Geomagnetic activity as a possible cause of changes in the middle atmosphere and troposphere; observations made in Prague in the years 1932–1987

Summary A possible relation between the 10-day, 1-month, and 2-month geomagnetic as well as solar activity, characterized by Kp and Wolf's number R, and temperatures measured at the Prague-Klementinum meteorological station in January–February of the years 1932–1987 was sought. It was found that:1) Kp correlates with the temperature in Prague better than Wolf's number R.2) If the QBO phase is taken into account, the correlations improve.3) Even if the correlations improves with increasing length of the subintervals into which the individual winter periods (January-February) were derived, their statistical significance declines.     

Some results of biogeographic research on meadows in the Dyje-Svratka basin in the Czech Republic

Some results of biogeographic research on meadows in the Dyje-Svratka basin in the Czech Republic. The paper shows one example of biogeographic inventory of natural ecosystems in an unflooded meadow in the Dyje-Svratka basin. It is part of the complex physio-geographic research of the Geographic Department of the Masaryk University in Brno aimed at gaining a basis for territorial interpretation of ecological regularities and territorial application of general ecological optimizing principles. A segment of biocenosis of Ulmi-fraxineta carpini has been analyzed (Zlatník 1956).The endeavour of Czech geographers to study geosystems of various dimensions completely gets in the limelight. In question is the understanding of mutual relationship of components of geosystems based on the exchange of mass and energy. There are two ways of studying them: spatial relations or approaches concentrated on processes. In contrast to the above unilateral concept, the endeavour to make the approaches compatible appears rarely. This complex view is made possible by geobiocenologically taken biogeography in papers of Zlatník and Rauer, their students and successors. This paper shows only one example of the results of biogeographic stock-taking of meadows in the Dyje-Svratka basin, indicating relations of eco- and geosystems which confirm the necessity of ecological orientation of the present biogeography and its potential contribution to ecology.     

Magnetic properties,self-reversal remanence and thermal alteration products of smythite

Summary This study is a follow up of the investigation of some magnetic properties and metastability of greigite in samples obtained from Miocene claystones in the Kruné hory (Erzgebirge) Piedmont basins (Bohemia). Three different methods of upgrading the smythite were applied; the magnetic properties of the concentrates are compared. The thermal conversion of smythite sets in at 200°C while greigite converts at 250°C. The first intermediate products to be formed are iron sulphides, marcasite clearly dominating over pyrite and pyrrhotite. Apart from a Fe³⁺ sulphate with a composition of Fe₂(SO₄)₃, oxidation of these sulphides gives rise to -Fe₂O₃. The result of the subsequent decomposition of the mentioned sulphate is the formation of -Fe₂O₃, which retains the sulphate structure. The final product of the thermal decomposition at 800°C is -Fe₂O₃. In the smythite concentrate the conversion to Fe³⁺ sulphate and -Fe₂O₃ is about twice as intensive as in greigite. No direct conversion to -Fe₂O₃ was found. During the thermal process self-reversals of remanence were observed, in various samples as many as four reversals in the temperature interval from 340 to 590°C. The occurrences of self-reversals of remanence were only observed at high degrees of thermal demagnetization, of the order of 10^–2 down to 10^–3 in the temperature interval of sulphide origin (below 400°C), and of the order of 10^–4 down to 10^–6 in the temperature interval of Fe-oxides origin (above 400°C).Presented at the 3rd Conference on New Trends in Geomagnetism, Castle of Smolenice, Czechoslovakia, June 22–29, 1992     

Die Rheingrabenrandverwerfung im Wattkopftunnel bei Ettlingen (Nordschwarzwald)

