scholarly journals A Study of the Heavy Mineral Distribution in the Bottom Sediments of Hudson Bay: Discussion

1983 ◽  
Author(s):  
A S Dyke
1998 ◽  
Vol 135 (3) ◽  
pp. 421-442 ◽  
Author(s):  
P. FAUPL ◽  
A. PAVLOPOULOS ◽  
G. MIGIROS

The terrigenous materials of the flysch deposits of the External Hellenides of mainland Greece have been characterized by their heavy mineral assemblages, based on 194 samples. Three major source types were distinguished. (1) A metamorphic source is shown by abundant garnet accompanied by traces of staurolite and chloritoid. In the source of the Pindos and Ionian zones, blueschist complexes were incorporated within the metamorphic terrains, demonstrated by the frequent occurrence of blue amphiboles. (2) The existence of ophiolitic sources is indicated by the occurrence chrome spinel. Pyroxenes, green amphiboles and partly epidote are related to volcanic/metavolcanic complexes. High ophiolitic detritus was especially found in Mid-Cretaceous turbiditic layers supplied from internal terrains. (3) Granitoid and gneiss source terrains are indicated, predominantly represented by zircon, tourmaline and apatite. This type of source is characteristic for Mid-Cretaceous turbidites sampled in western parts of the Pindos zone. In the terminal flysch deposits, granitoid detritus played only a subordinate role. An extensive recycling of Pindos Flysch material into the younger Western Hellenic Flysch can be excluded. Stratigraphic trends in the heavy mineral distribution of the terminal Pindos Flysch give insights into the changing tectonic situation of the source terrains. A regional east–west trend with changing ophiolitic detritus, observed in the Parnassos-Ghiona Flysch, points to a complex feeder system.


1986 ◽  
Vol 43 (3) ◽  
pp. 536-547 ◽  
Author(s):  
E. M. Levy

Background levels of petroleum residues in the form of particles floating on the sea and as substances extracted from the surface microlayer, the water column, and the surficial bottom sediments of the Hudson Strait/Foxe Basin and the Labrador shelf regions were measured during 1982 and 1983. No evidence of floating particulate oil was found in either region. Background levels of extractable petroleum residues in the surface microlayer were highly dependent on ambient sea conditions and ranged from 4.1 μg/L at the entrance to Hudson Strait to 28.3 μg/L on the southern Labrador shelf in 1982, and from 4.5 to 20.9 μg/L on the Labrador shelf in 1983 with the general background level at 8.13 μg/L. The background level in the water column in the Hudson Bay/Hudson Strait region was 0.46 μg/L in 1982 whereas that on the Labrador shelf was 0.42 μg/L during 1982 and 0.57 μg/L in 1983 (overall level of 0.51 μg/L). Concentration levels in the surficial bottom sediments depended primarily on the nature of the sediments and ranged from 1.9 μg/g at the eastern end of Hudson Strait to 52.5 μg/g on the continental slope east of Nain Bank with a general background level of 2.04 μg/g. These background levels are similar to those of other areas of the continental shelf off the east coast of Canada and are, presently, well below those known to have adverse biological consequences.


1977 ◽  
Vol 23 (3) ◽  
pp. 217-235 ◽  
Author(s):  
Frances Firek ◽  
G.L. Shideler ◽  
Peter Fleischer

2020 ◽  
Vol 67 (4) ◽  
pp. 575-590
Author(s):  
P. Poon ◽  
I. T. Graham ◽  
E. A. C. Liepa ◽  
D. R. Cohen ◽  
I. J. Pringle ◽  
...  

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