Geochemical characterization of felsic metavolcanic rocks hosting the Archean Taivaljärvi Ag-Zn-Pb-Au deposit in the Tipasjärvi greenstone belt, eastern Finland

Abstract. The Taivaljärvi Ag-Zn-Pb-Au deposit is located in the Archean Tipasjärvi greenstone belt (TGB) in eastern Finland, which is part of the Tipasjärvi-Kuhmo-Suomussalmi greenstone complex. The deposit is hosted by strongly altered felsic meta-volcanic rocks and has silver as its main commodity. Geochemical characterization of the host unit of the Taivaljärvi deposit, the Koivumäki Formation, was carried out along the entire TGB. Samples of metavolcanics rocks from different profiles across the TGB were analyzed for whole-rock major and trace element chemistry, including hanging-wall, ore zone and footwall samples from the silver mine. Detailed lithogeochemical exploration techniques were applied in order to identify potential areas for new discoveries in the belt. Once fertile areas were delineated, they were contrasted with other areas of so far unproven fertility using lithogeochemical data coupled with normative mineral plots, mass-balance calculations, alteration indexes and petrographic observations. Areas of lesser and greater potential for mineralization styles similar as those of the Taivaljärvi deposit were subsequently identified. There are two main groups of felsic metavolcanic rocks. Those from the mine and the Kivisuo-Talassuo, Lapasuo and South Jäkäläsuo profiles are mainly rhyolites whereas those from the Palovaara, Katajasuo profiles and most of Koraminvaara profiles range from rhyodacites to dacites. All the rocks show a calcalkaline to transitional trend and a trace element signature of a continental arc geological setting. The main alteration processes are sericitization, chloritization and silicification. Felsic metavolcanic rocks from the mine area are of FII affinities, and show gently sloping REE patterns with La/YbN ratios of 5.5–8, moderately high Zr/Y ratios, intermediate HFSE concentrations, and negative Eu anomalies (Eu/Eu* 0.35–0.55). They indicate mass gains in K₂O, SiO₂, MgO and several metals (Ag, Pb, Zn, Au), moderate mass gains in FeO as well as depletion in Na₂O and CaO. The areas that show similar trace element signatures and mass-transfer patterns together with petrographic and geochemical evidence for alteration are Lapasuo and Kivisuo-Talassuo, followed less clearly by Koraminvaara. On the other hand, the Koivumäki, South Jäkäläsuo and Palovaara areas have different characteristics, being less favorable as exploration targets

Energy rating of a water pumping station using multivariate analysis

Among water management policies, the preservation and the saving of energy demand in water supply and treatment systems play key roles. When focusing on energy, the customary metric to determine the performance of water supply systems is linked to the definition of component-based energy indicators. This approach is unfit to account for interactions occurring among system elements or between the system and its environment. On the other hand, the development of information technology has led to the availability of increasing large amount of data, typically gathered from distributed sensor networks in so-called smart grids. In this context, data intensive methodologies address the possibility of using complex network modeling approaches, and advocate the issues related to the interpretation and analysis of large amount of data produced by smart sensor networks. In this perspective, the present work aims to use data intensive techniques in the energy analysis of a water management network. The purpose is to provide new metrics for the energy rating of the system and to be able to provide insights into the dynamics of its operations. The study applies neural network as a tool to predict energy demand, when using flowrate and vibration data as predictor variables

Existence and homogenization of the Rayleigh-B\'enard problem

The Navier-Stokes equation driven by heat conduction is studied. As a prototype we consider Rayleigh-B\'enard convection, in the Boussinesq approximation. Under a large aspect ratio assumption, which is the case in Rayleigh-B\'enard experiments with Prandtl number close to one, we prove the existence of a global strong solution to the 3D Navier-Stokes equation coupled with a heat equation, and the existence of a maximal B-attractor. A rigorous two-scale limit is obtained by homogenization theory. The mean velocity field is obtained by averaging the two-scale limit over the unit torus in the local variable

Advanced Design of Semantic Web Portal: ODESeW2

This poster presents a rapid web application development framework to build semantic por-tals. This framework is composed of reusable views of semantic information, ontology views and an intelligent controller, as elements of the Model-View-Controller design paradigm

Algebraic Renormalization of Parity-Preserving QED_3 Coupled to Scalar Matter II: Broken Case

In this letter the algebraic renormalization method, which is independent of any kind of regularization scheme, is presented for the parity-preserving QED_3 coupled to scalar matter in the broken regime, where the scalar assumes a finite vacuum expectation value, $= v$. The model shows to be stable under radiative corrections and anomaly free.Comment: 9 pages, latex, no figure

An algebraic proof on the finiteness of Yang-Mills-Chern-Simons theory in D=3

A rigorous algebraic proof of the full finiteness in all orders of perturbation theory is given for the Yang-Mills-Chern-Simons theory in a general three-dimensional Riemannian manifold. We show the validity of a trace identity, playing the role of a local form of the Callan-Symanzik equation, in all loop orders, which yields the vanishing of the beta-functions associated to the topological mass and gauge coupling constant as well as the anomalous dimensions of the fields.Comment: 5 pages, revte