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Showing 1 to 20 of 27 for “"heavy minerals"”.
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Correlation of Glacial sediments Using Heavy-Minerals Assemblages
<p>An optical study of the heavy minerals of the till in two lithostratigraphic units in Polk, Red Lake, and Norman Counties in northwestern Minnesota was undertaken. The purpose was to determine whether the assemblages are different enough to differentiate the two tills and whet her the …
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Heavy minerals of glacial sediments in the area of Red Lake Falls, Minnesota
… adjacent areas were studied to determine their heavy-mineral assemolages. Seventy-two samples of fine sand were studied by optical grain-count methods and 77 samples of fine sand were studied by x-ray diffraction methods. Most formations contain a hornblende-garnet-pyroxene-epidote assemblage; …
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Mineral Chemistry of Heavy Minerals in the Old Hickory Deposit, Sussex and Dinwiddie Counties, Virginia
… is the largest of a series of Pliocene (?) age heavy mineral sand deposits in Virginia and North Carolina. The high density of heavy minerals allows for selective concentration during transport and deposition. Under the right conditions, placers of considerable size can be formed. The …
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Heavy minerals of the Cretaceous Hell Creek and Paleocene Ludlow Formations of Slope and Bowman counties, North Dakota
… are nonmarine sediments of alluvial origin. The heavy minerals of these formations were specifically studied to determine the source rock types and their provenance, and generally assess the diagenetic processes which affected the heavy minerals. </p><p> The heavy minerals include zircon, rutile, …
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A geochemical investigation of ground water and soils affected by evaporation pond seepage, at the Namakwa Sands Mineral Seperation Plant(MSP)
… Sands an Anglo American plc operation, mines heavy minerals along the semi arid West Coast of South Africa. An acid effluent is generated during treatment of these heavy minerals. The effluent is neutralized and disposed of into unlined evaporation ponds. Seepage from the ponds affects the …
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Mineralogy and provenance of the TiO₂ - ilmenite heavy mineral sand deposit of Nataka
The Nataka heavy mineral sand deposit occurs along the northeast Mozambique coastline. It comprises a regional Pleistocene elliptical structure extending from Somalia, passing through Kenya, Tanzania, Madagascar and Mozambique, to Richards Bay in South Africa. The deposit consists of fine- to …
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The Lithology of Herman and Campbell Beach of Glacial Lake Agassiz in the Area of Larimore and Arvilla, North Dakota
… there is some in the coarser material. The heavy minerals found in both beaches are: magnetite, ilmenite, biotite, amphibole, tourmaline, and hyalophane.</p>
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Paleocene Turbidite Deposition in the Central American Seaway (NW Costa Rica): Geochemical Analysis and Provenance of Detrital Spinel and Clinopyroxene
… geochemical analysis of individual detrital heavy minerals from rock samples give indications of sediment sources and tectonic setting during deposition. This study is a provenance analysis based on (i) semi-quantitative energy-dispersive spectrometry analysis of heavy minerals, (ii) …
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Sedimentologic and Stratigraphic Significance of Boulder Layers in the Outer Coastal Plain of Southeastern Virginia
… Pleistocene Norfolk Formation. The sediments, heavy minerals and microfossils within the boulder layers in addition to boulder lithologies, dimensions and orientations were studied to determine the origin of these layers. These data indicate the boulder layers were separated into two similar …
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Geochemical tracers in the deep-sea and the North Sea
… impact on the coastal environment was studied. Heavy minerals indicate higher currents velocities, leading to a loss of fine fraction in recent tidal flat sediments. Today, heavy metal rich clay particles are only to a small extent deposited in the Wadden Sea area. The remaining permeable, …
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Reaction phenomena of iron oxide leaching in an evaporative acid bake reactor
Namakwa Sands is a heavy mineral mining and beneficiation business within Tronox, and produces two major products, zircon (zr02.Si02 99.9%) and rutile (Ti02 99.9%) at a combined annual rate of 140kt. The heavy mineral concentrates are exported to international markets to make specialist coatings …
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Stratigraphy and sedimentology of the Tongue River formation (Paleocene), southeast Golden Valley County, North Dakota
… to be finer grained, and to have fewer dark minerals than the overlying Sentinel Butte Member. Particle characteristics of both members indicate little chemical weathering, a short distance of transportation, and little reworking. Heavy minerals are indicative of a metamorphic source area …
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Elutriation Technology in Heavy Mineral Separations
… use of this relatively new technology to upgrade heavy mineral concentrates using Florida type ores. The intended use of this separatory device in this particular application is the removal of gangue quartz from other valuable heavy minerals such as ilmenite, leucoxene, rutile, zircon, and …
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Lode gold deposit characterization using evidence from stream sediments: an example from Brush Creek, Montgomery County, Virginia
Placer ore minerals are commonly intergrown with "relict" phases that coexisted with the ore mineral in the original lode deposit. Studying these relict phases can yield important information about the nature, and formation of the lode deposit. This type of study can be useful in areas with poor …
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The Semliki Basin, Uganda : its sedimentation history and stratigraphy in relation to petroleum accumulation
… and plagioclase feldspars with subordinate clay minerals. Accessory minerals, such as micas (biotite and muscovite), heavy minerals, garnet and epidote, are present in minor amounts. This mineralogy indicates that the sediments have a granitic and gneissose origin, related to continental-block …
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Detrital zircon geochronology of the Upper Miocene Boleo Formation in the Santa Rosalia, Baja California Sur, Mexico
… was constructed as a first step to concentrate heavy minerals and further processed in the lab using standard zircon separation methods yielding roughly 1,000 zircons per sample. We analyzed 315 zircons per sample by LA-ICPMS. Detrital zircon U-Pb ages from the Boleo Formation range dominantly …
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Provenance of Eastern Magallanes Foreland Basin Sediments: Mineralogical and Geochemical Analyses Reveal Paleogene Tectonic Unroofing of the Fuegian andes
… by forming the Drake Passage in the Scotia Sea. Heavy mineral composition data from the eastern Magallanes basin of southernmost South America indicate that Campanian to middle Eocene sediments had a mafic/ophiolitic provenance which is interpreted as being derived from the Patagonian-Fuegian …
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The Auborus Formation of the Bethanie district, South West Africa
… of quartz has taken place. The main heavy minerals are ore (largely specularite), garnet, epidote, zoisite, clinozoisite, mica, monazite, zircon and tourmaline. Zircon has been classified on colour, roundness, inclusions and zoning; tourmaline on colour, roundness and inclusions. …
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Mineralogic and Geochemical Variations within the Old Hickory Heavy Mineral Sand, Sussex and Dinwiddie Counties, Virginia
… and is presently operated by Iluka Resources. Heavy minerals constitute an average of 8% of the sediment, but locally reach concentrations as rich as 60%. The ore minerals, in order of decreasing concentrations, are ilmenite, rutile, and zircon, which are believed to have been derived from …
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Distribution of gold in soils and stream sediments and the use of cyanidation in exploration geochemistry
… and 53 μm (270 mesh, ASTM) and separation of heavy minerals (S.G. 3.3), samples were analyzed for gold by fire assay-atomic absorption spectroscopy (FA-AAS) and cyanide-AAS (CN-AAS). Results indicate that, on average, 70% of the gold in soils and 67% of the gold in stream sediments resides in …
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