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Characterisation of Na-metasomatism in the Sveconorwegian Bamble Sector of South norway

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Geoscience Frontiers 2014年第5期5卷 659-672页

作者： Ane K.Engvika Peter M.Ihlena Hakon Austrheimb Geological Survey of norway.P.O.box 6315 Sluppen.N-7491 TrondheimNorway department of Geosciences.university of oslo P.O.box 1047 BlindernN-0316 OsloNorway

Na-metasomatism in the form of albitisation is regionally extensive in the Precambrian crust of southern Scandinavia and is particularly widespread in the Bamble Sector, the Kongsberg-Modum Sector and the Norwegian part of the Mylonite Zone. Sites of albitisation outside these belts are associated with hy- drothermal breccia pipes and fracture-bound alteration. The albitites are composed of near end-member sodic plagioclase （Ano 5Ab94-99） with minor carbonate （calcite and dolomite）, rutile, clinopyroxene （En30Fs21-23W047 49）, amphibole （edenite-pargasite）, quartz, titanite, tourmaline, epidote （Fe3＋ - 0.20 -0.85 a.p.f.u） and chlorite （Mg# = 0.81-0.89）. The albitites have been studied in detail in the region around the town of Kragem, and are described as albitisation along veins, as breccias, alhitic felsites, massive carbonate-bearing albitites and megascale clinopyroxene-titanite-bearing albitite. The strong fluid control on their formation is illustrated by the veining and mineral replacement reactions, showing fluid transport by a H20-CO2 fluid rich in Na, depleting Fe and Mg from the host rock, in accordance with calculated mass transfer. A study of the mineralogical replacement reactions in combination with a regional compilation has demonstrated the relationship between metasomatic processes and the for- mation of apatite, ruti｜e and Fe deposits. The albitites occur spatially associated with other metasomatic rocks such as scapolitised metagabbros. We document that metasomatism is an important mineral- and rock-forming process in the continental crust, which in the Bamble Sector is a part of the tectonome- tamorphic evolution of the Sveconorwegian orogen.

关键词： AlbititeMetasomatismBamble SectorFluidsSveconorwegianSouth norway

Dehydration Melting and Proterozoic Granite Petrogenesis in a Collisional Orogen——A Case from the Svecofennian of Southern Finland

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Journal of Earth Science 2021年第6期32卷 1289-1299页

作者： Tom Andersen O.Tapani Rämö department of Geosciences University of OsloN-0316OsloNorway department of Geosciences and Geography Geology and Geophysics Research ProgramUniversity of Helsinki00014HelsinkiFinland

Dehydration melting of metasupracrustal rocks at mid-to deep-crustal levels can generate water undersaturated granitic *** this study,we evaluate the potential of~1.89–1.88 Ga metasupracrustal rocks of the Precambrian of southern Finland as source rocks for the 1.86–1.79 Ga late-orogenic leucogranites in the region,using the Rhyolite-MELTS *** close in composition to leucogranite is produced over a range of realistic pressures(5 to 8 kbar)and temperatures(800 to 850℃),at 20%–30%of partial melting,allowing separation of melt from unmelted *** solid residue is a dry,enderbitic to charnoenderbitic ganulite depleted in incompatible components,and will only yield further melt above 1000–1050℃,when rapidly increasing fractions of increasingly calcic(granodioritic to tonalitic)melts are *** solid residue after melt extraction is incapable of producing syenogranitic magmas similar to the Mid-Proterozoic,A-type rapakivi granites on further *** granitic fraction of the syenogranitic rapakivi complexes must thus have been formed by a different chain of processes,involving mantle-derived mafic melts and melts from crustal rock types not conditioned by the preceding late-orogenic Svecofennian anatexis.

关键词： leucogranite rapakivi granite anatexis restite depleted granulite Finland

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On the Importance of the Stokes-Brinkman Equations for Computing Effective Permeability in Karst Reservoirs

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Communications in Computational Physics 2011年第10期10卷 1315-1332页

作者： Marcin Krotkiewski Ingeborg S.Ligaarden Knut-Andreas Lie Daniel W.Schmid Physics of Geological Processes University of OsloP.O.Box 1048 BlindernNO-0316 OsloNorway SINTEF ICT Department of AppliedMathematicsP.O.Box 124 BlindernNO-0314 OsloNorway Center of Mathematics for Applications University of OsloP.O.Box 1053 BlindernNO-0316 OsloNorway

