Helvine-group minerals from Norwegian granitic pegmatites and some other granitic rocks: Cases of significant Sc and Sn contents

2020 ◽  
Vol 58 (3) ◽  
pp. 367-379
Author(s):  
Gunnar Raade
Keyword(s):  
Continuous Solid Solution ◽  
Granitic Rocks ◽  
Metamorphic Overprint ◽  
Northern Norway ◽  
Granitic Pegmatites ◽  
Minor Elements ◽  
Southern Norway ◽  
Nearly Continuous ◽  
Miarolitic Cavities ◽  
Oscillatory Zonation

ABSTRACT Helvine-group minerals from two granitic pegmatites have disparate compositions, from nearly pure helvine (Ågskardet, northern Norway; Devonian) to helvine close to ternary compositions (Heftetjern, southern Norway; Precambrian). Metagranite from Høgtuva (northern Norway; Precambrian with Caledonian metamorphic overprint) contains Zn-rich danalite. The Ågskardet helvine contains up to 0.46 wt.% SnO2, and the Heftetjern ternary helvine shows a maximum of 1.74 wt.% Sc2O3. Helvine minerals were also analyzed from three occurrences connected to peralkaline granite (ekerite) of the Permian Oslo Rift. Nearly pure genthelvite (99.19 mol.%) occurs in miarolitic cavities at Gjerdingselva. Two mineralogically different granitic pegmatites derived from the same ekerite pluton in the southern part of the Oslo Rift show quite distinct helvine compositions, from nearly continuous solid solution between helvine and genthelvite in crystals with oscillatory zonation (Rundemyr) to solid solutions midway between danalite and genthelvite (Bakstevalåsen). The Rundemyr crystals have a maximum SnO2 content of 1.28 wt.%. The incorporation of minor elements (Ca, Mg, Al, Sn, Sc) in helvine-group minerals is discussed with emphasis on their chalcophilicity characteristics. For stereochemical reasons, Sn in helvine minerals must be tetravalent, even if Sn2+ is more chalcophile than Sn4+.

scholarly journals Sensitivities of glacier mass balance and runoff to climate perturbations in Norway

2015 ◽  
Vol 56 (70) ◽  
pp. 79-88 ◽  
Author(s):  
Markus Engelhardt ◽  
Thomas V. Schuler ◽  
Liss M. Andreassen
Keyword(s):  
Mass Balance ◽  
Temperature Change ◽  
Air Temperature ◽  
Annual Runoff ◽  
Precipitation Change ◽  
Glacier Mass Balance ◽  
Northern Norway ◽  
Temperature Range ◽  
Temperature And Precipitation ◽  
Southern Norway

AbstractThis study evaluates sensitivities of glacier mass balance and runoff to both annual and monthly perturbations in air temperature and precipitation at four highly glacierized catchments: Engabreen in northern Norway and Ålfotbreen, Nigardsbreen and Storbreen, which are aligned along a west–east profile in southern Norway. The glacier mass-balance sensitivities to changes in annual air temperature range from 1.74 m w.e. K−1 for Ålfotbreen to 0.55 m w.e. K−1 for Storbreen, the most maritime and the most continental glaciers in this study, respectively. The runoff sensitivities of all catchments are 20–25% per degree temperature change and 6–18% for a 30% precipitation change. A seasonality of the sensitivities becomes apparent. With increasing continentality, the sensitivity of mass balance and runoff to temperature perturbations during summer increases, and the sensitivity of annual runoff to both temperature and precipitation perturbations is constricted towards changes during the ablation period. Comparing sensitivities in northern and southern Norway, as well as the variability across southern Norway, reveals that continentality influences sensitivities more than latitude does.

scholarly journals The Chemistry of Quartz in Granitic Pegmatites of Southern Norway: Petrogenetic and Economic Implications

2015 ◽  
Vol 110 (7) ◽  
pp. 1737-1757 ◽  
Author(s):  
Axel Müller ◽  
Peter M. Ihlen ◽  
Ben Snook ◽  
Rune Berg Larsen ◽  
Belinda Flem ◽  
...  
Keyword(s):  
Economic Implications ◽  
Granitic Pegmatites ◽  
Southern Norway

The term farsundite

1968 ◽  
Vol 105 (4) ◽  
pp. 387-389
Author(s):  
Eric Middlemost
Keyword(s):  
Type Locality ◽  
Granitic Rocks ◽  
Southern Norway

SUMMARYFarsundite from the type locality in southern Norway is described. The use and abuse of the term is discussed. It is recommended that the term should be restricted to use as a local specific name for the granitic rocks of the Farsund area.

scholarly journals Determinants of trip duration for international tourists in Norway; a parametric survival analysis

2017 ◽  
Vol 8 (1) ◽  
pp. 75-86
Author(s):  
Tannaz Alizadeh Ashrafi ◽  
Øystein Myrland
Keyword(s):  
Survival Probability ◽  
Geographical Area ◽  
Road Transport ◽  
Northern Norway ◽  
Trip Purpose ◽  
Cox Proportional Hazard ◽  
Parametric Survival Model ◽  
Southern Norway ◽  
Travel Type ◽  
Parametric Survival

AbstractHow long a tourist stays in a host country acts as an indicator of tourism industry’s contribution towards the national economy. The purpose of this study is to examine how socio-demographic characteristics of international tourists, their travelling purpose, tourism products and characteristics of the destination influence the length of stay in Norway, by estimating a parametric survival model. Total cost of trip, purpose of travel, type of accommodation and transportation, age of tourist and geographical area are key elements that explain the variation in the length of tourist stay in Norway. The Cox proportional hazard model with time-independent covariates indicates the survival probability of tourists with less budget constraints and younger ages is higher than that of low-spending tourists and elderly travelers. Moreover, tourists with the purpose of friend and family visitation are at lower risk of leaving Norway than are tourists with other purposes. In terms of tourism products, choosing camping sites as the type of accommodation and road transport as the mode of transportation are associated with the highest survival probability. Another key finding is that tourists stay longer in northern Norway than in southern Norway; hence, on average, tourists’ overall expenditures are higher in northern Norway.

