Heavy minerals in stream sediments from Churchill Falls, Labrador—an aid in bedrock mapping

1980 ◽  
Vol 17 (2) ◽  
pp. 244-253
Author(s):  
John Edward Callahan
Keyword(s):  
Frequency Distribution ◽  
Mineral Content ◽  
Regional Metamorphism ◽  
Stream Sediments ◽  
Heavy Mineral ◽  
Heavy Minerals ◽  
Sediment Samples ◽  
Fluvial Deposits ◽  
Geologic Map ◽  
High Concentrations

Stream sediments from a 13 000 km2 previously glaciated area in central Labrador near Churchill Falls were examined for their heavy mineral content. The minus 0.25 mm (60 mesh) nonmagnetic heavy mineral fraction from 846 stream sediment samples consists mainly of magnetite, ilmenite. garnet, hornblende, epidote and minor clinopyroxene, orthopyroxene. kyanite. sillimanite, biotite. apatite, and zircon. Changes in the frequency distribution of epidote, hornblende, garnet, and sillimanite in the stream sediments correspond well with those reported in previously mapped underlying bedrock lithologies. The occurrence of kyanite and sillimanite, high concentrations of garnet and opaques (mainly ilmenite), and lower concentrations of hornblende and epidote were used to determine grades of regional metamorphism, resulting in revision of the geologic map of this area. Heavy minerals in glacial drift or fluvial deposits may be useful as an aid in mapping in glaciated areas.

scholarly journals Granulometry, heavy mineral and geochemical studies of stream sediments around Bula, Dass District, Northeast Nigeria

2020 ◽  
Vol 18 ◽  
pp. 63-73
Author(s):  
C. I. Adamu ◽  
E.E. Okon ◽  
D.O. Inyang
Keyword(s):  
Trace Elements ◽  
Stream Sediments ◽  
Stream Sediment ◽  
Heavy Mineral ◽  
Geochemical Data ◽  
Provenance Analysis ◽  
Sediment Samples ◽  
Granulometric Analysis ◽  
Elemental Analyses ◽  
Geochemical Studies

Active stream sediments generally consist of broken-down fragments of pre-existing rocks by the action of river (stream) flow. This makes them target materials for routine geochemical surveys and provenance analysis. Fifteen (15) stream sediment samples were collected in some parts of Bula and its environs, northeastern Nigeria, in order to determine their textural characteristics, heavy mineral and elemental composition. The sediments were subjected to granulometric, heavy mineral and elemental analyses. The result of granulometric analysis show that the streamsediments are poorly to moderately well sorted, very platykurtic to leptokurtic, fine to medium grained and positively skewed. Zircon, rutile and tourmaline are the dominant heavy mineral species occurring in the sediments. The computed Zircon-Tourmaline-Rutile (ZTR) index values for the samples range from 59.18 - 83.53, indicating mineralogical maturity. The geochemical data of the stream sediment samples show that the mean contents of the trace elements [Ti (0.73 ± 0.74%), Fe (0.39±0.19%), Cr (816±639ppm), Ni (258±108ppm), Pb (48±12.37ppm) and Zn (502±126ppm)] were higher than their respective average crustal values except for Fe. Computed threshold values indicate possible mineralization containing Fe and Ti. The elements have variable spatial distribution. The study shows that the trace elements composition of the stream sediments is majorly lithogenic. Because mineralization in rocks and sediments are often characterized by considerable variation in their trace elements contents, the metal concentrations in these sediments are large enough for Ilmenite and Rutile mineralization to be suspected within the study area.

scholarly journals Heavy mineral assemblages in tills and their use in distinguishing glacial lobes in the Great Lakes region

1979 ◽  
Vol 16 (12) ◽  
pp. 2219-2235 ◽  
Author(s):  
Q. H. J. Gwyn ◽  
A. Dreimanis
Keyword(s):  
Great Lakes ◽  
Mineral Content ◽  
Heavy Mineral ◽  
Heavy Minerals ◽  
Great Lakes Region ◽  
Adirondack Mountains ◽  
Magnetic Minerals ◽  
Grenville Province ◽  
Provenance Areas ◽  
Mineral Assemblages

