Miniature mud volcanoes and other injection features in tidal flats, James Bay, Québec

1976 ◽  
Vol 13 (3) ◽  
pp. 422-428 ◽  
Author(s):  
Jean-Claude Dionne
Keyword(s):  
East Coast ◽  
Fine Sand ◽  
Tidal Flats ◽  
Mud Volcanoes ◽  
James Bay ◽  
Marine Clay ◽  
Ice Floes ◽  
Mud Deposit

Miniature injection features, including mud volcanoes, dikes forming polygonal patterns, and isolated patches of clay, occur in tidal flats along the east coast of James Bay. They are formed by localized upward ejection of a mixture of fluidized marine clay, silt, and fine sand through a surficial recent mud deposit. Liquefaction is related to the melting of ice in the clayey deposit. Upward flowing of clay, silt, and fine sand seems to result from overloading by the overlying sediments having a higher degree of density, and possibly also by pressures of ice floes or/and icefoot.

Results of geoelectrical soundings for mapping of a marine clay along the Tangkak-Pagoh highway Johor, Malaysia

1989 ◽  
Vol 20 (2) ◽  
pp. 117
Author(s):  
A.G. Rafek ◽  
A.R. Samsudin
Keyword(s):  
Apparent Resistivity ◽  
Fine Sand ◽  
Convex Curve ◽  
Marine Clay ◽  
Borehole Data ◽  
Individual Layer ◽  
The North ◽  
Geoelectrical Resistivity ◽  
Good Agreement ◽  
Clay Horizon

Geoelectrical resistivity soundings conducted along the north-south expressway in the Tangkak-Pagoh area during its construction enabled the mapping of a marine clay which was present in alluvium. The apparent resistivity curves of the marine clay area, were characterised by low apparent resistivity values falling to almost zero, and a characteristic shape which was different from areas of weathered metasediments and weathered granite adjacent to this area. Apparent resistivities for both metasediments and granite were intermediate to high, with a distinct upward convex curve for metasediments and a flat upward convex curve for granite. Quantitative interpretation was able to distinguish between an upper and a lower clay horizon, which have differentconsistency and fine sand content. The thickness of the upper clay horizon, which varies between 8.0 m to 9.0 m according to borehole data showed good agreement with that obtained by resistivity soundings. The base of the lower clay horizon remained undetected by the resistivity soundings because of its very low specific resistivity. Using the thickness of weathered layers as observed along the road cuttings as a guide, good agreement between field data and calculated values was obtained in determining the specific resistivities and individual layer thicknesses for the granite and metasediment weathering profiles.

4. Archaeological Sites in the Galápagos Group

1956 ◽  
Vol 12 ◽  
pp. 13-21
Author(s):  
Thor Heyerdahl ◽  
Arne Skjölsvold
Keyword(s):  
Coastal Area ◽  
Rainy Season ◽  
Fine Sand ◽  
Dry Season ◽  
Archaeological Sites ◽  
Northwest Coast ◽  
James Bay ◽  
Local Conditions ◽  
Santiago Island

The principal site discovered by the expedition is on the northwest coast of James Bay, Santiago Island. The local conditions for primitive settlement are conspiciously better in this bay than in any other coastal area visited by the expedition in the Galápagos. To a passing craft James Bay opens up wide and impressive, well sheltered by forest-clad mountains sufficiently withdrawn from the coast to leave space for a large and level plateau lifted up like a terrace above the fine sand beaches of the bay (Fig. 3). In the rainy season glittering streams of water appear on the sides of a cone-shaped volcano (Sugar Loaf) and reveal from far out at sea the likely location of waterholes. Even in the dry season there are one or 2 dependable waterholes a couple of miles inland at the foot of this hill.

scholarly journals Subarctic tidal flats in areas of large tidal range, southern Baffin Island, eastern Canada

2011 ◽  
Vol 35 (2) ◽  
pp. 183-204 ◽  
Author(s):  
S. B. McCann ◽  
J. E. Dale ◽  
P. B. Hale
Keyword(s):  
Sea Ice ◽  
Intertidal Zone ◽  
Tidal Flats ◽  
Tidal Range ◽  
Baffin Island ◽  
Eastern Canada ◽  
Ice Breakup ◽  
Cumberland Sound ◽  
Ice Floes ◽  
Mode Of Transport

Wide, boulder-strewn intertidal flats occur around the head of Frobisher Bay and along parts of the shoreline of Cumberland Sound, in southeast Baffin Island. The coastal environment is characterized by large tidal ranges, severe winter sea ice conditions, and a relative sea level history which involves rapid and then decreasing land emergence during the earlier part of the Holocene, succeeded by slight recent submergence. Summer field investigations were carried out at two sites, Koojesse Inlet on Frobisher Bay, where ice breakup conditions were also monitored, and Pangnirtung Fiord off Cumberland Sound. The results are summarized under three headings: physical and biological zonation across the tidal flats; tidal action and sea ice processes; and geological evolution of the tidal flats. Comparisons are made with similar settings described by others in Labrador and Ungava Bay. The sedimentary shores at both Baffin Island sites exhibit a distinct physical zonation, most evident in the concentration of boulders in the middle tidal flat zone at Koojesse Inlet and in the boulder barricade at the seaward margin of the Pangnirtung flats. Biological observations show a zonation of intertidal flora and fauna across the intertidal zone at Koojesse Inlet. An outstanding problem concerns the mode of transport of very large boulders. Pushing and rolling, by ice floes which are confined to the intertidal zone by the solid ice in the offshore zone during the critical early phase of breakup may be more appropriate processes than ice rafting.

