Recalibrating Rodinian rifting in the northwestern United States

Geology ◽  
2021 ◽  
Author(s):  
Daniel T. Brennan ◽  
Zheng-Xiang Li ◽  
Kai Rankenburg ◽  
Noreen Evans ◽  
Paul K. Link ◽  
...  
Keyword(s):  
United States ◽  
Magmatic Rocks ◽  
Zircon Crystallization ◽  
Depositional Age ◽  
A Minor ◽  
First Time ◽  
Age Constraints ◽  
Early Phases ◽  
Buffalo Hump ◽  
Conventional Laser

A lack of precise age constraints for Neoproterozoic strata in the northwestern United States (Washington State), including the Buffalo Hump Formation (BHF), has resulted in conflicting interpretations of Rodinia amalgamation and breakup processes. Previous detrital zircon (DZ) studies identified a youngest ca. 1.1 Ga DZ age population in the BHF, interpreted to reflect mostly first-cycle sourcing of unidentified but proximal magmatic rocks intruded during the amalgamation of Rodinia at ca. 1.0 Ga. Alternatively, the ca. 1.1 Ga DZ population has been suggested to represent a distal source with deposition occurring during the early phases of Rodinia rifting, more than 250 m.y. after zircon crystallization. We combined conventional laser-ablation split-stream analyses of U-Pb/Lu-Hf isotopes in zircon with a method of rapid (8 s per spot) U-Pb analysis to evaluate these opposing models. Our study of ~2000 DZ grains from the BHF identified for the first time a minor (~1%) yet significant ca. 760 Ma population, which constrains the maximum depositional age. This new geochronology implies that the BHF records early rift deposition during the breakup of Rodinia and correlates with sedimentary rocks found in other late Tonian basins of southwestern Laurentia.

Age constraints for Paleoproterozoic glaciation in the Lake Superior Region: detrital zircon and hydrothermal xenotime ages for the Chocolay Group, Marquette Range Supergroup

2006 ◽  
Vol 43 (5) ◽  
pp. 571-591 ◽  
Author(s):  
Daniela A Vallini ◽  
William F Cannon ◽  
Klaus J Schulz
Keyword(s):  
Detrital Zircon ◽  
Sedimentary Cover ◽  
Lake Superior ◽  
The North ◽  
Lake Formation ◽  
Geochronological Study ◽  
Minimum Age ◽  
Depositional Age ◽  
First Time ◽  
Age Constraints

A geochronological study of the Chocolay Group at the base of the Paleoproterozoic Marquette Range Supergroup in Michigan, Lake Superior Region, is attempted for the first time. Age data from detrital zircon grains and hydrothermal xenotime from the basal glaciogenic formation, the Enchantment Lake Formation, and the stratigraphically higher Sturgeon Quartzite and its equivalent, the Sunday Quartzite, provide maximum and minimum age constraints for the Chocolay Group. The youngest detrital zircon population in the Enchantment Lake Formation is 2317 ± 6 Ma; in the Sturgeon Quartzite, it is 2306 ± 9 Ma, and in the Sunday Quartzite, it is 2647 ± 5 Ma. The oldest hydrothermal xenotime age in the Enchantment Lake Formation is 2133 ± 11 Ma; in the Sturgeon Quartzite, it is 2115 ± 5 Ma, and in the Sunday Quartzite, it is 2207 ± 5 Ma. The radiometric age data in this study implies the depositional age of the Chocolay Group is constrained to ~2.3–2.2 Ga, which proves its correlation with part of the Huronian Supergroup in the Lake Huron Region, Ontario, and reveals the unconformity that separates the Chocolay Group from the overlying Menominee Group is up to 325 million years in duration. The source(s) of the ~ 2.3 Ga detrital zircon populations in the Enchantment Lake Formation and Sturgeon Quartzite remains an enigma because no known rock units of this age are known in the Michigan area. It is speculated that once widespread volcano-sedimentary cover sequences in Michigan were removed or concealed prior to Chocolay Group deposition. The hydrothermal xenotime ages probably reflect basinal hydrothermal fluid flow associated with the period of extension, involving rifting and major dyke formation, that affected the North American provinces between 2.2 and 2.1 Ga.

scholarly journals Supplemental Material: Recalibrating Rodinian rifting in the northwestern United States

2021 ◽  
Author(s):  
Daniel Brennan ◽  
et al.
Keyword(s):  
United States ◽  
Mass Spectrometry ◽  
Detrital Zircon ◽  
Inductively Coupled Plasma ◽  
Individual Sample ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Plasma Mass Spectrometry ◽  
Depositional Age ◽  
Conventional Laser

