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. Volcanol. Geotherm. Res., 2003, 123, 43–61 http://dx.doi.org/10.1016/S0377-0273(03)00027-1 [24] [24] Carrasco-Núñez G., Riggs, N.R., Polygenetic nature of a rhyolitic dome and implications for hazard assessment: Cerro Pizarro volcano, Mexico, J. Volcanol. Geotherm. Res., 2008, 171, 307–315 http://dx.doi.org/10.1016/j.jvolgeores.2007.12.002 [25] [25] Kereszturi G., Németh K., Controlling conditions of phreatomagmatic to magmatic fragmentation styles of Pliocene volcanoes of West-Hungary, In: Haller M.J., Massaferro G.I. (Eds.), 3rd International Maar Conference (14

Abstract

Der Beitrag zeichnet die historische Motivation der Bezeichnungen für ‘Flohmarkt’ in den westeuropäischen Sprachen nach (Flohmarkt/Läusemarkt, marché aux puces, mercato delle pulci, flea market, etc.) und erörtert das Verhältnis zu den älteren osteuropäischen und orientalischen Entsprechungen (russ. вшивый рынок, türk. bit bazar).

changing nature of ME multilingualism; then some specific research questions are introduced, such as the controversial issue of ME creolization, the frequent use of code-switching in medieval texts, and the possible Celtic influence on English. The remaining sections deal in some detail with contact-induced change on the various linguistic levels: while foreign lexical influence is well established, contact-induced structural changes are more controversial, since here a native origin is often equally possible. In many cases, especially of syntactic change, a polygenetic

.D.: Keanakakoi Ash Member. Bull. Volcanol., 1990, 52, 334–354 http://dx.doi.org/10.1007/BF00302047 [30] Giordano G., Facies characteristics and magma-water interaction of the White Trachytic Tuffs (Roccamonfina Volcano, southern Italy). Bull. Volcanol., 1998, 60, 10–26 http://dx.doi.org/10.1007/s004450050213 [31] Németh K., Monogenetic volcanic fields: Origin, sedimentary record, and relationship with polygenetic volcanism. Geol. Soc. Am., 2010, 470, 43–66 [32] Sato H., Aramaki S., Kusakabe M., Hirabayashi J.-I., Sano Y., Nojiri Y., Tchoua F., Geochemical difference of

in back-scattered electron (BSE) images or young domains less than 5 μm in width located inside an older core. In both cases, using age maps as a template for locating in-situ analysis points will minimize the peril of age mixing and erroneous geological interpretations. In addition to providing critical information for illustrating and interpreting the history of complex polygenetic monazite, age mapping may ultimately lead to a better understanding of the processes involved with monazite growth and recrystallization, and thus, even more powerful applications

.B., Conway F.M., Basaltic volcanic fields. In: Sigurdsson H., Houghton B.F., McNutt S.R., Rymer H., Stix J. (Eds.), Encyclopedia of Volcanoes, Academic Press, San Diego, 2000, 331–343 [38] Valentine G.A., Gregg T.K.P., Continental basaltic volcanoes — Processes and problems. J. Volcanol. Geoth. Res., 2008, 177, 857–873 [39] Németh K., Monogenetic volcanic fields;their origin, sedimentary record, relationship with polygenetic volcanism, and how monogenetic they are. In: Canon-Tapia E., Szakacs A., (Eds. ) What is a volcano? Geological Society of America, 2010 (in press

Abstract

A small piece of the Morasko meteorite, weighing 970 g, yields traces of its journey through the Earth’s atmosphere and of its impact into a mineral substrate, such as reflected in the meteorite’s crust. This is seen in the crust structure in the form of sintered as well as fusion and semi-fusion layers for which ablative niches are optimum sites. Subsequent weathering processes have resulted in significant mineralogical changes in the crusts. The meteorite crusts originated during polygenetic processes.

eastern Wyoming Craton (U.S.A.) PETER S. DAHL,1,* MICHAEL A. HAMILTON,2,† MICHAEL J. JERCINOVIC,3 MICHAEL P. TERRY,3,‡ MICHAEL L. WILLIAMS,3 AND ROBERT FREI4 1Department of Geology, Kent State University, Kent, Ohio 44242, U.S.A. 2J.C. Roddick Ion Microprobe (SHRIMP II) Laboratory, Geological Survey of Canada, 601 Booth Street, Ottawa, Ontario K1A 0E8, Canada 3Department of Geosciences, University of Massachusetts, Amherst, Massachusetts 01003, U.S.A. 4Geological Institute, University of Copenhagen, Øster Voldgade 10, DK-1350 Copenhagen, Denmark ABSTRACT Polygenetic

Abstract

Upper Precambrian diamictites in Varangerfjorden (northern Norway) have been examined for evidence of origin, whether glaciogenic, gravity flow or polygenetic. Studies of geomorphology, sedimentology and surface microtextures on quartz sand grains are integrated to provide multiple pieces of evidence for the geological agents responsible for the origin of the diamictites. The documented sedimentary and erosional structures, formerly interpreted in a glaciogenic context (e.g., diamict structure, pavements and striations) have been reanalysed. Field and laboratory data demonstrate that, contrary to conclusions reached in many earlier studies, the diamictites and adjacent deposits did not originate from glaciogenic processes. Evidence from macrostructures may occasionally be equivocal or can be interpreted as representing reworked, glacially derived material. Evidence from surface microtextures, from outcrops which are believed to exhibit the most unequivocal signs for glaciation, display no imprint at all of glaciogenic processes, and a multicyclical origin of the deposits can be demonstrated. The geological context implies (and no geological data contradict this) an origin by gravity flows, possibly in a submarine fan environment. This reinterpretation of the diamictites in northern Norway may imply that the palaeoclimatological hypothesis of a deep frozen earth during parts of the Neoproterozoic has to be revised.