The Wattkopftunnel, near Ettlingen (Nordschwarzwald), drives through the eastern margin of the Rheingraben. The tunnel passes cenozoic and mesozoic sediments. Early quarternary and tertiary beds are situated west of the main thrust of the Rheingraben. Fossil record indicates upper Oligocene age (Chatt) for parts of the tertiary sediments. At the eastern border of the Rheingraben, wedges of jurassic and middle triassic series are squeezed. East of the Rheingraben the tunnel drives in the lower triassic Bausandstein. The eastern margin of the Rheingraben was investigated in detail during tunneling. Faults of the Rheingraben margin are distributed in an 130 meter wide fault zone in the tunnel. Total stratigraphic separation by the normal faults reaches more than 2 000 meters. The cenozoic sequence suffered synsedimentary to early diagenetic deformation, while the mesozoic series are characterized by ruptural deformation. The fault- and joint system is directed in the rheinische Richtung (SSW-NNE). East of the Rheingraben a second direction occur, running parallel to the lower Albtal (W-E).

     

The history and impact of air pollution at Čertovo Lake,southwestern Czech Republic

This multi-disciplinary investigation documents the longterm effects of atmospheric pollution of metals and acids on a geologically sensitive catchment in the umava Mountains, southwestern Czech Republic, a region with a long history of human disturbance. A 30 cm long sediment core (I) from ertovo Lake was analyzed for natural and artifical radionuclides, metals, diatoms, chrysophytes, and pollen in sediments accumulated during the last 200 years. A second core (II), extending to 95 cm, included sediment judged to be free of atmospheric deposition of pollutants associated with the Industrial Revolution. Chronostratigraphic markers include several changes in the pollen assemblages corresponding to well-documented changes in land-use, and distinct distributions of ¹³⁷Cs, ¹³⁴Cs and ²⁴¹Am from weapons testing and the 1986 nuclear accident at Chernobyl, Russia. These markers corroborate the ²¹⁰Pb dating and, together, produce a reliable chronology extending back nearly to 1800 A.D.Stratigraphic profiles of Cu, Pb, and Zn in Core I are unlike any previously reported in the literature. Concentrations of Cu, Pb, and Zn remain generally above 100, 400, and 200 g g^-1, respectively, for the 200 years represented by Core I. These values are unusually high for sediments from a watershed with no known heavy-metal ore bodies. Accumulation rates for Cu, Pb, and Zn, which include both atmospheric and watershed contributions, are also high (ca 1, > 1 and > 1 g cm^-2 yr^-1, respectively) for the same period, although the anthropogenic contribution of Zn rose from nearly zero at 1800 A.D. The Cu and Pb accumulation rates rose dramatically about 1640 A.D.Accumulation rates of anthropogenically-derived Be, a relatively abundant element in the soft coals of the region, are also elevated by about 0.01 g cm^-2 yr^-1 in sediments of this period. Vanadium accumulation rates increased only since 1980 A.D., presumably along with increased consumption of oil.Diatom assemblages illustrate that the lake was acidic (pH between 4.5 and 5) through at least the past 200 years. The pH declined significantly (from ca 5 to 4) between 1960 and 1985 with a slight increase to 4.5 in the last few years. Recent diatom and chrysophyte assemblages suggest high trace metal concentrations, consistent with the present lake-water chemistry.     

A calibration system for superconducting gravimeters

A new method for the calibration of a superconducting gravity meter is described, in which a 273 Kg annular mass is placed around the meter and is moved up and down. The geometry of the apparatus is easy to model and the accuracy in the computation of the gravity variation induced by the mass, 6.7µgal, is limited only by the accuracy in the knowledge of value of the gravitational constant. Measurements done in 91 and 92 for the calibration of the instrument GWR-T015 are described. The calibration factor has been determined with a precision of about 0.3%.     

The use of rogation ceremony records in climatic reconstruction: a case study from Catalonia (Spain)

The use of rogation ceremonies due to environmental causes constitutes an important source of information in paleoclimatic reconstructions. Their specific characteristics and full documental records permit highly reliable series to be reconstructed with daily, monthly, seasonal or annual resolution over periods of several centuries (3–4 centuries in the case of Catalonia). The levels of intensity, reflected in the type of religious ceremony enacted, allows quantification. Comparative analysis is made possible by the similarity of the mechanisms developed in different localities. The use of these series in paleoclimatological studies is a promising line of research, particularly as regards the pro pluvia rogations celebrated in the Mediterranean countries and in South America.     

