Qualitative Petrographic Interpretation of Potsdam Sandstone (Cambrian), Southwestern Quebec

1971 ◽  
Vol 8 (8) ◽  
pp. 853-882 ◽  
Author(s):  
D. W. Lewis
Keyword(s):  
Heavy Mineral ◽  
Heavy Minerals ◽  
Coarse Grains ◽  
Mineral Concentrations ◽  
Petrographic Study

The Cambrian Potsdam Group in southwestern Quebec comprises the quartzo-feldspathic Covey Hill Formation (up to 2000 ft (610 m) thick), and the unconformably overlying and overlapping Chateauguay Formation, which is subdivided into the lower Cairnside Member (up to 500 ft (152 m) thick) of pure quartz sandstone and the Upper Theresa Member of interlayered quartz sandstone and dolostone. Petrographic study concentrated on Covey Hill and Cairnside lithologies from three deep cores near Montreal. Traditional interpretation of Potsdam Sandstone as a pure quartz blanket deposited by transgressing seas applies only to the Cairnside Member.The Covey Hill Formation comprises subround-round sands, sparse rounded gravels, scattered penecontemporaneous clay clasts, and rare thin mud layers. Juxtaposition of well and poorly sorted laminations of different sand sizes, mica-clay, and heavy mineral concentrations, attests fluctuating depositional energies. Presence of silt-free clayey matrix and scattered coarse grains set amongst much finer sands attests marked predepositional eolian activity. Composition of quartz, fresh and partly weathered K-feldspar, micas, and stable heavy minerals is inferred to reflect a prolonged predepositional history during which unstable minerals were destroyed. Hematitization of biotite flakes, and other diagenetic modifications, are inferred to result from pedogenesis in an alluvial environment of deposition.

scholarly journals THE IMPACT OF SEASONAL CHANGES ON HEAVY MINERALS CONCENTRATION FROM A PART OF EAST COAST OF INDIA

2020 ◽  
Vol 5 (1) ◽  
pp. 12-21
Author(s):  
Ali Mohammad ◽  
E.N. Dhanamjayarao
Keyword(s):  
Seasonal Changes ◽  
East Coast ◽  
Heavy Mineral ◽  
Heavy Minerals ◽  
Sediment Characteristics ◽  
Seasonal Fluctuations ◽  
Post Monsoon ◽  
Seasonal Circulation ◽  
Mineral Concentrations ◽  
The Impact

Pre and post monsoonal changes in the environment have led to a noticeable variation in sediment characteristics, heavy mineral concentrations and their distribution. The current study aimed to find out the effect of seasonal fluctuations on the concentration of heavy minerals along the coast and the variations in sediment textures and distribution. The study has revealed the effect of seasons on the sediments supply and its distribution along coast in the study area. The total heavy minerals concentrations are more in post monsoon than in pre monsoon and the concentration also increases from south to north in parts of the study area because of seasonal circulation of currents from south to north along the shore. The micro textural study of the heavy mineral grains from different locations in the study area revealed the mechanical and chemical erosions on the grain surfaces.

Quaternary sedimentation and marine placers along the North Shore, Gulf of St. Lawrence

1993 ◽  
Vol 30 (3) ◽  
pp. 553-574 ◽  
Author(s):  
Frances J. Hein ◽  
James P. M. Syvitski ◽  
Lynda A. Dredge ◽  
Bernard F. Long
Keyword(s):  
Current System ◽  
Heavy Mineral ◽  
Heavy Minerals ◽  
Coarse Grained ◽  
Mineral Concentration ◽  
Lawrence Estuary ◽  
North Shore ◽  
The North ◽  
Late Wisconsinan ◽  
Mineral Concentrations