Individual sample detrital zircon results, alternative maximum depositional age calculations, conventional laser-ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) methodology, rapid LA-ICP-MS methodology, sample locations, and detrital zircon U-Pb/Lu-Hf results for all analyses and compiled U-Pb data.<br>

scholarly journals Supplemental Material: Recalibrating Rodinian rifting in the northwestern United States

2021 ◽  
Author(s):  
Daniel Brennan ◽  
et al.
Keyword(s):  
United States ◽  
Mass Spectrometry ◽  
Detrital Zircon ◽  
Inductively Coupled Plasma ◽  
Individual Sample ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Plasma Mass Spectrometry ◽  
Depositional Age ◽  
Conventional Laser

Individual sample detrital zircon results, alternative maximum depositional age calculations, conventional laser-ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) methodology, rapid LA-ICP-MS methodology, sample locations, and detrital zircon U-Pb/Lu-Hf results for all analyses and compiled U-Pb data.<br>

Livre Jubilaire du Conseil D'Etat

1953 ◽  
Vol 11 (3) ◽  
pp. 425-434
Author(s):  
C. J. Hamson
Keyword(s):  
United States ◽  
French Revolution ◽  
The United States ◽  
Administrative Law ◽  
French History ◽  
The Public ◽  
The United Kingdom ◽  
A Minor ◽  
First Time ◽  
Unequal Length

This imposing quarto volume is offered to the public as a permanent memorial of the 150th anniversary of the Conseil d'Etat. It is a remarkable book, not unworthy of the very remarkable institution which it seeks to portray.Although the Conseil, as the Conseil du Roi, goes back a very long way in French history, it suffered an interruption at the French Revolution. The interruption proved indeed to be a minor one, lasting nine years only. Nevertheless, the Conseil was in some sense reformed by Napoleon under the Constitution du 22 Frimaire; and as the Conseil d'Etat it met for the first time on Christmas Day 1799 (a day then disguised as 4 Nivose An VIII) under conditions of no small informality. It is its first meeting under Napoleon which has been selected as the new terminus a quo of an institution in reality a great deal older.The book consists of some 50 articles (of very unequal length, one of them being an extensive monograph) and is divided into two parts. The second, shorter, part (though of over 200 pages) consists of contributions by persons who are not French and is concerned mainly with the influence of the Conseil d'Etat outside France, though it also includes articles on administrative questions in the United Kingdom (by Prof. W. A. Robson) in the United States, and in Canada (by the Chief Justice of Canada). It is proposed in this review wholly to neglect this part, however great its interest, principally because the English reader will find greater profit in the account given of the functioning in France of the authentic, the French, Conseil d'Etat: which may fairly be called the creator of the only system of administrative law properly meriting that title.

scholarly journals Supplemental Material: Recalibrating Rodinian rifting in the northwestern United States

2021 ◽  
Author(s):  
Daniel Brennan ◽  
et al.
Keyword(s):  
United States ◽  
Mass Spectrometry ◽  
Detrital Zircon ◽  
Inductively Coupled Plasma ◽  
Individual Sample ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Plasma Mass Spectrometry ◽  
Depositional Age ◽  
Conventional Laser

Individual sample detrital zircon results, alternative maximum depositional age calculations, conventional laser-ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) methodology, rapid LA-ICP-MS methodology, sample locations, and detrital zircon U-Pb/Lu-Hf results for all analyses and compiled U-Pb data.<br>

scholarly journals Supplemental Material: Recalibrating Rodinian rifting in the northwestern United States

2021 ◽  
Author(s):  
Daniel Brennan ◽  
et al.
Keyword(s):  
United States ◽  
Mass Spectrometry ◽  
Detrital Zircon ◽  
Inductively Coupled Plasma ◽  
Individual Sample ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Plasma Mass Spectrometry ◽  
Depositional Age ◽  
Conventional Laser

Individual sample detrital zircon results, alternative maximum depositional age calculations, conventional laser-ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) methodology, rapid LA-ICP-MS methodology, sample locations, and detrital zircon U-Pb/Lu-Hf results for all analyses and compiled U-Pb data.<br>

The End of Empire and the Search for Justice

2018 ◽  
Author(s):  
John Linarelli ◽  
Margot E Salomon ◽  
Muthucumaraswamy Sornarajah
Keyword(s):  
United States ◽  
International Economic ◽  
International Law ◽  
International Economic Order ◽  
The United States ◽  
Economic Order ◽  
Global Context ◽  
Neoliberal Ideology ◽  
First Time

This chapter is a study of the themes of the New International Economic Order (NIEO). It begins with the notion of justice that had been constructed in imperial law to justify empire and colonialism. The NIEO was the first time a prescription was made for justice in a global context not based on domination of one people over another. In its consideration of the emergence of a new notion of justice in international law, the chapter discusses the reasons for the origins of the NIEO, and goes on to describe the principles of the NIEO and the extent to which they came into conflict with dominant international law as accepted by the United States and European states. Next the chapter deals with the rise of the neoliberal ideology that led to the displacement of the NIEO and examines the issue of whether the NIEO and its ideals have passed or whether they continue to be or should be influential in international law. Finally, the chapter turns to the ideas of the NIEO alongside new efforts at promoting a fuller account of justice by which to justify and evaluate international law.