Cavities and fractures significantly affect the flow paths in carbonate reservoirs and should be accurately accounted for in numerical ***,we consider the problem of computing the effective permeability of rock samples based on high-resolution 3DCT scans containingmillions of *** use the Stokes-Brinkman equations in the entire domain,covering regions of free flow governed by the Stokes equations,porous Darcy flow,and transitions between *** presence of different length scales and large(ten orders of magnitude)contrasts in permeability leads to highly ill-conditioned linear systems of equations,which are difficult to *** obtain a problem that is computationally tractable,we first analyze the relative importance of the Stokes and Darcy terms for a set of idealized 2D *** find that,in terms of effective permeability,the Stokes-Brinkman equations are only applicable for a special parameter set where the effective free-flow permeability is less than four orders of magnitude different from the matrix *** other cases can be accurately modeled with either the Stokes or the Darcy end-member flows,depending on if there do or do not exist percolating free-flow *** insights obtained are used to perform a direct computation of the effective permeability of a rock sample model with more than 8 million cells.

关键词： Upscaling Stokes equation Brinkman equation porous media

Sm-Nd Isotopic Study on Metavolcano-sedimentary Rocks of Wenduermiao Group, Inner Mongolia, People's Republic of China

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Chinese Science Bulletin 1994年第16期39卷 1367-1371页

作者：聂凤军裴荣富吴良士 Arne Bjr■lykke Institute of Mineral Deposits Chinese Academy of Geological Science Beijing 100037 PRC department of geology University of Oslo P. O. Box 1047 Blindern Oslo Norway

The Wenduermiao Group consisting of mainly submarine volcano-sedimentary rocks with low to middle metamorphic grade outcrops around Zhurihe town located between Erlianhot and Jining cities. The Wenduermiao Group is characterized by having iron deposits or prospects, discontinuous ophiolite lenses and mineral assemblages formed under high pressure. All these geologic features have been regarded as evidences of existence of the Early Paleozoic submarine trench. The study

关键词： Sm-Nd isotope Neoproterozoic era Wendnermiao Inner Mongolia.

Modelling Hydrological Consequences of Climate Change—Progress and Challenges

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Advances in Atmospheric Sciences 2005年第6期22卷 789-797页

作者： Chong-yu XU Elin WIDEN Sven HALLDIN department of Geosciences University of Oslo P. O. Box 1047 Blindern N-0316 Oslo Norway department of Earth Sciences Uppsala University Villavagen 16 S-75236 Uppsala Sweden Nanjing Institute of Geography and Limnology Chinese Academy of Sciences

The simulation of hydrological consequences of climate change has received increasing attention from the hydrology and land-surface modelling communities. There have been many studies of climate-change effects on hydrology and water resources which usually consist of three steps：（1） use of general circulation models （GCMs） to provide future global climate scenarios under the effect of increasing greenhouse gases, （2） use of downscaling techniques （both nested regional climate models, RCMs, and statistical methods） for ＂downscaling＂ the GCM output to the scales compatible with hydrological models, and （3） use of hydrologic models to simulate the effects of climate change on hydrological regimes at various scales. Great progress has been achieved in all three steps during the past few years, however, large uncertainties still exist in every stage of such study. This paper first reviews the present achievements in this field and then discusses the challenges for future studies of the hydrological impacts of climate change.

关键词： climate change water-resources assessment water balance regional scale hydrological models review

Well-Posedness of Stochastic Continuity Equations on Riemannian Manifolds

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Chinese Annals of Mathematics,Series B 2024年第1期45卷 81-122页

作者： Luca GALIMBERTI Kenneth H.KARLSEN department of Mathematical Sciences NTNU Norwegian University of Science and TechnologyN-7491 TrondheimNorway department of mathematics University of OsloP.O.Box 1053BlindernN-0316 OsloNorway

The authors analyze continuity equations with Stratonovich stochasticity,■ρ+divh[ρo(u(t,x)+∑_(i=1)^(N)a_(i)(x)w_(i)(t))]=0defined on a smooth closed Riemannian manifold M with metric *** velocity field u is perturbed by Gaussian noise terms Wi(t),:WN(t)driven by smooth spatially dependent vector fields a1(x),...,aN(x)on *** velocity u belongs to L_(t)^(1)W_(x)^(1,2)with divh u bounded in Lf,for p>d+2,where d is the dimension of M(they do not assume div_(h) u∈L_(t,x)^(∞)).For carefully chosen noise vector fields ai(and the number N of them),they show that the initial-value problem is well-posed in the class of weak L^(2) solutions,although the problem can be ill-posed in the deterministic case because of concentration *** proof of this“regularization by noise”result is based on a L^(2) estimate,which is obtained by a duality method,and a weak compactness argument.

