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First Polish textbooks on mineralogy

First Polish textbooks on mineralogy

First Polish textbooks on mineralogy, published between 1780s-1820s mostly in Vilna, are presented and their contents briefly discussed. Authors of these textbooks, lecturing at the Vilna University, being A. G. Werner's students, played an important role in propagating most recent ideas in mineralogy and related sciences. They were also the authors of pioneer Polish mineralogical nomenclature, which corresponded to the internationally recognised terms.

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The Oligocene Reifnitz tonalite (Austria) and its host rocks: implications for Cretaceous and Oligocene–Neogene tectonics of the south-eastern Eastern Alps

Abstract

In the south-eastern Eastern Alps, the Reifnitz tonalite intruded into the Austroalpine metamorphic basement of the Wörthersee half-window exposed north of the Sarmatian–Pliocene flexural Klagenfurt basin. The Reifnitz tonalite is dated for the first time, and yields a laser ICP-MS U–Pb zircon age of 30.72±0.30 Ma. The (U–Th–Sm)/He apatite age of the tonalite is 27.6 ± 1.8 Ma implying rapid Late Oligocene cooling of the tonalite to ca. 60 °C. The Reifnitz tonalite intruded into a retrogressed amphibolite-grade metamorphic basement with a metamorphic overprint of Cretaceous age (40Ar/39Ar white mica plateau age of 90.7 ± 1.6 Ma). This fact indicates that pervasive Alpine metamorphism of Cretaceous age extends southwards almost up to the Periadriatic fault. Based on the exhumation and erosion history of the Reifnitz tonalite and the hosting Wörthersee half window formed by the Wörthersee anticline, the age of gentle folding of Austroalpine units in the south-eastern part of the Eastern Alps is likely of Oligocene age. North of the Wörthersee antiform, Upper Cretaceous–Eocene, Oligocene and Miocene sedimentary rocks of the Krappfeld basin are preserved in a gentle synform, suggesting that the top of the Krappfeld basin has always been near the Earth’s surface since the Late Cretaceous. The new data imply, therefore, that the Reifnitz tonalite is part of a post-30 Ma antiform, which was likely exhumed, uplifted and eroded in two steps. In the first step, which is dated to ca. 31–27 Ma, rapid cooling to ca. 60 °C and exhumation occurred in an E–W trending antiform, which formed as a result of a regional N–S compression. In the second step of the Sarmatian–Pliocene age a final exhumation occurred in the peripheral bulge in response to the lithospheric flexure in front of the overriding North Karawanken thrust sheet. The Klagenfurt basin developed as a flexural basin at the northern front of the North Karawanken, which represent a transpressive thrust sheet of a positive flower structure related to the final activity along the Periadriatic fault. In the Eastern Alps, on a large scale, the distribution of Periadriatic plutons and volcanics seems to monitor a northward or eastward shift of magmatic activity, with the main phase of intrusions ca. 30 Ma at the fault itself.

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Loess encounters of three kinds: Charles Lyell talks about, reads about, and looks at loess

Abstract

Charles Lyell (1797–1875) was an important loess pioneer. His major contribution was to distribute information on the nature and existence of loess via his influential book ‘The Principles of Geology’. He was obviously impressed by loess when he encountered it; the initial encounter can be split into three phases: conversations about loess; confronting the actual material in the field; and reading about loess in the literature. Detail can be added to an important phase in the scientific development of the study of loess. Significant events include conversations with Hibbert in 1831, conversations and explorations with von Leonhard and Bronn in 1832, the opportunity to include a section on loess in vol. 3 of ‘Principles’ for publication in 1833, a substantial Rhineland excursion in 1833, the reporting of the results of this excursion in 1834, discussions at the German Association for the Advancement of Science meeting in Bonn in 1835. Of all the people encountered perhaps H.G. Bronn was the most significant. Lyell eventually listed eleven people as relevant to the loess writings: Bronn, von Leonhard, Boue, Voltz, Steininger, Merian, Rozet, Hibbert, Noeggerath, von Meyer, Horner – of these Bronn, von Leonhard, Hibbert and Horner appear to have been the most significant, viewed from 2015.

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Heavy-mineral analysis as a tool in tephrochronology, with an example from the La Sal Mountains, Utah, U.S.A.

Abstract

An essentially pure tephra layer on a steep slope in the La Sal Mountains, Utah, U.S.A., is correlated with the 1.65 Ma old Guaje Tephra derived from the Jemez Mountains, New Mexico, U.S.A. The heavy-mineral contents and glass shards in sediments beneath the La Sal tephra layer indicate that tephra constituents are contained in deposits considerably older than the pure layer. This suggests that tephra material may become reworked while retaining its pure character, possibly due to laminar transport or to dislocation in a frozen condition. This raises the need to handle tephrochronological findings with great care.

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Thermal history of the Podhale Basin in the internal Western Carpathians from the perspective of apatite fission track analyses

Abstract

The thermal history of the Paleogene Podhale Basin was studied by the apatite fission track (AFT) method. Twenty four Eocene-Oligocene sandstone samples yielded apparent ages from 13.8 ± 1.6 to 6.1 ± 1.4 Ma that are significantly younger than their stratigraphic age and thus point to a post-depositional resetting. The thermal event responsible for the age resetting is interpreted as a combination of heating associated with mid-Miocene volcanism and variable thickness of Oligocene and potentially also Miocene sediments. Extending the mid-Miocene thermal event found in the Inner Carpathians into the Podhale Basin as a likely heat source suggests that the amount of denudation in the Podhale Basin determined only on the basis of heat related to the thickness of sedimentary sequence might have be significantly overestimated. Two samples from the western part of the basin that yielded 31.0 ± 4.3 and 26.9 ± 4.7 Ma are interpreted as having mixed ages resulting from partial resetting in temperature conditions within the AFT partial annealing zone. This observation agrees very well with reported vitrinite reflectance and illite-smectite thermometry, which indicate a systematic drop of the maximum paleotemperatures towards the western side of the basin.

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