Two main source areas of heavy minerals in tills have been defined in the Great Lakes region: a source in the Superior and Southern Provinces and another in the Grenville Province. The Superior–Southern source is typified by low heavy mineral content and high epidote percentage in contrast to the Grenville source which has a high content of heavy minerals of which garnet, tremolite, and to a lesser extent sphene and orthopyroxene are characteristic. The Huron lobe tills have a mineral suite characteristic of the Superior–Southern source. Two subsources can be distinguished in the Superior–Southern area; however, they are too limited in extent to be characteristic of major glacial lobes. Two other subsources have been identified in the Grenville provenance area: a western Grenville subsource containing abundant garnet and having a low purple–red garnet ratio; and an eastern Grenville subsource distinguished by high garnet and tremolite content and a garnet ratio generally greater than one. The western and eastern Grenville subsources are the provenance areas for the tills of the Georgian Bay lobe and the Ontario–Erie lobe respectively. A possible third Grenville subsource in the Adirondack Mountains is distinguished from other Grenville sources by a lower heavy mineral content and more abundant orthopyroxene and magnetic minerals. This assemblage may be characteristic of the southern portion of the Ontario–Erie lobe.

scholarly journals The Occurences of Heavy Mineral Placer at Kendawangan and Its Surrounding, West Kalimantan Province

2017 ◽  
Vol 32 (1) ◽  
Author(s):  
Agus Setyanto ◽  
Maman Surachman
Keyword(s):  
Heavy Metals ◽  
Coastal Area ◽  
Heavy Mineral ◽  
Heavy Minerals ◽  
Surrounding Area ◽  
West Kalimantan ◽  
Sediment Samples

The main objective of this study is to identify and to determine the variation and content of heavy mineral placer of Kendawangan coastal, offshore and its surrounding area. Sediment samples were taken from 18 locations, such as 12 samples from offshore and 6 samples from coastal area. For this analysis the heavy metals were identified and analyzed using isodynamic separator and binocular microscopic. The result indicates that heavy minerals consist of zircon, cassiterite, rutile, ilmenite, topaz, chalcopyrite, epidote, pyrite, hematite, hornblende and magnetite. Cassiterite and zircon are also found in sediment samples in all locations and potentially to be further developed. Keywords: Heavy minerals placer, Zircon, Cassiterite, Kendawangan, West Kalimantan Tujuan penelitian ini adalah untuk mengidentifikasi dan menentukan variasi kandungan mineral berat plaser pada sedimen pantai dan lepas pantai Kendawangan dan sekitarnya. Sampel sedimen diambil dari 18 lokasi yang terdiri atas 12 sampel sedimen lepas pantai dan 6 sampel sedimen pantai. Analisis dilakukan dengan menggunakan isodinamik separator dan mikroskop binokular. Hasil analisis menunjukkan bahwa mineral berat terdiri atas zircon, kasiterit, rutil, ilmenit, topas, kalkopirit, epidot, pirit, hematit, hornblende, dan magnetit. Kasiterit dan zircon juga dijumpai pada sampel sedimen di semua lokasi yang dianalisis dan berpotensi untuk dikembangkan lebih lanjut. Kata kunci: Mineral berat plaser, Zirkon, Kasiterit, Kendawangan, Kalimantan Barat

scholarly journals SEDIMENT DISTRIBUTION AND ITS RELATIONS TO CIRCULATION PATTERNS IN BOLINAS BAY, CALIFORNIA

1970 ◽  
Vol 1 (12) ◽  
pp. 86
Author(s):  
P. Wilde ◽  
T. Yancey
Keyword(s):  
Grain Size ◽  
San Francisco ◽  
Heavy Mineral ◽  
Heavy Minerals ◽  
Statistical Parameters ◽  
Sediment Distribution ◽  
Primary Mode ◽  
Marine Samples ◽  
Long Term Study ◽  
High Concentrations