scholarly journals The Polar Bear and its Protection

Oryx ◽  
1956 ◽  
Vol 3 (5) ◽  
pp. 233-239 ◽  
Author(s):  
Alan G. Loughrey
Keyword(s):  
Sea Ice ◽  
Polar Bear ◽  
East Coast ◽  
Open Water ◽  
Large Degree ◽  
Hudson Bay ◽  
Large Size ◽  
Pack Ice ◽  
Time Of Year ◽  
Ice Floes

The polar bear, Thalarctos maritimus, (Phipps) enjoys such colloquial names as: “ice-bear,” “sea-bear,” “ice-tiger” and “ice-king.” In view of its large size and its supremacy over the other beasts of the ice-floes it well deserves these epithets. Primarily the polar bear is an animal of the broken arctic pack ice and is found in greatest numbers along the southern edge of the pack. It avoids large expanses of open water or frozen sea ice. The movements of the pack ice to a large degree determine its distribution and movements. Polar bears are carried southward with the pack ice in the spring and summer. In August and September when the ice begins to break up they generally come ashore and make their way north. At this time of year they may be found in considerable numbers along certain coasts where the sea ice has been brought by the winds, tides and currents. An Eskimo from Southampton Island, in northern Hudson Bay, informed me that in August, 1948, he and a companion counted over 180 of these bears along the east coast of that island.

scholarly journals Inventory of benthic amphipods from fine sand community of the Iberian Peninsula east coast (Spain), western Mediterranean, with new records

2010 ◽  
Vol 3 ◽  
Author(s):  
José Antonio De-La-Ossa-Carretero ◽  
Jean-Claude Dauvin ◽  
Yoana Del-Pilar-Ruso ◽  
Francisca Giménez-Casalduero ◽  
José Luis Sánchez-Lizaso
Keyword(s):  
Iberian Peninsula ◽  
East Coast ◽  
New Records ◽  
Fine Sand ◽  
Western Mediterranean

The movement of isolated boulders on tidal flats by ice floes

1982 ◽  
Vol 19 (4) ◽  
pp. 748-754 ◽  
Author(s):  
John J. Drake ◽  
S. B. McCann
Keyword(s):  
Coefficient Of Friction ◽  
Short Distance ◽  
Tidal Flats ◽  
Ice Thickness ◽  
Limiting Factor ◽  
Mechanism Analysis ◽  
Standard Format ◽  
Ice Roughness ◽  
Ice Floes ◽  
Distance Transport

The ability of ice floes to move isolated boulders on tidal flats by flotation and by pushing and (or) rolling them along the bed is considered in the standard format of sediment movement (entrainment, transport, and deposition). Analysis shows that flotation competence depends on ice thickness and floe size, and is sufficient to transport most of the boulders reported from eastern Canadian tidal flats. However, a limiting factor in the transportation of large boulders by this mode is likely to be the entrainment mechanism. Analysis of movement of grounded boulders by lateral ice thrust shows that, on both deformable and non-deformable beds, rolling rather than sliding will occur. Rolling competence depends on floe size, ice roughness, the ice–rock coefficient of friction, and current and (or) wind strength. Resistance to movement is a function of the embedment ratio and bed properties. Rolling could account for most of the observed short-distance transport of large boulders.

A STUDY OF THE MINERALOGICAL COMPOSITION OF SAND IN NORTHERN ONTARIO

1963 ◽  
Vol 43 (2) ◽  
pp. 189-200 ◽  
Author(s):  
Carol I. Dell
Keyword(s):  
Mineralogical Composition ◽  
Fine Sand ◽  
James Bay ◽  
Northern Ontario ◽  
Southern Ontario ◽  
Preliminary Study ◽  
James Bay Lowlands

A preliminary study of the mineralogical composition of the fine sand fractions of 51 samples of tills and stratified sands in northern Ontario was carried out. About 40 different minerals were identified in widely varying amounts. In all but a few samples, feldspar was the most abundant mineral while quartz was never the most abundant. Several deposits containing Palaeozoic limestone and dolomite fragments from the rocks of the James Bay lowlands were quite similar in composition to the calcareous southern Ontario deposits. Other samples, containing large amounts of pyroxenes, shale fragments or "greenstones", differed greatly from similar deposits in southern Ontario. The composition of the fine sand correlated well with the field classification of soils in this region, with a few exceptions.

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