Influence of wind upon water quality in Liverpool Bay

Comprehensive distribution patterns of physical and chemical characteristics have been obtained from a series of cruises in Liverpool Bay. The marked feature of these distributions was their temporal variability, suggesting that the surface residual circulation is also temporally variable. The influence of wind stress upon the circulation pattern and hence water quality of this sea area is illustrated.     

Rock salt mass in the Paleoproterozoic sequence of the Onega trough in Karelia (from the Onega parametric well data)

A thick (200 m) rock salt mass covering Late Archean granitoids was exposed for the first time in the Early Proterozoic volcanogenic-sedimentary formations in the Onega trough of the east Baltic Shield by the Onega parametric well. The mineral composition of salts, their geochemical features, and the isotopic composition of carbonate carbon and oxygen have been studied. After fluid inclusions present in salts, their metamorphism temperature and isotopic composition of helium and argon were determined. The obtained results give evidence of the fact that rock salts and magnesites associated with them were formed in an evaporate basin with participation of deep crustal processes. The age of the underlying granitoids (2.716 ± 9 Ma) is determined using the Pb—Pb method.     

Developing a modern pollen–climate calibration data set for Norway

Bjune, A. E., Birks, H. J. B., Peglar, S. M. & Odland, A. 2010: Developing a modern pollen–climate calibration data set for Norway. Boreas, Vol. 39, pp. 674–688. 10.1111/j.1502‐3885.2010.00158.x. ISSN 0300‐9483. Modern pollen–climate data sets consisting of modern pollen assemblages and modern climate data (mean July temperature and mean annual precipitation) have been developed for Norway based on 191 lakes and 321 lakes. The original 191‐lake data set was designed to optimize the distribution of the lakes sampled along the mean July temperature gradient, thereby fulfilling one of the most critical assumptions of weighted‐averaging regression and calibration and its relative, weighted‐averaging partial least‐squares regression. A further 130 surface samples of comparable taphonomy, taxonomic detail and analyst became available as a result of other projects. These 130 samples, all from new lakes, were added to the 191‐lake data set to create the 321‐lake data set. The collection and construction of these data sets are outlined. Numerical analyses involving generalized linear modelling, constrained ordination techniques, weighted‐averaging partial least‐squares regression, and two different cross‐validation procedures are used to asses the effects of increasing the size of the calibration data set from 191 to 321 lakes. The two data sets are used to reconstruct mean July temperature and mean annual precipitation for a Holocene site in northwest Norway and a Lateglacial site in west‐central Norway. Overall, little is to be gained by increasing the modern data set beyond about 200 lakes in terms of modern model performance statistics, but the down‐core reconstructions show less between‐sample variability and are thus potentially more plausible and realistic when based on the 321‐lake data set.     

Beitrag zur quantitativen Analyse von Mineralphasen mittels Röntgendiffraktion

Zusammenfassung Bei der Durchführung quantitativer Gemenge-Analysen mit Hilfe der Röntgendiffraktionsmethode kann man den Massenschwächungskoeffizienten (^*) verwenden, den man bei der Röntgenfluoreszenzanalyse Röhrenhauptlinienverfahren vonSchroll-Stepon erhalten hat. Er wird von der Wellenlänge der Röntgenfluoreszenzstreustrahlung auf die Wellenlänge der Diffraktionsröhre transformiert. Ein Intensitäts-Konzentrationsdiagramm, in dem die Intensität der gewählten Diffraktionslinie durch das Produkt von Intensität und dem jeweiligen Wert von ^* ersetzt wird, ergibt eine allgemeingültige Eichgerade. Als Beispiel werden Messungen an Zweistoffsystemen wie Magnesit-Quarz, Albit-Quarz, Calcit-Quarz, Stilpnomelan-Quarz und Siderit-Quarz angeführt.Die vorgeschlagene Methode ist für kombinierte Diffraktions- und Röntgenfluoreszenzanalysen sehr zweckmäßig.

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Summary Applicating the quantitative X-ray-diffraction-analysis für mixtures of minerals the use of the mass absorption coefficient (^*) is possible, which is received by the X-ray-fluorescence-analysis of the same sample following the method proposed by the authors. The mass absorption coefficients must be transformed to the new wave length of the X-ray-diffraction tube. In the intensity-concentration-diagram the intensity is substituted by the product of intensity and mass absorption coefficient. An uniform standard line is received, as the measurement of quartz shows in the systems of two-substances, such as magnesite-quartz, albite-quartz, calcite-quartz, stilpnomelan-quartz and siderite-quartz.The proposed method is very useful for the combined X-ray-diffraction and X-ray fluorescence analysis.