Grain size and heavy mineral analyses of 6 cliff, 12 beach, and 44 marine sediment and rock samples from Bolmas Bay and its surrounding drainage area were done as part of a long term study of sediment transport on the continental shelf off Central California Sediments in the bay are predominately very fine sands Some samples, particularly adjacent to Duxbury Reef on the west, have a coarse sand to pebble component The primary mode of the marine samples is in the range 088 to 125 mm, whereas, the primary mode for beach material is from 175 to 25 mm The range of median diameters of the marine samples is from 07 to 14 mm The median diameters show a trend of decreasing grain size seaward parallel to the depth contours except opposite the entrance to Bolmas Lagoon where a tongue of relatively coarser material cuts across the depth contours The range of other statistical parameters are (1) sorting coefficient 1 10 to 1 41, (2) skewness 0 83 to 1 18, and (3) kurtosis 0 15 to 0 32 Our sediment studies indicate (1) The heavy mineral assemblage is predominantly green hornblende with secondary amounts of hypersthene and augite Glaucophane and jadeite occur in locally high concentrations near shore (2) The pattern of distribution of the heavy minerals shows (a) a tongue of high concentrations of minerals with a granitic source extending northwest from the San Francisco Bar, (b) flanked on the north and northeast by increasing landward concentrations of Franciscan metamorphic minerals (3) The major source of heavy minerals is the San Francisco Bar Secondary contributions come from Bolmas Lagoon and the adjacent cliffs (4) The circulation in the Bay is primarily counterclockwise, produced by a combination of wave refraction around Duxbury Reef and the tidal Coast Eddy Current The tidal influence, however, of Bolmas Lagoon is restricted to about one mile from the lagoon mouth.

scholarly journals Tungsandsforekomster i Danmark

1960 ◽  
Vol 33 ◽  
pp. 1-63
Author(s):  
Werner Christensen ◽  
Gunnar Larsen
Keyword(s):  
Mineral Content ◽  
Field Studies ◽  
Economic Importance ◽  
Heavy Mineral ◽  
Heavy Minerals ◽  
Large Deposits

Occurrences of heavy minerals along the coasts of Denmark have been investigated for the purpose of clarifying the question of to what extent these deposits contain minerals of economic importance in such quantities as to make extraction worth while.The plan included field studies of the nature and size of the occurrences as well as laboratory analyses of the mineral content in the sand.It has been ascertained that there are about 25 kilometres of beach in all with a high content of well-concentrated heavy mineral sand. The quantity of this sand is estimated at about 100,000 tons. Most of the large deposits were found to be in northern and western Jutland. It was ascertained that the following minerals assumed to be of economic importance were present: magnetite, ilmenite (containing haematite), and zircon. Other minerals, for example garnet, may prove useful as a by-product of extraction.

scholarly journals Anomalous radioactivity level and high concentrations of heavy minerals in Lemme area, South-West Estonia

Baltica ◽  
2014 ◽  
Vol 27 (2) ◽  
pp. 93-104 ◽  
Author(s):  
Anto Raukas ◽  
Rein Koch ◽  
Krista Jüriado ◽  
Johanna-Iisebel Järvelill
Keyword(s):  
Heavy Mineral ◽  
Heavy Minerals ◽  
Radiocarbon Dates ◽  
Radioactivity Level ◽  
Near Shore ◽  
Buried Soil ◽  
High Concentrations ◽  
The 1960S ◽  
The Baltic ◽  
Mineral Concentrations

Abstract As early as in the 1960s, extensive heavy-mineral concentrations containing zircon, monazite, and xenotime were discovered in the Lemme region of south-western Estonia. These concentrations contribute to the elevated radioactivity levels of the enclosing sediments. The near shore sands of the Litorina Sea contain up to 10-cm-thick interlayers with a heavy mineral content of up to 80%. These anomalous layers were formed during the transgressive phase and result from a complicated cross- and alongshore migration of sedimentary material, derived mainly from local Devonian bedrock. Radioactivity level in the study area is higher relative to the majority of the Devonian plateau. The Lemmeoja buried soil has 13 radiocarbon dates in an area of renewed interest for the investigation of the Baltic Sea history.

Sign in / Sign up

Export Citation Format

Share Document