Offshore areas, along the North Shore of the St. Lawrence Estuary, have major lithostratigraphic and seismostratigraphic units that relate to the advance or retreat of the Late Wisconsinan Ice Sheet, subsequent marine transgression or regression, and reworking of postglacial deposits. Glacial diamicton and glaciomarine units (acoustic units 1 and 2) were emplaced between >18 and 14.5 ka, by basal meltout or ice-marginal sedimentation; they reflect ice-proximal sedimentation associated with ice-terminal stillstands. Deep-water muds (acoustic unit 3) represent ice-distal accumulation of glaciomarine sediment from glaciofluvial plumes between 13.5 and 11 ka. After this time exceptionally thick nearshore coarse-grained deltaic and estuarine successions (acoustic unit 4) were deposited. The uppermost postglacial sediment (acoustic unit 5) forms the seabed and reflects a reworking phase concomitant with a lowering sea level and ablating Late Wisconsinan ice sheets.Glacioisostatic rebound, which occurred about 23 ka to the present, uplifted glacial and marine deposits and resulted in extensive reworking and production of modern placers. Heavy-mineral concentrations vary as follows: terrestrial tills, 9–20%; modem storm-berm and delta top deposits, 43–60%; delta slope deposits, 25–55%; and deep (170+ m) offshore sediments, 0–2%. Three stages occurred in marine placer formation: (1) 6700 BP, fluvial discharge was high, and fluvial-dominated deltas were built; marine limit was 30 m asl, with progradation of deltas and delivery of sediments with at most 2% heavy minerals; (2) 5200 BP, fluvial discharge was reduced; marine limit was 15 m asl, deltaic sediments were reworked, increasing heavy mineral concentration to 2–8%; (3) 2800 BP, fluvial input was greatly reduced, waves and tides were more influential, a strong littoral current system developed, causing significant reworking of nearshore sediments, heavy mineral concentrations increased, with values exceeding 20% locally. Mass budget calculations show that the second-cycle reworked sediment (acoustic unit 5) is a potential economic target (1 km3, or 1700 Mt). If 7% (using atomic weights) of this target sediment is ilmenite (FeTiO3). then 27 Mt of titanium may be available.

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.

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 Heavy minerals in the Wajid Sandstone from Abha-Khamis Mushayt area, southwestern Saudi Arabia: implications on provenance and regional tectonic setting

GeoArabia ◽  
2004 ◽  
Vol 9 (4) ◽  
pp. 77-102 ◽  
Author(s):  
Mahbub Hussain ◽  
Lameed O. Babalola ◽  
Mustafa M. Hariri
Keyword(s):  
Saudi Arabia ◽  
Tectonic Setting ◽  
Principal Component ◽  
Heavy Mineral ◽  
Heavy Minerals ◽  
Coarse Grained ◽  
Distribution Data ◽  
The South ◽  
Quartz Content ◽  
The North

ABSTRACT The Wajid Sandstone (Ordovician-Permian) as exposed along the road-cut sections of the Abha and Khamis Mushayt areas in southwestern Saudi Arabia, is a mediun to coarse-grained, mineralogically mature quartz arenite with an average quartz content of over 95%. Monocrystalline quartz is the dominant framework grain followed by polycrystalline quartz, feldspar and micas. The non-opaque heavy mineral assemblage of the sandstone is dominated by zircon, tourmaline and rutile (ZTR). Additional heavy minerals, constituting a very minor fraction of the heavies, include epidote, hornblende, and kyanite. Statistical analysis showed significant correlations between zircon, tourmaline, rutile, epidote and hornblende. Principal component R-mode varimax factor analysis of the heavy mineral distribution data shows two strong associations: (1) tourmaline, zircon, rutile, and (2) epidote and hornblende suggesting several likely provenances including igneous, recycled sedimentary and metamorphic rocks. However, an abundance of the ZTR minerals favors a recycled sedimentary source over other possibilities. Mineralogical maturity coupled with characteristic heavy mineral associations, consistent north-directed paleoflow evidence, and the tectonic evolutionary history of the region indicate a provenance south of the study area. The most likely provenances of the lower part (Dibsiyah and Khusayyan members) of the Wajid Sandstone are the Neoproterozoic Afif, Abas, Al-Bayda, Al-Mahfid, and Al-Mukalla terranes, and older recycled sediments of the infra-Cambrian Ghabar Group in Yemen to the south. Because Neoproterozic (650-542 Ma) rocks are not widespread in Somalia, Eritrea and Ethiopia, a significant source further to the south is not likely. The dominance of the ultrastable minerals zircon, tourmaline and rutile and apparent absence of metastable, labile minerals in the heavy mineral suite preclude the exposed arc-derived oceanic terrains of the Arabian Shield in the west and north as a significant contributor of the sandstone. An abundance of finer-grained siliciclastic sequences of the same age in the north, is consistent with a northerly transport direction and the existence of a deeper basin (Tabuk Basin?) to the north. The tectonic and depositional model presented in this paper differs from the existing model that envisages sediment transportation and gradual basin filling from west to east during the Paleozoic.