关键词： Stochastic continuity equation Riemannian manifold Hyperbolic equa-tion Non-smooth velocity field Weak solution Existence Uniqueness

Representation of Infinite-Dimensional Forward Price Models in Commodity Markets

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Communications in Mathematics and Statistics 2014年第1期2卷 47-106页

作者： Fred Espen Benth Paul Krühner Centre of Mathematics for Applications University of OsloP.O.Box 1053Blindern0316 OsloNorway department of Mathematics University of OsloP.O.Box 1053Blindern0316 OsloNorway

We study the forward price dynamics in commodity markets realised as a process with values in a Hilbert space of absolutely continuous functions defined by Filipovi´c(Consistency problems for Heath–Jarrow–Morton interest rate models,2001).The forward dynamics are defined as the mild solution of a certain stochastic partial differential equation driven by an infinite-dimensional Lévy *** is shown that the associated spot price dynamics can be expressed as a sum of Ornstein–Uhlenbeck processes,or more generally,as a sum of certain stationary *** results link the possibly infinite-dimensional forward dynamics to classical commodity spot *** continue with a detailed analysis of multiplication and integral operators on the Hilbert spaces and show that Hilbert–Schmidt operators are essentially integral *** covariance operator of the Lévy process driving the forward dynamics and the diffusion term can both be specified in terms of such operators,and we analyse in several examples the consequences on model dynamics and their probabilistic ***,we represent the forward price for contracts delivering over a period in terms of an integral operator,a case being relevant for power and gas *** several examples,we reduce our general model to existing commodity spot and forward dynamics.

关键词： Forward price Infinite-dimensional stochastic processes Lévy processes Commodity markets Heath–Jarrow–Morton approach

The Bamble Sector,South norway:A review

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Geoscience Frontiers 2014年第5期5卷 635-658页

作者： Timo G.Nijland Daniel E.Harlov Tom Andersen TNO P.O.Box 49.2600 AA Delft.The Netherlands GeoForschungsZentrum Telegrafenberg14473 Potsdam.Germany department of geology.university of Johannesburg P.O.Box 524.Auckland Park 2006.South Africa department of Geosciences.university of oslo P.O.box 1047.Blindern.0316 oslo Norway

The Proterozoic Bamble Sector, South norway, is one of the world＇s classic amphiboliteto granulite- facies transition zones. It is characterized by a well-developed isograd sequence, with isolated ＇granulite-facies islands＇ in the amphibolite-facies portion of the transition zone. The area is notable for the discovery of C02-dominated fluid inclusions in the granolite-facies rocks by Jacques Touter in the late 1960＇s, which triggered discussion of the role of carbonic fluids during granulite genesis. The aim of this review is to provide an overview of the current state of knowledge of the Bamble Sector, with an emphasis on the Arendal-Froland-Nelaug-Tvedestrand area and off shore islands （most prominantly Tromay and Hisoy） where the transition zone is best developed. After a brief overview of the history of geological research and mining in the area, aspects of sedimentary, metamorphic and magmatic petrology of the Bamble Sector are discussed, including the role of fluids. Issues relevant to current geotectonic models for SW Scandinavia, directly related to the Bamble Sector, are discussed at the end of the review.

关键词： Bamble SectorSouth norwayCharnockiteAmphibolire- ro granulire-facies transitionCO2BrinesPrecambrian

The Role of Inertia and Dissipation in the Dynamics of the Director for a Nematic Liquid Crystal Coupled with an Electric Field

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Communications in Computational Physics 2015年第6期18卷 147-166页

作者： Peder Aursand Johanna Ridder department of Mathematical Sciences Norwegian University of Science and TechnologyNO–7491 TrondheimNorway department of Mathematics University of OsloP.O.Box NO-1053BlindernOslo-0316Norway

We consider the dynamics of the director in a nematic liquid crystal when under the influence of an applied electric *** an energy variational approach we derive a dynamic model for the director including both dissipative and inertial forces.A numerical scheme for the model is proposed by extending a scheme for a related variational wave *** experiments are performed studying the realignment of the director field when applying a voltage difference over the liquid crystal *** particular,we study how the relative strength of dissipative versus inertial forces influence the time scales of the transition between the initial configuration and the electrostatic equilibrium state.

关键词： Nematic liquid crystals Freedericksz transition dynamics of director fields