scholarly journals A preliminary evaluation of stream sediment sampling for the detection of cobalt mineralization in the Bou Azzer District, Morocco

1983 ◽  
Author(s):  
M.P. Foose
Keyword(s):  
Stream Sediment ◽  
Preliminary Evaluation ◽  
Sediment Sampling

scholarly journals Stream sediment sampling in the Atâ area, central West Greenland

1988 ◽  
Vol 140 ◽  
pp. 24-26
Author(s):  
P.W.U Appel ◽  
C Knudsen
Keyword(s):  
Close Correlation ◽  
Stream Sediments ◽  
Stream Sediment ◽  
Amphibolite Facies ◽  
Gold Content ◽  
Sediment Samples ◽  
Sediment Sampling ◽  
Gneiss Granite ◽  
Field Season ◽  
Granite Complex

In 1982 scheelite was identified in stream sediments in the: Nuuk/Godthåb area, about 600 km south of Atâ. Subsequentlya regional stream-sediment programme was carried out in the Nuuk area from 1982 to 1987 as a result of which scheelite was found to be quite abundant in the 3800 m.y. old Isukasia supracrustalrocks as well as in the 3300 to 3000 m.y. old Malene supracrustal sequence (Appel, 1988). It was also recognised that there is a close correlation between the number of scheelite grains and the gold content of the heavy mineral concentrates in the Nuuk area (Appel, 1988). In the Ata area (fig. 1) extensive outcrops of supracrustal rocks are found. In these supracrustals, which have been metamorphosed to greenschist and amphibolite facies, abundant sulphide-rich horizons are found, as well as sulphide-bearing breccia zones with appreciable gold contents (Knudsen et al., 1988). During the 1987 field season geological reconnaissance mapping was carried out in two of the supracrustal areas and the gneiss-granite complex enclosing the supracrustal rocks ·was investigated (Knudsen et al., 1988). A limited programme of stream-sediment sampling was carried out in the Atâ area, where stream sediment samples were collected in all the main streams draining the supracrustal rocks.

scholarly journals Stratabound scheelite and stratiform tourmalinites in the Archaean Malene supracrustal rocks, southern West Greenland

1987 ◽  
Vol 156 ◽  
pp. 1-26
Author(s):  
P.W.U Appel ◽  
A.A Garde
Keyword(s):  
West Coast ◽  
Stream Sediment ◽  
Amphibolite Facies ◽  
The West ◽  
Late Archaean ◽  
Sea Floor ◽  
West Greenland ◽  
Sediment Sampling ◽  
Geological Map ◽  
Boron Complexes

The Malene supracrustal rocks form large enclaves in the late Archaean Nûk gneisses within an area of at least 36 000 km2 on the west coast of Greenland and have been repeatedly deformed and metamorphosed under amphibolite facies conditions. Stream sediment sampling has shown that scheelite occurs in the supracrustal enclaves throughout the area. It occurs stratabound in amphibolites, micaceous quartzites, siliceous cordierite-bearing metasediments and tourmalinites. A detailed geological map has been made of the central part of Store Malene mountain close to Nuuk. Banded metavolcanic Malene amphibolites and siliceous cordierite-bearing metasediments contain stratiform tourmalinites, often with appreciable scheelite, in addition to common accessory tourmaline. The tourmaiinites predate the earliest recognisable phase of deformation as well as prominent simple pegmatites. The tourmaline probably originated as primary sea floor precipitates, and the primary or diagenetic tourmaline crystals were later overgrown with tourmaline during metamorphism. The scheelite and tourmaline are probably syngenetic and of submarine exhalative origin, and boron complexes may have played a role in transporting tungsten in hot brines.

scholarly journals Bjørnesund Project, West Greenland

1992 ◽  
Vol 155 ◽  
pp. 24-27
Author(s):  
P.W.U Appel
Keyword(s):  
Hydrothermal Alteration ◽  
Late Stage ◽  
Mineral Resources ◽  
Stream Sediments ◽  
Stream Sediment ◽  
Heavy Mineral ◽  
Mineral Deposits ◽  
Mineral Potential ◽  
Sediment Sampling ◽  
Sampling Programme

The Bjørnesund Project is aimed at an evaluation of the mineral potential of the southernmost part of the municipality of Nuuk, between Bjørnesund and the large glacier Frederikshåb Isblink. One of the reasons that economic mineral deposits were expected to occur in the Bjørnesund area, was the presence of gold anomalies in heavy mineral concentrates from stream sediments (Appel, 1989). Another reason was the presence of anthophyllite-rich zones, presumed to have formed by hydrothermal alteration. At a fairly late stage in the planning of the field programme, the project was enlarged to include a regional geochemical stream sediment sampling programme in the area between 64°N and Bjørnesund. This latter part of the project was financed by a separate contribution from the Mineral Resources Administration, Ministry of Energy.

scholarly journals A new anorthosite/gabbro complex at Nûgssuaq, central West Greenland

1989 ◽  
Vol 145 ◽  
pp. 16-20
Author(s):  
A.A Garde ◽  
A Steenfelt
Keyword(s):  
Shear Zones ◽  
Field Work ◽  
Stream Sediment ◽  
Aerial Photographs ◽  
Geochemical Mapping ◽  
Considerable Part ◽  
West Greenland ◽  
Sediment Sampling ◽  
Geological Map

As part of the GGU activity in the Disko Bugt region, central West Greenland (Kalsbeek, 1989), the authors carried out helicopter-supported geological reconnaissance mapping and stream sediment sampling for geochemical mapping in the area between Jakobshavn Isfjord and Qarajaq Isfjord (fig. 1). A considerable part of the season was spent in the eastern part of the Nûgssuaq peninsula, partly to complete the stream sediment sampling initiated in 1986 (see Steenfelt, 1988) and also because previous geological field work in eastern Nûgssuaq was very limited. The existing geological map at a Rapp. Grønlands geol. Unders. 145. 16-20 (1989) scale of 1:500 000 covering Nûgssuaq is almost entirely based on interpretation of aerial photographs. During the field work large occurrences of hitherto unknown anorthosite/gabbro rocks and supracrustal sequences were discovered in the gneiss terrain. Both the anorthosite/gabbro and supracrustal units appear to be tectonically interleaved with strongly foliated, flat-Iying or shallowly south-dipping orthogneisses, which themselves contain numerous shear zones suggesting substantial subhorizontal movements.

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