The Paleomagnetism of Diabase Dikes from the Grenville Province

A paleomagnetic study was attempted of the diabase dike swarm intruding the Grenville structural province of the Canadian Shield. Both the alternating field and thermal demagnetization studies indicated that the dikes have varying degrees of stability of magnetization. Some dikes were shown to have stable primary component of magnetization. Microscopic observations indicated that, in most cases, the primary magnetic mineral titanomagnetite was altered to titanomaghemite, probably due to low temperature oxidation. A good correlation is obtained between magnetic stability and relative abundance of titanomagnetite to titanomaghemite in that dike. The mean paleomagnetic pole for the Grenville dike swarm, which is probably of late Precambrian age, was computed to lie at 3.0° N, 29.0° W with A25 = 11.0°. Comparison of this result with other Precambrian pole positions of similar age relative to North America suggests that the dikes were intruded after the Grenville orogeny.

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Paleomagnetic study of lower Mesozoic diabase dikes and sills of Connecticut and Maryland

Canadian Journal of Earth Sciences ◽

10.1139/e76-063 ◽

1976 ◽

Vol 13 (4) ◽

pp. 597-609 ◽

Cited By ~ 11

Author(s):

Timothy E. Smith

Keyword(s):

Middle Jurassic ◽

Pole Position ◽

Low Temperature Oxidation ◽

Temperature Oxidation ◽

Sea Floor ◽

Good Convergence ◽

Faunal Assemblages ◽

Paleomagnetic Study ◽

Intrusive Rocks ◽

Stratigraphic Position

Paleomagnetic results from 61 sites on diabase dikes and sills in Connecticut and Maryland yield a mean pole of position of 100.9 °E. 68.6 °N, α95 = 1.6°. These results combined with those from 7S sites on four diabase sills in the Gettysburg Basin of Pennsylvania produce a mean pole position of 101, 6 °E. 65.4 °N, α95 = 1.3 °from 139 VGPs. These rocks arc probably of Early to early Middle Jurassic age by stratigraphic and inferred stratigraphic position. The paleomagnetic results indicate that the Gettysburg and Hartford Basins did not subside simultaneously.The dispersion of virtual geomagnetic poles about the mean pole of the Connecticut, Pennsylvania, and Maryland intrusive rocks is probably the result of 'homogenization' of magnetic directions during low-temperature oxidation of titanomagnetite to titanomaghemite over a period long enough to erase a considerable amount of dispersion due to secular variation.Rotation of Europe against North America in the prerifting configuration causes good convergence of European Jurassic mean poles and the pole of the Connecticut. Maryland, and Pennsylvania intrusive rocks. This is evidence that separation of the two continents had not begun by Early to early Middle Jurassic time, which is in agreement with earlier findings based on sea-floor magnetic anomalies and faunal assemblages.

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Paleomagnetism of Steel Mountain and Indian Head anorthosites from western Newfoundland

Canadian Journal of Earth Sciences ◽

10.1139/e76-007 ◽

1976 ◽

Vol 13 (1) ◽

pp. 75-83 ◽

Cited By ~ 24

Author(s):

G. S. Murthy ◽

K. V. Rao

Keyword(s):

Northern Hemisphere ◽

Remanent Magnetization ◽

Canadian Shield ◽

Relative Rotation ◽

Southeastern Part ◽

Lower Paleozoic ◽

Grenville Province ◽

Grenville Orogeny ◽

Paleomagnetic Pole

As part of studies of anorthosites from the northern hemisphere, the paleomagnetism of two anorthosite inliers at Indian Head and Steel Mountain in western Newfoundland is described. The six sites at Indian Head retain a stable remanent magnetization and yield a paleomagnetic pole at 8 °S, 157½° E(δp = 15°, δm = 20°). This is close to poles for anorthositic and other rock units from within the Grenville Province that represent magnetization of age 1000 m. y., suggesting that there is no relative rotation between western Newfoundland and the southeastern part of the Canadian Shield, at least since the time of the Grenville orogeny. The ten sites at Steel Mountain also retain a stable magnetization, which yields a paleomagnetic pole at 22½° S, 41 °W (δp = 8°, δm = 14°). This position is closer to lower Paleozoic poles from Newfoundland and thus probably represents a lower Paleozoic magnetization.