River related tourism in Europe — an overview

This paper gives an overview of different types of river-oriented tourism in Europa. All of them belong to the growing sectors of the business. They are based on essential characteristics of river landscapes as common factors of attractiveness. A series of supply-oriented indicators is used to draw up a ranking of the European river-cruise-districts. The cruising market is characterized by extensive investment strategies of some leading companies. In order to attract also younger people and families, they have to develop new structures of supply. The canal-systems of Western Europe form the most important prerequisite for houseboat-tourism. It's main districts can be ranked by the indicator: number of the types of charterable boats. The rising request for adventures and progress in kayak- and raft-technology are driving factors to whitewater-tourism. It's more important districts in the Alps, Pyrenees as well as in different medium mountains are shown. The shift into higher mountain regions causes ecological problems and severe personal risks. Biking has become a prefered leisure activity with river basins as the main goal areas. Some essential characteristics are given by the examples of two most significant routes: the Austrian Danubetrail and the Bavarian Altmühl-route. Finally, the planning concept of integral management of river basins is discussed which should support and coordinate the different styles of river-oriented tourism.     

Geochronology and geochemistry of eclogites from the Mariánské Lázně Complex,Czech Republic: Implications for Variscan orogenesis

The Mariánské Lázn complex (MLC) is located in the Bohemian Massif along the north-western margin of the Teplá-Barrandian microplate and consists of metagabbro, amphibolite and eclogite, with subordinate amounts of serpentinite, felsic gneiss and calcsilicate rocks. The MLC is interpreted as a metaophiolite complex that marks the suture zone between the Saxothuringian rocks to the north-west and the Teplá-Barrandian microplate to the south-east. Sm-Nd geochronology of garnet-omphacite pairs from two eclogite samples yields ages of 377±7, and 367±4 Ma. Samples of eclogite and amphibolite do not define a whole rock Sm-Nd isochron, even though there is a large range in Sm/Nd ratio, implying that the suite of samples may not be cogenetic. Eclogites do not have correlated _Nd values and initial ⁸⁷Sr/⁸⁶Sr ratios. Five of the eight eclogite samples have high _Nd values (+10.2 to +7.1) consistent with derivation from a MORB-like source, but variable ⁸⁷Sr/⁸⁶Sr ratios (0.7033 to 0.7059) which probably reflect hydrothermal seawater alteration. Three other eclogite samples have lower _Nd values (+ 5.4 to –0.8) and widely variable ⁸⁷Sr/⁸⁶Sr ratios (0.7033 to 0.7096). Such low _Nd values are inconsistent with derivation from a MORB, source and may reflect a subduction or oceanic island basalt component in their source. The MLC is an important petrotectonic element in the Bohemian Massif, providing evidence for Cambro-Ordovician formation of oceanic crust and interaction with seawater, Late Devonian (Frasnian-Famennian) high- and medium-pressure metamorphism related to closure of a Saxothuringian ocean basin, Early Carboniferous (Viséan) thrusting of the Teplá terrane over Saxothuringian rocks and Late Viséan extension.     

Problems connected with the tangential metric coefficient in the Schwarzschild metric: A possible solution

Four situations are shown where the Schwarzschild metric cannot be used or is subject to unsurmountable problems. The first is the question of a metric useful for PPN-formalism checking different gravitational theories. The second problem occurs in connection with Mach's principle, when the flatness of the spacetime inside a massive hollow sphere is a generally accepted solution. The metrical discontinuity on the same spherical shell is a third problem. The fourth one is the anisotropy of the mass-energy of a test particle in the gravitational field. Three principles for solution are proposed:

1. The space is not dilated, but rather contracted, in the gravitational field; then the measurement-rods are shorter and measured distances have greater magnitudes.
2. The potential energy is to be related to a potential level where a stationary observer is placed and the general relativistic potential must be used.
3. A new metric must be introduced which is distinct from the Schwarzschild metric, so that the space in the gravitational field is warped isotropically.

Then the problems stated are shown to be easily solvable.