Sources of Information About Gestational Weight Gain, Diet, and Exercise Among Brazilian Immigrant Women Living in the United States: A Cross-Sectional Study

2021 ◽  
pp. 1-41
Author(s):  
Ana Cristina Lindsay ◽  
Qun Le ◽  
Denise Lima Nogueira ◽  
Márcia M. T. Machado ◽  
Mary L. Greaney
Keyword(s):  
United States ◽  
Weight Gain ◽  
Gestational Weight Gain ◽  
The United States ◽  
The Internet ◽  
Sources Of Information ◽  
Cross Sectional ◽  
Gestational Weight ◽  
Diet And Exercise ◽  
First Time

Abstract Objectives: The objective of this study was to assess sources of information about gestational weight gain (GWG), diet, and exercise among first-time pregnant Brazilian women in the United States (US). Design: Cross-sectional survey. Setting: Massachusetts, United States. Participants: First-time pregnant Brazilian women. Results: Eighty-six women, the majority of whom were immigrants (96.5%) classified as having low-acculturation levels (68%), participated in the study. Approximately two-thirds of respondents had sought information about GWG (72.1%), diet (79.1%), and exercise (74.4%) via the internet. Women classified as having low acculturation levels were more likely to seek information about GWG via the internet (OR = 7.55; 95% CI: 1.41, 40.26) than those with high acculturation levels after adjusting for age and receiving information about GWG from healthcare provider (doctor or midwife). Moreover, many respondents reported seeking information about GWG (67%), diet (71%), and exercise (52%) from family and friends. Women who self-identified as being overweight pre-pregnancy were less likely to seek information about diet (OR = 0.32; 95% CI: 0.11, 0.93) and exercise (OR = 0.33; 95% CI: 0.11, 0.96) from family and friends than those who self-identified being normal weight pre-pregnancy. Conclusions: This is the first study to assess sources of information about GWG, diet, and exercise among pregnant Brazilian immigrants in the US. Findings have implications for the design of interventions and suggest the potential of mHealth intervention as low-cost, easy access option for delivering culturally and linguistically tailored evidence-based information about GWG incorporating behavioral change practices to this growing immigrant group.

scholarly journals First Report of Wisteria vein mosaic virus in Wisteria sinensis in the United States of America

2008 ◽  
Vol 9 (1) ◽  
pp. 42 ◽  
Author(s):  
Rayapati A. Naidu ◽  
Gandhi Karthikeyan
Keyword(s):  
United States ◽  
Mosaic Virus ◽  
United States Of America ◽  
The United States ◽  
Home Gardens ◽  
First Report ◽  
Woody Perennial ◽  
Wisteria Sinensis ◽  
First Time ◽  
Wisteria Vein Mosaic Virus

The ornamental Chinese wisteria (Wisteria sinensis) is a woody perennial grown for its flowering habit in home gardens and landscape settings. In this brief, the occurrence of Wisteria vein mosaic virus (WVMV) was reported for the first time in Chinese wisteria in the United States of America. Accepted for publication 18 June 2008. Published 18 August 2008.

Wartime Prosperity? A Reassessment of the U.S. Economy in the 1940s

1992 ◽  
Vol 52 (1) ◽  
pp. 41-60 ◽  
Author(s):  
Robert Higgs
Keyword(s):  
United States ◽  
World War Ii ◽  
Performance Measures ◽  
Well Being ◽  
The United States ◽  
World War ◽  
Macroeconomic Performance ◽  
Command Economy ◽  
First Time ◽  
The U.S

Relying on standard measures of macroeconomic performance, historians and economists believe that “war prosperity” prevailed in the United States during World War II. This belief is ill-founded, because it does not recognize that the United States had a command economy during the war. From 1942 to 1946 some macroeconomic performance measures are statistically inaccurate; others are conceptually inappropriate. A better grounded interpretation is that during the war the economy was a huge arsenal in which the well-being of consumers deteriorated. After the war genuine prosperity returned for the first time since 1929.

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