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Process of low-temperature oxidation of metals and alloys for reprocessing of secondary raw materials in chemical products

Technology of metals ◽

10.31044/1684-2499-2019-5-0-8-16 ◽

2019 ◽

Vol 5 ◽

pp. 8-16

Author(s):

S.D. Pozhidaeva ◽

◽

A.M. Ivanov ◽

Keyword(s):

Low Temperature ◽

Raw Materials ◽

Metals And Alloys ◽

Low Temperature Oxidation ◽

Temperature Oxidation ◽

Secondary Raw Materials ◽

Chemical Products

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Low-Temperature Oxidation Catalyst Development Supporting Homogeneous Charge Compression Ignition Development: Final Report

10.2172/1015533 ◽

2009 ◽

Author(s):

Kenneth G. Rappe ◽

Darrell R. Herling ◽

Jonathan L. Male ◽

Liyu Li ◽

Yu Su ◽

...

Keyword(s):

Low Temperature ◽

Homogeneous Charge Compression Ignition ◽

Oxidation Catalyst ◽

Final Report ◽

Compression Ignition ◽

Low Temperature Oxidation ◽

Temperature Oxidation ◽

Catalyst Development ◽

Homogeneous Charge

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Low-temperature oxidation of a gasoline surrogate: Experimental investigation in JSR and RCM using high-resolution mass spectrometry

Combustion and Flame ◽

10.1016/j.combustflame.2021.01.037 ◽

2021 ◽

Vol 228 ◽

pp. 128-141

Author(s):

Nesrine Belhadj ◽

Roland Benoit ◽

Philippe Dagaut ◽

Maxence Lailliau ◽

Bruno Moreau ◽

...

Keyword(s):

Mass Spectrometry ◽

Experimental Investigation ◽

High Resolution ◽

Low Temperature ◽

High Resolution Mass Spectrometry ◽

Low Temperature Oxidation ◽

Temperature Oxidation ◽

High Resolution Mass ◽

Resolution Mass

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Influence of Co-Precipitation Agent on the Structure, Texture and Catalytic Activity of Au-CeO2 Catalysts in Low-Temperature Oxidation of Benzyl Alcohol

Catalysts ◽

10.3390/catal11050641 ◽

2021 ◽

Vol 11 (5) ◽

pp. 641

Author(s):

Lukasz Wolski ◽

Grzegorz Nowaczyk ◽

Stefan Jurga ◽

Maria Ziolek

Keyword(s):

Gold Nanoparticles ◽

Catalytic Activity ◽

Low Temperature ◽

Benzyl Alcohol ◽

Low Temperature Oxidation ◽

Temperature Oxidation ◽

Oxidation Of Benzyl Alcohol ◽

Key Factor ◽

Au Particle Size ◽

Co Precipitation

The aim of the study was to establish the influence of a co-precipitation agent (i.e., NaOH–immediate precipitation; hexamethylenetetramine/urea–gradual precipitation and growth of nanostructures) on the properties and catalytic activity of as-synthesized Au-CeO2 nanocomposites. All catalysts were fully characterized with the use of XRD, nitrogen physisorption, ICP-OES, SEM, HR-TEM, UV-vis, XPS, and tested in low-temperature oxidation of benzyl alcohol as a model oxidation reaction. The results obtained in this study indicated that the type of co-precipitation agent has a significant impact on the growth of gold species. Immediate co-precipitation of Au-CeO2 nanostructures with the use of NaOH allowed obtainment of considerably smaller and more homogeneous in size gold nanoparticles than those formed by gradual co-precipitation and growth of Au-CeO2 nanostructures in the presence of hexamethylenetetramine or urea. In the catalytic tests, it was established that the key factor promoting high activity in low-temperature oxidation of benzyl alcohol was size of gold nanoparticles. The highest conversion of the alcohol was observed for the catalyst containing the smallest Au particle size (i.e., Au-CeO2 nanocomposite prepared with the use of NaOH as a co-precipitation agent).

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