Stability of detrital heavy minerals in Tertiary sandstones from the North Sea Basin

Clay Minerals ◽  
1984 ◽  
Vol 19 (3) ◽  
pp. 287-308 ◽  
Author(s):  
A. C. Morton
Keyword(s):  
North Sea ◽  
Mineral Dissolution ◽  
Heavy Mineral ◽  
Heavy Minerals ◽  
Fluid Temperature ◽  
The North ◽  
Deep Burial ◽  
Mineral Stability ◽  
History Of ◽  
Temperature Rate

AbstractIntrastratal solution of detrital heavy minerals in North Sea Tertiary sandstones takes place in two different diagenetic settings, deep burial and acidic weathering. These are characterized by different orders of mineral stability: apatite, chloritoid, garnet, sphene and spinel are less stable in acidic weathering than in deep burial, whereas the reverse is true for andalusite, kyanite and sillimanite. Heavy-mineral dissolution patterns, therefore, do not follow one single order of stability but several, depending on the diagenetic environment in which the dissolution occurs. It seems from this that the relative order of stability for detrital heavy minerals is controlled by the chemistry of the interstitial waters, whereas the limits of persistence depend on pore-fluid temperature, rate of water throughput, and geological age. Because different diagenetic environments lead to differing orders of mineral stability, it may prove possible to elucidate certain aspects of the diagenetic history of a sandstone by heavy-mineral dissolution patterns.

Geochemical and mineralogical characteristics of beach sand sediments in southwestern Black Sea: An approach to heavy mineral placers

2020 ◽  
Author(s):  
Hatice Nur Bayram ◽  
Asli Nur Uslu ◽  
Ali Erdem Bakkalbasi ◽  
Demet Kiran Yildirim ◽  
Zeynep Doner ◽  
...  
Keyword(s):  
Black Sea ◽  
Heavy Mineral ◽  
Source Rocks ◽  
Heavy Minerals ◽  
Beach Sand ◽  
Minor Amount ◽  
X Ray ◽  
Mineralogical Characteristics ◽  
Beach Sands ◽  
Sand Sediments

<p><strong>Geochemical and mineralogical characteristics of beach sand sediments in southwestern Black Sea: An approach to heavy mineral placers  </strong></p><p><strong> </strong><strong>Hatice Nur Bayram (1*), Aslı Nur Uslu (1), Ali Erdem Bakkalbaşı (1), Demet Kiran Yildirim (1), </strong><strong>Zeynep Doner (1), Ali Tugcan Unluer (1)</strong></p><p><strong> </strong>(1) Istanbul Technical University, Faculty of Mines, Department of Geological Engineering, Istanbul, Turkey (*[email protected])</p><p><strong>Abstract: </strong><strong> </strong></p><p>Coastal or beach placer deposits are enrichments of heavy minerals with significant metal content that have been mechanically formed. This work studies the geochemical and mineralogical characteristics of beach sand sediments of southwestern Black Sea, Turkey which cover approximately 20 km<sup>2</sup> area. The study area has 4 main geological units: Upper Cretaceous moderately-K kalkalkaline Istanbul volcanics, Oligocene Danismen Formation which is dominated by flood plain, marshy and lake environments, Upper Miocene-Pliocene Belgrad Formation which is dominated by terrestrial deposits, mostly gravel, sand and clay dominated and Quaternary formations which include sandy beaches, sand dunes and river alluvials.</p><p>A total of 8 beach sand samples were analyzed by X-ray Diffraction (XRD) and X-ray Fluorecance (XRF). Mineralogical compositions are mainly dominated by quartz, siderite, albite, calcite and minor amount of magnetite. Siderite-rich beach sands are observed in western part of the study area and mostly derived from Danismen Formation. Fe<sub>2</sub>O<sub>3</sub> contents of this area are determined up to 40%.  On the other hand, in eastern part of the study area REE-Th-U content of beach sands are relatively higher than source rocks which is defined as a high-Al moderately-K kalkalkaline felsic rocks. The highest HFSE concentration were determined in -250+125µm fraction which consists of 16.5% of eastern beach sand. In this fraction LREE-Zr-U content rise drastically. It can be considered that REE-LREE contents is related with monazite minerals and U contents is related with zircon minerals, considering the monazite and zircon minerals are resistant to weathering and likely to occur in the orthomagmatic phase in the source volcanics.</p><p><strong>Key words</strong>: Beach sand sediments; REE-Th-U; heavy minerals; southwestern of Black Sea; Turkey</p>

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.

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