagnesian elements (e.g., Fe, Mg, Cr, Ni) and immobile elements (e.g., Zr, Nb, Ta, Hf) as well as chondrite-normalized REE patterns typical of high-Ti quartz-normative tholeiites and are identical to more evolved samples of the North Mountain basalts at Digby. These petrographic and geochemical characteristics allow correlation with middle unit flows of the North Mountain basalts. The lower unit of North Mountain basalt may be as thick in the well as in the Digby area (~200 m), but the upper unit is either missing or very thin (< 68 m). A 25 m thick sedimentary section just above the conventional core but within the basalt sequence has not been reported on land and hints at the existence of a basalt unit not present on North Mountain. The conclusion that North Mountain basalts occur in the Chinampas well suggests that the flows underlie most of the Bay of Fundy, originally covered 9400 km2, and had a total volume of 2350 km3.

Application of an image management system in microscopy

1992 ◽  
Vol 50 (2) ◽  
pp. 1052-1053
Author(s):  
Richard S. Chemock
Keyword(s):  
Data Storage ◽  
Cost Savings ◽  
Image Data ◽  
Analytical Techniques ◽  
Operational Mode ◽  
Fine Grained ◽  
Image Recording ◽  
Primary Output ◽  
Capacity Data ◽  
Image Management System

One of the most common tasks in a typical analysis lab is the recording of images. Many analytical techniques (TEM, SEM, and metallography for example) produce images as their primary output. Until recently, the most common method of recording images was by using film. Current PS/2R systems offer very large capacity data storage devices and high resolution displays, making it practical to work with analytical images on PS/2s, thereby sidestepping the traditional film and darkroom steps. This change in operational mode offers many benefits: cost savings, throughput, archiving and searching capabilities as well as direct incorporation of the image data into reports.The conventional way to record images involves film, either sheet film (with its associated wet chemistry) for TEM or PolaroidR film for SEM and light microscopy. Although film is inconvenient, it does have the highest quality of all available image recording techniques. The fine grained film used for TEM has a resolution that would exceed a 4096x4096x16 bit digital image.

Use of fractals to describe microstructures of porous thick-film platinum electrodes

1992 ◽  
Vol 50 (1) ◽  
pp. 314-315
Author(s):  
Steven D. Toteda
Keyword(s):  
Fractal Dimension ◽  
Power Plants ◽  
Electrical Response ◽  
Cubic Phase ◽  
Platinum Electrodes ◽  
Fine Grained ◽  
Impedance Response ◽  
Platinum Particles ◽  
Energy Surfaces ◽  
Highly Porous

Zirconia oxygen sensors, in such applications as power plants and automobiles, generally utilize platinum electrodes for the catalytic reaction of dissociating O2 at the surface. The microstructure of the platinum electrode defines the resulting electrical response. The electrode must be porous enough to allow the oxygen to reach the zirconia surface while still remaining electrically continuous. At low sintering temperatures, the platinum is highly porous and fine grained. The platinum particles sinter together as the firing temperatures are increased. As the sintering temperatures are raised even further, the surface of the platinum begins to facet with lower energy surfaces. These microstructural changes can be seen in Figures 1 and 2, but the goal of the work is to characterize the microstructure by its fractal dimension and then relate the fractal dimension to the electrical response. The sensors were fabricated from zirconia powder stabilized in the cubic phase with 8 mol% percent yttria. Each substrate was sintered for 14 hours at 1200°C. The resulting zirconia pellets, 13mm in diameter and 2mm in thickness, were roughly 97 to 98 percent of theoretical density. The Engelhard #6082 platinum paste was applied to the zirconia disks after they were mechanically polished ( diamond). The electrodes were then sintered at temperatures ranging from 600°C to 1000°C. Each sensor was tested to determine the impedance response from 1Hz to 5,000Hz. These frequencies correspond to the electrode at the test temperature of 600°C.

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