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The Karoo Basin of South Africa: type basin for the coal-bearing deposits of southern Africa

The coal-bearing sediments and coal seams of the Karoo Basin, Southern Africa are described and discussed. The Karoo Basin is bounded on its southern margin by the Cape Fold Belt, onlaps onto the Kaapvaal Craton in the north and is classified as a foreland basin. Coal seams are present within the Early Permian Vryheid Formation and the Triassic Molteno Formation.The peats of the Vryheid Formation accumulated within swamps in a cool temperate climatic regime. Lower and upper delta plain, back-barrier and fluvial environments were associated with peat formation. Thick, laterally extensive coal seams have preferentially accumulated in fluvial environments. The coals are in general inertinite-rich and high in ash. However, increasing vitrinite and decreasing ash contents within seams occur from west to east across the coalfields. The Triassic Molteno coal seams accumulated with aerially restricted swamps in fluvial environments. These Molteno coals are thin, laterally impersistent, vitrinite-rich and shaly, and formed under a warm temperate climatic regime.Palaeoclimate, depositional systems, differential subsidence and basin tectonics influence to varying degrees, the maceral content, thickness and lateral extent of coal seams. However, the geographic position of peat-forming swamps within a foreland basin, coupled with basin tectonics and differential subsidence are envisaged as the primary controls on coal parameters. The Permian coals are situated in proximal positions on the passive margin of the foreland basin. Here, subsidence was limited which enhanced oxidation of organic matter and hence the formation of inertinitic coals. The coals in this tectonic setting are thick and laterally extensive. The Triassci coals are situated within the tectonically active foreland basin margin. Rapid subsidence and sedimentation rates occurred during peat formation which resulted in the preservation of thin, laterally impersistent, high ash, vitrinite-rich, shaly coals.     

Principles of tabling

The mechanism of concentration on the shaking table is discussed and a fresh attempt is made to obtain the theoretical model describing the velocity of a fluid in depth and time when in contact with a symmetrically reciprocating surface.The significance of the many design and operational variables and their interrelationships are examined. The various areas where the shaking table plays its role are then considered.The relevant features of micropanner, superpanner and the subsequent macropanner and pulsepanner are also treated since they all, like the shaking table, have the differential motion in common.     

Rock warming and drying under simulated intertidal conditions,part II: weathering and biological influences on evaporative cooling and near‐surface micro‐climatic conditions as an example of biogeomorphic ecosystem engineering

The way in which rocks and engineering materials heat‐up and dry‐out in the intertidal zone is of relevance to both weathering and ecology. These behaviours can be measured in the laboratory under controlled conditions designed to replicate those occurring in the field. Previous studies have demonstrated differences in thermal behaviours between rock types and through time as a result of soiling in terrestrial environments, but the influence of weathering and colonization on rock behaviours in the intertidal zone has not been previously assessed. We measured the warming and drying of blocks of rock (limestone and granite) and marine concrete during ‘low‐tide’ events simulated in the laboratory, before and after a period of exposure (eight months) on rock platforms in Cornwall, UK. As well as differences between the material types, temperatures of control (unexposed) and field‐exposed blocks differed in the order of 1 to 2 °C. Drying behaviours were also different after field exposure. Differences during the first few hours of exposure to air and heat were attributed to discolouration and albedo effects. Over longer periods of time, changes in the availability of near‐surface pore water as a result of micro‐scale bioerosion of limestone and the development of bio‐chemical crusts on marine concrete [observed using scanning electron microscopy (SEM)] are suggested as mechanisms enhancing and reducing, respectively, the efficiency of evaporative cooling. The retention of moisture by epilithic biofilms may also influence thermal and drying behaviours of granite. These observations represent one of the first examples of cross‐scalar biogeomorphic linkages in the intertidal zone. The significance of the results for the subsequent efficiency of weathering, and near‐surface micro‐climatic conditions experienced by colonizing organisms is discussed. The involvement of microorganisms in the creation of more (or less) ecologically stressful conditions through the alteration of substratum geomorphic properties and behaviours is suggested as an example of ‘biogeomorphic ecosystem engineering’. Copyright © 2011 John Wiley & Sons, Ltd.