Month of birth as a latitude-dependent risk factor for multiple sclerosis in Norway

2012 ◽  
Vol 19 (8) ◽  
pp. 1028-1034 ◽  
Author(s):  
Nina Grytten ◽  
Øivind Torkildsen ◽  
Jan Harald Aarseth ◽  
Espen Benjaminsen ◽  
Elisabeth Gulowsen Celius ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Vitamin D ◽  
Latitudinal Gradient ◽  
Month Of Birth ◽  
Northern Norway ◽  
Prevalence Studies ◽  
Exposure During Pregnancy ◽  
Uv Dose ◽  
Southern Norway

Objective: We aimed to determine if the risk of Multiple Sclerosis (MS) is associated with month of birth in Norway and to explore a possible latitudinal gradient. Methods: All patients with MS born between 1930 and 1979 registered in the Norwegian MS Registry or ascertained in Norwegian prevalence studies were included ( n = 6649). The latitude gradient was divided in Southern, Middle and Northern Norway, according to the estimated regional yearly mean vitamin D effective UV dose. Results: Risk of MS was 11% higher for those born in April ( p = 0.045), and 5% higher for those born in May ( p = 0.229), 5% lower for those born in November ( p = 0.302) and 12% lower for those born in February ( p = 0.053) compared with the corresponding population, unaffected mothers and siblings. In Southern Norway the odds ratio of MS births in April and May was 1.05 (0.98 – 1.24), in Middle Norway 1.11 (0.97 – 1.27) and in Northern Norway 1.28 (1.0 – 1.63) compared with the other months. Conclusions: This study confirms previous reports of increased MS births in spring and decreased MS births in the winter months. This could support the role of decreased sunlight exposure during pregnancy and vitamin D deficiency in prenatal life in MS.

scholarly journals Permafrost distribution in steep rock slopes in Norway: measurements, statistical modelling and implications for geomorphological processes

2019 ◽  
Vol 7 (4) ◽  
pp. 1019-1040 ◽  
Author(s):  
Florence Magnin ◽  
Bernd Etzelmüller ◽  
Sebastian Westermann ◽  
Ketil Isaksen ◽  
Paula Hilger ◽  
...  
Keyword(s):  
Rock Slope ◽  
Multiple Linear Regression Model ◽  
Permafrost Degradation ◽  
Rock Slopes ◽  
Northern Norway ◽  
Precise Knowledge ◽  
Discontinuous Permafrost ◽  
Southern Norway ◽  
Steep Slopes ◽  
North And South

Abstract. Permafrost in steep rock slopes has been increasingly studied since the early 2000s in conjunction with a growing number of rock slope failures, which likely resulted from permafrost degradation. In Norway, rock slope destabilization is a widespread phenomenon and a major source of risk for the population and infrastructure. However, a lack of precise knowledge of the permafrost distribution in steep slopes hinders the assessment of its role in these destabilizations. This study proposes the first nationwide permafrost probability map for the steep slopes of Norway (CryoWall map). It is based on a multiple linear regression model fitted with multi-annual rock surface temperature (RST) measurements, collected at 25 rock slope sites, spread across a latitudinal transect (59–69∘ N) over mainland Norway. The CryoWall map suggests that discontinuous permafrost widely occurs above 1300–1400 and 1600–1700 m a.s.l. in the north and south rock faces of southern Norway (59∘ N), respectively. This lower altitudinal limit decreases in northern Norway (70∘ N) by about 500±50 m, with a more pronounced decrease for south faces, as a result of the insolation patterns largely driven by midnight sun in summer and polar night in winter. Similarly, the mean annual RST differences between north and south faces of similar elevation range around 1.5 ∘C in northern Norway and 3.5 ∘C in southern Norway. The CryoWall map is evaluated against direct ice observations in steep slopes and discussed in the context of former permafrost studies in various types of terrain in Norway. We show that permafrost can occur at much lower elevations in steep rock slopes than in other terrains, especially in north faces. We demonstrate that the CryoWall map is a valuable basis for further investigations related to permafrost in steep slopes in terms of both practical concerns and fundamental science.

TBE in Norway

2021 ◽  
Author(s):  
Katrine M. Paulsen ◽  
Rose Vikse ◽  
Arnulf Soleng ◽  
Kristin Edgar ◽  
Heidi Elisabeth Heggen Lindstedt ◽  
...  
Keyword(s):  
Surveillance System ◽  
Communicable Diseases ◽  
Coastal Areas ◽  
Notifiable Disease ◽  
Northern Norway ◽  
Tick Borne Encephalitis ◽  
Southern Norway

In Norway, tick-borne encephalitis (TBE) has been a mandatory notifiable disease since 1975 (Norwegian Surveillance system for communicable diseases, MSIS).1 According to ECDCs classification, coastal areas in southern Norway (counties of Agder, and Vestfold and Telemark) are endemic for TBE. Further, Viken County (former Østfold, Akershus and Buskerud), and western and northern Norway to Brønnøy municipality is imperiled.2-9

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